JP2014047310A - Adhesive film and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive film which exhibits a stable adhesive force in a heated state over time, which is unaccompanied by the entrapment of bubbles at the time of the pasting thereof, and which does not slide or peel autonomously following the pasting thereof but can be easily released.SOLUTION: The provided adhesive film is an adhesive film comprising a substrate film and an adhesive layer formed on at least one surface of the substrate film; the adhesive layer is provided by coating, on the substrate film, a silicone adhesive composition having an initial adhesive force of 0.2-40 N/m as measured based on the 180° exfoliation test in compliance with JIS Z 0237 and, after having been pasted and stored at 100°C for 48 hours, a residual adhesive force is commensurate with no more than 300% of the initial adhesive force.

Description

  The present invention relates to an adhesive film using a silicone adhesive composition and a method for producing the same.

  Adhesive films are used for transporting fine parts, optical materials, and the like in the process, for protection to prevent scratches, or for masking parts that do not require processing. The adhesive film needs to have characteristics such as no bubble entrapment and good bubble repellency when applied. It is necessary that the attached adhesive film does not slip or peel off by itself, but it is necessary that it is easily peeled off (removed) at the time of replacement.

  Conventionally, organic resin adhesives such as acrylic adhesives and urethane adhesives have been used as adhesives for this adhesive film, but adhesive films using such adhesives are Was involved. When bubbles are involved, the inspection of fine parts may fail due to the bubbles, and operations such as re-sticking and extruding bubbles are required. In order to extrude the entrained bubbles, the components themselves may be damaged while repeatedly extruding the bubbles from the surface of the adhesive film with a finger or re-applying them.

  In recent years, particularly in electronic devices such as mobile phones and mobile tablets equipped with touch panel devices, the weight has been reduced in order to improve portability. Glass parts and the like used for touch panels and the like used in these electronic devices are also thin and easily broken for weight reduction, and handling is becoming difficult.

  When sticking the adhesive film for the purpose of protection to these easily-damaged adherends and small adherends, they are left in the state of being stuck to the adherends, sometimes for a long time, Used for storage and transportation. At this time, for example, it may be left under high temperature and high humidity of 30 to 60 ° C. and 65 to 95% RH. For this reason, even when it is placed in a wet heat environment in a state of being attached to a release liner or an adherend, the adhesive strength should not be greatly increased when the adhesive film is peeled off.

  Organopolysiloxane compositions and the like are known as pressure-sensitive adhesive compositions for pressure-sensitive adhesive films for displays (Patent Documents 1 to 4). However, these are described for stability in general storage conditions (25 to 60 ° C., 50 to 95% RH). For example, re-peeling after heating at 60 to 100 ° C. as an adhesive film for process protection Is not mentioned.

JP 2004-225005 A JP 2006-152266 A JP 2007-191537 A JP 2011-102336 A

  As an adhesive film that protects the surface during process transportation, an adhesive film for protection during the heating process, and an adhesive film for transportation, adhesion after treatment with respect to initial adhesive force when parts processing is performed at 60 to 100 ° C When the force increase is large, there is a problem that a part is damaged after the treatment is completed, or a so-called adhesive residue is generated in which the adhesive remains on the adherend surface.

  The present invention has been made in view of the above-mentioned problems. The adhesive force is stable over time, there is no bubble entrainment at the time of application, and it does not slip or peel off after application, but it is easy to peel off. An object is to provide an adhesive film.

  The present invention has been made to solve the above-mentioned problems, and is an adhesive film comprising a base film and an adhesive layer formed on at least one surface of the base film, the adhesive layer However, the initial adhesive strength measured by a 180 ° peeling test method according to JIS Z 0237 is 0.2 to 40 N / m, and the adhesive strength after storing for 48 hours at 100 ° C. is 300% or less of the initial adhesive strength. A pressure-sensitive adhesive film is provided by coating the base film with the silicone pressure-sensitive adhesive composition.

  In this case, the silicone adhesive composition having an initial adhesive strength of 0.4 to 20 N / m and an adhesive strength after being bonded and stored at 80 ° C. for 48 hours is 200% or less of the initial adhesive strength. It is preferable that it is an adhesive film formed by coating a material film.

  If this is the case, there will be no bubble entrapment at the time of sticking, and it will not slip or peel off after sticking, but it will have a stable adhesive force over time and will be easier to peel off. It can be.

  In these cases, the thickness of the pressure-sensitive adhesive layer is preferably 2 to 200 μm.

  As described above, if the thickness of the pressure-sensitive adhesive layer is 2 μm or more, sufficient pressure-sensitive adhesive force can be obtained, and if it is 200 μm or less, there is no fear that the pressure-sensitive adhesive force becomes excessive, and it is economically advantageous. It can be.

The silicone pressure-sensitive adhesive composition is
(A) Among all organic groups having two or more alkenyl groups in one molecule and bonded to a silicon atom, the phenyl group is contained in an amount of 0 to 12 mol%, and the alkenyl group is contained in an amount of 0.15 to 7.5 mol. %, And a diorganopolysiloxane having a viscosity at 25 ° C. of 100,000 mPa · s or more: 90 to 40 parts by mass,
(B) Organopolysiloxane containing R ¹ ₃ SiO _0.5 unit and SiO ₂ unit and having a R ¹ ₃ SiO _0.5 unit / SiO ₂ unit molar ratio of 0.6 to 1.7 (R ¹ Is a monovalent hydrocarbon group having 1 to 10 carbon atoms.): 10 to 60 parts by mass,
(C) Organohydrogenpolysiloxane containing 3 or more SiH groups in one molecule: (A), an amount such that the molar ratio of SiH groups to alkenyl groups in component (B) is 0.5 to 10,
(D) Control agent: 0 to 8.0 parts by mass with respect to 100 parts by mass in total of the components (A) and (B),
(E) Addition reaction catalyst: 5 to 2,000 ppm as a noble metal component with respect to a total of 100 parts by mass of component (A) and component (B),
(F) Organic solvent: It is preferable that it is a silicone adhesive composition containing 25-900 mass parts with respect to 100 mass parts in total of (A) component and (B) component.

