JP2019094508A - Reinforcement film - Google Patents

Abstract

An object of the present invention is to provide a reinforcing film having both low initial tackiness and strong tackiness during use, and having improved and stabilized performance. The reinforcing film includes a support substrate having a first surface and a second surface, and a pressure-sensitive adhesive layer laminated on the first surface of the support substrate. The support substrate includes a resin film as a base film. The second surface of the pressure-sensitive adhesive layer is fixed to the first surface of the support substrate, and the first surface of the pressure-sensitive adhesive layer is in contact with a peelable surface having a water contact angle of 100 ° or more. The pressure-sensitive adhesive layer contains a polymer A having a Tg of less than 0 ° C. and a polymer B which is a copolymer of a monomer having a polyorganosiloxane skeleton and a (meth) acrylic monomer. The above-mentioned reinforcing film has an adhesive force N2 after heating at 80 ° C. for 5 minutes after application and then standing at 23 ° C. for 30 minutes after application and 10 times or more the adhesive force N1 after applying and then leaving at 23 ° C. for 30 minutes. [Selection diagram] Fig. 1

Description

  The present invention relates to a reinforcing film.

  The pressure-sensitive adhesive sheet is used for the purpose of adhesion between adherends, fixing of articles to the adherend, reinforcement of the adherend, and the like by firmly adhering to the adherend. Conventionally, for such purpose, a pressure-sensitive adhesive sheet has been used which exhibits high adhesive strength from the early stage of bonding. Moreover, recently, as in Patent Documents 1 to 3, there has been proposed a pressure-sensitive adhesive sheet which exhibits low adhesive strength at the initial stage of application to an adherend, and thereafter can greatly increase the adhesive strength. According to the pressure-sensitive adhesive sheet having such a characteristic, before the rise of the adhesive strength, the adhesive sheet exhibits re-sticking property (rework property) useful for suppressing the yield decrease due to the sticking mistake or the sticking failure of the pressure-sensitive adhesive sheet. After rising, it can exhibit strong tackiness suitable for the intended purpose of use of the pressure-sensitive adhesive sheet.

JP, 2014-224227, A Patent No. 5890596 Patent No. 5951153 gazette

  In Patent Documents 1 to 3, a pressure-sensitive adhesive sheet having both the above-mentioned properties, ie, the initial low tackiness and the strong tackiness at the time of use, is studied mainly from the viewpoint of the properties and composition of the pressure sensitive adhesive. On the other hand, about the adhesive sheet (adhesive sheet with a base material) provided with the support base material which supports such an adhesive agent, there is still room for examination. The present inventor paid attention to a reinforcing film having a configuration using a resin film as a supporting substrate as one form of a substrate-attached pressure-sensitive adhesive sheet having the above-mentioned characteristics, and the reinforcing film The present invention has been completed through studies of performance improvement and stabilization.

  According to this specification, there is provided a reinforcing film comprising a supporting substrate having a first surface and a second surface, and a pressure-sensitive adhesive layer laminated on the first surface of the supporting substrate. The support substrate contains a resin film as a base film. The second surface of the pressure-sensitive adhesive layer is fixed to the first surface of the support base, and the first surface of the pressure-sensitive adhesive layer is in contact with the releasable surface. Here, the water contact angle of the releasable surface is 100 degrees or more. The pressure-sensitive adhesive layer contains a polymer A having a glass transition temperature (Tg) of less than 0 ° C., and a polymer B which is a copolymer of a monomer having a polyorganosiloxane skeleton and a (meth) acrylic monomer. The adhesive film N2 of the above-mentioned pressure-sensitive adhesive layer after adhesion of the first surface of the above-mentioned pressure-sensitive adhesive layer to a stainless steel plate and heating at 80 ° C. for 5 minutes and then left at 23 ° C. for 30 minutes After bonding the first surface to a stainless steel plate, the adhesive strength is at least 10 times the adhesive strength N1 after standing for 30 minutes at 23 ° C.

  The reinforcing film having such a configuration is configured such that the adhesive strength N2 (hereinafter also referred to as “adhesive after heating”) is 10 times or more of the adhesive strength N1 (hereinafter also referred to as “initial adhesive strength”). Accordingly, it is possible to achieve both good reworkability utilizing the initial low adhesion and high reinforcing performance utilizing the strong adhesion to the adherend at the time of use of the adherend. In addition, the first surface of the pressure-sensitive adhesive layer (the surface on the side to be attached to the adherend. Hereinafter, also referred to as the "adhesive surface") is in contact with the releasable surface having a water contact angle of 100 degrees or more. The influence of the storage conditions of the reinforcing film on the performance of the reinforcing film can be effectively reduced. For example, even if the reinforcing film prior to use (ie, prior to application to the adherend) is stored at a temperature above room temperature, the reinforced film after storage will still have low initial tack and use of the adherend. Strong adhesiveness can be exhibited appropriately. And since the said 2nd surface (The surface on the opposite side to the adhesive surface. It is also hereafter called back.) Of an adhesive layer adheres to the 1st surface of a support base material, a pressure-sensitive adhesive layer is adhered on an adherend. It is difficult to cause an event (an anchor failure) in which the support substrate is peeled off from the pressure-sensitive adhesive layer, and the integrity of the adherend and the support substrate can be effectively maintained.

  In the following, the ratio of adhesion after heating to initial adhesion, that is, N2 / N1 is sometimes referred to as "adhesion increase ratio". In addition, the first surface of the support substrate, that is, the surface to which the pressure-sensitive adhesive layer is fixed may be referred to as the "front surface", and the second surface of the support substrate may be referred to as the "back surface". Moreover, the thing of a peelable surface may be abbreviated and it may be called "peeling surface."

  In some embodiments of the reinforcing film disclosed herein, the surface of a release layer containing silicon (Si) can be preferably used as the release surface. According to the reinforcing film of the structure which made the adhesive surface contact | abut on the peelable surface of such a composition, the raise of the initial stage adhesive force by preserve | saving in a temperature range higher than room temperature can be suppressed better. One typical example of a silicon-containing release layer is a release layer formed by a silicone-based release treatment agent.

  In some other embodiments of the reinforcing film disclosed herein, the surface of a release layer formed of a long chain alkyl release agent can be used as the release surface. In a reinforced film in which the adhesive surface is in contact with a peelable surface having a water contact angle of 100 ° or more formed by a long-chain alkyl-based release treatment agent, the initial tackiness increases due to storage at a temperature higher than room temperature. Can be effectively suppressed.

  It is preferable that the thickness of the said support base material is 30 micrometers or more. According to the reinforcing film of the structure which the adhesive layer adhered to the support base material of such thickness, a favorable reinforcement effect is easy to be acquired.

  In some aspects of the reinforcing film disclosed herein, the thickness of the support substrate may be 1.1 times or more and 10 times or less the thickness of the pressure-sensitive adhesive layer. According to the reinforcing sheet of such a configuration, a good reinforcing effect can be easily obtained.

  In some embodiments, as the polymer B, one having a weight average molecular weight (Mw) of 10000 or more and 50000 or less can be preferably used. According to the polymer B in which Mw is in the above range, a reinforcing film having a high adhesive strength increase ratio is easily realized.

  In some embodiments, the content of the polymer B in the pressure-sensitive adhesive layer can be in the range of 0.05 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the polymer A. According to the content in the above range, a reinforcing film having a high adhesive strength increase ratio is easily realized.

  In some aspects of the reinforcement film disclosed herein, the releasable surface may be the surface of a release liner. The reinforcing film of this aspect peels off the release liner from the adhesive surface to expose the adhesive surface and affixes the adhesive surface to an adherend, whereby the initial low tackiness and the use of the adherend are achieved. Strong adhesiveness can be suitably made compatible.

  In some other aspects of the reinforcement film disclosed herein, the releasable surface may be the second side (back side) of the support substrate. That is, in the reinforcing film disclosed herein, the back surface of the support substrate may be a peelable surface having a water contact angle of 100 degrees or more, and the adhesive surface may be in contact with the back surface. The reinforcing film of this aspect peels the back surface of the support substrate from the adhesive surface to expose the adhesive surface, and affixes the adhesive surface to the adherend, whereby the initial low adhesiveness and the adherend are used. Strong adhesiveness can be suitably made compatible.

  A combination of the above-described elements as appropriate may also be included in the scope of the invention for which protection by a patent is sought by the present patent application.

It is sectional drawing which shows typically the structure of the reinforcement film which concerns on one Embodiment. It is sectional drawing which shows typically the structure of the reinforcement film which concerns on other one Embodiment.

Hereinafter, preferred embodiments of the present invention will be described. Matters other than the matters specifically mentioned in the present specification and necessary for the practice of the present invention are based on the teaching of the practice of the invention described in the present specification and the common general knowledge at the time of filing. It can be understood by the vendor. The present invention can be implemented based on the contents disclosed in the present specification and common technical knowledge in the field.
In the following drawings, the same reference numerals may be given to members / parts having the same function, and overlapping descriptions may be omitted or simplified. In addition, the embodiments described in the drawings are schematically illustrated in order to clearly explain the present invention, and the sizes and scales of products actually provided are not necessarily accurately represented.

  Moreover, in this specification, the term "acrylic polymer" refers to a polymer containing monomer units derived from (meth) acrylic monomers in the polymer structure, and is typically a monomer derived from (meth) acrylic monomers A polymer containing more than 50% by weight of units. Further, the (meth) acrylic monomer refers to a monomer having at least one (meth) acryloyl group in one molecule. Here, "(meth) acryloyl group" is a meaning which generally points out an acryloyl group and a methacryloyl group. Therefore, the concept of the (meth) acrylic monomer referred to herein may include both a monomer having an acryloyl group (acrylic monomer) and a monomer having a methacryloyl group (methacrylic monomer). Similarly, in the present specification, “(meth) acrylic acid” means acrylic acid and methacrylic acid, and “(meth) acrylate” generally means acrylate and methacrylate, respectively.

<Example of structure of reinforcing film>
The reinforcing film disclosed herein comprises at least a supporting substrate having a first surface and a second surface, and a pressure-sensitive adhesive layer laminated on the first surface of the supporting substrate. As a support base material, what contains a resin film as a base film is used. Hereinafter, the support substrate may be simply referred to as "substrate".

  The structure of the reinforcing film according to one embodiment is schematically shown in FIG. The reinforcing film 1 includes a sheet-like support base 10 having a first surface (front surface) 10A and a second surface (back surface) 10B, and an adhesive layer 21 fixed to the first surface 10A and laminated thereon. It is comprised as a single-sided adhesive sheet with a base material provided with. The pressure-sensitive adhesive layer 21 contains at least a polymer A and a polymer B described later. The pressure-sensitive adhesive layer 21 has a first surface (adhesive surface) 21A and a second surface (rear surface) 21B.

  In the reinforcing film 1 before being attached to the adherend, the adhesive surface 21A is in contact with the peelable surface (peeling surface) having a water contact angle of 100 degrees or more. As the peeling surface, for example, as shown in FIG. 1, the peeling surface of the peeling liner 31 in which at least the surface 31A on the side facing the pressure-sensitive adhesive layer 21 has a water contact angle of 100 degrees or more is used. be able to. As described above, the reinforcing film 1 in which the adhesive surface 21A is in contact with the release surface 31A of the release liner 31 can be grasped as a component of the release liner-attached reinforcing film 100 including the reinforcing film 1 and the release liner 31. As the release liner 31, for example, it is preferable to use one configured such that the single side becomes the above-mentioned release surface by providing a release layer with a release treatment agent on one side of a sheet-like base material (liner base material). .

  When the reinforcing film 1 is attached to the adherend, the release liner 31 is peeled off from the adhesive surface 21A, and the exposed adhesive surface 21A is crimped to the adherend. Since the reinforcing film 1 is configured to have an adhesive strength increase ratio of 10 or more, it is possible to exhibit good reworkability at the initial stage of application to the adherend, and after the adhesive strength is increased, By firmly fixing the support substrate 10 to the adherend via the pressure-sensitive adhesive layer 21, the adherend can be reinforced. Here, the back surface 21B of the pressure-sensitive adhesive layer 21 is fixed to the front surface 10A of the support base 10, and peeling (injury failure) at the interface between the pressure-sensitive adhesive layer 21 and the support base 31 is prevented. Thereby, the integrity between the adherend and the support base 10 can be reliably maintained, and a high reinforcing effect can be exhibited.

  In addition, in the reinforcement film 1 shown in FIG. 1, you may utilize 2nd surface (back surface) 10B of the support base material 10 as a peeling surface which 21 A of adhesive surfaces contact | abut. For example, by winding the reinforcing film 1, the adhesive surface 21 A is in contact with the back surface 10 B of the support base 10 and protected (roll form), or the back surface 10 B of the one reinforcing film 1 is reinforced. It can be set as the form etc. in which the reinforcement film 1 of several sheets was laminated | stacked so that the adhesive surface 21A of this may contact | abut.

  The structure of a reinforcing film according to another embodiment is schematically shown in FIG. The reinforcing film 2 includes a sheet-like support base 10 having a first surface 10A and a second surface 10B, and a pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer) 21 fixed to and laminated on the first surface 10A. The pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer) 22 laminated on the second surface 10B is configured as a double-sided pressure-sensitive adhesive sheet with a substrate. The first pressure-sensitive adhesive layer 21 contains at least a polymer A and a polymer B described later. In the reinforcing film 2, the second surface (rear surface) 21B of the first pressure-sensitive adhesive layer 21 is fixed to the first surface of the support base, and the surface (first pressure-sensitive adhesive surface) 21A of the first pressure-sensitive adhesive layer 21 The adhesive force increase ratio of 10 is set to 10 or more. This makes it possible to achieve both good reworkability and high reinforcement effect. The reinforcing film 2 is used by sticking the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 to different portions of the adherend. The places where the pressure-sensitive adhesive layers 21 and 22 are attached may be places of different members, or may be different places in a single member. Further, the composition of the second pressure-sensitive adhesive layer 22 and the adhesive strength increase ratio of the surface (second pressure-sensitive adhesive surface) 22A of the second pressure-sensitive adhesive layer 22 are not particularly limited.

  As shown in FIG. 2, the reinforcing film 2 before being attached to the adherend has peeling surfaces 31A and 32A, respectively, in which the first adhesive surface 21A and the second adhesive surface 22A face at least the adhesive layers 21 and 22 respectively. It can be a component of the reinforcement film 200 with a release liner in a form protected against the release liners 31, 32. Alternatively, the release liner 32 is omitted, and the second adhesive surface 22A is formed by superposing the reinforcing film 2 on the release liner 31 using the release liner 31 whose both surfaces are release surfaces 31A and 31B, and spirally winding the same. The reinforcing film with a release liner may be configured in a form (roll form) in contact with the back surface 31B of the release liner 31 for protection. In any case, of the peeling surfaces 31A and 32A, the peeling surface 31A in contact with at least the first adhesive surface 21A is a peeling surface having a water contact angle of 100 degrees or more.

<Pressure-sensitive adhesive layer>
The reinforcing film disclosed herein is a copolymer of a polymer A having a Tg of less than 0 ° C., a monomer having a polyorganosiloxane skeleton, and a (meth) acrylic monomer on the first surface of a supporting substrate. And a polymer B. Such an adhesive layer may be formed from an adhesive composition containing polymer A or a precursor thereof and polymer B. The form of the pressure-sensitive adhesive composition is not particularly limited, and may be various forms such as water dispersion type, solvent type, hot melt type, active energy ray curable type (for example, photocurable type).

(Polymer A)
As the polymer A, acrylic polymers, rubber polymers, polyester polymers, urethane polymers, polyether polymers, silicone polymers, polyamide polymers, fluorine polymers, etc. known in the field of pressure-sensitive adhesives in the room temperature range One or more of various polymers exhibiting rubber elasticity can be used.

  The Tg of polymer A is typically less than 0 ° C., preferably less than −10 ° C., more preferably less than −20 ° C. A pressure-sensitive adhesive containing polymer A having a Tg of less than 0 ° C. is suitable for realizing a reinforcing film having a high adhesion increase ratio because it exhibits appropriate fluidity (for example, the mobility of polymer chains contained in the pressure-sensitive adhesive). ing. In some embodiments, the Tg of polymer A may be, for example, less than -30 ° C, may be less than -40 ° C, may be less than -50 ° C, and may be less than -60 ° C. When the Tg of the polymer A is low, the rise in adhesion after application to an adherend tends to be facilitated. The lower limit of the Tg of the polymer A is not particularly limited. From the viewpoint of the availability of the material and the improvement of the cohesion of the pressure-sensitive adhesive layer, a polymer A having a Tg of −80 ° C. or more can usually be suitably employed.

