WO2012005221A1 - Method for producing multilayer sheet, and multilayer sheet - Google Patents

Abstract

Disclosed is a method for producing a multilayer sheet, wherein at least two active energy ray-curable resin layers are collectively polymerized by irradiation of an active energy ray. The active energy ray-curable resin layers include an active energy ray-curable resin layer (A), which is formed from a resin composition (A) that contains an active energy ray-curable acrylic monomer, and an active energy ray-curable resin layer (B), which is formed from a resin composition (B) that contains an active energy ray-curable acrylic monomer and a solid component that is composed of a urethane polymer. The solid component that is composed of a urethane polymer has a weight average molecular weight of 10,000 or more, and the solid component amount (the polymerized fraction) of the solid component that is composed of a urethane polymer in the resin composition (B) is 35% by mass or more. The solid component amount (the polymerized fraction) of two adjacent active energy ray-curable resin layers is set to be 50% by mass or more in total. Consequently, the method for producing a multilayer sheet exhibits high productivity and is capable of providing each layer with a desired function.

Description

Multilayer sheet manufacturing method and multilayer sheet

The present invention relates to a multilayer sheet polymerized (cured) by irradiation with active energy rays and a method for producing the same, and more particularly to a method for producing a multilayer sheet capable of realizing high productivity and desired characteristics.

Since a sheet cured by irradiation with active energy rays does not normally require a drying process, it has the advantages that it consumes less energy and has less environmental impact than a thermal polymerization method that requires a drying process. In addition, even if the sheet has a multilayer structure, it can be simultaneously cured to form a multilayer sheet, so that, for example, high productivity is expected as compared to the case where a multilayer sheet is produced by laminating each layer. Can do.

The multi-layer sheet configuration can realize a high function sheet as compared with a single layer sheet because each layer can share various functions. For example, Japanese Patent Application Laid-Open No. 2008-7632 discloses a method for producing a multilayer film in which two or more different ultraviolet curable resin layers are multilayer coated and then simultaneously irradiated with energy rays and simultaneously cured. ing. According to this method, for example, the base material layer and the pressure-sensitive adhesive layer can be cured simultaneously, and a pressure-sensitive adhesive sheet excellent in anchoring force between the base material layer and the pressure-sensitive adhesive layer can be realized.

Japanese Laid-Open Patent Publication No. 63-118392 discloses a method for producing a multilayer film in which two or more different ultraviolet curable resin layers are sequentially coated in a multilayer and then irradiated with ultraviolet rays to perform batch polymerization. ing. According to this method, each adjacent layer is composed of a polymer chain matrix, and the polymer chains of one layer extend through the interface into the matrix of the adjacent layer, and these adjacent layers are firmly anchored to each other. Multi-layer films can be produced.

Japanese Unexamined Patent Publication No. 2008-7632 Japanese Unexamined Patent Publication No. Sho 63-118392

However, the multilayer sheet formed by the above production method sometimes fails to obtain the effect of the characteristics imparted to each layer. As a result of intensive studies, the present inventors have found that, in the state where the active energy ray-curable resin composition layer is laminated, when a low molecular weight component that can move exists in any layer, the low molecular weight component is It has been found that the properties required for each layer of the multilayer sheet are adversely affected.
The present invention has been made to solve the above problems, and an object of the present invention is to provide a manufacturing method that is excellent in productivity and that can obtain a multilayer sheet having desired characteristics. Another object is to provide a multilayer sheet obtained by the production method.

The method for producing a multilayer sheet of the present invention is a method for producing a multilayer sheet obtained by batch polymerization of at least two active energy ray-curable resin layers with active energy rays,
At least one of the active energy ray-curable resin layers is an active energy ray-curable resin layer A formed by a resin composition A containing an active energy ray-curable acrylic monomer,
At least one of the active energy ray-curable resin layers is an active energy ray-curable resin layer B formed of a resin composition B containing an active energy ray-curable acrylic monomer and a solid component made of a urethane polymer. And
The solid component made of the urethane polymer has a weight average molecular weight of 10,000 or more, and the solid component amount (polymerization ratio) of the solid component made of the urethane polymer in the resin composition B is 35% by mass or more. ,
The two active energy ray-curable resin layers adjacent to each other are characterized in that the total amount of solid components (polymerization rate) is 50% by mass or more.

In the present invention, the urethane polymer is preferably an acryloyl group-terminated urethane polymer.

The active energy ray-curable resin layer A and the active energy ray-curable resin layer B are preferably adjacent to each other.

The multilayer sheet of the present invention is obtained by any one of the above-described production methods.

In the present invention, the layer adjacent to the active energy ray-curable resin layer B preferably has a tack at normal temperature.

According to the present invention, it is possible to provide a manufacturing method capable of obtaining a multilayer sheet in which layers having different functions are laminated without impairing the properties of each layer. And this manufacturing method is also a manufacturing method excellent in productivity. Moreover, according to this invention, the multilayer sheet obtained by this manufacturing method can be provided.

FIG. 1 is a schematic explanatory diagram for explaining a method of measuring tack.