  With such a silicone pressure-sensitive adhesive composition, there is no air bubble entrainment at the time of application, and it does not slip or peel off after application, but the adhesive force is stable and peels over time. It can be set as the adhesive film which is easy.

  Furthermore, the phenyl group content of the component (A) is 1 to 9 mol%, and a pressure-sensitive adhesive film having no primer layer between the base film and the pressure-sensitive adhesive layer can be obtained.

  If it is such (A) component, it can be set as the adhesive film which does not have a primer layer between the said base film and the said adhesive layer.

  The present invention also relates to a method for producing an adhesive film, wherein the initial adhesive force measured by a 180 ° peeling test method in accordance with JIS Z 0237 is 0.2 to 40 N / m and bonded and stored at 100 ° C. for 48 hours. A step of applying a silicone adhesive composition having an adhesive strength of 300% or less of the initial adhesive strength on at least one surface of the base film to form an adhesive layer. A method for producing a film is provided.

  In this case, the silicone adhesive composition has an initial adhesive strength of 0.4 to 20 N / m, and an adhesive strength after bonding and storage at 80 ° C. for 48 hours is 200% or less of the initial adhesive strength. It is preferable to use an adhesive composition.

  With such a method for producing an adhesive film, there is no air bubble entrainment at the time of application, and it does not slip or peel off after application, but the adhesive force is stable over time, and easier to peel off. A pressure-sensitive adhesive film can be produced.

  As described above, if the adhesive film according to the present invention is used, there is no entrainment of bubbles at the time of application, and it does not slip or peel off after application, but the adhesive force is stable and peels over time. It can be set as the adhesive film which is easy to do.

  As described above, conventional adhesive films have entrained bubbles at the time of application, and re-peelability with heating is not good. As a result of intensive studies to solve these problems, the present inventors have found that the removability has a correlation with the rate of increase in adhesive strength over time, and can be an adhesive film having a predetermined adhesive force change rate. For example, the present invention has been completed by finding that there is no air bubble entrainment at the time of pasting, and it does not slip or peel by itself after pasting, but the adhesive strength is stable over time and can be easily peeled off. I let you.

  Hereinafter, although the adhesive film of this invention and its manufacturing method are demonstrated in detail, this invention is not limited to these.

  The present invention is a pressure-sensitive adhesive film comprising a base film and a pressure-sensitive adhesive layer formed on at least one side of the base film, wherein the pressure-sensitive adhesive layer is a 180 ° peeling test method according to JIS Z 0237 A silicone pressure-sensitive adhesive composition having an initial adhesive force measured by 0.2 to 40 N / m and a bonded adhesive strength of 100% or less after storage for 48 hours at 100 ° C. is applied to the base film. It is an adhesive film that is formed by coating.

  Although the thickness of the said adhesive film is not specifically limited, For example, the adhesive film coated on the base film of thickness 23 micrometers can be used so that the thickness of an adhesive layer may be 30 micrometers. The initial adhesive strength of the silicone pressure-sensitive adhesive composition is 0.2 to 40 N / m, preferably 0.4 to 20 N / m. If it is less than 0.2 N / m, the adhesive force is insufficient and it will not stick to fixing and transporting parts. If it exceeds 40 N / m, the adhesive will be excessively peeled and the parts will be damaged. Is difficult to peel from the part.

  Further, when the bonded state is applied for a long period or when heat treatment is performed, an increase in adhesive strength is confirmed. When using a pressure-sensitive adhesive film coated on polyethylene terephthalate which is a base film having a thickness of 23 μm so that the thickness of the pressure-sensitive adhesive layer is 30 μm, the 180 ° peeling adhesive force measurement method shown in JIS Z 0237 is used. When the adhesive strength to the stainless steel plate is measured, the adhesive strength when bonded at 100 ° C. for 48 hours is 300% or less of the initial adhesive strength, preferably 200% or less, more preferably 120% or less. If it exceeds 300% of the initial adhesive strength, the adhesive strength is excessive and the component is damaged when it is peeled off, making it difficult to peel the adhesive film from the component.

  In this case, in particular, the initial adhesive strength is 0.4 to 20 N / m, and it is more preferable that the adhesive strength after being bonded and stored at 80 ° C. for 48 hours is 200% or less of the initial adhesive strength, 120% is more preferable.

  With such an adhesive film, it is easier to peel the adhesive film from the part.

  Moreover, it is preferable that the thickness of the said adhesive layer is 2-200 micrometers, More preferably, it is 3-100 micrometers, More preferably, it is 30-100 micrometers.

  If it is 2 μm or more, sufficient adhesive force can be obtained, and if it is 200 μm or less, there is no fear that the adhesive force will be excessive, and at the same time there is no possibility that it will be disadvantageous economically.