Here, in this specification, the Tg of a polymer means a nominal value described in the literature, a catalog or the like, or a Tg determined by the Fox equation based on the composition of a monomer component used for the preparation of the polymer. . The Fox equation, as shown below, is a relationship between the Tg of the copolymer and the glass transition temperature Tgi of a homopolymer obtained by homopolymerizing each of the monomers constituting the copolymer.
1 / Tg = Σ (Wi / Tgi)
In the above Fox equation, Tg is the glass transition temperature of the copolymer (unit: K), Wi is the weight fraction of monomer i in the copolymer (copolymerization ratio by weight), Tgi is a homopolymer of monomer i Represents the glass transition temperature (unit: K) of When the target polymer of the Tg specification is a homopolymer, the Tg of the homopolymer matches the Tg of the target polymer.

  As a glass transition temperature of the homopolymer used for calculation of Tg, the value as described in a well-known data shall be used. Specifically, numerical values are given in “Polymer Handbook” (Third Edition, John Wiley & Sons, Inc., 1989). The highest value is adopted about the monomer in which a plurality of types of values are described in the above-mentioned Polymer Handbook.

As a glass transition temperature of a homopolymer of a monomer not described in the above-mentioned Polymer Handbook, a value obtained by the following measuring method is used.
Specifically, 100 parts by weight of a monomer, 0.2 parts by weight of 2,2'-azobisisobutyronitrile and acetic acid as a polymerization solvent in a reactor equipped with a thermometer, a stirrer, a nitrogen introducing pipe and a reflux condenser 200 parts by weight of ethyl is charged and stirred for 1 hour while flowing nitrogen gas. After oxygen in the polymerization system is removed in this manner, the temperature is raised to 63 ° C. and reaction is carried out for 10 hours. Then, it is cooled to room temperature to obtain a homopolymer solution having a solid concentration of 33% by weight. The homopolymer solution is then cast coated on a release liner and dried to make a test sample (sheet-like homopolymer) about 2 mm thick. This test sample is punched out into a disk shape of 7.9 mm in diameter, sandwiched by parallel plates, and shear strain at a frequency of 1 Hz using a visco-elasticity tester (manufactured by TA Instruments Japan, model name "ARES") The visco-elasticity is measured by a shear mode at a temperature rising rate of -70 ° C. to 150 ° C. and a temperature rising rate of 5 ° C./min, and the temperature corresponding to the peak top temperature of tan δ is taken as the Tg of the homopolymer.

Although not particularly limited, it is appropriate that the weight average molecular weight (Mw) of the polymer A is usually about 5 × 10 ⁴ or more. According to the polymer A of such Mw, it is easy to obtain a pressure-sensitive adhesive having good cohesion. In some embodiments, the Mw of the polymer A may be, for example, 10 × 10 ⁴ or more, 20 × 10 ⁴ or more, or 30 × 10 ⁴ or more. In addition, it is appropriate that the Mw of the polymer A is usually about 500 × 10 ⁴ or less. The polymer A of such Mw is suitable for realizing a reinforcing film having a high adhesion increase ratio, since it is easy to form a pressure-sensitive adhesive that exhibits appropriate fluidity (motility of polymer chains).

  In addition, in this specification, Mw of the polymer A and the polymer B can be determined by gel permeation chromatography (GPC) in terms of polystyrene. More specifically, Mw can be measured according to the method and conditions described in the examples described later.

  An acrylic polymer can be preferably employed as the polymer A in the reinforcing film disclosed herein. When an acrylic polymer is used as the polymer A, good compatibility with the polymer B tends to be easily obtained. The good compatibility between the polymer A and the polymer B is preferable because it can contribute to the reduction of the initial tack and the improvement of the tack after heating through the improvement of the mobility of the polymer B in the pressure-sensitive adhesive layer.

The acrylic polymer is, for example, a polymer containing 50% by weight or more of a monomer unit derived from (meth) acrylic acid alkyl ester, that is, 50% by weight or more of the total amount of monomer components for preparing the acrylic polymer ) It may be a polymer which is an acrylic acid alkyl ester. As the (meth) acrylic acid alkyl ester, a (meth) acrylic acid alkyl ester having a linear or branched alkyl group having 1 to 20 carbon atoms (that is, C _1-20 ) can be preferably used. The proportion of (meth) acrylic acid C _1-20 alkyl ester in the total amount of monomer components may be, for example, 50% by weight or more, 60% by weight or more, 70% by weight or more because of easy balance of properties. May be. For the same reason, the proportion of (meth) acrylic acid C _1-20 alkyl ester in the total amount of monomer components may be, for example, 99.9% by weight or less, 98% by weight or less, or 95% by weight or less . In some embodiments, the proportion of (meth) acrylic acid C _1-20 alkyl ester in the total amount of monomer components may be, for example, 90% by weight or less, 85% by weight or less, or 80% by weight or less.

Non-limiting specific examples of (meth) acrylic acid C _1-20 alkyl ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate ( (Meth) acrylate n-butyl, (meth) acrylate isobutyl, (meth) acrylate s-butyl, (meth) acrylate t-butyl, pentyl (meth) acrylate, isopentyl (meth) acrylate, (meth) Hexyl acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, (meth ) Decyl acrylate, (meth) acrylate isodecyl, (meth) acrylate undecyl, (meta ) Dodecyl acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, stearyl (meth) acrylate, (meth) Isostearyl acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate and the like can be mentioned.

Among these, it is preferable to use at least (meth) acrylic acid C _1-18 alkyl ester, and it is more preferable to use at least (meth) acrylic acid C _1-14 alkyl ester. In some embodiments, the acrylic polymer is at least one selected from (meth) acrylic acid C _4-12 alkyl esters (preferably acrylic acid C _4-10 alkyl esters such as acrylic acid C _6-10 alkyl esters) May be contained as monomer units. For example, acrylic polymers comprising one or both of n-butyl acrylate (BA) and 2-ethylhexyl acrylate (2EHA) are preferred, and acrylic polymers comprising at least 2EHA are particularly preferred. Examples of other (meth) acrylic acid C _1-18 alkyl esters that can be preferably used include methyl acrylate, methyl methacrylate (MMA), n-butyl methacrylate (BMA), 2-ethylhexyl methacrylate (2EHMA) And isostearyl acrylate (ISTA).

  The monomer unit constituting the acrylic polymer together with the (meth) acrylic acid alkyl ester as the main component, if necessary, another monomer (copolymerizable monomer) copolymerizable with the (meth) acrylic acid alkyl ester May be included. As the copolymerizable monomer, a monomer having a polar group (for example, a carboxy group, a hydroxyl group, a nitrogen atom-containing ring, etc.) can be suitably used. A monomer having a polar group can serve to introduce a crosslinking point into the acrylic polymer or to enhance the cohesion of the acrylic polymer. The copolymerizable monomers can be used alone or in combination of two or more.

As non-limiting specific examples of copolymerizable monomers, the following may be mentioned.
Carboxy group-containing monomers: for example, acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, isocrotonic acid and the like.
Acid anhydride group-containing monomer: for example, maleic anhydride, itaconic anhydride.
Hydroxy group-containing monomer: for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) acrylic 4-hydroxybutyl acid, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxy lauryl (meth) acrylate, (4-hydroxy acrylate (Meth) hydroxyalkyl (meth) acrylates such as methyl (cyclohexyl) methyl (meth) acrylate and the like.
Monomers containing sulfonic acid group or phosphoric acid group: for example, styrene sulfonic acid, allyl sulfonic acid, sodium vinyl sulfonic acid, 2- (meth) acrylamido-2-methylpropane sulfonic acid, (meth) acrylamidopropane sulfonic acid, sulfo Propyl (meth) acrylate, (meth) acryloyloxy naphthalene sulfonic acid, 2-hydroxyethyl acryloyl phosphate and the like.
Epoxy group-containing monomers: for example, epoxy group-containing acrylates such as glycidyl (meth) acrylate and 2-ethyl glycidyl ether (meth) acrylate, allyl glycidyl ether, glycidyl ether (meth) acrylate and the like.
Cyano group-containing monomer: for example, acrylonitrile, methacrylonitrile and the like.
Isocyanate group-containing monomer: for example, 2-isocyanatoethyl (meth) acrylate and the like.
Amide group-containing monomers: for example, (meth) acrylamide; N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N, N-dipropyl (meth) acrylamide, N, N-diisopropyl (meth) N, N-dialkyl (meth) acrylamides such as acrylamide, N, N-di (n-butyl) (meth) acrylamide, N, N-di (t-butyl) (meth) acrylamide, etc .; N-ethyl (meth) N-alkyl (meth) acrylamides such as acrylamide, N-isopropyl (meth) acrylamide, N-butyl (meth) acrylamide, N-n-butyl (meth) acrylamide and the like; N-vinylcarboxylic acid amides such as N-vinylacetamide and the like A monomer having a hydroxyl group and an amide group, for example, N- (2-hydro) Syethyl) (meth) acrylamide, N- (2-hydroxypropyl) (meth) acrylamide, N- (1-hydroxypropyl) (meth) acrylamide, N- (3-hydroxypropyl) (meth) acrylamide, N- (2) N-hydroxyalkyl (meth) acrylamides such as -hydroxybutyl) (meth) acrylamide, N- (3-hydroxybutyl) (meth) acrylamide, N- (4-hydroxybutyl) (meth) acrylamide; alkoxy groups and amides Monomers having a group such as N-alkoxyalkyl (meth) acrylamides such as N-methoxymethyl (meth) acrylamide, N-methoxyethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, etc .; N-dimethylaminopropyl (Meth) acrylamide, N- (meth) acryloyl morpholine.
Monomers having a nitrogen atom-containing ring: for example, N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N- Vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N- (meth) acryloyl-2-pyrrolidone, N- (meth) acryloylpiperidine, N- (meth) acryloylpyrrolidine, N-vinylmorpholine, N-vinyl-3 -Morpholinone, N-vinyl-2-caprolactam, N-vinyl-1,3-oxazin-2-one, N-vinyl-3,5-morpholindione, N-vinylpyrazole, N-vinylisoxazole, N-vinyl Thiazole, N-vinylisothiazole, N-vinyl pyridazine (E.g., lactams such as N- vinyl-2-caprolactam).
Monomers having a succinimide skeleton: for example, N- (meth) acryloyloxymethylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, N- (meth) acryloyl-8-oxyhexamethylene succinimide and the like.
Maleimides: For example, N-cyclohexyl maleimide, N-isopropyl maleimide, N-lauryl maleimide, N-phenyl maleimide and the like.
Itaconimides: for example, N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide, N-2-ethylhexylconacimide, N-cyclohexylitaconimide, N-lauryl Itacon imide etc.
Aminoalkyl (meth) acrylates: for example, aminoethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, (meth) acrylate t -Butylaminoethyl.
Alkoxy group-containing monomers: for example, 2-methoxyethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, propoxyethyl (meth) acrylate, (meth) acrylate (Meth) acrylic acid alkoxyalkyls such as butoxyethyl and (meth) acrylic acid ethoxypropyl; (meth) acrylic acid methoxyalkylene glycol (meth) acrylic acid methoxyethylene glycol and (meth) acrylic acid methoxypolypropylene glycol and the like Kind.
Vinyl esters: For example, vinyl acetate, vinyl propionate and the like.
Vinyl ethers: For example, vinyl alkyl ethers such as methyl vinyl ether and ethyl vinyl ether.
Aromatic vinyl compounds: For example, styrene, α-methylstyrene, vinyl toluene and the like.
Olefins: For example, ethylene, butadiene, isoprene, isobutylene etc.
(Meth) acrylic esters having an alicyclic hydrocarbon group: for example, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate and the like.
(Meth) acrylic acid ester having an aromatic hydrocarbon group: for example, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate and the like.
In addition, heterocycle-containing (meth) acrylates such as tetrahydrofurfuryl (meth) acrylate, halogen atoms (meth) acrylates such as vinyl chloride and fluorine atoms (meth) acrylates, silicon atoms such as silicone (meth) acrylates (Meth) acrylates, (meth) acrylic esters obtained from terpene compound derivative alcohols, etc.

  When such a copolymerizable monomer is used, the amount thereof to be used is not particularly limited, but usually, it is suitable to be 0.01% by weight or more of the total amount of monomer components. The amount of the copolymerizable monomer used may be 0.1% by weight or more, or 1% by weight or more of the total amount of the monomer components, from the viewpoint of exhibiting the effects of the use of the copolymerizable monomer better. The amount of the copolymerizable monomer used can be 50% by weight or less of the total amount of the monomer components, and is preferably 40% by weight or less. Thereby, the cohesive force of the pressure-sensitive adhesive can be prevented from becoming too high, and the tackiness at normal temperature (25 ° C.) can be improved.

  In some embodiments, the acrylic polymer comprises, as monomer units, an N-vinyl cyclic amide represented by the following general formula (M1) and a hydroxyl group-containing monomer (a monomer having a hydroxyl group and another functional group, such as a hydroxyl group and an amide And at least one monomer selected from the group consisting of

ここで、上記一般式（Ｍ１）中のＲ^１は、２価の有機基である。

Here, R ¹ in the above general formula (M1) is a divalent organic group.

  By using N-vinyl cyclic amide, the cohesion and polarity of the pressure-sensitive adhesive can be adjusted to improve adhesion after heating. Specific examples of N-vinyl cyclic amide include N-vinyl-2-pyrrolidone, N-vinyl-2-piperidone, N-vinyl-3-morpholinone, N-vinyl-2-caprolactam, N-vinyl-1,3. -Oxazin-2-one, N-vinyl-3,5-morpholindione, etc. may be mentioned. Particularly preferred are N-vinyl-2-pyrrolidone and N-vinyl-2-caprolactam.

  The amount of N-vinyl cyclic amide used is not particularly limited, but generally 0.01% by weight or more (preferably 0.1% by weight or more, for example, 0.5% by weight or more) of the total amount of monomer components for preparing an acrylic polymer % Or more) is appropriate. In some embodiments, the amount of N-vinyl cyclic amide used may be 1% by weight or more, 5% by weight or more, or 10% by weight or more of the total amount of the above monomer components. In addition, from the viewpoint of improving tackiness at normal temperature (25 ° C.) and flexibility at low temperature, the amount of N-vinyl cyclic amide used is usually 40% by weight or less of the total amount of the above monomer components. , 30 wt% or less, or 20 wt% or less.

  By using a hydroxyl group-containing monomer, the cohesion and polarity of the pressure-sensitive adhesive can be adjusted to improve the adhesion after heating. In addition, the hydroxyl group-containing monomer can provide a reaction point with a crosslinking agent (for example, an isocyanate-based crosslinking agent) described later, and can enhance the cohesion of the adhesive by the crosslinking reaction.

  Examples of hydroxyl group-containing monomers include 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, N- (2-hydroxyethyl) (meth) acrylamide and the like It can be used suitably. Among them, 2-hydroxyethyl acrylate (HEA), 4-hydroxybutyl acrylate (4HBA), and N- (2-hydroxyethyl) acrylamide (HEAA) are preferred as preferable examples.

  The amount of the hydroxyl group-containing monomer to be used is not particularly limited, but usually 0.01% by weight or more (preferably 0.1% by weight or more, for example 0.5% by weight or more) of the total amount of monomer components for preparing the acrylic polymer It is appropriate to use In some embodiments, the amount of the hydroxyl group-containing monomer used may be 1% by weight or more, 5% by weight or more, or 10% by weight or more of the total amount of the monomer components. In addition, from the viewpoint of improving tackiness at normal temperature (25 ° C.) and improving flexibility at low temperature, the amount of the hydroxyl group-containing monomer used is usually 40% by weight or less of the total amount of the above monomer components. The content may be less than or equal to 20% by weight, or less than or equal to 10% by weight, or less than or equal to 5% by weight.

  In some embodiments, an N-vinyl cyclic amide and a hydroxyl group-containing monomer can be used in combination as the copolymerizable monomer. In this case, the total amount of the N-vinyl cyclic amide and the hydroxyl group-containing monomer can be, for example, 0.1% by weight or more of the total amount of monomer components for preparing the acrylic polymer. It may be 5% by weight or more, 10% by weight or more, 15% by weight or more, 20% by weight or more, or 25% by weight or more. In addition, the total amount of the N-vinyl cyclic amide and the hydroxyl group-containing monomer can be, for example, 50% by weight or less of the total amount of monomer components, and preferably 40% by weight or less.