Hereinafter, the present invention will be described in detail. In the present specification, all percentages and parts expressed by mass are the same as percentages and parts expressed by weight.
The multilayer sheet of the present invention is a sheet having at least two active energy ray-curable resin layers.
At least one of the active energy ray curable resin layers is an active energy ray curable resin layer A, and at least one of the active energy ray curable resin layers is an active energy ray curable resin layer B. The active energy ray-curable resin layer A is formed of a resin composition A containing an active energy ray-curable acrylic monomer, and the active energy ray-curable resin layer B includes an active energy ray-curable acrylic monomer and And a resin composition B containing a solid component made of a urethane polymer. The solid component made of the urethane polymer has a weight average molecular weight of 10,000 or more, and the solid component amount (polymerization ratio) of the solid component made of the urethane polymer in the resin composition B is 35% by mass or more. . Furthermore, the amount of solid components (for the polymerization rate) of two active energy ray-curable resin layers adjacent to each other needs to be 50% by mass or more in total.

In the present invention, the laminated active energy ray-curable resin layer is batch-polymerized with active energy rays to form a multilayer sheet. For example, a multilayer sheet can be formed by batch polymerization by irradiating active energy rays to two or more active energy ray-curable resin layers.

In the present invention, when the active energy ray curable resin composition has a partially polymerized prepolymer component, the amount of solid component (polymerization rate) in the resin composition (hereinafter also referred to as “partial polymer”) Can be obtained as follows. That is, first, about 0.5 g of the partial polymer is precisely weighed (weight of the partial polymer before drying). Next, the weight after the precisely weighed partially polymerized product is dried at 130 ° C. for 2 hours is precisely weighed, and the amount of decrease in the weight (volatile matter (weight of unreacted monomer)) changed by drying is determined. By substituting the obtained value into the following formula, the solid component amount (polymerization rate) (%) is determined.
Solid component amount (polymerization rate) (%) = {1− (weight reduction) / (weight of partially polymerized product before drying)} × 100

The active energy ray-curable resin layer A of the present invention is a layer using the resin composition A, and the resin composition A contains an active energy ray-curable acrylic monomer. Examples of the active energy ray-curable acrylic monomer include ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) acrylate, t -Butyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isononyl (meth) acrylate, dodecyl (meth) acrylate, n-octadecyl (meth) acrylate, or Carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, and crotonic acid; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, ( Hydroxyl group-containing monomers such as 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) -methyl acrylate; alicyclic rings such as cyclohexyl (meth) acrylate and isobornyl acrylate Monomers having the formula structure; acid anhydride monomers such as maleic anhydride and itaconic anhydride; sulfonic acid group-containing monomers such as 2-acrylamido-2-methylpropanesulfonic acid and sulfopropyl acrylate; 2-hydroxyethylacryloyl Phosphate-containing monomers such as Sufeto like. In addition, amide monomers such as N-substituted (meth) acrylamide such as (meth) acrylamide and N-methylolacrylamide, N- (meth) acryloyloxymethylenesuccinimide, N- (meth) acryloyl-6-oxyhexamethylenesuccinimide, Succinimide monomers such as N- (meth) acryloyl-8-oxyoctamethylenesuccinimide; vinyl monomers such as vinyl acetate, N-vinylpyrrolidone, N-vinylcarboxylic acid amides, N-vinylcaprolactam; acrylonitrile, methacrylonitrile Cyanoacrylate monomers such as glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate DOO, fluorine (meth) acrylate, silicone (meth) acrylate, 2-methoxyethyl acrylate, methyl (meth) acrylate, octadecyl (meth) acrylate monomers such as acrylate. These active energy ray-curable acrylic monomers can be used alone or in combination of two or more.

Also, a polyfunctional monomer can be used as the active energy ray-curable acrylic monomer. By using a polyfunctional monomer, for example, the cohesive force can be increased, and desired physical properties can be obtained.

Examples of multifunctional monomers include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and pentaerythritol. Di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, allyl (meth) acrylate, vinyl (meta ) Acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, urethane acrylate, butyl di (meth) acrylate, hexyl di (meth) acrylate, etc. It can be mentioned.

The amount of the polyfunctional monomer used can be appropriately determined according to the purpose and application of the obtained polymer member. For example, when the obtained polymer member requires adhesive properties, the amount of the polyfunctional monomer used is 2% by mass or less (for example, 0.01% by mass or more and 2.0% by mass with respect to the total amount of monomer components). Or less), and more preferably 0.02% by mass or more and 1% by mass or less. If the amount of the polyfunctional monomer used exceeds 2% by mass, the cohesive force becomes too high and the pressure-sensitive adhesiveness may be lowered. Moreover, when there are too few usage-amounts of a polyfunctional monomer, if it is less than 0.01 mass%, the effect of a cohesion force improvement may not be acquired, for example.