  Base film includes polyester, poly (meth) acrylate, polycarbonate, polyethylene, polypropylene, polystyrene, polyamide, polyimide, polyphenylene sulfide, polytetrafluoroethylene, polyvinyl chloride, polyurethane, triacetyl cellulose, polyacetal, norbornene resin ( "Arton" (registered trademark), manufactured by JSR), cycloolefin resin (manufactured by Nippon Zeon Co., Ltd., "ZEONOR" (registered trademark)), plastic film substrate made of epoxy resin, phenol resin, etc. A composite base material formed by laminating a plurality of them is exemplified. Among these, polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyimide films, polyacrylate films such as polyacrylate and polymethacrylate, and polycarbonate films are preferable.

  Although the thickness of a base film is not limited, Preferably it is 2-300 micrometers, More preferably, it is 10-150 micrometers.

Examples of the silicone pressure-sensitive adhesive composition include:
(A) Among all organic groups having two or more alkenyl groups in one molecule and bonded to a silicon atom, the phenyl group is contained in an amount of 0 to 12 mol%, and the alkenyl group is contained in an amount of 0.15 to 7.5 mol. %, And a diorganopolysiloxane having a viscosity at 25 ° C. of 100,000 mPa · s or more: 90 to 40 parts by mass,
(B) Organopolysiloxane containing R ¹ ₃ SiO _0.5 unit and SiO ₂ unit and having a R ¹ ₃ SiO _0.5 unit / SiO ₂ unit molar ratio of 0.6 to 1.7 (R ¹ Is a monovalent hydrocarbon group having 1 to 10 carbon atoms.): 10 to 60 parts by mass,
(C) Organohydrogenpolysiloxane containing 3 or more SiH groups in one molecule: (A), an amount such that the molar ratio of SiH groups to alkenyl groups in component (B) is 0.5 to 10,
(D) Control agent: 0 to 8.0 parts by mass with respect to 100 parts by mass in total of the components (A) and (B),
(E) Addition reaction catalyst: 5 to 2,000 ppm as a noble metal component with respect to a total of 100 parts by mass of component (A) and component (B),
(F) Organic solvent: The silicone adhesive composition containing 25-900 mass parts with respect to a total of 100 mass parts of (A) component and (B) component is mentioned preferably.

  If such a silicone pressure-sensitive adhesive composition has the above-mentioned characteristics, there is no bubble entrainment at the time of application, and it does not shift or peel off alone after application, but the adhesive force is stable over time, It can be set as the adhesive film which is easy to peel.

  Hereinafter, the components (A) to (F) of the silicone pressure-sensitive adhesive composition will be described in detail.

<(A) component>
Component (A) is a diorganopolysiloxane that contains at least two alkenyl groups in one molecule and may or may not contain a phenyl group.

(A) As a component, what is shown by a following formula can be illustrated, for example.
R ³ _a R ² _(3-a) SiO (R ³ R ² SiO) _m (R ² ₂ SiO) _n
-SiR ² _(3-a) R ³ _a (1)
HOR ² ₂ SiO (R ³ R ² SiO) _{m + 2} (R ² ₂ SiO) _n SiR ² ₂ OH (2)
(R ³ _a R ² _(3-a) SiO _1/2 ) _o (R ³ R ² SiO _2/2 ) _p
-(R ² ₂ SiO _2/2 ) _q (R ⁴ SiO _3/2 ) _r (SiO _4/2 ) _s (3)
(In the formula, R ² is a substituted or unsubstituted monovalent hydrocarbon group having no identical or different aliphatic unsaturated bond, R ³ is an alkenyl group-containing organic group, a is an integer of 0 to 3, Preferably, m is 0 or more, n is an integer of 10 or more, m is 2 or more when a is 0, and m + n is the viscosity of this diorganopolysiloxane at 25 ° C. of 100,000 mPa -A number greater than or equal to s, R ⁴ is R ² or R ³ , o is an integer of 3 to 12, p is 0 or more, q is an integer of 10 or more, r + s is an integer of 1 to 5, and o + p + q + r + s is (This is a number that makes this diorganopolysiloxane have a viscosity at 25 ° C. of 100,000 mPa · s or more.)

Here, R ² is preferably one having 1 to 10 carbon atoms, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, a cycloalkyl group such as a cyclohexyl group, a phenyl group or a tolyl group. A 3-aminopropyl group in which part or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with other groups such as halogen, amino group, hydroxyl group, cyano group, Examples include 3,3,3-trifluoropropyl group, 3-hydroxypropyl group, 3-cyanopropyl group and the like. R ² is particularly preferably a methyl group or a phenyl group.

R ³ is preferably one having 2 to 10 carbon atoms, for example, vinyl group, allyl group, hexenyl group, octenyl group, acryloylpropyl group, acryloylmethyl group, methacryloylpropyl group, cyclohexenylethyl group, vinyloxy. A propyl group is preferred, and a vinyl group is particularly preferred industrially.

  The alkenyl group content in component (A) is preferably 0.15 to 7.5 mol% of the total organic groups of this diorganopolysiloxane. As an adhesive film, suitable tackiness can be achieved even at the initial stage and after heating at 100 ° C. for 48 hours. Furthermore, what is 0.15-1.5 mol% is preferable. If it is 0.15 mol% or more, the curability of the pressure-sensitive adhesive composition will be sufficient, and if it is 7.5 mol% or less, the adhesiveness will not be lowered and sufficient adhesive force can be obtained.

The content of the phenyl group in the component (A) is preferably 0 to 12 mol%, more preferably 1 to 9 mol%, of all the organic groups of the diorganopolysiloxane. When the phenyl group content is 12 mol% or less, there are few cyclic low-molecular siloxane residues, and there is no fear that an adhesive residue will remain during re-peeling. The phenyl group is a (C ₆ H ₅ ) ₂ SiO _2/2 unit, a (C ₆ H ₅ ) R ⁰ SiO _2/2 unit (R ⁰ is a substituted or unsubstituted phenyl group having no aliphatic unsaturated bond) Or a (C ₆ H ₅ ) SiO _3/2 unit, and a (C ₆ H ₅ ) ₂ SiO _2/2 unit. Preferably there is.