  The method for obtaining an acrylic polymer is not particularly limited, and various polymerization methods known as synthetic methods for acrylic polymers, such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, photopolymerization, etc. Can be adopted as appropriate. In some embodiments, solution polymerization methods may be preferably employed. The polymerization temperature when performing solution polymerization can be appropriately selected according to the type of monomer and solvent used, the type of polymerization initiator, etc., and for example, it is about 20 ° C. to 170 ° C. (typically 40 ° C. to 140 ° C.) C).

  The initiator used for the polymerization can be appropriately selected from conventionally known thermal polymerization initiators, photo polymerization initiators and the like according to the polymerization method. The polymerization initiators can be used alone or in combination of two or more.

As a thermal polymerization initiator, for example, an azo polymerization initiator (for example, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2-methylbutyronitrile, 2,2′-azobis ( 2-Methylpropionic acid) dimethyl, 4,4′-azobis-4-cyanovaleric acid, azobisisovaleronitrile, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [2 -(5-Methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis (2-methylpropionamidine) disulfate, 2,2'-azobis (N, N'-dimethylene) (Isobutylamidine) dihydrochloride and the like); persulfates such as potassium persulfate; peroxide type polymerization initiators (for example, dibenzoyl peroxide, t-butyl permaleate, Lauroyl peroxide, etc.); redox polymerization initiators, and the like. In some embodiments, an azo polymerization initiator may be preferably employed.
The use amount of the thermal polymerization initiator is not particularly limited, but, for example, 0.01 to 5 parts by weight, preferably 0.05 to 5 parts by weight with respect to 100 parts by weight of the monomer component used for preparation of the acrylic polymer. The amount may be in the range of 3 parts by weight.

  The photopolymerization initiator is not particularly limited. For example, benzoin ether photopolymerization initiator, acetophenone photopolymerization initiator, α-ketol photopolymerization initiator, aromatic sulfonyl chloride photopolymerization initiator, photoactivity Oxime based photoinitiator, benzoin based photoinitiator, benzyl based photoinitiator, benzophenone based photoinitiator, ketal based photoinitiator, thioxanthone based photoinitiator, acyl phosphine oxide based photopolymerization initiation An agent etc. can be used. The use amount of the photopolymerization initiator is not particularly limited, but, for example, 0.01 part by weight to 5 parts by weight, preferably 0.05 parts by weight to 100 parts by weight of the monomer component used for preparation of the acrylic polymer The amount may be in the range of 3 parts by weight.

  In some embodiments, the acrylic polymer is a partially polymerized product in which a portion of the monomer component is polymerized by irradiating ultraviolet light (UV) to a mixture in which a polymerization initiator is blended with the monomer component as described above (acrylic In the form of polymer syrup, it can be included in the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer. A pressure-sensitive adhesive composition containing such an acrylic polymer syrup can be applied to a predetermined object and irradiated with ultraviolet light to complete the polymerization. That is, the said acrylic polymer syrup can be grasped | ascertained as a precursor of an acrylic polymer. The pressure-sensitive adhesive layer disclosed herein can be formed, for example, using a pressure-sensitive adhesive composition containing the above-mentioned acrylic polymer syrup and polymer B.

(Polymer B)
The polymer B in the art disclosed herein is a copolymer of a monomer having a polyorganosiloxane skeleton (hereinafter, also referred to as “monomer S1”) and a (meth) acrylic monomer. The polymer B can function as a tackiness increase retarder that contributes to the suppression of the initial tackiness and the improvement of the tackiness increase ratio due to the low polarity and motility of the polyorganosiloxane structure derived from the monomer S1. The monomer S1 is not particularly limited, and any monomer containing a polyorganosiloxane skeleton can be used. Monomer S1 promotes uneven distribution of polymer B on the surface of the pressure-sensitive adhesive layer in the reinforcing film before use (before application to the adherend) by the low polarity derived from its structure, and light peeling at the initial stage of bonding Develop sex (low tackiness). As the monomer S1, one having a structure having a polymerizable reactive group at one end (ie, one having one end reactivity) can be preferably used. By such copolymerization of the monomer S1 and the (meth) acrylic monomer, a polymer B having a polyorganosiloxane skeleton in the side chain is formed. The polymer B having such a structure tends to have low initial tack and high tack increase ratio due to the mobility and mobility of the side chain. The technology disclosed herein can be preferably practiced in a mode in which the majority (for example, 70 wt% or more, 85 wt% or more, or 95 wt% or more) of the monomer S1 used is one end reactive. Substantially all (e.g., 98 to 100 wt%) of monomer S1 may be single-ended reactive.

ここで、上記一般式（１），（２）中のＲ^３は水素またはメチルであり、Ｒ^４はメチル基または１価の有機基であり、ｍおよびｎは０以上の整数である。 As the monomer S1, for example, a compound represented by the following general formula (1) or (2) can be used. More specifically, X-22-174ASX, X-22-2426, X-22-2475, KF-2012 etc. are mentioned as one end reactive silicone oil made by Shin-Etsu Chemical Co., Ltd. The monomers S1 can be used alone or in combination of two or more.

Here, R ³ in the above general formulas (1) and (2) is hydrogen or methyl, R ⁴ is a methyl group or a monovalent organic group, and m and n are integers of 0 or more.

  The functional group equivalent of the monomer S1 is, for example, preferably 700 g / mol or more and less than 15000 g / mol, more preferably 800 g / mol or more and less than 10000 g / mol, and preferably 850 g / mol or more and less than 6000 g / mol. Is more preferable, and particularly preferably 1500 g / mol or more and less than 5000 g / mol. When the functional group equivalent of monomer S1 is less than 700 g / mol, the initial tack may not be sufficiently suppressed. When the functional group equivalent of the monomer S1 is 15000 g / mol or more, the increase in adhesion may be insufficient. When the functional group equivalent of the monomer S1 is in the above range, the compatibility (for example, compatibility with the polymer A) and mobility in the pressure-sensitive adhesive layer can be easily adjusted to an appropriate range, and the initial low tackiness and the object It becomes easy to implement | achieve the reinforcement film which makes compatible with the strong adhesiveness at the time of adhesion body use at a high level.

Here, "functional group equivalent" means the weight of the main skeleton (for example, polydimethylsiloxane) bonded to one functional group. The title unit g / mol is converted to 1 mol of functional group. The functional group equivalent of monomer S1 can be calculated, for example, from the spectral intensity of ¹ H-NMR (proton NMR) based on nuclear magnetic resonance (NMR). Calculating functional group equivalent of the monomer S1, based on the spectral intensity of ^{1 H-NMR (g / mol} ) ^is, 1 H-NMR based on general structure analysis method according to the spectral analysis, Japanese Patent No. 5951153, if necessary It can carry out with reference to the description of the publication.

When two or more kinds of monomers having different functional group equivalents are used as the monomer S1, an arithmetic average value can be used as the functional group equivalent of the monomer S1. That is, the functional group equivalent of monomer S1 consisting of n types of monomers (monomer S1 ₁ , monomer S1 ₂ ... Monomer S1 _n ) having different functional group equivalents can be calculated by the following formula.
Functional group equivalent of the monomer S1 (g / mol) = (monomer S1 ₁ functional group equivalent × monomer S1 ₁ of the amount + monomer S1 ₂ functional group equivalent × monomer S1 ₂ of the amount + ... + monomer S1 _n of the amount of the functional group equivalent × monomer S1 _n) / (monomer S1 ₁ of the amount + monomer S1 ₂ of the amount + ... + amount of monomer S1 _n)

  The content of the monomer S1 may be, for example, 5% by weight or more with respect to all the monomer components for preparing the polymer B, and 10% by weight or more from the viewpoint of exhibiting the effect as an adhesive force increase retarder better It is preferable to set it as 15 weight% or more, and it is good also as 20 weight% or more. In addition, the content of the monomer S1 is suitably 60% by weight or less with respect to all the monomer components for preparing the polymer B from the viewpoint of polymerization reactivity and compatibility, and 50% by weight or less It may be 40% by weight or less, or 30% by weight or less. If the content of the monomer S1 is less than 5% by weight, the initial tack may not be sufficiently suppressed. When the content of the monomer S1 is more than 60% by weight, the increase in adhesion may be insufficient.

  The monomer component used for the preparation of the polymer B contains, in addition to the monomer S1, (meth) acrylic monomers copolymerizable with the monomer S1. The mobility of the polymer B in the pressure-sensitive adhesive layer can be suitably controlled by copolymerizing one or more kinds of (meth) acrylic monomers with the monomer S1. Copolymerizing the monomer S1 and the (meth) acrylic monomer may also help to improve the compatibility of the polymer B with the polymer A (for example, an acrylic polymer).

As a (meth) acrylic-type monomer, the (meth) acrylic-acid alkylester is mentioned, for example. For example, one or more of the monomers exemplified above as (meth) acrylic acid alkyl esters that can be used when the polymer A is an acrylic polymer can be used as a copolymerization component of the polymer B. In some embodiments, polymer B is a (meth) acrylic acid C _4-12 alkyl ester (preferably a (meth) acrylic acid C _4-10 alkyl ester, such as a (meth) acrylic acid C _6-10 alkyl ester) At least one may be contained as a monomer unit. In some other embodiments, the polymer B contains at least one of methacrylic acid C _1-18 alkyl ester (preferably methacrylic acid C _1-14 alkyl ester, for example methacrylic acid C _1-10 alkyl ester) as a monomer unit It can. The monomer units constituting the polymer B may include, for example, one or more selected from MMA, BMA and 2EHMA.

  Another example of the (meth) acrylic monomer is a (meth) acrylic acid ester having an alicyclic hydrocarbon group. For example, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 1-adamantyl (meth) acrylate and the like can be used. In some embodiments, the polymer B may contain at least one selected from dicyclopentanyl methacrylate, isobornyl methacrylate and cyclohexyl methacrylate as monomer units.

  The amount of the (meth) acrylic acid alkyl ester and the alicyclic hydrocarbon group-containing (meth) acrylic acid ester used is, for example, 10% by weight or more and 95% by weight with respect to all the monomer components for preparing the polymer B %, May be 20% by weight to 95% by weight, may be 30% by weight to 90% by weight, and may be 40% by weight to 90% by weight, 50 % By weight or more and 85% by weight or less. The use of (meth) acrylic acid alkyl esters may be advantageous from the viewpoint of the ease of raising the adhesion by heating. In some embodiments, the used amount of (meth) acrylic acid ester having an alicyclic hydrocarbon group is, for example, 50 of the total amount of (meth) acrylic monomers contained in the monomer component for preparing the polymer B. It may be less than 30% by weight, less than 15% by weight, less than 10% by weight, or less than 5% by weight. It is not necessary to use (meth) acrylic acid ester having an alicyclic hydrocarbon group.

  As another example of the monomer that can be included together with the monomer S1 as the monomer unit constituting the polymer B, the carboxyl group-containing monomer exemplified above as the monomer that can be used when the polymer A is an acrylic polymer, acid anhydride group containing Monomer, hydroxyl group-containing monomer, epoxy group-containing monomer, cyano group-containing monomer, isocyanate group-containing monomer, amide group-containing monomer, monomer having a nitrogen atom-containing ring, monomer having a succinimide skeleton, maleimides, itaconimides, (meth) acrylic Acid amino alkyls, vinyl esters, vinyl ethers, olefins, (meth) acrylic acid ester having aromatic hydrocarbon group, heterocycle-containing (meth) acrylate, halogen atom-containing (meth) acrylate, terpene compound Resulting from the conductor alcohol (meth) acrylic acid ester.

  As still another example of a monomer that can be included together with the monomer S1 as a monomer unit constituting the polymer B, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di ( Oxyalkylene (meth) acrylates such as meta) acrylates, propylene glycol di (meth) acrylates, dipropylene glycol di (meth) acrylates, tripropylene glycol di (meth) acrylates; monomers having a polyoxyalkylene skeleton, such as polyethylene glycol And a polymerizable functional group such as (meth) acryloyl group, vinyl group and allyl group at one end of a polyoxyalkylene chain such as polypropylene glycol, etc. Polymerizable polyoxyalkylene ether having an ether structure (alkyl ether, aryl ether, aryl alkyl ether etc.); methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, propoxyethyl (meth) acrylate, (meth) ) Alkoxyalkyl (meth) acrylates such as butoxyethyl acrylate and ethoxypropyl (meth) acrylate; salts such as alkali metal (meth) acrylates; polyvalents such as trimethylolpropane tri (meth) acrylates Meta) acrylate: vinylidene halide, halogenated vinyl compounds such as (meth) acrylic acid 2-chloroethyl; 2-vinyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-isopropenyl-2- Oxazoline such as oxazoline Containing monomers; Aziridine group-containing monomers such as (meth) acryloyl aziridine, (meth) acrylic acid 2-aziridinyl ethyl; etc. (meth) acrylic acid 2- hydroxyethyl, (meth) acrylic acid 2-hydroxypropyl, Hydroxyl group-containing vinyl monomers such as adducts of lactones and (meth) acrylic acid-2-hydroxyethyl; fluorine-containing vinyl monomers such as fluorine-substituted (meth) acrylic acid alkyl esters; 2-chloroethyl vinyl ether, vinyl monochloroacetate, etc. Reactive halogen-containing vinyl monomers; organosilicon-containing vinyls such as vinyltrimethoxysilane, γ- (meth) acryloxypropyltrimethoxysilane, allyltrimethoxysilane, trimethoxysilylpropylallylamine, 2-methoxyethoxytrimethoxysilane Monomer; and the like can be given like; macromonomers having a radically polymerizable vinyl group in the monomer ends obtained by polymerizing a vinyl group. These can be copolymerized with the monomer S1 alone or in combination.

  In some embodiments, by including also in the polymer A a monomer unit common to the monomer unit contained in the polymer B, the mobility of the polymer B in the pressure-sensitive adhesive layer can be improved, and the adhesion increase ratio can be improved. . It is effective that the common monomer unit is a component that occupies 5% by weight or more of the total monomer units constituting the polymer B, 10% by weight or more (more preferably 20% by weight or more, for example 30% by weight or more) It is preferable that it is an ingredient which occupies. The ratio of the common monomer unit to the total monomer units constituting the polymer A may be, for example, 1% by weight or more, preferably 3% by weight or more, more preferably 5% by weight or more, and 7% by weight or more It may be When the ratio of the common monomer units to the total monomer units constituting the polymer A is high, the effect of improving the compatibility tends to be exhibited better. Further, in consideration of the balance with other properties, the ratio of the common monomer unit to the total monomer units constituting the polymer A may be 50% by weight or less, or 30% by weight or less. Non-limiting examples of monomers that can be preferably employed as common monomer units, MMA, BMA, 2EHMA, methyl acrylate (MA), BA, 2 EHA, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl Examples include (meth) acrylates and the like.

  The Mw of the polymer B is not particularly limited. The Mw of the polymer B may be, for example, 1,000 or more, or 5,000 or more. If the Mw of the polymer B is too low, the increase in adhesion may be insufficient. In some preferred embodiments, the Mw of the polymer B may be, for example, 10000 or more, 12000 or more, 15000 or more, 17000 or more, or 20000 or more. In addition, Mw of the polymer B may be, for example, 100,000 or less, and may be 70000 or less. If the Mw of the polymer B is too high, the initial tack may not be sufficiently suppressed. In some preferred embodiments, the Mw of polymer B may be, for example, 50000 or less, may be less than 50000, may be less than 40000, may be less than 35000, may be 30000 or less, may be 28000 or less, or 25000 or less May be. When the Mw of the polymer B is within the range of any of the upper limit and the lower limit described above, the compatibility and mobility in the pressure-sensitive adhesive layer can be easily adjusted to an appropriate range, and the initial low adhesiveness and adherend It becomes easy to implement | achieve the reinforcement film which makes compatible with the strong adhesiveness at the time of use at a high level.

The polymer B can be produced, for example, by polymerizing the above-described monomer by a known method such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, photopolymerization and the like.
The initiator used for the polymerization of the polymer B can be appropriately selected from conventionally known thermal polymerization initiators, photo polymerization initiators and the like according to the polymerization method. The polymerization initiators can be used alone or in combination of two or more. The thermal polymerization initiator and the photopolymerization initiator may be selected from the same materials as exemplified for the polymerization of the polymer A. In some embodiments, an azo polymerization initiator may be preferably employed.