When hard physical properties are required for the obtained polymer member, for example, when physical properties (hardness) suitable for film use or hard coat use are required, the amount of the polyfunctional monomer used is the total amount of monomer components. It is preferably 95% by mass or less (for example, 0.01% by mass or more and 95% by mass or less), more preferably 1% by mass or more and 70% by mass or less. If the amount of the polyfunctional monomer used exceeds 95% by mass with respect to the total amount of the monomer components, the curing shrinkage at the time of polymerization may increase and a uniform film-like or sheet-like polymer member may not be obtained. The member may become very brittle. Moreover, when there is too little usage-amount of a polyfunctional monomer (for example, it is less than 0.01 mass%), there exists a possibility that the polymer member which has sufficient solvent resistance and heat resistance may not be obtained.

In the present invention, the term “film” includes a sheet, and the term “sheet” includes a film. Further, in the present invention, when “(meth) acryl” is displayed, such as (meth) acrylate and (meth) acrylic acid, it means acrylic and / or methacrylic. In addition, when the same expression is used in the present invention, it has the same meaning as described above unless otherwise specified. Furthermore, even when “acrylic” is simply displayed, there is no particular notice, and if there is no problem in general common sense, it will be understood to include methacryl.

The active energy ray-curable resin layer B of the present invention is a layer formed using the resin composition B, and the resin composition B contains an active energy ray-curable acrylic monomer and a solid component composed of a urethane polymer. To do.

As the active energy ray-curable acrylic monomer, the same active energy ray-curable acrylic monomer that constitutes the resin composition A described above can be used. Moreover, about the usage-amount, it can use by the same usage-amount.

The solid component made of urethane polymer has a weight average molecular weight (Mw) of 10,000 or more, preferably 20,000 or more, and more preferably 30,000 or more. When the weight average molecular weight (Mw) of the solid component made of the urethane polymer is less than 10,000, the polymer component may diffuse into the adjacent layers, and desired characteristics may not be obtained.

Urethane polymer can be obtained by reacting polyol and polyisocyanate. A catalyst may be used when the hydroxyl group of the polyol and the polyisocyanate are reacted. As the catalyst, a catalyst generally used in a urethane reaction can be used. For example, dibutyltin dilaurate, octoate tin, 1,4-diazabicyclo (2,2,2) octane and the like can be used.

As the polyol, those having two or more hydroxyl groups in one molecule are preferable. Examples of the low molecular weight polyol include divalent alcohols such as ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, and hexamethylene glycol, and trivalent or tetravalent alcohols such as trimethylolpropane, glycerin, and pentaerythritol. It is done.

Examples of the polymer polyol include polyether polyol, polyester polyol, acrylic polyol, epoxy polyol, carbonate polyol, and caprolactone polyol. Among these, polyether polyol, polyester polyol, and carbonate polyol are preferable.

Examples of polyether polyols include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Examples of the polyester polyol include alcohols such as the above divalent alcohols, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol, and divalents such as adipic acid, azelaic acid, and sebacic acid. The polycondensation product with a base is mentioned. In addition, lactone ring-opening polymer polyol polycarbonate diol such as polycaprolactone is used. Examples of the acrylic polyol include a copolymer of a monomer having a hydroxyl group such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate, and a copolymer of a hydroxyl group-containing substance and an acrylic monomer. . Examples of the epoxy polyol include amine-modified epoxy resins.

In the present invention, the above polyols can be used alone or in combination of two or more.

Examples of the polyisocyanate used in the present invention include aromatic, aliphatic and alicyclic diisocyanates, and dimers and trimers of these diisocyanates.

Examples of aromatic, aliphatic, and alicyclic diisocyanates include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, and 1,5-naphthylene. Range isocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, butane-1,4-diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, cyclohexane-1 , 4-diisocyanate, dicyclohexylmethane-4,4-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohex Emissions, methylcyclohexane diisocyanate, m- tetramethylxylylene diisocyanate, and the like. Further, dimers and trimers of these diisocyanates, polyphenylmethane polyisocyanate, and the like are also used. Examples of the trimer of isocyanate include isocyanurate type, burette type, and allophanate type, and can be used as appropriate.

These isocyanates can be used alone or in combination of two or more. Further, from the viewpoints of urethane reactivity, compatibility with acrylic, and the like, the type and combination of isocyanates can be selected as appropriate.

In the present invention, the use amounts of the polyol component and the polyisocyanate component for forming the urethane polymer are not particularly limited. For example, the use amount of the polyol component is NCO / OH (equivalent to the polyisocyanate component). Ratio) is preferably 0.8 to 3.0, more preferably 1.0 to 3.0. When NCO / OH is 0.8 or more and 3.0 or less, a multilayer sheet capable of exhibiting various functions of the object of the present invention can be obtained without lowering the molecular weight.

The urethane polymer is preferably an acryloyl group-terminated urethane polymer. For example, it is preferable that a hydroxyl group-containing acrylic monomer is added to the urethane polymer so that the polymer terminal is an acryloyl group. By introducing an acryloyl group into the molecule of the urethane polymer, it is possible to impart copolymerizability with an acrylic monomer.

As the hydroxyl group-containing acrylic monomer, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxyhexyl (meth) acrylate, or the like is used. The addition amount of the hydroxyl group-containing acrylic monomer is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.1 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the urethane polymer. It is.