  When the phenyl group of the component (A) is 0 mol%, the adhesion to the film substrate is lowered, and in particular, the adhesion to the substrate when the adhesive film is left with heating or moist heat. May decrease, making re-peeling difficult. In this case, if a primer or the like is used as necessary, the close contact with the substrate is improved and the removability is improved.

  If the phenyl group content of the component (A) is 1 to 9 mol%, it can be an adhesive film that does not have such a primer layer between the base film and the adhesive layer. More preferable in terms of cost.

  The diorganopolysiloxane may be in the form of oil or raw rubber. The viscosity of the component (A) is preferably 100,000 mPa · s or more if it is oily at 25 ° C. If it is 100,000 mPa · s or more, there is no fear that the coatability is lowered and the coated surface is repelled.

  Moreover, if it is a raw rubber-like thing whose viscosity exceeds 1,000,000 mPa · s, the viscosity (30% dissolution viscosity) when dissolved in toluene so as to have a concentration of 30% by mass is 100,000 mPa · s. It is preferable that it is s or less. Furthermore, it is preferable that 30% melt viscosity is 3,000-30,000 mPa * s. If the 30% solution viscosity is 100,000 mPa · s or less, the silicone pressure-sensitive adhesive composition does not become too viscous, and there is no possibility that stirring during production becomes difficult.

  Furthermore, (A) component may use 2 or more types together. In this case, the total of alkenyl groups contained in the component (A) is preferably 0.15 to 7.5 mol%. In the present invention, the viscosity is a value at 25 ° C. measured by a rotational viscometer.

  The component (A) is usually produced by ring-opening polymerization of a monomer such as octamethylcyclotetrasiloxane using a catalyst. After polymerization, the cyclic low molecular weight siloxane is contained. It is preferable to use a molecular siloxane which is distilled off while heating and reducing pressure while allowing an inert gas to pass through the reaction product.

<(B) component>
Component (B) is an organopolysiloxane containing _0.5 units of R ¹ ₃ SiO _0.5 and SiO ₂ units and having a molar ratio of R ¹ ₃ SiO _0.5 units / SiO ₂ units of 0.6 to 1.7. Is preferred. If the molar ratio of R ¹ ₃ SiO _0.5 unit / SiO ₂ unit is 0.6 or more, there is no risk of lowering the adhesive strength or tack, and if it is 1.7 or lower, the adhesive strength or holding power may be decreased. This is preferable because there is not.

Here, R ¹ is a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, specifically an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group, a cycloalkyl group, a phenyl group And an alkenyl group such as a vinyl group, an allyl group, and a hexenyl group. Furthermore, some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with other groups such as halogen, amino group, hydroxyl group, cyano group, 3-aminopropyl group, 3,3,3-trimethyl group. Examples thereof include a fluoropropyl group, a 3-hydroxypropyl group, and a 3-cyanopropyl group. Among these, a methyl group is preferable.

  The component (B) may have an OH group, and the OH group content is preferably 0.01 to 4.0% by mass of the total mass of the component (B). If the OH group is 0.01% by mass or more, the cohesive force of the pressure-sensitive adhesive is not lowered, and if it is 4.0% by mass or less, the tack of the pressure-sensitive adhesive is not lowered, which is preferable.

(B) 2 or more types of components may be used together. It is also possible to contain R ¹ SiO _1.5 units and R ¹ ₂ SiO units in the component (B).

In the silicone pressure-sensitive adhesive composition, it is effective that the ratio of the diorganopolysiloxane containing an alkenyl group to the organopolysiloxane containing R ¹ ₃ SiO _0.5 unit and SiO ₂ is within a certain range. That is, the mass ratio of the components (A) and (B) is preferably (A) / (B) = 90/10 to 40/60. In particular, 90/10 to 60/40 is preferable. If the blending ratio of the diorganopolysiloxane of component (A) is 90/10 or less, there is no fear that the releasability will be lowered due to too strong adhesive strength with respect to the initial adhesive strength, and 40/60 or more. If it exists, there is no fear that the initial adhesive force cannot be obtained and the bonding becomes difficult, which is preferable.

<(C) component>
Component (C) is a crosslinking agent and is an organohydrogenpolysiloxane having three or more SiH groups (hydrogen atoms bonded to silicon atoms) in one molecule. Linear or branched ones can be used.

(C) As a component, what is shown by a following formula can be illustrated, However, It is not limited to these.
H _b R ² _(3-b) SiO (HR ² SiO) _t (R ² ₂ SiO) _{u
^{-SiR 2 (3-b) H}} b
And (H _b R ² _(3-b) SiO _1/2 ) _v (HR ² SiO _2/2 ) _w
-(R ² ₂ SiO _2/2 ) _x (R ² SiO _3/2 ) _y (SiO _4/2 ) _z
(In the above formula, R ² is a substituted or unsubstituted monovalent hydrocarbon group having no identical or different aliphatic unsaturated bond, b is 0 or 1, t and u are integers of 0 or more. When b is 0, t is at least 2. t + u is a number at which the viscosity of this organohydrogenpolysiloxane at 25 ° C. is 1 to 1000 mPa · s, and v is an integer of 3 to 12 , W is 0 or more, y + z is an integer of 1 to 5, and v + w + x + y + z is a number that makes the viscosity of this diorganopolysiloxane at 25 ° C. 1 to 500 mPa · s.)