  A chain transfer agent can be used to adjust the molecular weight of polymer B. Examples of chain transfer agents to be used include compounds having a mercapto group such as octyl mercaptan, lauryl mercaptan, t-nonyl mercaptan, t-dodecyl mercaptan, mercaptoethanol, α-thioglycerol, etc .; thioglycolic acid; methyl thioglycollate, Ethyl thioglycolate, propyl thioglycollate, butyl thioglycollate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, isooctyl thioglycolate, decyl thioglycollate, dodecyl thioglycolate, ethylene Thioglycolic acid esters such as thioglycolic acid ester of glycol, thioglycolic acid ester of neopentyl glycol, thioglycolic acid ester of pentaerythritol; And so forth. In some embodiments, thioglycolic acid esters may be preferably employed as chain transfer agents.

  The amount of the chain transfer agent used is not particularly limited, but usually 0.05 to 20 parts by weight, preferably 0.1 to 15 parts by weight of the chain transfer agent per 100 parts by weight of the monomer. More preferably, it is contained in an amount of 0.2 to 10 parts by weight. By adjusting the addition amount of the chain transfer agent in this manner, a polymer B having a suitable molecular weight can be obtained. In addition, a chain transfer agent can be used individually by 1 type or in combination of 2 or more types.

  Although not particularly limited, the use amount of the polymer B can be, for example, 0.1 parts by weight or more with respect to 100 parts by weight of the polymer A, and from the viewpoint of obtaining higher effects, 0.3 It is good also as a weight part or more, good also as a 0.4 weight part or more, and good also as 0.5 weight part or more. In some embodiments, the amount of polymer B used relative to 100 parts by weight of polymer A may be 1 part by weight or more, 2 parts by weight or more, or 3 parts by weight or more. The amount of polymer B used relative to 100 parts by weight of the polymer A may be, for example, 75 parts by weight or less, 60 parts by weight or less, or 50 parts by weight or less. In some embodiments, the amount of polymer B used can be, for example, 40 parts by weight or less, and 35 parts by weight or less in some embodiments, from the viewpoint of avoiding excessive reduction in the cohesive force of the pressure-sensitive adhesive layer 30 parts by weight or less or 25 parts by weight or less. From the viewpoint of obtaining higher adhesion after heating, in some embodiments, the amount of the polymer B used may be 20 parts by weight or less, 17 parts by weight or less, 15 parts by weight or less, 10 parts by weight It is good also as a part or less. In some embodiments of the reinforcing film disclosed herein, the amount of polymer B used relative to 100 parts by weight of polymer A may be, for example, less than 10 parts by weight, may be 8 parts by weight or less, and 5 parts by weight or less Alternatively, it may be less than 5 parts by weight, 4 parts by weight or less, or 3 parts by weight or less.

  The pressure-sensitive adhesive layer may optionally contain a polymer (optional polymer) other than the polymer A and the polymer B as long as the performance of the reinforcing film disclosed herein is not significantly impaired. The amount of such optional polymer used is usually 20% by weight or less of the entire polymer component contained in the pressure-sensitive adhesive layer, and may be 15% by weight or less or 10% by weight or less. In some embodiments, the amount of the optional polymer used may be 5% by weight or less, 3% by weight or less, or 1% by weight or less of the entire polymer component. The pressure-sensitive adhesive layer may contain substantially no polymer other than the polymer A and the polymer B.

(Crosslinking agent)
In the pressure-sensitive adhesive layer, a crosslinking agent may be used as needed for the purpose of adjusting the cohesion force and the like. As the crosslinking agent, crosslinking agents known in the field of pressure-sensitive adhesives can be used. For example, epoxy-based crosslinking agents, isocyanate-based crosslinking agents, silicone-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, silane-based crosslinking agents A crosslinking agent, an alkyl etherified melamine based crosslinking agent, a metal chelate based crosslinking agent and the like can be mentioned. In particular, isocyanate crosslinking agents, epoxy crosslinking agents, and metal chelate crosslinking agents can be suitably used. The crosslinking agents can be used singly or in combination of two or more.

  Specifically, examples of isocyanate-based crosslinking agents include tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenyl (meth) diisocyanate, hydrogenated diphenyl (meth) diisocyanate And tetramethyl xylylene diisocyanate, naphthalene diisocyanate, triphenyl (meth) triisocyanate, polymethylene polyphenyl isocyanate, and adducts thereof with polyols such as trimethylolpropane. Alternatively, a compound having at least one or more isocyanate groups and one or more unsaturated bonds in one molecule, specifically, 2-isocyanatoethyl (meth) acrylate, etc. is also used as an isocyanate-based crosslinking agent. Can. These can be used singly or in combination of two or more.

  Examples of epoxy crosslinking agents include bisphenol A, epoxy resins of epichlorohydrin type, ethylene glycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether, 1,6-hexanediol glycidyl ether, trimethylolpropane triol. Glycidyl ether, diglycidyl aniline, diamine glycidyl amine, N, N, N ', N'-tetraglycidyl-m-xylylenediamine and 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane etc. Can. These can be used singly or in combination of two or more.

  Examples of the metal chelate compound include aluminum, iron, tin, titanium, nickel and the like as a metal component, and acetylene, methyl acetoacetate, ethyl lactate and the like as a chelate component. These can be used singly or in combination of two or more.

  The amount used in the case of using the crosslinking agent is not particularly limited, and can be, for example, an amount exceeding 0 parts by weight with respect to 100 parts by weight of the polymer A. The amount of the crosslinking agent used can be, for example, 0.01 parts by weight or more, preferably 0.05 parts by weight or more, per 100 parts by weight of the polymer A. By increasing the amount of crosslinking agent used, higher cohesion tends to be obtained. In some embodiments, the use amount of the crosslinking agent relative to 100 parts by weight of the polymer A may be 0.1 parts by weight or more, 0.5 parts by weight or more, or even 1 part by weight or more Good. On the other hand, from the viewpoint of avoiding a decrease in tack due to excessive cohesion, the amount of the crosslinking agent used per 100 parts by weight of the polymer A is usually 15 parts by weight or less, and may be 10 parts by weight or less. It may be 5 parts by weight or less. If the amount of the crosslinking agent used is not too large, it may be advantageous from the viewpoint of making the use effect of the polymer B better by utilizing the fluidity of the pressure-sensitive adhesive.

  The art disclosed herein can be preferably practiced in the aspect of using at least an isocyanate-based crosslinking agent as the crosslinking agent. From the viewpoint of facilitating the realization of a reinforcing film having high cohesion after heating and a large adhesion increase ratio, in some embodiments, the amount of isocyanate crosslinking agent used is 100 parts by weight or less, for example, 5 parts by weight or less It may be 4 parts by weight or less, 3 parts by weight or less, less than 1 part by weight, 0.7 parts by weight or less, and 0.5 parts by weight or less. In some cases, the amount of the isocyanate-based crosslinking agent used may be, for example, 0.1 parts by weight or more, 0.3 parts by weight or more, 0.5 parts by weight or more, It may be 0 parts by weight or more.

Although not particularly limited, if the pressure-sensitive adhesive layer is used isocyanate crosslinking agent in a configuration that includes a hydroxyl group-containing monomer as a monomer unit, the amount W _OH of the hydroxyl group-containing monomer to the amount W _NCO of isocyanate crosslinking agent, The amount of W _OH / W _NCO can be 2 or more on a weight basis. Thus, by increasing the amount of the hydroxyl group-containing monomer to the isocyanate-based crosslinking agent, a crosslinked structure suitable for improving the adhesive strength increase ratio can be formed. In some embodiments, W _OH / W _NCO may be 3 or more, 5 or more, 10 or more, 20 or more, or even 30 or more. It may be 50 or more. The upper limit of W _OH / W _NCO is not particularly limited. W _OH / W _NCO may be, for example, 500 or less, 200 or less, or 100 or less.

  A crosslinking catalyst may be used to promote any of the crosslinking reactions described above more effectively. As a crosslinking catalyst, for example, a tin-based catalyst (in particular, dioctyl tin dilaurate) can be preferably used. The use amount of the crosslinking catalyst is not particularly limited, and can be, for example, about 0.0001 parts by weight to 1 part by weight with respect to 100 parts by weight of the polymer A.

A polyfunctional monomer can be used for the adhesive layer as needed. Multifunctional monomers can serve for purposes such as adjustment of cohesion by being used in place of or in combination with the above-mentioned crosslinking agents. For example, in the pressure-sensitive adhesive layer formed from a photocurable pressure-sensitive adhesive composition, a polyfunctional monomer can be preferably used.
Examples of multifunctional monomers include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,12-dodecane Diol di (meth) acrylate, trimethylol propane tri (meth) acrylate, tetramethylol methane tri (meth) acrylate, allyl (meth) acrylate, bi Le (meth) acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, urethane acrylate, butyl diol (meth) acrylate, hexyl di (meth) acrylate. Among them, trimethylolpropane tri (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and dipentaerythritol hexa (meth) acrylate can be suitably used. The polyfunctional monomers can be used alone or in combination of two or more.

  The amount of the polyfunctional monomer used varies depending on the molecular weight, the number of functional groups, etc., but normally, it is appropriate to be in the range of about 0.01 part by weight to 3.0 parts by weight with respect to 100 parts by weight of the polymer A . In some embodiments, the amount of multifunctional monomer used may be, for example, 0.02 parts by weight or more, or 0.03 parts by weight or more, with respect to 100 parts by weight of the polymer A. By increasing the amount of multifunctional monomer used, higher cohesion tends to be obtained. On the other hand, the amount of the polyfunctional monomer used may be 2.0 parts by weight or less, and even 1.0 part by weight or less with respect to 100 parts by weight of the polymer A, from the viewpoint of avoiding a decrease in tack due to excessive cohesion. It may well be 0.5 parts by weight or less. Not using too much amount of the polyfunctional monomer may be advantageous also from the viewpoint of making the use effect of the polymer B better by utilizing the fluidity of the adhesive.

(Tackifying resin)
The pressure-sensitive adhesive layer can optionally contain a tackifying resin. The tackifier resin is not particularly limited, and, for example, rosin-based tackifier resin, terpene-based tackifier resin, phenol-based tackifier resin, hydrocarbon-based tackifier resin, ketone-based tackifier resin, polyamide-based tackifier resin, Epoxy tackifying resins, elastomeric tackifying resins and the like can be mentioned. The tackifying resin can be used singly or in combination of two or more.

Examples of rosin-based tackifying resins include unmodified rosin (raw rosin) such as gum rosin, wood rosin, tall oil rosin, and modified rosin obtained by modifying these unmodified rosins by polymerization, disproportionation, hydrogenation, etc. In addition to polymerized rosins, stabilized rosins, disproportionated rosins, fully hydrogenated rosins, partially hydrogenated rosins, and other chemically modified rosins, various rosin derivatives may be mentioned.
Examples of the rosin derivatives include
Rosin phenolic resins obtained by thermally polymerizing a rosin (unmodified rosin, modified rosin, various rosin derivatives, etc.) with an acid catalyst and thermally polymerizing it;
Ester compounds of rosin obtained by esterifying unmodified rosin with alcohol (unmodified rosin ester), modified rosin such as polymerized rosin, stabilized rosin, disproportionated rosin, fully hydrogenated rosin, partially hydrogenated rosin, etc. Rosin ester-based resins such as ester compounds of modified rosin esterified by esterification (polymerized rosin ester, stabilized rosin ester, disproportionated rosin ester, fully hydrogenated rosin ester, partially hydrogenated rosin ester, etc.);
Unsaturated fatty acid modified rosin based resins modified with unsaturated fatty acids such as unmodified rosins and modified rosins (polymerized rosins, stabilized rosins, disproportionated rosins, fully hydrogenated rosins, partially hydrogenated rosins, etc.);
Unsaturated fatty acid modified rosin ester resin modified from rosin ester resin with unsaturated fatty acid;
Carboxyl group in unmodified rosin, modified rosin (polymerized rosin, stabilized rosin, disproportionated rosin, completely hydrogenated rosin, partially hydrogenated rosin, etc.), unsaturated fatty acid modified rosin resin and unsaturated fatty acid modified rosin ester resin Rosin alcohol resin with reduction treatment;
Examples include unmodified rosin, modified rosin, and metal salts of rosin resins (in particular, rosin ester resins) such as various rosin derivatives.

  Examples of terpene-based tackifying resins include terpene-based resins such as α-pinene polymers, β-pinene polymers, and dipentene polymers, and those terpene-based resins modified (phenol modification, aromatic modification, hydrogenation modification And modified terpene resins (eg, terpene phenol resins, styrene modified terpene resins, aromatic modified terpene resins, hydrogenated terpene resins, etc.) and the like.

  Examples of the phenol-based tackifying resin include condensates of various phenols (eg, phenol, m-cresol, 3,5-xylenol, p-alkylphenol, resorcin etc.) with formaldehyde (eg, alkylphenol-based resin, xylene formaldehyde) And resins such as resoles obtained by subjecting the above-mentioned phenols and formaldehyde to an addition reaction with an alkali catalyst, and novolaks obtained by subjecting the above-mentioned phenols and formaldehyde to a condensation reaction with an acid catalyst.

  Examples of hydrocarbon tackifying resins include aliphatic hydrocarbon resins, aromatic hydrocarbon resins, aliphatic cyclic hydrocarbon resins, aliphatic and aromatic petroleum resins (styrene-olefin copolymers, etc.) And various hydrocarbon resins such as aliphatic and alicyclic petroleum resins, hydrogenated hydrocarbon resins, coumarone resins, and coumarone indene resins.

  As a commercial item of the polymerization rosin ester which can be preferably used, the brand names "Pencel D-125", "Pencel D-135", "Pencel D-160", "Pencel KK", "Pencel" by Arakawa Chemical Industries, Ltd. are used. C "and the like, but is not limited thereto.

  As a commercial item of the terpene phenol-type resin which can be used preferably, the brand name "YS poly star S-145", "YS poly star G-125", "YS poly star N125", "YS poly star U-115" by Yashara Chemical Co., Ltd. are manufactured. Arakawa Chemical Industry Co., Ltd. trade name "Tamanor 803L", "Tamanor 901", Sumitomo Bakelite Co., Ltd. trade name "Sumilite resin PR-12603", etc. are exemplified, but not limited thereto.

  The content of the tackifier resin is not particularly limited, and can be set so as to exhibit appropriate adhesion performance depending on the purpose and application. The content of the tackifier resin (the total amount of two or more tackifier resins, if any, of the two or more tackifier resins) relative to 100 parts by weight of the polymer A can be, for example, about 5 to 500 parts by weight.

  As the tackifying resin, those having a softening point (softening temperature) of about 80 ° C. or more (preferably, about 100 ° C. or more, for example, about 120 ° C. or more) can be preferably used. With a tackifying resin having a softening point equal to or lower than the lower limit value described above, the initial low tackiness and the strong tackiness when using an adherend tend to be effectively improved. The upper limit of the softening point is not particularly limited, and may be, for example, about 200 ° C. or less (typically, 180 ° C. or less). In addition, the softening point of tackifying resin can be measured based on the softening point test method (ring and ball method) prescribed | regulated to JISK2207.

  In addition, the pressure-sensitive adhesive layer in the art disclosed herein is a leveling agent, a plasticizer, a softener, a coloring agent (dye, pigment, etc.), a filler, an antistatic agent, as long as the effects of the present invention are not significantly impaired. If necessary, known additives which can be used in the pressure-sensitive adhesive may be contained, such as anti-aging agents, ultraviolet light absorbers, antioxidants, light stabilizers, preservatives and the like.

  The pressure-sensitive adhesive layer constituting the reinforcing film disclosed herein may be a cured layer of the pressure-sensitive adhesive composition. That is, the pressure-sensitive adhesive layer is formed by appropriately applying (for example, applying) a pressure-sensitive adhesive composition such as a water dispersion type, a solvent type, a photocurable type, a hot melt type to a suitable surface, and then performing curing treatment appropriately. obtain. When two or more curing treatments (drying, crosslinking, polymerization, cooling, etc.) are carried out, these can be carried out simultaneously or in multiple stages. In a pressure-sensitive adhesive composition using a partially polymerized product of monomer components (acrylic polymer syrup), a final copolymerization reaction is typically performed as the above-mentioned curing treatment. That is, the partially polymerized product is subjected to a further copolymerization reaction to form a completely polymerized product. For example, if it is a photocurable pressure-sensitive adhesive composition, light irradiation is carried out. If necessary, curing treatment such as crosslinking or drying may be performed. For example, when it is necessary to dry with a photocurable pressure-sensitive adhesive composition, light curing may be performed after drying. In the case of a pressure-sensitive adhesive composition using a completely polymerized product, typically, a treatment such as drying (heat drying) or crosslinking is carried out as the curing treatment as necessary.