In the present invention, the urethane polymer in the resin composition B is contained so that the solid component amount (polymerization ratio) of the urethane polymer is 35% by mass or more. If the solid component amount (polymerization rate) composed of the urethane polymer in the resin composition B is less than 35% by mass, for example, an adhesive layer is laminated on the active energy ray-curable resin layer B formed from the resin composition B. In such a case, adhesive force (tack) may be generated on the active energy ray-curable resin layer B side.

The multilayer sheet of the present invention has an active function ray curable resin layer A and an active energy ray curable resin layer B other than the two layers in order to give further functions or to obtain a more economical laminated sheet. Other active energy ray-curable resin layers made of other resin compositions that are cured (polymerized) by energy beam irradiation to form a polymer layer can be provided.

Examples of other resin compositions include, but are not limited to, actives containing monomers such as acrylic, rubber, vinyl alkyl ether, silicone, polyester, polyamide, urethane, fluorine, and epoxy. An energy beam curable composition is mentioned.

In the present invention, in order to cure the active energy ray-curable resin composition, a photopolymerization initiator is added to each of the resin compositions.

As the photopolymerization initiator used here, various photopolymerization initiators can be used. For example, benzoin methyl ether, benzoin isopropyl ether, 2,2-dimethoxy-1,2-diphenylethane-1 Benzoin ether photopolymerization initiators such as -one; substituted benzoin ether photopolymerization initiators such as anisole methyl ether; 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxy-cyclohexyl Substituted acetophenone photopolymerization initiators such as phenyl ketone; Substituted alpha-ketol photopolymerization initiators such as 2-methyl-2-hydroxypropiophenone; Aromatic sulfonyl chloride photopolymerization initiators such as 2-naphthalenesulfonyl chloride; 1-phenyl-1,1-pro Photoactive oxime photopolymerization initiators such as Ndion-2- (o-ethoxycarbonyl) -oxime; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine Examples thereof include acylphosphine oxide photopolymerization initiators such as oxide.

As the photopolymerization initiator, for example, “Irgacure 651” (2,2-dimethoxy-1,2-diphenylethane-1-one) manufactured by Ciba Specialty Chemicals can be obtained commercially.

The amount of the photopolymerization initiator used is, for example, 0.01 parts by mass or more and 5 parts by mass with respect to 100 parts by mass of all the monomer components in each resin composition forming each active energy ray-curable resin layer. The content is preferably 0.05 or less, more preferably 0.05 parts by mass or more and 3 parts by mass or less.

In addition, various additives may be included in the resin composition forming each active energy ray-curable resin layer. Examples of the additive include a surfactant, a tackifier, a plasticizer, a filler, an anti-aging agent, an antioxidant, and a colorant (pigment, dye, etc.).

In the present invention, the material forming each layer constituting the multilayer sheet preferably has an appropriate viscosity. For example, in a viscosity measurement with a B-type viscometer, it is preferably 0.3 to 40 Pa · s at 25 ° C. . If it has an appropriate viscosity, a layer shape such as a coating layer can be easily formed before irradiating active energy rays. As a method for adjusting the viscosity, for example, the active energy ray-curable acrylic monomer is prepolymerized, and a certain amount of the monomer is polymerized as a partially polymerized product (solid component) to give the resin composition a viscosity. be able to. Alternatively, the viscosity can be adjusted by forming a urethane polymer in an active energy ray-curable acrylic monomer and preparing it as a solid component (partial polymer) made of a urethane polymer. Specifically, for example, after the polyol is dissolved in the active energy ray-curable acrylic monomer, polyisocyanate or the like is added and reacted to form a urethane polymer-acrylic monomer mixture to adjust the viscosity. Can do. In addition, the viscosity can be adjusted by adding other polymer components (partially polymerized) or the like to the active energy ray-curable acrylic monomer.

When imparting viscosity to the resin composition, the solid component amount of the partially polymerized product in each resin composition (for the polymerization rate) is preferably about 2 to 80% by mass, although it depends on the molecular weight of the polymer. More preferably, it is 5 to 70% by mass. By setting the viscosity of the resin composition within the above range, it is easy to form a sheet shape and to perform a laminating operation.

The resin composition A forming the active energy ray-curable resin layer A may contain only the active energy ray-curable acrylic monomer, but preferably contains a partial polymer from the viewpoint of coating workability. . When a partial polymer is contained, the solid component amount (polymerization ratio) of the partial polymer in the active energy ray-curable resin layer A is preferably 2% by mass or more, and more preferably 5% by mass or more. Further, the upper limit is preferably 50% by mass or less, and more preferably less than 35% by mass.
Further, in the active energy ray-curable resin layer B, the solid component amount (polymerization rate) of the solid component (partial polymer) composed of the urethane polymer in the resin composition B forming the active energy ray-curable resin layer B Needs to be 35% by mass or more, preferably 40% by mass or more and 80% by mass or less. When the solid component amount (polymerization rate) of the solid component made of urethane polymer is less than 35% by mass, the urethane component amount decreases, for example, the active energy ray-curable resin layer B formed from the resin composition B has an adhesive layer. May cause adhesive force (tack) to appear on the active energy ray-curable resin layer B side.