Here, R ² is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms as described above, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, or a butyl group, or a cyclohexyl group. And aryl groups such as a phenyl group and a tolyl group. Furthermore, some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with other groups such as halogen, amino group, hydroxyl group, cyano group, 3-aminopropyl group, 3,3,3-trimethyl. Examples also include a fluoropropyl group, a 3-hydroxypropyl group, and a 3-cyanopropyl group. In particular, a methyl group and a phenyl group are preferable.

The viscosity of the organohydrogenpolysiloxane (C) at 25 ° C. is preferably 1 to 1,000 mPa · s, and more preferably 2 to 500 mPa · s. Also, a mixture of two or more kinds may be used. ^{_{Furthermore, [R 2 SiO 3/2],}} [HSiO 3/2], can also be exemplified a structure containing _{[SiO 4/2].}

  The amount of component (C) used is preferably such that the molar ratio of SiH groups in component (C) to alkenyl groups in components (A) and (B) is 0.5-10, and 0.8-7. More preferably, it is blended so as to be in the range of .5. If it is 0.5 or more, there is no fear of a decrease in cohesive force and holding force due to a low crosslinking density, and if it is 10 or less, an appropriate adhesive force and tack due to a high crosslinking density. There is no fear of getting lost.

<(D) component>
Component (D) is a control agent, and is added to prevent the treatment liquid from thickening or gelling before heat-curing when the silicone adhesive composition is prepared or applied to the substrate. It is. Specific examples include 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 1-ethynylcyclohexanol, 3 -Methyl-3-trimethylsiloxy-1-butyne, 3-methyl-3-trimethylsiloxy-1-pentyne, 3,5-dimethyl-3-trimethylsiloxy-1-hexyne, 1-ethynyl-1-trimethylsiloxycyclohexane, Bis (2,2-dimethyl-3-butynoxy) dimethylsilane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, 1,1,3,3-tetramethyl -1,3-divinyldisiloxane and the like.

  The blending amount of the component (D) is preferably in the range of 0 to 8.0 parts by weight, more preferably 0.05 to 2.0 parts by weight with respect to 100 parts by weight in total of the components (A) and (B). . If it is 8.0 mass parts or less, since there is no possibility that curability may fall, it is preferable.

<(E) component>
Component (E) is an addition reaction catalyst. Specific examples include chloroplatinic acid, an alcohol solution of chloroplatinic acid, a reaction product of chloroplatinic acid and alcohol, a reaction product of chloroplatinic acid and an olefin compound, a reaction product of chloroplatinic acid and a vinyl group-containing siloxane, Examples thereof include platinum-based catalysts such as platinum-olefin complexes and platinum-vinyl group-containing siloxane complexes, and platinum group metal-based catalysts such as rhodium complexes and ruthenium complexes. Moreover, what melt | dissolved and disperse | distributed these things to solvents, such as isopropanol and toluene, silicone oil, etc. can be used.

  Component (E) is preferably added in an amount of 5 to 2,000 ppm, particularly 10 to 500 ppm as a noble metal component (platinum group metal) with respect to a total of 100 parts by mass of components (A) and (B). If it is 5 ppm or more, there is no fear that the curability, the crosslinking density, and the holding power are lowered, and if it is 2,000 ppm or less, the usable time of the treatment bath is not likely to be shortened, which is preferable.

<(F) component>
The component (F) is an organic solvent. Specific examples include aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as hexane, heptane, octane, isooctane, decane, cyclohexane, methylcyclohexane, and isoparaffin, industrial gasoline, petroleum benzine, and solvent. Hydrocarbon solvents such as naphtha, ketone solvents such as acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 2-heptanone, 4-heptanone, methyl isobutyl ketone, diisobutyl ketone, acetonyl acetone, cyclohexanone, Ester solvents such as ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, 1,2-dimethoxyethane, 1,4 Ether solvents such as dioxane, 2-methoxyethyl acetate, 2-ethoxyethyl acetate, propylene glycol monomethyl ether acetate, solvents having an ester group and an ether group, such as 2-butoxyethyl acetate, hexamethyldisiloxane, Examples thereof include siloxane solvents such as octamethyltrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, tris (trimethylsiloxy) methylsilane, tetrakis (trimethylsiloxy) silane, and mixed solvents thereof.

  Among these, aliphatic hydrocarbon solvents such as hexane, heptane, isooctane, octane, decane, cyclohexane, methylcyclohexane, and isoparaffin are preferable. A mixed solvent of an aliphatic hydrocarbon solvent and an ether solvent, an ester solvent, a solvent having both an ether group and an ester group, or the like is also preferable.

  The silicone pressure-sensitive adhesive composition is produced by mixing and dissolving the component (A), the component (B), the component (C), the component (D) and the component (F), and optional components described later. When producing the adhesive film of the present invention, the mixture is further diluted with an organic solvent as necessary, and the component (E) is added and mixed, and applied to the above-mentioned various substrate films. .

  In addition, a part or all of the components (A) and (B) are partly removed in the presence of a base catalyst and if necessary in order to remove hydroxyl groups bonded to silicon atoms remaining on them by dehydration condensation. Alternatively, the product obtained after reacting for a predetermined time in the presence of all the components (F) can also be used. Examples of the base catalyst include metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, and calcium hydroxide, carbonates such as sodium carbonate and potassium carbonate, bicarbonates such as sodium bicarbonate, sodium methoxide, Examples thereof include metal alkoxides such as potassium butoxide, organic metals such as butyl lithium, complexes of potassium hydroxide and siloxane, ammonia gas, aqueous ammonia, nitrogen compounds such as methylamine, trimethylamine and triethylamine. Of these, ammonia gas and aqueous ammonia are preferred.