  The application of the pressure-sensitive adhesive composition can be carried out using, for example, a conventional coater such as a gravure roll coater, a reverse roll coater, a kiss roll coater, a dip roll coater, a bar coater, a knife coater, or a spray coater.

  The thickness of the pressure-sensitive adhesive layer is not particularly limited, and can be, for example, 1 μm or more. In some embodiments, the thickness of the pressure-sensitive adhesive layer may be, for example, 3 μm or more, 5 μm or more, 8 μm or more, 10 μm or more, 15 μm or more, 20 μm or more, or 20 μm or more. The increase in thickness of the pressure-sensitive adhesive layer tends to increase the adhesion after heating. This can be advantageous from the viewpoint of firmly integrating the adherend and the support base to exhibit a high reinforcing function. In some embodiments, the thickness of the pressure-sensitive adhesive layer may be, for example, 300 μm or less, 200 μm or less, 150 μm or less, 100 μm or less, 70 μm or less, or 50 μm or less, 40 μm Or less. If the thickness of the pressure-sensitive adhesive layer is not too large, it may be advantageous from the viewpoint of thinning the reinforcing film and preventing cohesive failure of the pressure-sensitive adhesive layer. In the case of a reinforcing film having a first pressure-sensitive adhesive layer and a second pressure-sensitive adhesive layer on the first surface and the second surface of the substrate, the thickness of the pressure-sensitive adhesive layer described above is at least the thickness of the first pressure-sensitive adhesive layer Can be applied to The thickness of the second pressure-sensitive adhesive layer can also be selected from the same range.

  Although not particularly limited, the gel fraction of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is usually suitably in the range of 20.0% to 99.0%, and 30.0% to 90. 0. It is desirable to be in the range of 0%. By setting the gel fraction in the above-mentioned range, it is possible to easily realize a reinforcing film in which the initial low tackiness and the strong tackiness at the time of using the adherend are compatible at a high level. The gel fraction is measured by the following method.

[Measurement of gel fraction]
About 0.1 g of a pressure-sensitive adhesive sample (weight Wg ₁ ) is wrapped with a porous polytetrafluoroethylene membrane (weight Wg ₂ ) having an average pore diameter of 0.2 μm in a drawstring shape, and the mouth is tied with a tacho yarn (weight Wg ₃ ). As the porous polytetrafluoroethylene membrane, a trade name "Nitoflon (registered trademark) NTF 1122" (Nitto Denko Corp., average pore diameter 0.2 μm, porosity 75%, thickness 85 μm) or an equivalent thereof is used. This packet is immersed in 50 mL of ethyl acetate and kept at room temperature (typically 23 ° C.) for 7 days to elute the sol (ethyl acetate soluble) in the adhesive outside the membrane. Then, the package is taken out, the ethyl acetate adhering to the outer surface is wiped off, the package is dried at 130 ° C. for 2 hours, and the weight (Wg ₄ ) of the package is measured. By substituting each value into the following equation, it is possible to calculate the gel fraction G _C of the pressure-sensitive adhesive.
Gel fraction G _C (%) = [(Wg _4- Wg _2- Wg ₃ ) / Wg ₁ ] × 100

  The reinforcing film disclosed herein is formed by, for example, bringing a liquid pressure-sensitive adhesive composition into contact with the first surface of a substrate, and curing the pressure-sensitive adhesive composition on the first surface to form a pressure-sensitive adhesive layer. Can be preferably produced by a method comprising: The curing of the pressure-sensitive adhesive composition may involve one or more of drying, crosslinking, polymerization, cooling and the like of the pressure-sensitive adhesive composition. Thus, according to the method of forming a pressure-sensitive adhesive layer by curing the liquid pressure-sensitive adhesive composition on the first surface of the substrate, the cured pressure-sensitive adhesive layer is attached to the first surface of the substrate. The anchorability of the pressure-sensitive adhesive layer to the substrate can be enhanced as compared to the method of arranging the pressure-sensitive adhesive layer on the first surface. By utilizing this, it is possible to preferably manufacture a reinforcing film in which the pressure-sensitive adhesive layer is fixed to the first surface of the substrate.

  In some embodiments, as a method of bringing the liquid pressure-sensitive adhesive composition into contact with the first surface of the substrate, a method in which the above-mentioned pressure-sensitive adhesive composition is directly applied to the first surface of the substrate can be employed. The second surface of the pressure-sensitive adhesive layer adheres to the first surface of the substrate by bringing the first surface (pressure-sensitive adhesive surface) of the pressure-sensitive adhesive layer cured on the first surface of the substrate into contact with the peeling surface. And, it is possible to obtain a reinforced film having a configuration in which the first surface of the pressure-sensitive adhesive layer is in contact with the peeling surface. As said peeling surface, the surface of a peeling liner, the base-material back surface etc. which were peel-treated can be utilized.

  Further, for example, in the case of a photocurable pressure-sensitive adhesive composition using a partially polymerized product of monomer components (acrylic polymer syrup), for example, after the pressure-sensitive adhesive composition is applied to a release surface, the applied adhesion The uncured pressure-sensitive adhesive composition is brought into contact with the first surface of the substrate by covering the first surface of the substrate with the agent composition, and in that state, between the first surface of the substrate and the peeling surface The pressure-sensitive adhesive layer may be formed by curing the pressure-sensitive adhesive composition which has been sandwiched by light irradiation.

  In addition, the method illustrated above does not limit the manufacturing method of the reinforcement film disclosed here. In the production of the reinforcing film disclosed herein, any appropriate method capable of fixing the second surface of the pressure-sensitive adhesive layer to the first surface of the substrate can be used singly or in combination of two or more. . For example, when the anchorability of the pressure-sensitive adhesive layer to the substrate can be sufficiently improved by a method such as providing an undercoat layer on the first surface of the substrate, the pressure-sensitive adhesive layer after curing is used as the first surface of the substrate The reinforcing film may be manufactured by a method of bonding to

<Supporting substrate>
As a support base material of the reinforcement film disclosed here, what contains various resin films as a base film may be used. Here, "resin film" means a non-porous structure and a resin film which is substantially free of bubbles (voidless). Therefore, the said resin film is the concept distinguished from a foam film and a nonwoven fabric. As the resin film, those which can be independently maintained in shape (self-supporting or independent) can be preferably used. The resin film may have a single-layer structure or a multilayer structure of two or more layers (for example, a three-layer structure).

  Examples of the resin material constituting the resin film include polyester, polyolefin, nylon 6, nylon 66, polyamide (PA) such as partially aromatic polyamide, polyimide (PI), polyamide imide (PAI), polyetheretherketone (PEEK) ), Fluorine resin such as polyether sulfone (PES), polyphenylene sulfide (PPS), polycarbonate (PC), polyurethane (PU), ethylene-vinyl acetate copolymer (EVA), polytetrafluoroethylene (PTFE), acrylic resin And resins such as polyacrylate, polystyrene, polyvinyl chloride and polyvinylidene chloride can be used. The resin film may be formed of a resin material containing one kind of such a resin alone, or may be formed of a resin material in which two or more kinds are blended. Good. The resin film may be unstretched or may be stretched (for example, uniaxially stretched or biaxially stretched).

  Preferred examples of the resin material constituting the resin film include polyester resins, polyimide resins, PPS resins and polyolefin resins. Here, the polyester-based resin refers to a resin containing polyester at a ratio of more than 50% by weight. Similarly, a polyimide resin refers to a resin containing polyimide in a proportion exceeding 50% by weight, a PPS resin refers to a resin containing PPS in a proportion exceeding 50% by weight, and a polyolefin resin refers to a polyolefin Refers to resins containing more than 50% by weight.

  As the polyester resin, typically, a polyester resin containing, as a main component, a polyester obtained by polycondensation of a dicarboxylic acid and a diol is used.

  As a dicarboxylic acid which comprises the said polyester, phthalic acid, isophthalic acid, a terephthalic acid, 2-methylterephthalic acid, 5-sulfoisophthalic acid, 4,4'- diphenyl dicarboxylic acid, 4,4'- diphenyl ether dicarboxylic acid, for example 4,4′-diphenyl ketone dicarboxylic acid, 4,4′-diphenoxy ethane dicarboxylic acid, 4,4′-diphenyl sulfone dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 1,5-naphthalene dicarboxylic acid, Aromatic dicarboxylic acids such as 6-naphthalenedicarboxylic acid and 2,7-naphthalenedicarboxylic acid; alicyclic dicarboxylic acids such as 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid Malonic acid, succinic acid, glutaric acid, adipic acid, Aliphatic dicarboxylic acids such as malic acid, suberic acid, azelaic acid, sebacic acid and dodecanoic acid; unsaturated dicarboxylic acids such as maleic acid, maleic anhydride and fumaric acid; derivatives thereof (for example, the above dicarboxylic acids such as terephthalic acid) And lower alkyl esters of These can be used singly or in combination of two or more. Aromatic dicarboxylic acids are preferred from the viewpoint of strength and the like. Among them, preferred dicarboxylic acids include terephthalic acid and 2,6-naphthalene dicarboxylic acid. For example, 50% by weight or more (for example, 80% by weight or more, typically 95% by weight or more) of dicarboxylic acids constituting the above-mentioned polyester is terephthalic acid, 2,6-naphthalenedicarboxylic acid or a combination thereof Is preferred. The dicarboxylic acid may consist essentially of only terephthalic acid, substantially only 2,6-naphthalenedicarboxylic acid, or substantially only terephthalic acid and 2,6-naphthalenedicarboxylic acid.

  Examples of the diol constituting the above polyester include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,4-butanediol, Aliphatic diols such as 1,6-hexanediol, 1,8-octanediol, polyoxytetramethylene glycol and the like; 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,1-cyclohexanedimethylol, 1,4 Cycloaliphatic diols such as cyclohexane dimethylol, xylylene glycol, 4,4′-dihydroxybiphenyl, 2,2-bis (4′-hydroxyphenyl) propane, bis (4-hydroxyphenyl) sul Aromatic diols such emissions; and the like. These can be used singly or in combination of two or more. Among them, aliphatic diols are preferable from the viewpoint of transparency and the like, and ethylene glycol is particularly preferable. The proportion of the aliphatic diol (preferably ethylene glycol) in the diol constituting the polyester is preferably 50% by weight or more (eg, 80% by weight or more, typically 95% by weight or more). The diol may consist essentially of ethylene glycol only.

  Specific examples of polyester resins include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polybutylene naphthalate and the like.

  As a polyolefin resin, it is possible to use one type of polyolefin alone or a combination of two or more types of polyolefins. The polyolefin may be, for example, a homopolymer of α-olefin, a copolymer of two or more α-olefins, a copolymer of one or more α-olefins and another vinyl monomer, and the like. Specific examples thereof include ethylene-propylene copolymers such as polyethylene (PE), polypropylene (PP), poly-1-butene, poly-4-methyl-1-pentene, ethylene-propylene rubber (EPR), ethylene-propylene- A butene copolymer, an ethylene-butene copolymer, an ethylene-vinyl alcohol copolymer, an ethylene-ethyl acrylate copolymer, etc. are mentioned. Both low density (LD) and high density (HD) polyolefins can be used. Examples of polyolefin resin films include non-oriented polypropylene (CPP) film, biaxially oriented polypropylene (OPP) film, low density polyethylene (LDPE) film, linear low density polyethylene (LLDPE) film, medium density polyethylene (MDPE) A film, a high density polyethylene (HDPE) film, a polyethylene (PE) film in which two or more polyethylenes (PE) are blended, a PP / PE blend film in which polypropylene (PP) and polyethylene (PE) are blended, and the like can be mentioned.

  Commercially available polyimide resin films include, for example, trade name "Neoprim" (S grade, H grade, R grade etc.) manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name "Kapton" (H type, V manufactured by Toray Dupont Co., Ltd.) (Type, VN type etc.), trade name “UPILEX” (S type, RN type etc.) manufactured by Ube Industries, Ltd. trade name “Apical” (AH type, NPH type etc.) manufactured by Kaneka, trade name manufactured by Toray Industries, Inc. "Kapton 100H" etc. are mentioned.

  Specific examples of the resin film that can be preferably used as the base film of the reinforcing film disclosed herein include PET film, PEN film, PPS film, PEEK film, CPP film and OPP film. Examples of preferred base films from the viewpoint of strength and dimensional stability include PET films, PEN films, PPS films and PEEK films. PET films and PPS films are particularly preferred from the viewpoint of the availability of the substrate and the like, and PET films are particularly preferred.

  For resin films, known as light stabilizers, antioxidants, antistatic agents, colorants (dyes, pigments, etc.), fillers, slip agents, antiblocking agents, etc. to the extent that the effects of the present invention are not significantly impaired. The additives of the above can be blended as needed. The compounding amount of the additive is not particularly limited, and can be appropriately set according to the application of the reinforcing film and the like.

  The method for producing the resin film is not particularly limited. For example, conventionally known general resin film molding methods such as extrusion molding, inflation molding, T-die cast molding, calendar roll molding and the like can be appropriately adopted.

  The substrate may be substantially composed of such a base film. Alternatively, the substrate may include an auxiliary layer in addition to the base film. Examples of the auxiliary layer include an optical property adjusting layer (for example, a colored layer, an antireflection layer), a print layer or a laminate layer for giving a desired appearance to a substrate, an antistatic layer, an undercoat layer, a release layer And the like.

  The thickness of the substrate constituting the reinforcing film disclosed herein may be, for example, more than 25 μm, and typically 30 μm or more. The thickness of the substrate is preferably 35 μm or more, may be 40 μm or more, may be 50 μm or more (eg, more than 50 μm), may be 60 μm or more, and may be 70 μm or more. . Thicker substrates tend to exhibit higher reinforcement performance. The reinforcing film disclosed herein can also be suitably carried out in an embodiment in which the thickness of the substrate is 90 μm or more, or 100 μm or more, or 120 μm or more. The upper limit of the thickness of the substrate is not particularly limited. In some embodiments, the thickness of the substrate may be, for example, 500 μm or less, may be 300 μm or less, may be 250 μm or less, or 200 μm, from the viewpoint of handleability and processability of the reinforcing film. It may be the following. In some embodiments, the thickness of the substrate may be, for example, 160 μm or less, may be 130 μm or less, and 100 μm or less, from the viewpoint of reducing the size and weight of the product to which the reinforcing film is applied. It may be 90 μm or less, 75 μm or less, or 60 μm or less.

  On the first surface of the substrate, conventionally known surfaces such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, acid treatment, alkali treatment, formation of an undercoat layer by application of an undercoat (primer), etc. Processing may be performed. Such surface treatment may be treatment for improving the anchorability of the pressure-sensitive adhesive layer to the substrate. That is, the surface treatment may serve to facilitate obtaining a reinforcing film in which the second surface of the pressure-sensitive adhesive layer is fixed to the first surface of the substrate. The above surface treatments can be applied alone or in combination. The composition of the primer used to form the undercoat layer is not particularly limited, and can be appropriately selected from known ones. The thickness of the undercoat layer is not particularly limited, but is usually about 0.01 μm to 1 μm, and preferably about 0.1 μm to 1 μm. Examples of other treatments that may be applied to the first surface of the substrate as required include antistatic layer formation treatment, colored layer formation treatment, and printing treatment.

  When the reinforcing film disclosed herein is in the form of a single-sided pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer only on the first surface of the substrate, the second surface of the substrate is subjected to peeling treatment or antistatic treatment as necessary. The surface treatment conventionally known, such as, may be given. For example, in a reinforcing film in a form (roll form, laminated form, etc.) using the second surface of the substrate as a peeling surface in contact with the adhesive surface, the water contact angle of the second surface is 100 degrees or more, or this specification In order to adjust to the more preferable range disclosed by the above, the second surface can be subjected to a peeling treatment. As a typical example of the said peeling process, the process which forms the peeling layer by a peeling process agent in the 2nd surface of a base material is mentioned. In addition, in the reinforcing film in which the release surface of the release liner other than the substrate is used as the release surface in contact with the adhesive surface, the printability on the second surface is improved on the second surface of the substrate. In order to reduce the light reflectivity and to improve the overlapping property, treatments such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, acid treatment, alkali treatment and the like may be performed.