In the present invention, the total amount of solid components (polymerization ratio) of two adjacent active energy ray-curable resin layers adjacent to each other needs to be 50% by mass or more, and preferably 70% by mass or more. . If the total amount of solid components (polymerization rate) of two adjacent layers is less than 50% by mass, the degree of mutual diffusion of low molecular weight components between the layers increases, which adversely affects functional separation in each layer. There is a risk.

As described above, the multilayer sheet of the present invention has at least two active energy ray-curable resin layers, at least one of which is an active energy ray-curable resin layer A (indicated as “A layer”). And at least one of them is an active energy ray-curable resin layer B (indicated as “B layer”). The multilayer sheet can have a desired number of layers, and the A layer and the B layer can also have a predetermined number of layers. As the layer structure, an appropriate layer structure such as A layer / B layer, A layer / B layer / A layer, A layer / A layer / B layer, A layer / B layer / B layer, or the like can be adopted. Moreover, when laminating | stacking other layers other than A layer and B layer, according to the characteristic of this other layer, it can laminate | stack suitably in positions, such as an interlayer and an outermost layer.
For example, in the case of imparting an adhesive function to the A layer and imparting a hardness (film-like function) to the B layer, the A layer (adhesive layer) / B layer (base material layer), A layer (adhesive layer) / If the layer structure such as B layer (base material layer) / A layer (adhesive layer) can be used, or if the B layer is also provided with an adhesive function, A layer (adhesive layer) / B layer (adhesive) It is also possible to adopt a layer structure such as (layer). Thus, it can also be used for uses such as single-sided adhesive tapes and double-sided adhesive tapes.
In the present invention, it is preferable that the A layer and the B layer are adjacent to each other. When the other layers other than the A layer and the B layer are stacked, they are sequentially adjacent to the stacked structure in which the A layer and the B layer are stacked. It is preferable to laminate them.

The multilayer sheet of the present invention is obtained by batch polymerization of the laminated active energy ray-curable resin layers with active energy rays. For example, it is formed by irradiating two or more active energy ray-curable resin layers with active energy rays. Examples of active energy rays used here include ionizing radiation such as α rays, β rays, γ rays, neutron rays, and electron rays, radiation such as ultraviolet rays, and visible light. The active energy ray can be appropriately selected according to the type of the photopolymerization initiator.

The apparatus used for the irradiation of the active energy ray can be appropriately selected. For example, a fluorescent chemical lamp, a black light, a sterilization lamp, a metal halide lamp, an LED (Light Emitting Diode) lamp, and an EB (Electron Beam) irradiation. A device or the like can be used.

Irradiation amount such as ultraviolet rays can be arbitrarily set according to required characteristics. In general, the irradiation amount of ultraviolet rays is 100 to 5,000 mJ / cm ² , preferably 1,000 to 4,000 mJ / cm ² , more preferably 2,000 to 3,000 mJ / cm ² . When the irradiation amount of ultraviolet rays is less than 100 mJ / cm ² , a sufficient polymerization rate may not be obtained, and when it is more than 5,000 mJ / cm ² , deterioration may be caused.

The multilayer sheet of the present invention comprises an active energy ray-curable resin composition (for example, resin composition A and resin composition B) adjusted to an appropriate viscosity, and a resin composition coating layer having a multilayer structure using a multilayer die. Can be formed on a support or the like and irradiated with active energy rays.

Alternatively, an active energy ray-curable resin composition adjusted to an appropriate viscosity is applied on a support or the like, and then active energy ray hardening adjusted to another appropriate viscosity is applied on the coating layer. The resin composition coating layer having a multilayer structure is applied by repeating the work of coating the active energy ray-curable resin composition adjusted to an appropriate viscosity as many times as necessary. After forming, a multilayer sheet can be manufactured by irradiating active energy rays.

Alternatively, after adjusting different active energy ray-curable resin compositions to different viscosities on different supports, they are applied to form a coating layer, and these coating layers are laminated to form a multilayer resin The composition coating layer may have a structure sandwiched by a support and then irradiated with active energy rays to produce a multilayer sheet.

As the support used here, it is preferable to use a support that does not inhibit the transmission of active energy rays. Further, the surface of the support is subjected to oxidation treatment by a chemical or physical method such as corona treatment, chromic acid treatment, ozone exposure, flame exposure, high-voltage impact exposure, ionizing radiation treatment, etc., if necessary. Alternatively, a coating treatment with an undercoat agent, a release agent, or the like may be performed.

The support may be peeled off after forming the multilayer sheet, or only a part may be peeled off or may not be peeled off at all. The thickness of the support can be appropriately selected according to strength, flexibility, purpose of use and the like. For example, it is generally 1,000 μm or less (for example, 1 to 1,000 μm), preferably 1 μm or more and 500 μm or less, more preferably about 3 μm or more and 300 μm or less. The support may have a single layer structure or a laminated structure of two or more layers.

The thickness of each layer constituting the multilayer sheet of the present invention can be appropriately determined according to the purpose and the like. For example, the thickness of the active energy ray-curable resin layer A is preferably 30 μm or more, more preferably 40 μm or more, and particularly preferably 50 μm or more. If the thickness of the layer is less than 30 μm, it may be affected by the diffusion of the urethane polymer.