  In this case, the temperature can be 20 to 150 ° C. Usually, it may be carried out at room temperature to the reflux temperature of the component (F). The time is not particularly limited, but is 0.5 to 10 hours, preferably 1 to 6 hours.

  Further, after the reaction is completed, a neutralizing agent for neutralizing the base catalyst may be added as necessary. Examples of the neutralizing agent include acidic gases such as hydrogen chloride and carbon dioxide, organic acids such as acetic acid, octylic acid and citric acid, and mineral acids such as hydrochloric acid, sulfuric acid and phosphoric acid.

In addition to the components (A) to (F), an optional component can be added to the silicone pressure-sensitive adhesive composition. Specifically, for example, non-reactive organopolysiloxanes containing no alkenyl groups, such as dimethylpolysiloxane and dimethyldiphenylpolysiloxane, organopolysiloxanes containing one or two SiH groups in the molecule, further phenolic, Antioxidants such as quinone, amine, phosphorus, phosphite, sulfur, and thioether, light stabilizers such as hindered amine, triazole, and benzophenone, phosphate ester, halogen, phosphorus, and antimony Examples thereof include flame retardants such as those, antistatic agents such as cationic activators, anionic activators, and nonionic activators, dyes, and pigments.
In order to reduce the viscosity during coating, aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as hexane, heptane, octane and isoparaffin, and ketones such as methyl ethyl ketone and methyl isobutyl ketone The silicone pressure-sensitive adhesive composition can be mixed with a solvent, an ester solvent such as ethyl acetate or isobutyl acetate, an ether solvent such as diisopropyl ether or 1,4-dioxane, or a mixed solvent thereof.

  In addition, as a means to give the target adhesive force, it can achieve by adjusting the alkenyl group of the said (A) component, or adjusting the ratio of (A) and (B) component.

  The adhesive film of the present invention has an initial adhesive strength of 0.2 to 40 N / m measured by a 180 ° peeling test method in accordance with JIS Z 0237, and the initial adhesive strength after being bonded and stored at 100 ° C. for 48 hours. A silicone pressure-sensitive adhesive composition having a pressure-sensitive adhesive strength of 300% or less can be produced by a method for producing a pressure-sensitive adhesive film including a step of forming a pressure-sensitive adhesive layer on at least one surface of a base film. In this case, as the silicone pressure-sensitive adhesive composition, the above components (A) to (F) can be used. In addition, the above-mentioned arbitrary components can be added.

  The silicone adhesive composition may be applied using a known coating method, such as a comma coater, lip coater, roll coater, die coater, knife coater, blade coater, rod coater, kiss coater, gravure coater. , Screen coating, dip coating, cast coating, spray coating and the like.

  The curing conditions can be 30 seconds to 3 minutes at 80 to 130 ° C., but are not limited thereto.

  The pressure-sensitive adhesive film may be produced by directly applying the pressure-sensitive adhesive composition to the base film, or after coating the release film or release paper on which release coating has been applied, followed by curing. You may manufacture by the transcription | transfer method bonded to a material. In order to protect the pressure-sensitive adhesive layer when the pressure-sensitive adhesive film of the present invention is stored and transported, a protective film can be provided on the pressure-sensitive adhesive layer as necessary.

  Moreover, in order to improve the adhesiveness of a base film and an adhesive layer, you may perform a primer process, a corona process, an etching process, a plasma process, and a sandblast process. Of these, corona treatment is preferred. When the component (A) of the silicone pressure-sensitive adhesive composition to be described later has a phenyl group, the adhesion may be good without performing primer treatment, and in that case, a configuration without a primer layer may be adopted. .

  The surface opposite to the pressure-sensitive adhesive layer surface of the pressure-sensitive adhesive film is preferably subjected to surface treatment such as scratch prevention, stain prevention, fingerprint adhesion prevention, antiglare, antireflection, antistatic treatment and the like. In this case, each surface treatment may be performed after the pressure-sensitive adhesive layer is applied to the base film, or the pressure-sensitive adhesive layer may be applied after the surface treatment.

  Examples of the scratch prevention treatment (hard coat treatment) include treatment with hard coat agents such as acrylate, silicone, oxetane, inorganic, and organic-inorganic hybrid.

  Examples of the antifouling treatment include treatment with an antifouling treatment agent such as fluorine, silicone, ceramic, and photocatalyst.

  Examples of the antireflection treatment include wet treatment by application of an antireflective agent such as fluorine or silicone, and dry treatment by vapor deposition or sputtering.

  Examples of the antistatic treatment include treatment with an antistatic agent such as a surfactant, silicone, organic boron, conductive polymer, metal oxide, and vapor deposition metal.

  In the method for producing a pressure-sensitive adhesive film of the present invention, the initial pressure-sensitive adhesive strength of the silicone pressure-sensitive adhesive composition is 0.4 to 20 N / m, and the pressure-sensitive adhesive strength after being bonded and stored at 80 ° C. for 48 hours is It is preferable to use a silicone adhesive composition having an initial adhesive strength of 200% or less.

  The pressure-sensitive adhesive film of the present invention is also suitable for protective films for producing various optical films and protective films for producing electronic components. For example, an adhesive film for protection and masking when processing optical parts such as a polarizing plate and a light diffusing plate, a heat-resistant masking tape when processing electronic parts such as a flexible printed wiring board, and the like.