  When the reinforcing film disclosed herein has the first pressure-sensitive adhesive layer on the first surface of the substrate and is in the form of a double-sided pressure-sensitive adhesive sheet having the second pressure-sensitive adhesive layer on the second surface of the substrate, The second surface may optionally be subjected to the same surface treatment as exemplified above as the surface treatment that can be applied to the first surface of the substrate. Such surface treatment may be surface treatment for enhancing the anchorability of the second pressure-sensitive adhesive layer to the substrate. The surface treatment to be applied to the first surface of the substrate and the surface treatment to be applied to the second surface may be the same as or different from each other.

<Reinforcement film>
The reinforcing film disclosed herein has the second surface of the pressure-sensitive adhesive layer adhered to the first surface of the substrate. The above-mentioned adhesion is a pressure-sensitive adhesive to the extent that the reinforcing function by the above-mentioned reinforcing film is not impaired by the peeling at the interface between the pressure-sensitive adhesive layer and the support substrate in the reinforcing film in which the adhesive strength is increased after being attached to the adherend. It says that a layer shows sufficient anchorability to a support base material. Even if the adhesion of the adhesive surface to the adherend after adhesion of the reinforcing film to the adherend is increased, the adherend and the support base of the reinforcing film in which the anchoring property of the pressure-sensitive adhesive layer to the support substrate is insufficient. The material can not be firmly integrated, and the reinforcing performance of the adherend by the reinforcing film tends to be impaired. The reinforcing film in which the second surface of the pressure-sensitive adhesive layer is fixed to the first surface of the substrate can effectively contribute to the reinforcement of the adherend. As one preferable example of the reinforcing film in which the second surface of the pressure-sensitive adhesive layer is fixed to the first surface of the substrate, after being attached to the adherend, at least 5 N / 25 mm, preferably 10 N / 25 mm or more, more preferably When the film is peeled from the adherend while exhibiting an adhesive strength of 15 N / 25 mm or more (180 ° peel strength measured at a peeling angle of 180 ° and a tensile speed of 300 mm / min), A reinforcing film which does not cause peeling (ditch failure) between the two surfaces and the first surface of the support substrate can be mentioned. For example, in the case of a reinforcing film which has a tackiness after heating of 15 N / 25 mm or more and no anchorage fracture occurs at the measurement of tackiness after heating, the second surface of the pressure-sensitive adhesive layer adheres to the first surface of the substrate This is a preferred example corresponding to the reinforcing film being used.

  As a method of obtaining the reinforcing film in which the second surface of the pressure-sensitive adhesive layer is adhered to the first surface of the substrate, the liquid pressure-sensitive adhesive composition is cured on the first surface of the substrate as described above The method of forming an agent layer, the method of surface-treating which raises the anchoring property of an adhesive layer on the 1st surface of a base material, etc. are mentioned. The anchorability of the pressure-sensitive adhesive layer to the substrate can also be improved by the selection of the material of the substrate and the selection of the composition of the pressure-sensitive adhesive. In addition, by applying a temperature higher than room temperature to the reinforcing film having the pressure-sensitive adhesive layer on the first surface of the substrate, the anchorability of the pressure-sensitive adhesive layer to the substrate can be enhanced. The temperature applied to enhance anchoring may be, for example, about 35 ° C. to 80 ° C., may be about 40 ° C. to 70 ° C. or more, and may be about 45 ° C. to 60 ° C.

  The reinforcing film disclosed herein has a form in which the first surface (adhesive surface) of the pressure-sensitive adhesive layer is in contact with a peeling surface having a water contact angle of 100 degrees or more. By this, the influence which the preservation | save conditions of a reinforcement film have on the performance of this reinforcement film can be reduced effectively. The peeling surface with a water contact angle of 100 degrees or more has low polarity, so by storing the reinforcing film in a state where the peeling surface is in contact with the adhesive surface, regardless of the storage conditions (for example, to the adherend In the pasted state, even if the adhesive is stored in a temperature range where adhesion increases, uneven distribution of polymer B on the surface of the pressure-sensitive adhesive layer is suitably promoted or maintained, and light peelability at the initial stage of bonding (low adhesion) Is considered to be expressed. Then, after the adhesive surface of the reinforcing film is separated from the release surface and attached to the adherend, that is, in the state where the adhesive surface is in contact with the adherend, the polarity of the adherend is generally the release surface. It is considered that the amount of polymer B present on the surface of the pressure-sensitive adhesive decreases due to mass transfer or molecular motion in the pressure-sensitive adhesive layer with heat or aging, and the adhesion is thus greatly increased. However, the scope of the present invention is not limited to this.

The water contact angle may be measured according to JIS R 3257: 1999 using a commercially available contact angle measuring device (droplet method). For example, the water contact angle can be measured under the following conditions. The measurement is preferably performed five times, and the average value is preferably adopted (n = 5). The same method is adopted for the examples described later.
[Water contact angle measurement conditions]
Measuring device: Contact angle measuring device DropMaster DM700 (manufactured by Kyowa Interface Science Co., Ltd.)
Measurement atmosphere: 23 ° C, 50% RH
Measurement liquid: Distilled water Measurement time: After landing 1500 ms

  In some embodiments, the water contact angle of the release surface in contact with the adhesive surface may be, for example, more than 100 degrees, 102 degrees or more, or 105 degrees or more. The upper limit of the water contact angle of the peeling surface is not particularly limited, but may be, for example, 130 degrees or less, 120 degrees or less, 115 degrees or less, or 110 degrees or less from the viewpoint of availability of materials, etc. . For example, a peeling surface having a water contact angle of 100 degrees or more and 110 degrees or less can be preferably employed.

  In some aspects of the reinforcement film disclosed herein, the release surface may be the surface of a release liner that is different from the support substrate. The release liner is not particularly limited, and, for example, a release liner having a release layer on the surface of a liner substrate such as a resin film or paper (which may be a paper laminated with a resin such as polyethylene), a fluorine polymer A release liner made of a resin film formed of a low adhesive material such as (polytetrafluoroethylene or the like) or a polyolefin resin (polyethylene, polypropylene or the like) can be used. A release liner having a release layer on the surface of the liner substrate is preferred because a release surface having a large water contact angle is easily obtained. A resin film is preferable as the above-mentioned liner base material because it is excellent in surface smoothness. For example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyester film (PET film, PBT film etc.), polyurethane film, ethylene-vinyl acetate copolymer A release liner having a release layer on the surface of a resin film such as a polymer film can be preferably employed.

  The reinforcing film whose release surface in contact with the adhesive surface is the surface of the release liner can be grasped as a component of a release film with a release liner including the reinforcing film and the release liner providing the release surface. Accordingly, this specification may provide a release liner-provided reinforcement film comprising any of the reinforcement films disclosed herein and a release liner having a release surface that abuts the adhesive surface of the reinforcement film.

  The thickness of the release liner is not particularly limited, but usually about 5 μm to 200 μm is appropriate. When the thickness of the release liner is in the above range, it is preferable because the bonding workability to the pressure-sensitive adhesive layer and the peeling workability from the pressure-sensitive adhesive layer are excellent. In some embodiments, the thickness of the release liner may be, for example, 10 μm or more, 20 μm or more, 30 μm or more, or 40 μm or more. The thickness of the release liner may be, for example, 100 μm or less, or 80 μm or less, from the viewpoint of facilitating peeling from the pressure-sensitive adhesive layer. The release liner may be subjected to known antistatic treatment such as coating type, kneading type, vapor deposition type and the like, as necessary.

  In some aspects of the reinforcing film disclosed herein, the release surface may be the second surface of the support substrate. For example, by providing a release layer on the surface of the base film described above, the second surface of the support base whose water contact angle is adjusted to 100 degrees or more can be used as a release surface to be brought into contact with the adhesive surface.

  For forming the above-mentioned release layer, for example, known release treatment agents such as silicone-based release treatment agents, long-chain alkyl-based release treatment agents, olefin-based release treatment agents, fluorine-based release treatment agents, fatty acid amide-based release treatment agents, etc. Can be used. Among them, silicone-based release agents are preferred. According to the release layer formed of the silicone-based release treatment agent, the temperature range in which the reinforcing film before use (before being attached to the adherend) is higher than room temperature as compared to the release layer formed of other release treatment agents It is possible to suppress the increase in initial cohesion due to storage at a higher level. For example, the initial tack can be kept low even if the reinforcing film before use is stored at a higher temperature and / or a longer temperature range above room temperature.

  The element ratio (atomic%) of silicon atoms (Si) on the surface of the release layer is calculated by measuring the surface of the release layer formed by the silicone release agent by X-ray photoelectron spectroscopy (ESCA) Can. In some embodiments, the elemental ratio of Si on the surface of the release layer may be, for example, 10 atomic% or more, 15 atomic% or more, or 20 atomic% or more. The elemental ratio of Si is usually 40 atomic% or less, preferably 30 atomic% or less, or 25 atomic% or less. In the reinforcing film disclosed herein, a peeling surface having a peeling layer having an atomic ratio (atomic%) of Si on the surface of 20 atomic% or more and 25 atomic% or less can be preferably adopted as a peeling surface for bringing the adhesive surface into contact. . The measurement of the elemental ratio of Si on the release layer surface based on ESCA can be performed by the method described in the examples described later.

  In some embodiments, the release layer may be a release layer formed by a non-silicone release treatment agent. The release surface having such a release layer is preferably used, for example, as a release surface to be brought into contact with the adhesive surface of a reinforcing film that can be used in the field where adhesion of uncured silicone release treatment agent to adherend is concerned. It can be adopted. Specific examples of non-silicone release agents include long-chain alkyl release agents, olefin release agents, and fluorine release agents. As a preferred non-silicone release treatment agent, a long chain alkyl release treatment agent and an olefin release treatment agent are exemplified. Among them, long-chain alkyl-based release agents are preferable.

  The reinforcing film disclosed herein is stored, for example, in a temperature range higher than room temperature regardless of the storage conditions of the reinforcing film, because the adhesive surface is in contact with the peeling surface having a water contact angle of 100 degrees or more. Even in this case, it is possible to keep the peeling force from the peeling surface of the pressure-sensitive adhesive surface (hereinafter also referred to as “liner peeling force” or simply “peeling force”) low. If the peeling force is too high, problems such as an increase in work load at the time of affixing the reinforcing film to the adherend and a decrease in surface roughness of the adhesive surface by peeling the adhesive surface from the peeling surface occur. obtain. By bringing the peeling surface having a water contact angle of 100 degrees or more into contact with the adhesive surface, it is possible to effectively suppress the increase in peeling force during storage of the reinforcing film. According to the peeling surface which has a peeling layer by a silicone type peeling processing agent, it exists in the tendency for the outstanding outstanding peeling force rise inhibitory effect to be exhibited.

  The thickness of the release layer is not particularly limited, but is usually about 0.01 μm to 1 μm, preferably about 0.1 μm to 1 μm. The formation method of a peeling layer is not specifically limited, The well-known method according to the kind etc. of the peeling process agent to be used can be employ | adopted suitably.

The thickness of the reinforcing film disclosed herein can be, for example, greater than 30 μm. From the viewpoint of enhancing the reinforcing effect, in some embodiments, the thickness of the reinforcing film may be, for example, 50 μm or more, 60 μm or more, 80 μm or more, 100 μm or more, or 130 μm or more. The upper limit of the thickness of the reinforcing film is not particularly limited. The thickness of the reinforcing film may be, for example, 1000 μm or less, 600 μm or less, 350 μm or less, or 250 μm or less. In some embodiments, the thickness of the reinforcing film may be, for example, 200 μm or less, and may be 175 μm or less, from the viewpoint of reducing the size, weight and thickness of the product to which the reinforcing film is applied. It may be 140 μm or less, 120 μm or less, 100 μm or less (for example, less than 100 μm), or 80 μm or less.
In addition, the thickness of a reinforcement film means the thickness of the part affixed on a to-be-adhered body. For example, in the reinforcing film 1 configured as shown in FIG. 1, the thickness refers to the thickness from the adhesive surface 21A of the reinforcing film 1 to the second surface 10B of the substrate 10 and does not include the thickness of the release liner 31.

  The reinforcing film disclosed herein can be suitably implemented in a mode in which the thickness Ts of the support substrate is larger than the thickness Ta of the pressure-sensitive adhesive layer. That is, it is preferable that Ts / Ta be greater than one. Although not particularly limited, Ts / Ta may be, for example, 1.1 or more, 1.2 or more, 1.5 or more, or 1.7 or more. It is also good. Due to the increase in Ts / Ta, good reinforcement performance tends to be easily exhibited even if the thickness of the reinforcing film is reduced. In some embodiments, Ts / Ta may be 2 or more (e.g., more than 2), 3 or more, or 4 or more. Further, Ts / Ta may be, for example, 50 or less, and may be 20 or less. Ts / Ta may be, for example, 10 or less, and may be 8 or less, from the viewpoint of facilitating high adhesion after heating even if the thickness of the reinforcing film is reduced.

<Characteristics of reinforcement film>
The reinforcing film disclosed herein has an initial ratio of adhesive strength N2 (adhesive strength after heating) to adhesive strength N1 (initial adhesive strength), that is, an adhesive strength increase ratio (N2 / N1) of 10 or more. It exhibits low adhesion and can exhibit strong adhesion to the adherend when the adherend is used. By this, favorable rework property and high reinforcement performance can be compatible suitably. From the viewpoint of obtaining higher effects, in some embodiments, the adhesive strength increase ratio is preferably 15 or more, 18 or more, 20 or more, or 25 or more. The upper limit of the adhesive strength increase ratio is not particularly limited, but may be, for example, 100 or less, 80 or less, or 60 or less from the viewpoint of easiness of production of the reinforcing film and economy. The reinforcing film disclosed herein can be suitably implemented in an aspect in which the adhesion increase ratio is, for example, 10 or more and 80 or less, or 15 or more and 60 or less.

  The above adhesion increase ratio is defined as the ratio of adhesion after heating [N / 25 mm] to initial adhesion [N / 25 mm], and the initial adhesion is crimped to a stainless steel (SUS) plate as an adherend The sample is left for 30 minutes in an environment of 23 ° C. and 50% RH, and then grasped by measuring the peeling strength at 180 ° under the conditions of a peeling angle of 180 ° and a tensile speed of 300 mm / min. After heating, the adhesive strength [N / 25 mm] is crimped to a SUS plate as an adherend, heated at 80 ° C for 5 minutes, and then left in an environment of 23 ° C and 50% RH for 30 minutes, and then the peeling angle It is grasped by measuring the 180 ° peel strength under the conditions of 180 ° and a tensile speed of 300 mm / min. As the adherend, a SUS304BA plate is used for both initial adhesion and adhesion after heating. The measurement methods of the initial tackiness and the post-heating tackiness are applied to any of the first tacky surface and the second tacky surface. More specifically, the initial tack and the tack after heating can be measured according to the methods described in the examples described later.

  Although not particularly limited, in some aspects of the reinforcement film disclosed herein, the initial adhesion of the reinforcement film may be, for example, 2.0 N / 25 mm or less, and even less than 1.5 N / 25 mm. It may be 1.2 N / 25 mm or less, 1.0 N / 25 mm or less, or 0.8 N / 25 mm or less. Low initial tack is preferable from the viewpoint of reworkability. The lower limit of the initial tack is not particularly limited, and, for example,. It may be 0.01 N / 25 mm or more. It is appropriate that the initial adhesive strength is usually 0.1 N / 25 mm or more from the viewpoint of the workability of bonding to the adherend and the prevention of positional deviation before the adhesive strength is increased. In some embodiments, the initial tack may be, for example, 0.2 N / 25 mm or more, 0.3 N / 25 mm or more, 0.4 N / 25 mm or more, 0.5 N / 25 mm or more.

  Although not particularly limited, in some embodiments of the reinforcement film disclosed herein, the adhesion after heating of the reinforcement film may be, for example, 5.0 N / 25 mm or more, 7.0 N / 25 mm or more 10 N / 25 mm or more, 13 N / 25 mm or more, 15 N / 25 mm or more, or 17 N / 25 mm or more. It is preferable from the viewpoint of reinforcing performance improvement to exhibit higher adhesion after heating. The upper limit of adhesion after heating is not particularly limited. The adhesive strength after heating may be, for example, 50 N / 25 mm or less, 40 N / 25 mm or less, 35 N / 25 mm or less, in some embodiments from the viewpoint of easiness of production and economy of the reinforcing film. It may be 25 mm or less.