The thickness of the active energy ray-curable resin layer B is preferably 20 μm or more and 2.0 mm or less, more preferably 30 μm or more and 1.5 mm or less, and particularly preferably 50 μm or more and 1.0 mm or less. It is. When the thickness of the layer is 20 μm or more, the characteristics of the urethane polymer can be fully utilized. On the other hand, if it exceeds 2.0 mm, curing with active energy rays may take a long time, which may lead to deterioration in productivity.

In the method for producing a multilayer sheet of the present invention, the active energy ray-curable resin layer B is prepared by mixing an active energy ray acrylic monomer, a urethane polymer precursor, a polyol and a polyisocyanate in advance, and partially mixing them. It may be formed by applying a resin composition B containing a urethane polymer by polymerization (a certain amount), and a urethane polymer is prepared in advance and mixed with an active energy ray acrylic monomer. You may form by apply | coating the resin composition B. FIG.

In the multilayer sheet of the present invention, it is preferable that at least one of the layers adjacent to the active energy ray-curable resin layer B is a layer having tack at normal temperature. In the present invention, it is preferable that a separate function can be realized in each layer of the multilayer sheet. For example, it is preferable that a difference in tack value between adjacent layers is large. In the present invention, the normal temperature means 15 to 25 ° C.

If the production method of the present invention is used, even if two or more active energy ray-curable resin layers are collectively polymerized, each layer exhibits a desired function sharing without adversely affecting the functions required for each layer. A multilayer sheet is obtained. That is, since a multilayer sheet having various characteristics that cannot be realized with a single layer can be obtained, it can be applied to various applications. For example, it can also be set as an adhesive sheet by using a certain layer as an adhesive layer and another layer as a base material layer.

In addition, according to the present invention, by irradiating active energy rays such as ultraviolet rays and electron beams, a sheet having a multilayer structure can be polymerized at the same time, so the process is simple and the productivity is excellent. . Moreover, since a solvent etc. are not required, it is excellent also from a viewpoint of environmental protection.

That is, according to the present invention, it is possible to provide a production method for obtaining a multilayer sheet having desired characteristics. And this manufacturing method is also a manufacturing method excellent in productivity. Moreover, according to this invention, the multilayer sheet obtained by this manufacturing method can be provided.

Hereinafter, the present invention will be described in detail using examples, but the present invention is not limited thereto. In the following examples, unless otherwise specified, parts means parts by mass. The measurement methods (evaluation methods) used in the following examples are shown below.

(Measurement method and evaluation method)
(1) Measurement of molecular weight The obtained syrup (syrup-like resin composition) was dried at 130 ° C. for 2 hours to remove low molecular weight components to obtain solid components. The obtained solid component was adjusted to 0.05 mass% with a tetrahydrofuran solvent, and this solution was measured by gel permeation chromatography (GPC). “HLC-8020” manufactured by Tosoh Corporation was used as a measuring device, and TSK _gel GMH _HR- (20) manufactured by Tosoh Corporation was used as a column.

(2) Measurement of tack The obtained multilayer sheet was cut into a size of 3 cm × 3 cm to obtain a test sample. As shown in FIG. 1, a probe having a terminal diameter of 5 mm was pushed into the surface of this test sample at room temperature at a pushing speed of 300 mm / min, a pushing distance of 40 μm, and a load of 1.5 kg (step (b) in FIG. 1). ) With the rest time zero, the probe tip was pulled out at a pulling speed of 300 mm / min (step (c) in FIG. 1), and the tack (unit: N) was measured. In FIG. 1, this series of measurement operations is illustrated in the order of (a) to (d).

(Production Example 1)
In a reaction vessel equipped with a condenser, a thermometer, and a stirrer, 100 parts of cyclohexyl acrylate (CHA) as a (meth) acrylic monomer and poly (tetramethylene) glycol (PTMG-) having a number average molecular weight of 650 as a polyol are added. 650, manufactured by Mitsubishi Chemical Co., Ltd.), 73.3 parts of dibutyltin dilaurate (DBTL) as a catalyst, and 0.01 parts of hydrogenated xylylene diisocyanate (HXDI) (Mitsui Chemical Polyurethane Co., Ltd.) while stirring. 24.1 parts) was added dropwise and reacted at 65 ° C. for 10 hours to obtain a urethane polymer-acrylic monomer mixture.

Thereafter, 2.6 parts of hydroxyethyl acrylate (HEA) was added and reacted at 65 ° C. for 1 hour to obtain an acryloyl group-terminated urethane polymer-acrylic monomer mixture. Further, 0.30 part of 2,2-dimethoxy-1,2-diphenylethane-1-one (“IRGACURE 651” manufactured by Ciba Japan Co., Ltd.) was added as a photopolymerization initiator, and a coating solution (syrup) was added. I) was obtained.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 1.1, the amount of solid components (for polymerization rate) is 50 mass%, and a solid component (urethane acrylate polymer) The weight average molecular weight (Mw) was 52,000.