  In addition, television receivers, computer monitors, monitors for personal digital assistants, monitors for monitoring, video cameras, digital cameras, mobile phones, personal digital assistants, displays for instrument panels of automobiles, instruments for various facilities, devices and equipment It can be used for various touch panels and flat panel displays (FPD) for displaying characters, symbols, images, etc., such as panel displays, automatic ticket vending machines, and automatic teller machines.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, it is not limited to a following example. In addition, the part and% in an example show the mass part and the mass%, and a characteristic value shows the measured value by the following test method. Me represents a methyl group, Vi represents a vinyl group, and Ph represents a phenyl group. The viscosity is an absolute viscosity at 25 ° C. measured by a rotational viscometer.

<Initial adhesive strength>
The silicone pressure-sensitive adhesive composition solution was applied to a polyethylene terephthalate film having a thickness of 23 μm using an applicator so that the thickness after curing was 30 μm.
It was heated and cured under the conditions of minutes to produce an adhesive film. A tape obtained by cutting this adhesive film to a width of 50 mm was attached to a stainless steel plate, and pressure-bonded by reciprocating a roller covered with a rubber layer having a weight of 2 kg. After leaving at room temperature for about 20 hours, measure the force (N / 50mm) required to peel off the tape from the stainless steel plate at an angle of 180 ° at a speed of 300mm / min using a tensile tester and multiply by 20 times. Converted to N / m.

<Adhesive strength over time>
An adhesive film was prepared by the same method as the initial adhesive strength evaluation. A tape obtained by cutting this adhesive film to a width of 50 mm was attached to a stainless steel plate, and pressure-bonded by reciprocating a roller covered with a rubber layer having a weight of 2 kg. After standing at 80 ° C. for 2 days or at 100 ° C. for 2 days, the temperature is returned to room temperature, and the force required to peel the tape from the stainless steel plate at an angle of 180 ° at a speed of 300 mm / min using a tensile tester (N / 50 mm), and converted to N / m by multiplying by 20.

<Removability>
After applying the silicone adhesive composition solution to a polyethylene terephthalate film having a thickness of 23 μm using an applicator so that the thickness after curing is 30 μm, the film is heated and cured at 130 ° C. for 1 minute to form an adhesive film. Was made. This film was cut into a size of 10 cm × 20 cm and attached to a glass plate by hand from the short side toward the long side. After leaving at 100 ° C. for 2 days, the attached adhesive film was peeled off from the glass plate by hand and evaluated according to the following criteria.
The evaluation criteria are as follows.
○: The film can be easily peeled off by hand, and the film does not remain bent or bent.
Δ: The film can be peeled off by hand, but the film remains bent or bent and there is no adhesive residue.
X: The film can be peeled off by hand, but the film remains bent or bent, with some glue residue.

<Bubble entrainment>
An adhesive film was prepared in the same manner as the removability test. This film was cut into a size of 10 cm × 20 cm and attached to a glass plate by hand from the short side toward the long side. At this time, the state of bubble entrainment was observed.
The evaluation criteria are as follows.
○… There is no entrainment of bubbles, and it can be applied well.
Δ: Bubbles are involved, but the bubbles can be easily pushed out of the film with a finger.
X: Bubbles are involved, and bubbles cannot be pushed out from the top of the film with fingers.

<Base material adhesion>
When using a pressure-sensitive adhesive film prepared by applying a silicone pressure-sensitive adhesive to a polyethylene terephthalate film having a thickness of 23 μm, the primer “None” and the coating amount after curing the primer composition are 0.2 g / m ² And when cured using an adhesive film prepared by applying a silicone adhesive on the primer layer, the primer is “present”. Indicated. This adhesive film was aged for 7 days under the conditions of 25 ° C./50% RH. Thereafter, the pressure-sensitive adhesive layer was damaged with a nail, and this portion was rubbed with the belly of the finger to examine whether the pressure-sensitive adhesive layer was peeled off from the base film. In this primer treatment, a condensed silicone primer composition comprising diorganopolysiloxane having a hydroxyl group terminal, organohydrogenpolysiloxane and dioctyltin diacetate as a condensation reaction catalyst was used.
The evaluation criteria are as follows.
○ ・ ・ ・ No peeling.
Δ: Part peels.
X: The whole peels off.

Example 1
Raw rubber-like vinyl group and phenyl group-containing dimethylpolysiloxane A represented by the following formula (viscosity when dissolved in toluene to a concentration of 30% is 18 Pa · s, vinyl group content 0.15 mol% , Phenyl group content 1.5 mol%) (90 parts):
ViMe ₂ SiO (ViMeSiO) _x (Me ₂ SiO) _y (Ph ₂ SiO) _z SiMe ₂ Vi (A) (x = 10, y = 3, 928, z = 60),
A 60% toluene solution (16.7 parts) of polysiloxane B (Me ₃ SiO _0.5 unit / SiO ₂ unit = 0.85) composed of Me ₃ SiO _0.5 units and SiO ₂ units, and toluene (60. 0 parts). Furthermore, an organohydrogenpolysiloxane C having a SiH group of the following formula (1.15 parts): Me ₃ SiO (HMeSiO) ₄₀ SiMe ₃ , ethynylcyclohexanol (0.20 parts) as component (D) is added, Mixed.

Addition reaction catalyst E (0...) Which is a toluene solution of a platinum-vinyl group-containing siloxane complex containing toluene (50 parts) in the above mixture (siloxane content of about 60%) (100 parts) and 0.5% by mass of platinum. 5 parts) was added and further mixed to prepare a silicone pressure-sensitive adhesive composition solution having a siloxane content of about 40%.
Each test was done according to the above-mentioned method about the obtained silicone adhesive composition.