  The adhesion after heating of the reinforcing film disclosed herein represents one characteristic of the reinforcing film, and does not limit the mode of use of the reinforcing film. In other words, the usage mode of the reinforcing film disclosed herein is not limited to the mode in which heating at 80 ° C. for 5 minutes is performed, and for example, room temperature range (usually 20 ° C. to 30 ° C., typically 23 ° C. to 25) It can be used also in the aspect which does not perform especially the process heated more than ° C). Also in this mode of use, the adhesive strength is increased in the long term, and strong bonding can be realized. In addition, the reinforcing film disclosed herein can promote an increase in tackiness by performing a heat treatment at an arbitrary timing after pasting. The heating temperature in the heat treatment is not particularly limited, and can be set in consideration of workability, economy, heat resistance of a base of a reinforcing film, an adherend, and the like. The heating temperature may be, for example, less than 150 ° C., 120 ° C. or less, 100 ° C. or less, 80 ° C. or less, or 70 ° C. or less. The heating temperature may be, for example, 35 ° C. or more, 50 ° C. or more, or 60 ° C. or more, may be 80 ° C. or more, or 100 ° C. or more. With higher heating temperatures, the tack can be increased by a shorter treatment. The heating time is not particularly limited, and may be, for example, 1 hour or less, 30 minutes or less, 10 minutes or less, or 5 minutes or less. Alternatively, heat treatment may be performed for a longer period of time as long as significant thermal deterioration does not occur in the reinforcing film or the adherend. Note that the heat treatment may be performed at one time or may be performed plural times.

  In some embodiments, the peeling force from the peeling surface of the adhesive surface of the reinforcing film is usually 1.5 N / 25 mm or less, preferably 1.0 N / 25 mm or less, more preferably 0. It is 5 N / 25 mm or less, more preferably 0.3 N / 25 mm or less. It is preferable that the peeling force is low from the viewpoint of reducing the work load when peeling the peeling surface from the adhesive surface and maintaining the smoothness of the adhesive surface. In some embodiments, the peeling force may be, for example, 0.2 N / 25 mm or less, 0.1 N / 25 mm or less, 0.08 N / 25 mm or less, or 0.06 N / 25 mm or less. In addition, the peeling force may be, for example, 0.005 N / 25 mm or more, from the viewpoint of suppressing an event in which the adhesive surface is unintentionally lifted from the peeling surface before attaching the reinforcing film to the adherend. .01 N / 25 mm may be sufficient, 0.015 N / 25 mm or more may be sufficient.

  According to the technology disclosed herein, the peeling force from the peeling surface of the adhesive surface is 2 after storage for 7 days under conditions of 60 ° C. and 90% RH (hereinafter, also referred to as “storage under Condition 1”). A reinforcing film may be provided which is less than 0 N / 25 mm. In some embodiments, the peeling force after storage under the above condition 1 may be, for example, 1.5 N / 25 mm or less, 1.0 N / 25 mm or less, 0.5 N / 25 mm or less, 0.3 N / 25 mm or less, 0.1 N / 25 mm or less, or 0.08 N / 25 mm or less. The peeling force after storage under the above condition 1 may be, for example, 0.005 N / 25 mm or more, may be 0.01 N / 25 mm, or 0.015 N / 25 mm or more. The reinforcing film having a small ratio of the peeling force after storage to the peeling force after storage under the above condition 1 is preferable because the variation of the peeling performance due to storage is small.

  The peeling force after storage under the above condition 1 is preferably 5 times or less (for example, 0.5 times or more and 5 times or less) of the peeling force before storage, and more preferably 3 times or less. In some embodiments, the peel force after storage according to condition 1 above may be 3 times or less, 2 times or less, 1.5 times or less, or 1.3 times or less of the peel force before storage. In addition, the difference between the peel force after storage and the peel force before storage under the above condition 1 is preferably 1.0 N / 25 mm or less, 0.5 N / 25 mm or less, 0.1 N / 25 mm or less, 0.05 N It may be / 25 mm or 0.03 N / 25 mm or less. The reinforcing film having a small difference between the peel force after storage and the peel force before storage under the above condition 1 is preferable because the variation of the peel performance due to storage is small.

  According to the technology disclosed herein, the peel strength from the adhesive surface is 2.0 N / 25 mm after storage for 7 days at 85 ° C. (hereinafter, also referred to as “storage under condition 2”). The following reinforcing film may be provided. In some embodiments, the peeling force after storage under condition 2 may be, for example, 1.5 N / 25 mm or less, 1.0 N / 25 mm or less, 0.5 N / 25 mm or less, 0.3 N / 25 mm or less, 0.1 N / 25 mm or less, or 0.08 N / 25 mm or less. In addition, the peeling force after storage under the above condition 2 may be, for example, 0.005 N / 25 mm or more, may be 0.01 N / 25 mm, or 0.015 N / 25 mm or more. The reinforcing film having a small ratio of the peeling force after storage to the peeling force after storage under the above condition 2 is preferable because the variation of the peeling performance due to storage is small.

  The peeling force after storage under the above condition 2 is preferably 5 times or less (for example, 0.5 times or more and 5 times or less) of the peeling force before storage, and more preferably 3 times or less. In some embodiments, the peel force after storage according to Condition 2 may be 3 times or less, 2 times or less, 1.5 times or less, or 1.3 times or less of the peel force before storage. In addition, the difference between the peel force after storage and the peel force before storage under the above condition 2 is preferably 1.0 N / 25 mm or less, 0.5 N / 25 mm or less, 0.1 N / 25 mm or less, 0.05 N It may be / 25 mm or 0.03 N / 25 mm or less. The reinforcing film having a small difference between the peeling force after storage and the peeling force before storage under the above condition 2 is preferable because the variation of the peeling performance upon storage is small.

  According to some aspects of the technology disclosed herein, after storage under Condition 1 above, a reinforcement having a tenacity increase ratio of 10 or more, or meeting any other preferred tenacity increase ratio described above A film may be provided. The adhesive strength increase ratio of the reinforcing film after storage under the above condition 1 may be, for example, about 0.8 times to 3 times the adhesive power increase ratio before storage, and about 1.0 times to 2.5 times. It may be about 1.1 times to 2.5 times, or about 1.2 times to 2.0 times.

  According to some aspects of the technology disclosed herein, a reinforcement having an tenacity increase ratio of 10 times or more, or a storage condition meeting the above other preferred conditions described above after storage under condition 2 A film may be provided. The adhesive strength increase ratio of the reinforcing film after storage under the above condition 2 may be, for example, about 0.8 times to 3 times the adhesive power increase ratio before storage, or even about 1.0 times to 2.5 times. It may be about 1.1 times to 2.5 times, or about 1.2 times to 2.0 times.

  The reinforcing film disclosed herein comprises a first pressure-sensitive adhesive layer provided on the first surface of the substrate and a second pressure-sensitive adhesive layer provided on the second surface of the substrate (ie, both surfaces When it is a form of adhesive reinforcement film, the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer may have the same configuration or different configurations. When the configurations of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer are different, the difference may be, for example, a difference in composition or a difference in structure (thickness, surface roughness, formation range, formation pattern, etc.). In the double-sided adhesive reinforcing film, at least the second surface of the first pressure-sensitive adhesive layer adheres to the first surface of the supporting substrate, and the first surface (first pressure-sensitive adhesive surface) of the first pressure-sensitive adhesive layer has a water contact angle The characteristic of the second pressure-sensitive adhesive layer side is not particularly limited as long as it contacts the peeling surface of 100 degrees or more and the adhesive strength increase ratio of the first pressure-sensitive adhesive surface is 10 or more. For example, the second pressure-sensitive adhesive layer may be a pressure-sensitive adhesive layer containing no polymer B. In addition, the adhesive strength increase ratio of the surface (second adhesive surface) of the second pressure-sensitive adhesive layer may be less than 10, less than 5, or less than 2.

<Use>
The reinforcing film provided by this specification, for example, has a low adhesive strength for a while in a room temperature region (for example, 20 ° C. to 30 ° C.) after being bonded to an adherend, and good during this time Since reworkability can be exhibited, it can contribute to suppression of yield and high quality of a product including the reinforcing film. And the said reinforcement film can raise adhesion power largely by aging (it may be heating, aging, these combination etc.), and integrate a support base material and a to-be-adhered body firmly after that. Good reinforcement effect can be exhibited. For example, the reinforcing film can be firmly adhered to the adherend by heating at a desired timing, and the support base and the adherend can be firmly integrated. Moreover, the said reinforcement film is excellent in storage stability, for example, can exhibit desired performance stably, even if it preserve | saves in temperature range higher than room temperature. Taking advantage of such characteristics, the reinforcing film disclosed herein can be used to reinforce members included in various products in various fields.

  For example, in optical members used for optical products and electronic members used for electronic products, advanced integration, reduction in size and weight, thickness reduction are progressing, and a plurality of thin optical members having different linear expansion coefficients and thicknesses Electronic members may be stacked. Adhering the reinforcing film to such a member can impart appropriate rigidity to the optical member / electronic member. Thereby, in a manufacturing process and / or a product after manufacturing, it is possible to suppress curling and bending due to stress that may occur between a plurality of members having different coefficients of linear expansion and thickness.

  In addition, in the manufacturing process of optical products / electronic products, in a phase where a thin optical member / electronic member is subjected to shape processing such as cutting processing as described above, processing is performed by applying a reinforcing film to the member and processing. It is possible to relieve local stress concentration on the optical member / electronic member accompanying the problem and to reduce the risk of cracking, cracking, peeling of the laminated member, and the like. Attaching and handling the reinforcing member on the optical member / electronic member also alleviates local stress concentration during transport, lamination, rotation, etc. of the member, and also suppresses bending or bending of the member due to its own weight, etc. It can be useful.

  Furthermore, devices such as optical products and electronic products containing the above-mentioned reinforcing film collided with flying objects when placed under heavy objects when the devices were dropped at the stage used by consumers in the market In the case where unintentional stress is applied in some cases, the stress applied to the device can be alleviated by including the reinforcing film in the device. Thus, the inclusion of a reinforcing film in the device can improve the durability of the device.

  The reinforcing film disclosed herein can be preferably used, for example, in a mode of being attached to members constituting various portable devices (portable devices). Here, "portable" is not enough to be only portable, but means that an individual (a standard adult) has a portability that is relatively easy to carry. Do. In addition, examples of mobile devices here include mobile phones, smartphones, tablet computers, laptop computers, various wearable devices, digital cameras, digital video cameras, audio devices (portable music players, IC recorders, etc.), calculators (computers) Calculators, etc.), portable game devices, electronic dictionaries, electronic notebooks, electronic books, in-vehicle information devices, portable radios, portable TVs, portable printers, portable scanners, portable scanners, portable modems, etc. Clocks, flashlights, hand mirrors etc. may be included. Examples of members constituting the portable electronic device may include an optical film, a display panel and the like used in an image display device such as a thin layer display such as a liquid crystal display and a film type display. The reinforcing film disclosed herein can be preferably used also in a mode of being attached to various members in automobiles, home appliances, and the like.

The matters disclosed by this specification include the following.
(1) a supporting substrate having a first surface and a second surface;
A pressure-sensitive adhesive layer laminated on the first surface of the support base,
Including
The supporting substrate contains a resin film as a base film,
The second surface of the pressure-sensitive adhesive layer is fixed to the first surface of the support base,
The first surface of the pressure-sensitive adhesive layer is in contact with the peelable surface,
The water contact angle of the releasable surface is at least 100 degrees,
The pressure-sensitive adhesive layer contains a polymer A having a glass transition temperature (Tg) of less than 0 ° C., and a polymer B which is a copolymer of a monomer having a polyorganosiloxane skeleton and a (meth) acrylic monomer.
After bonding the first side of the pressure-sensitive adhesive layer to a stainless steel plate, the adhesive power N2 after heating at 80 ° C. for 5 minutes and then standing at 23 ° C. for 30 minutes corresponds to stainless steel on the first side of the pressure-sensitive adhesive layer Reinforcing film which is ten times or more of adhesive power N1 after leaving it to stand for 30 minutes at 23 ° C after pasting together to a steel plate.
(2) The reinforcing film according to (1), wherein the releasable surface is a surface of a release layer containing silicon (Si).
(3) The reinforcement film as described in said (2) whose atomic ratio of Si in the said peelable surface is 15 atomic% or more and 30 atomic% or less.
(4) The reinforcement film as described in said (1) whose said peelable surface is a surface of the peeling layer formed of the long chain alkyl type peeling process agent.
(5) The reinforcing film according to any one of the above (1) to (4), wherein the thickness of the support base is 30 μm or more.
(6) The reinforcing film according to any one of (1) to (5), wherein the thickness of the support base is 1.1 times or more and 10 times or less the thickness of the pressure-sensitive adhesive layer.
(7) The reinforcing film according to any one of (1) to (6), wherein the polymer B has a weight average molecular weight of 1,000 or more and 30,000 or less.
(8) The content of the polymer B in the pressure-sensitive adhesive layer is 0.05 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the polymer A according to any one of (1) to (7) Reinforcement film.
(9) The reinforcing film according to any one of the above (1) to (8), wherein the releasable surface is a surface of a release liner.
(10) The reinforcing film according to any one of the above (1) to (9), wherein the thickness of the release liner is 30 μm to 100 μm.
(11) The reinforcing film according to any one of the above (1) to (10), wherein the thickness of the pressure-sensitive adhesive layer is 3 μm to 100 μm (for example, 20 μm to 50 μm).
(12) The reinforcing film according to any one of (1) to (11), wherein the base film is a polyester film having a thickness of 35 μm or more (for example, a thickness of 35 μm or more and 500 μm or less).
(13) The reinforcing film according to (12), wherein the base film is a PET film having a thickness of 50 μm or more (for example, a thickness of 50 μm to 200 μm).
(14) The reinforcing film according to any one of (1) to (13) above, wherein the polymer A is an acrylic polymer.
(15) The reinforcement film as described in said (14) in which the said acryl-type polymer contains N-vinyl cyclic amide and a hydroxyl-containing monomer as a monomer unit. ,
(16) The reinforcing film according to any one of the above (1) to (15), wherein the pressure-sensitive adhesive layer contains an isocyanate-based crosslinking agent.
(17) The reinforcing film according to any one of the above (1) to (16), wherein the adhesive strength N2 is 15 N / 25 mm or more.
(18) After storing the first surface of the pressure-sensitive adhesive layer on a stainless steel plate after storage for 7 days under the conditions of 60 ° C., 90% RH, and heating at 80 ° C. for 5 minutes, it is 30 minutes at 23 ° C. The adhesive strength N2 after leaving is 10 times or more of the adhesive strength N1 after leaving it for 30 minutes at 23 ° C. after bonding the first surface of the adhesive layer to a stainless steel plate, the above (1) to The reinforcement film in any one of (17).
(19) A reinforcing film with a release liner, comprising the reinforcing film according to any one of the above (1) to (18), and a release liner having the release surface.
(20) A member with a reinforcing film, comprising: a member; and the reinforcing film according to any one of the above (1) to (18), wherein the adhesive surface is attached to the member.
(21) The member with a reinforcing film according to (20), wherein the member is an optical member or an electronic member.
(22) A device comprising the member with a reinforcing film according to (20) or (21) above.
(23) A method for producing the reinforcing film according to any one of (1) to (18) above,
Bringing the liquid pressure-sensitive adhesive composition into contact with the first surface of the supporting substrate;
Curing the pressure-sensitive adhesive composition on the first surface to form the pressure-sensitive adhesive layer in this order.

  The following examples illustrate some of the embodiments of the present invention, but are not intended to limit the present invention to those shown in the specific examples. In the following description, "parts" and "%" are on a weight basis unless otherwise noted.

(Preparation of Polymer A1)
In a four-necked flask equipped with a stirring blade, thermometer, nitrogen gas inlet and condenser, 60 parts of 2EHA, 15 parts of N-vinyl-2-pyrrolidone (NVP), 10 parts of methyl methacrylate (MMA), 2-hydroxyethyl Charge 15 parts of Acrylate (HEA) and 200 parts of ethyl acetate as a polymerization solvent, stir at 60 ° C under nitrogen atmosphere for 2 hours, then charge 0.2 parts of AIBN as a thermal polymerization initiator, 6 hours at 60 ° C The reaction was carried out to obtain a solution of polymer A1. Mw of this polymer A1 was 1.1 million.