(Production Example 2)
A coating solution (syrup II) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 100 parts of cyclohexyl acrylate (CHA), 68.4 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 25.5 parts of added xylylene diisocyanate (HXDI) and 6.1 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 1.25, the amount of solid components (for polymerization rate) is 50 mass%, and the amount of solid components (urethane acrylate polymer) The weight average molecular weight (Mw) was 23,000.

(Production Example 3)
A coating solution (syrup III) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 100 parts of cyclohexyl acrylate (CHA), 64.1 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 26.8 parts of added xylylene diisocyanate (HXDI) and 9.2 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 1.4, the amount of solid components (for polymerization rate) is 50 mass%, and a solid component (urethane acrylate polymer) The weight average molecular weight (Mw) was 14,000.

(Production Example 4)
A coating solution (syrup IV) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 100 parts of cyclohexyl acrylate (CHA), 51.1 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 30.6 parts of added xylylene diisocyanate (HXDI) and 18.3 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 2.0, the amount of solid components (for polymerization rate) is 50 mass%, and a solid component (urethane acrylate polymer) The weight average molecular weight (Mw) was 8,000.

(Production Example 5)
A coating solution (syrup V) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 186 parts of cyclohexyl acrylate (CHA), 68.4 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 25.5 parts of added xylylene diisocyanate (HXDI) and 6.1 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 1.25, the amount of solid components (for polymerization rate) is 35 mass%, and solid components (urethane acrylate polymer) The weight average molecular weight (Mw) was 23,000.

(Production Example 6)
A coating liquid (syrup VI) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 400 parts of cyclohexyl acrylate (CHA), 68.4 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 25.5 parts of added xylylene diisocyanate (HXDI) and 6.1 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 1.25, the amount of solid components (for polymerization rate) is 20 mass%, and the amount of solid components (urethane acrylate polymer) is The weight average molecular weight (Mw) was 23,000.

(Production Example 7)
A coating solution (syrup VII) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 25 parts of cyclohexyl acrylate (CHA), 51.1 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 30.6 parts of added xylylene diisocyanate (HXDI) and 18.3 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 2.0, the amount of solid components (polymerization rate part) is 80 mass%, and a solid component (urethane acrylate polymer) The weight average molecular weight (Mw) was 8,000.

(Production Example 8)
To 100 parts of butyl acrylate (BA), 0.10 parts of 2,2-dimethoxy-1,2-diphenylethane-1-one (trade name “IRGACURE 651”, manufactured by Ciba Japan Co., Ltd.) was added. The solution was put into a four-necked flask, exposed to ultraviolet light in a nitrogen atmosphere, and partially photopolymerized to obtain a coating solution (syrup A) containing a prepolymer. The solid component (polymerization rate) was 13% by mass, and the weight average molecular weight (Mw) of the solid component (prepolymer) was 2.1 million.

(Production Example 9)
The types and amounts of (meth) acrylic monomers, polyols, catalysts, polyisocyanates and hydroxyl group-containing acrylic monomers were changed as follows, and 2 lauryl mercaptans (manufactured by Kishida Chemical Co., Ltd.) were used as chain transfer agents. A coating solution (syrup B) was obtained in the same manner as in Production Example 1 except that 0.0 × 10 ⁻² parts were added.
That is, 186 parts of cyclohexyl acrylate (CHA), 68.4 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 25.5 parts of added xylylene diisocyanate (HXDI) and 6.1 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, and is NCO / OH = 1.25, the amount of solid components (for polymerization rate) is 32 mass%, and the amount of solid components (urethane acrylate polymer) is The weight average molecular weight (Mw) was 1,200,000.

(Production Example 10)
The type and amount of (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows, and 1 lauryl mercaptan (manufactured by Kishida Chemical Co., Ltd.) was used as a chain transfer agent. A coating solution (syrup C) was obtained in the same manner as in Production Example 1, except that 0.7 × 10 ⁻¹ part was added.
That is, 186 parts of cyclohexyl acrylate (CHA), 68.4 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 25.5 parts of added xylylene diisocyanate (HXDI) and 6.1 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, NCO / OH = 1.25, the amount of solid components (for polymerization rate) is 67 mass%, and the amount of solid components (urethane acrylate polymer) The weight average molecular weight (Mw) was 330,000.

(Production Example 11)
A coating solution (syrup VIII) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 25 parts of cyclohexyl acrylate (CHA), 68.4 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 parts of dibutyltin dilaurate (DBTL), water 25.5 parts of added xylylene diisocyanate (HXDI) and 6.1 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, NCO / OH = 1.25, the amount of solid components (for polymerization rate) is 80 mass%, and a solid component (urethane acrylate polymer) The weight average molecular weight (Mw) was 23,000.

(Production Example 12)
A coating solution (syrup IX) was obtained in the same manner as in Production Example 1 except that the type and amount of the (meth) acrylic monomer, polyol, catalyst, polyisocyanate, and hydroxyl group-containing acrylic monomer were changed as follows. .
That is, 25 parts of cyclohexyl acrylate (CHA), 60.8 parts of poly (tetramethylene) glycol (trade name “PTMG-650”) having a number average molecular weight of 650, 0.01 part of dibutyltin dilaurate (DBTL), water 20.9 parts of added xylylene diisocyanate (HXDI) and 3.3 parts of hydroxyethyl acrylate (HEA) were used.