(Examples 2 to 13)
The table shows the type of dimethylpolysiloxane A (the content of vinyl group and phenyl group is changed), the mixing ratio of A and polysiloxane B consisting of Me ₃ SiO _0.5 units and SiO ₂ units, and the amount of C added. To obtain a mixture of Examples 2-13.

Add toluene (50 parts) to the mixture (about 60% siloxane content) (100 parts) and a toluene solution (0.5 parts) of a platinum-vinyl group-containing siloxane complex containing 0.5% by mass platinum content. Further, the mixture was further mixed to prepare a silicone pressure-sensitive adhesive composition solution having a siloxane content of about 40%.
Each test was done about the obtained silicone adhesive composition according to the above-mentioned method.

(Comparative Examples 1-9)
Mixtures of Comparative Examples 1 to 9 with the kind of dimethylpolysiloxane A and the mixing ratio of polysiloxane B composed of A and Me ₃ SiO _0.5 units and SiO ₂ units and the addition amount of C as shown in Table 1. Got.

Addition reaction catalyst E (0...) Which is a toluene solution of a platinum-vinyl group-containing siloxane complex containing toluene (50 parts) in the above mixture (siloxane content of about 60%) (100 parts) and 0.5% by mass of platinum. 5 parts) was added and further mixed to prepare a silicone pressure-sensitive adhesive composition solution having a siloxane content of about 40%.
Each test was done according to the above-mentioned method about the obtained silicone adhesive composition.

  The composition content of each silicone pressure-sensitive adhesive composition is shown in Table 1.

  Table 2 shows the adhesive properties of the adhesive films obtained from the respective silicone adhesive compositions.

  From Tables 1 and 2, it can be seen that Comparative Example 4 in which the initial adhesive strength does not satisfy the requirements of the present invention has low bubble entrainment properties and poor substrate adhesion without a primer. It can be seen that Comparative Examples 1 to 3, 8, and 9 that do not satisfy the conditions are poor in re-peelability after heating, and the substrate adhesion is poor without a primer. On the other hand, the present invention has a low bubble entrainment property, is excellent in removability, and is clearly suitable for industrial use.

  In addition, this invention is not limited to the said Example. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

Claims (7)

  A pressure-sensitive adhesive film comprising a base film and a pressure-sensitive adhesive layer formed on at least one side of the base film, wherein the pressure-sensitive adhesive layer was measured by a 180 ° peeling test method according to JIS Z 0237. A base material film was coated with a silicone adhesive composition having an initial adhesive strength of 0.2 to 40 N / m and an adhesive strength of 300% or less of the initial adhesive strength after being bonded and stored at 100 ° C. for 48 hours. An adhesive film characterized by comprising: The adhesive film according to claim 1,
A silicone adhesive composition having an initial adhesive strength of 0.4 to 20 N / m and an adhesive strength of not more than 200% of the initial adhesive strength after being bonded and stored at 80 ° C. for 48 hours is applied to the base film. A pressure-sensitive adhesive film characterized by being coated.   The pressure-sensitive adhesive film according to claim 1 or 2, wherein the pressure-sensitive adhesive layer has a thickness of 2 to 200 µm. The silicone pressure-sensitive adhesive composition is
(A) Among all organic groups having two or more alkenyl groups in one molecule and bonded to a silicon atom, the phenyl group is contained in an amount of 0 to 12 mol%, and the alkenyl group is contained in an amount of 0.15 to 7.5 mol. %, And a diorganopolysiloxane having a viscosity at 25 ° C. of 100,000 mPa · s or more: 90 to 40 parts by mass,
(B) Organopolysiloxane containing R ¹ ₃ SiO _0.5 unit and SiO ₂ unit and having a R ¹ ₃ SiO _0.5 unit / SiO ₂ unit molar ratio of 0.6 to 1.7 (R ¹ Is a monovalent hydrocarbon group having 1 to 10 carbon atoms.): 10 to 60 parts by mass,
(C) Organohydrogenpolysiloxane containing 3 or more SiH groups in one molecule: (A), an amount such that the molar ratio of SiH groups to alkenyl groups in component (B) is 0.5 to 10,
(D) Control agent: 0 to 8.0 parts by mass with respect to 100 parts by mass in total of the components (A) and (B),
(E) Addition reaction catalyst: 5 to 2,000 ppm as a noble metal component with respect to a total of 100 parts by mass of component (A) and component (B),
(F) Organic solvent: 25 to 900 parts by mass with respect to 100 parts by mass in total of the components (A) and (B),
The pressure-sensitive adhesive film according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive composition contains a silicone pressure-sensitive adhesive composition.   The phenyl group content of the component (A) is 1 to 9 mol%, and no primer layer is provided between the base film and the pressure-sensitive adhesive layer. The adhesive film as described. A method for producing an adhesive film,
Silicone having an initial adhesive strength of 0.2 to 40 N / m measured by a 180 ° peel test method according to JIS Z 0237 and an adhesive strength of 300% or less of the initial adhesive strength after being bonded and stored at 100 ° C. for 48 hours The manufacturing method of the adhesive film characterized by including the process of apply | coating an adhesive composition on the at least single side | surface of a base film, and forming an adhesive layer. It is a manufacturing method of the adhesive film according to claim 6,
The silicone pressure-sensitive adhesive composition having an initial adhesive strength of 0.4 to 20 N / m as the silicone pressure-sensitive adhesive composition, and a pressure-sensitive adhesive strength after bonding and storage at 80 ° C. for 48 hours of 200% or less of the initial adhesive strength. A method for producing an adhesive film, characterized by using a product.