(Preparation of Polymer B1)
100 parts of toluene, 40 parts of MMA, 20 parts of n-butyl methacrylate (BMA), 2-ethylhexyl methacrylate (2EHMA) 20 in a four-necked flask equipped with a stirring blade, thermometer, nitrogen gas inlet pipe, condenser and dropping funnel The polyorganosiloxane skeleton-containing methacrylate monomer (trade name: X-22-174 ASX, manufactured by Shin-Etsu Chemical Co., Ltd.) having a functional group equivalent of 900 g / mol, and a polyorganosiloxane having a functional group equivalent of 4600 g / mol 11.3 parts of a skeleton-containing methacrylate monomer (trade name: KF-2012, manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.51 part of methyl thioglycollate as a chain transfer agent were charged. After stirring at 70 ° C. under a nitrogen atmosphere for 1 hour, 0.2 parts of AIBN is added as a thermal polymerization initiator, and after reacting for 2 hours at 70 ° C., 0.1 parts by weight of AIBN as a thermal polymerization initiator After charging, it was allowed to react at 80 ° C. for 5 hours. Thus, a solution of polymer B1 was obtained. Mw of this polymer B1 was 22000.

In addition, the weight average molecular weight of each polymer mentioned above was measured on condition of the following using GPC apparatus (made by Tosoh Corp., HLC-8220GPC), and it calculated | required by polystyrene conversion.
Sample concentration: 0.2 wt% (tetrahydrofuran (THF) solution)
Sample injection volume: 10 μl
-Eluent: THF-Flow rate: 0.6 ml / min
・ Measurement temperature: 40 ° C
·column:
Sample column; TSKguardcolumn SuperHZ-H (one) + TSKgel SuperHZM-H (two)
Reference column; TSKgel SuperH-RC (one)
・ Detector: Differential refractometer (RI)

(Preparation of Pressure-Sensitive Adhesive Composition C1)
In the solution of the polymer A1, 2.5 parts of the polymer B1 per 100 parts of the polymer A1 contained in the solution, an isocyanate crosslinking agent (trade name: Takenate D110N, trimethylolpropane xylylene diisocyanate, manufactured by Mitsui Chemicals, Inc.) 2.5 parts were added and uniformly mixed to prepare a pressure-sensitive adhesive composition C1.

<Production of Reinforcement Film with Release Liner>
(Example 1)
The adhesive composition C1 is directly applied to the first surface of a 125 μm thick polyethylene terephthalate (PET) film (trade name “Lumirror” manufactured by Toray Industries, Inc .; hereinafter, also referred to as “support base A”) as a support base The adhesive layer was formed to a thickness of 25 μm by applying and drying by heating at 110 ° C. for 2 minutes. By bonding the release surface of the release liner R1 to the surface (adhesive surface) of the pressure-sensitive adhesive layer, a release liner-attached reinforcing film in which the adhesive surface is in contact with the release surface is obtained. As release liner R1, MRQ50T100 (a release liner having a release layer with a silicone-based release treatment agent on one side of a polyester film, 50 μm in thickness) manufactured by Mitsubishi Chemical Corporation was used.

(Examples 2 to 6)
Release films with a release liner according to Examples 2 to 6 were produced in the same manner as Example 1, except that release liners R2 to R6 were used instead of the release liner R1. The following were used as release liners R2 to R6.
Release liner R2
100 parts of silicone type release agent (Shin-Etsu Chemical Co., Ltd., KS-847H) and 3.3 parts of silicone curing catalyst (Shin-Etsu Chemical Co., Ltd., CAT-PL-50T), Toluene (manufactured by Idemitsu Petrochemicals), n-hexane It diluted to 0.3% with the mixed solvent of the weight ratio 1: 2: 1 which consists of Maruzen Petrochemical) and methyl ethyl ketone (made by Idemitsu Kosan), and prepared the silicone type exfoliation treating agent. This release treatment agent was applied to one side of a 50 μm-thick PET film (Mitsubishi resin, Diafoil T100C50) and dried at 130 ° C. for 1 minute to prepare a release liner R2.
Release liner R3
92 parts of vinyl group-containing silicone release agent (Shin-Etsu Chemical Co., Ltd., KS-3703), 8 parts of release control agent (Shin-Etsu Chemical Co., Ltd., KS-3800) and platinum catalyst (Shin-Etsu Chemical Co., Ltd., CAT-PL-50T) Three parts were mixed with 680 parts of toluene as a dilution solvent and 680 parts of n-hexane to prepare a silicone-based release treatment agent. This release treatment agent was applied to one side of a 50 μm thick PET film (Mitsubishi resin, Diafoil T100C50) and dried at 130 ° C. for 1 minute to prepare a release liner R3.
Release liner R4
Vinyl group-containing silicone release agent (Shin-Etsu Chemical KS-3703) 80 parts, release control agent (Shin-Etsu Chemical KS-3800) 20 parts and platinum catalyst (Shin-Etsu Chemical CAT-PL-50T) Three parts were mixed with 680 parts of toluene as a dilution solvent and 680 parts of n-hexane to prepare a silicone-based release treatment agent. This release treatment agent was applied to one side of a 50 μm-thick PET film (Mitsubishi resin, Diafoil T100C50) and dried at 130 ° C. for 1 minute to prepare a release liner R4.
Release liner R5
In a reaction vessel equipped with a condenser, 200 parts of xylene (manufactured by Taiyo Kagaku Co., Ltd., xylol) and 600 parts of octadecyl isocyanate (manufactured by Ohara Palladium Chemical Co., Ltd., R-NCO) were charged, and heated while stirring. When xylene began to reflux, 100 parts of polyvinyl alcohol (Kuraray, KURARAY POVAL 205) was added little by little at intervals of 10 minutes for 2 hours. After the addition of polyvinyl alcohol, the reaction was further refluxed for 2 hours to complete the reaction. The reaction mixture was cooled to about 80 ° C. and then added to methanol, and the reaction product precipitated as a white precipitate. The precipitate is separated by filtration, 140 parts of xylene is added, heated and completely dissolved, and then the operation of adding and precipitating methanol again is repeated several times, and then the precipitate is washed with methanol and dried and pulverized. The resulting powder was diluted with water to 0.3% to prepare a long chain alkyl type release treating agent. This release treatment agent was applied to one side of a 50 μm-thick PET film (Mitsubishi resin, Diafoil T100C50) and dried at 130 ° C. for 1 minute to prepare a release liner R5.
Release liner R6
In a reaction vessel equipped with a condenser, 100 parts of acrylonitrile (manufactured by Showa Denko KK), 62.5 parts of stearyl methacrylate (SMA manufactured by Mitsubishi Gas Chemical Co., Ltd.), methacrylic acid (manufactured by Mitsubishi Rayon Co., Ltd.) 18 parts, 1.8 parts of 1-dodecanethiol (manufactured by Wako Pure Chemical Industries, Ltd., 1-dodecanethiol), 0.55 parts of benzoyl peroxide (manufactured by NOF Corporation, NAIPER BW), and The mixture was diluted to 24% with Petrochemicals), and reacted at 70 ° C. for 7 hours under a nitrogen stream. The obtained solution was diluted to 0.3% with toluene to prepare a long chain alkyl type release treating agent. This release treatment agent was applied to one side of a 50 μm thick PET film (Mitsubishi resin, Diafoil T100C50), and dried at 130 ° C. for 1 minute to prepare a release liner R6.

  The water contact angles of the release liners R1 to R6 were measured by the above-mentioned method. The results are shown in Table 1.

Moreover, about the peeling surface (surface of a peeling layer) of said peeling liner R1-R6, the measurement by X ray photoelectron spectroscopy (ESCA) was performed on condition of the following, and the elemental ratio of Si was measured. The results are shown in Table 1.
Device: ULVAC PHI PHI Quantera SXM
X-ray source: monochrome AlKα
XRay Setting: 100 μmφ [15 kV, 25 W]
Photoelectron extraction angle: 45 ° to the sample surface

(Storage condition)
The release film with a release liner according to each example was allowed to stand in an environment of 23 ° C. and 50% RH for 4 days to obtain a sample in the initial state (before storage) of the release film with a release liner.
The above-described release film with a release liner in the initial state was further stored under conditions of 60 ° C. and 90% RH for 7 days as a sample after storage under Condition 1.
What preserve | saved the reinforcement film with a release liner of the said initial state for 7 days on the conditions of 85 degreeC further was made into the sample after the preservation | save by condition 2. FIG.
The following evaluation tests were carried out for each of the samples after storage under Condition 2 before storage and after storage under Condition 1. In addition, the sample after preservation | save by conditions 1 and 2 was used for each evaluation test, after returning to the environment of 23 degreeC and 50% RH from the environment which concerns on each condition, and leaving still for 30 minutes.

<Measurement of liner peeling force>
What peeled the reinforcement film with a release liner which concerns on each case into 25 mm width with a release liner was made into the test piece. The above-mentioned test piece is set in a universal tensile and compression tester (apparatus name: “tensile compression tester, TCM-1 kNB” manufactured by Minebea Co., Ltd.) under an environment of 23 ° C. and 50% RH, and the peeling angle is 180 degrees, the tensile speed is 300 mm. The release liner was peeled off from the adhesive surface under the conditions of 1 / min, and the 180 ° peel adhesion at this time (resistance to the above-mentioned tension) was measured. The measurement was performed three times, and their average value is shown in Table 1 as a liner peeling force (N0) [N / 25 mm].

<Measurement of adhesion to SUS>
The reinforcement film according to each example was cut into 25 mm width together with the release liner as a test piece, and the toluene-cleaned SUS plate (SUS 304 BA plate) was used as an adherend in the following procedures for initial tack N 1 and adhesion after heating The force N2 was measured.
(Measurement of initial adhesion)
Under a standard environment of 23 ° C. and 50% RH, the release liner covering the adhesive surface of each test piece was peeled off, and the exposed adhesive surface was crimped to the adherend by one reciprocation of a 2 kg roller. After leaving the test pieces pressure-bonded to the adherend in this way for 30 minutes under the above standard environment, using a universal tensile compression tester (apparatus name "tensile compression tester, TCM-1kNB" manufactured by Minebea Co., Ltd.) In accordance with JIS Z 0237, the 180 ° peel strength (resistance to the above-mentioned tension) was measured at a peeling angle of 180 ° and a tensile speed of 300 mm / min. The measurement was performed three times, and their average value was shown in Table 1 as initial tack (N1) [N / 25 mm].
(Measurement of adhesion after heating)
The test piece pressed onto the adherend in the same manner as in the measurement of initial adhesion was heated at 80 ° C. for 5 minutes and then left under the above standard environment for 30 minutes, and then the 180 ° peel adhesion was similarly measured. . The measurement was carried out three times, and their average value is shown in Table 1 as adhesion after heating (N2) [N / 25 mm]. In addition, it was confirmed that the reinforcement film according to Examples 1 to 6 does not cause anchorage breakage at the time of measurement of the adhesion after heating in any of the samples after storage under the condition 2 before storage and after the storage under the condition 1 .

  As shown in Table 1, the reinforcing films of Examples 1 to 5 prepared in the form of a reinforcing film with a release liner in which the adhesive surface was in contact with the peeling surface having a water contact angle of 100 degrees or more Also, the initial low tackiness and the strong tackiness at the time of use were exhibited well as or before the storage. According to the reinforcing films of Examples 1 to 4 in which the release surface is a release surface with a silicone release treatment agent, better results were obtained. That is, it was confirmed that, even after storage under the more severe condition 2, the reinforcing films of Examples 1 to 4 exhibited well the initial low adhesiveness and the strong adhesiveness at the time of use. Further, all of the reinforcing films of Examples 1 to 5 were able to be easily peeled off from the peeling surface after storage under the conditions 1 and 2. The reinforcing films of Examples 1 to 4 had a particularly small difference in liner peel strength between after storage and before storage under Conditions 1 and 2 and were excellent in the stability of the liner peel strength.

  On the other hand, the reinforcing film of Example 6 prepared in the form of a reinforcing film with a release liner in which the adhesive surface is in contact with the peeling surface having a water contact angle of less than 100 degrees The initial tack was clearly higher. Further, in the reinforcing film of Example 6, the liner peeling force was greatly increased by the storage under the condition 1. After storage under Condition 2, the liner peel strength increased further, and the ease of removal of the release liner decreased.

(Examples 7-8)
In Examples 1 and 6, a polyimide resin film (a thickness of 50 μm, trade name “Neoprim S-100”; hereinafter, also referred to as a supporting substrate B) manufactured by Mitsubishi Gas Chemical Co., Ltd. was used in place of the supporting substrate A. The release film with a release liner according to Examples 7 and 8 was obtained in the same manner as in Examples 1 and 6 with respect to the other points.

  The same evaluation as in Examples 1 to 6 was carried out on the reinforcing film with release liner according to Examples 7 and 8. The results are shown in Table 2.

  As shown in Table 2, Example 7 using release liner R1 has low liner peel strength even after storage under conditions 1 and 2, and exhibits good initial low tackiness and strong tackiness at the time of use It was On the other hand, in Example 8 using the release liner R6, the initial adhesion and the liner peeling force tended to increase due to storage. Thus, also in the configuration using the supporting substrate B, the same tendency as the configuration using the supporting substrate A was observed.

(Examples 9 to 12)
In Examples 7 and 8, a polyimide resin film (a thickness of 50 μm, trade name “Kapton 200H”; hereinafter, also referred to as a supporting substrate C) manufactured by Kaneka Corporation was used instead of the supporting substrate B. The release film with a release liner according to Examples 9 and 10 was obtained in the same manner as in Examples 7 and 8 with respect to the other points.

(Examples 11 to 12)
In Examples 7 and 8, a polyimide resin film (a thickness of 50 μm, trade name “UPILEX 50S”; hereinafter, also referred to as a supporting substrate D) manufactured by Ube Industries, Ltd. was used in place of the supporting substrate B. The release film with a release liner according to Examples 11 and 12 was obtained in the same manner as in Examples 7 and 8 with respect to the other points.

  About the reinforcement film with a release liner which concerns on Examples 9-12, it carried out similarly to Examples 1-6, and evaluated the change of the peeling performance by preservation | save. The results are shown in Table 3.

  As shown in Table 3, in the configuration using the supporting substrates C and D, the same tendency as the configuration using the supporting substrate B was observed. That is, Examples 9 and 11 which used release liner R1 were excellent in stability of liner release force compared with Examples 10 and 12 which used release liner R6.

  As mentioned above, although the specific example of this invention was described in detail, these are only an illustration and do not limit a claim. The art set forth in the claims includes various variations and modifications of the specific examples illustrated above.

1, 2 Reinforcement film 10 Support substrate 10A First surface 10B Second surface 21 Pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer)
21A first surface (adhesive surface, first adhesive surface)
21B second side (rear side)
22 Pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer)
22A adhesive side (second adhesive side)
31, 32 Release liner 31A, 32A Release surface (release surface)
Reinforcement film with 100, 200 release liner

Claims (8)

A support substrate having a first side and a second side;
A pressure-sensitive adhesive layer laminated on the first surface of the support base,
Including
The supporting substrate contains a resin film as a base film,
The second surface of the pressure-sensitive adhesive layer is fixed to the first surface of the support base,
The first surface of the pressure-sensitive adhesive layer is in contact with the peelable surface,
The water contact angle of the peelable surface is at least 100 degrees,
The pressure-sensitive adhesive layer contains a polymer A having a glass transition temperature of less than 0 ° C., and a polymer B which is a copolymer of a monomer having a polyorganosiloxane skeleton and a (meth) acrylic monomer.
After bonding the first surface of the pressure-sensitive adhesive layer to a stainless steel plate, the adhesive power N2 after heating at 80 ° C. for 5 minutes and then standing at 23 ° C. for 30 minutes corresponds to stainless steel on the first surface of the pressure-sensitive adhesive layer Reinforcing film which is ten times or more of adhesive power N1 after leaving it to stand for 30 minutes at 23 ° C after pasting together to a steel plate.   The reinforcing film according to claim 1, wherein the peelable surface is a surface of a release layer containing silicon (Si).   The reinforcing film according to claim 1, wherein the release surface is a surface of a release layer formed by a long chain alkyl release treatment agent.   The reinforcing film according to any one of claims 1 to 3, wherein the thickness of the support substrate is 30 μm or more.   The reinforcing film according to any one of claims 1 to 4, wherein the thickness of the support substrate is 1.1 times or more and 10 times or less the thickness of the pressure-sensitive adhesive layer.   The reinforcing film according to any one of claims 1 to 5, wherein the polymer B has a weight average molecular weight of 10000 or more and 50000 or less.   The reinforcing film according to any one of claims 1 to 6, wherein a content of the polymer B in the pressure-sensitive adhesive layer is 0.05 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the polymer A.   The reinforcing film according to any one of claims 1 to 7, wherein the releasable surface is a surface of a release liner.

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