In addition, the usage-amount of a polyisocyanate component and a polyol component is an equivalent ratio, NCO / OH = 1.25, the amount of solid components (for polymerization rate) is 80 mass%, and a solid component (urethane acrylate polymer) The weight average molecular weight (Mw) was 34,000.

Example 1
0.15 of 2,2-dimethoxy-1,2-diphenylethane-1-one (trade name “IRGACURE 651”, manufactured by Ciba Japan KK) as a photopolymerization initiator for 100 parts of syrup I After adding a part, stirring and mixing, this coating liquid was applied on a polyethylene terephthalate (PET) film having a thickness of 100 μm so that the thickness after curing was 100 μm, and a coating layer (lower layer) Was made.

Separately, 1.0 part of hexanediol diacrylate (HDDA) (manufactured by Shin-Nakamura Chemical Co., Ltd.) was added as a crosslinking agent to 100 parts of syrup A, and after stirring and mixing, On the polyethylene terephthalate (PET) film having a thickness of 38 μm, the coated layer (upper layer) was prepared by applying the film so that the thickness after curing was 100 μm.

The prepared two coating layers are bonded together, that is, the upper layer and the lower layer are bonded so that air bubbles do not enter, and irradiated with ultraviolet rays (illuminance 4.0 mW / cm ² , light amount 900 mJ / cm ² ) using a black light. And a multilayer sheet having an active energy ray-curable resin layer on a PET film was produced. The tack of the obtained multilayer sheet was measured. The results are shown in Table 1.

(Examples 2 to 5, Examples 7 to 8, and Comparative Examples 1 to 4)
A multilayer sheet was produced in the same manner as in Example 1 except that the syrup used for producing the coating layer (upper layer) and the coating layer (lower layer) was changed as shown in Tables 1 and 2. The tack of the obtained multilayer sheet was measured. The results are shown in Tables 1 and 2.

(Example 6)
A multilayer sheet was produced in the same manner as in Example 2 except that the thickness of the coating layer (upper layer) and the thickness of the coating layer (lower layer) were changed as shown in Table 1. The tack of the obtained multilayer sheet was measured. The results are shown in Table 1.

As is clear from Table 1 and Table 2, in the multilayer sheets of Examples 1 to 8, a large difference was observed between the surface tack value of the upper layer and the surface tack value of the lower layer, and the upper and lower layers were functionally separated. I found out that On the other hand, in the multilayer sheets of Comparative Example 1 and Comparative Example 3, since the weight average molecular weight (Mw) of the lower layer solid component is smaller than 10,000, the component diffuses into adjacent layers, and the characteristics of each layer are impaired. I understood that. That is, in Comparative Example 1 and Comparative Example 3, for example, the surface tack value of the upper layer is lowered in Comparative Example 1 as compared with Examples 1 to 5 having the same thickness, and Comparative Example 3 is an example having the same thickness. As compared with 7 to 8, the surface tack value of the upper layer was lowered, and it was found that functional separation between the upper layer and the lower layer could not be realized. Further, in Comparative Example 2 and Comparative Example 4 in which the total value of the solid component amounts of the adjacent layers is less than 50% by mass, low molecular weight components that can move between the layers increase. Tack appeared, and it was found that functional separation between the upper layer and the lower layer could not be realized.

Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on a Japanese patent application filed on July 5, 2010 (Japanese Patent Application No. 2010-152686) and a Japanese patent application filed on June 28, 2011 (Japanese Patent Application No. 2011-143322). Is incorporated herein by reference.

Since the multilayer sheet obtained by the production method of the present invention can give each layer a separate function, it can be applied to various applications.

Claims (5)

A method for producing a multilayer sheet obtained by batch polymerization by irradiating active energy rays to at least two active energy ray-curable resin layers,
At least one of the active energy ray-curable resin layers is an active energy ray-curable resin layer A formed by a resin composition A containing an active energy ray-curable acrylic monomer,
At least one of the active energy ray-curable resin layers is an active energy ray-curable resin layer B formed of a resin composition B containing an active energy ray-curable acrylic monomer and a solid component made of a urethane polymer. And
The solid component made of the urethane polymer has a weight average molecular weight of 10,000 or more, and the solid component amount (polymerization ratio) of the solid component made of the urethane polymer in the resin composition B is 35% by mass or more. ,
The total amount of solid components (polymerization ratio) of two active energy ray-curable resin layers adjacent to each other is 50% by mass or more,
A method for producing a multilayer sheet. The method for producing a multilayer sheet according to claim 1, wherein the urethane polymer is an acryloyl group-terminated urethane polymer. The method for producing a multilayer sheet according to claim 1 or 2, wherein the active energy ray-curable resin layer A and the active energy ray-curable resin layer B are adjacent to each other. A multilayer sheet obtained by the method for producing a multilayer sheet according to any one of claims 1 to 3. The multilayer sheet according to claim 4, wherein the layer adjacent to the active energy ray-curable resin layer B is a layer having tack at normal temperature.

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