JP2020059812A - Curing agent, undercoat agent and film - Google Patents

Abstract

To provide a curing agent, an undercoat agent and a film.SOLUTION: There is provided a curing agent that is a reactant of a compound group containing a polyisocyanate adduct, water and a hydroxyl group-containing compound, and contains a modified polyisocyanate adduct having 13 mass% or less of an isocyanate group content of 100 mass% of a solid content. The polyisocyanate adduct is a reactant of hydrogenated xylylene diisocyanate and trimethylolpropane.SELECTED DRAWING: None

Description

  The present disclosure relates to curing agents, undercoat agents and films.

  As a manufacturing method for decorating the surface of plastic products such as patterns and textures and for imparting scratch resistance (hard coat property), an adhesive layer, pattern layer, and hard coat layer are laminated on a plastic film such as PET (polyethylene terephthalate) The in-mold injection molding method is used in which the above-mentioned decorative film is inserted into a mold and is attached to a molded product simultaneously with injection molding.

  The in-mold injection molding method is classified into an injection-mold simultaneous transfer decorative method and an injection-mold simultaneous laminating decorative method, depending on the configuration of the decorative film attached to the resin molded product.

  In the injection molding simultaneous transfer decoration method, a release layer is formed on one surface of a substrate film, and a transfer layer (a layer in which a hard coat layer, a pattern layer, an adhesive layer, and the like are laminated in this order) is laminated on the release layer. Insert the decorative film for transfer into the mold, install it so that the base film side is in close contact with the inner surface of the mold, and after closing the mold, inject the molten thermoplastic resin into the mold from the transfer layer side. After the filling, when the mold is opened and the molded product is taken out, the release layer and the hard coat layer are separated, so that the transfer layer is transferred to the outermost surface to obtain a molded product.

  In many cases, an active energy ray-curable resin is used as the material used for the hard coat layer (Patent Document 1).

JP, 2008-006708, A

  A problem when the hard coat layer is an active energy ray-curable hard coat layer is that the adhesion between the active energy ray-curable hard coat layer and the pattern layer is poor. Therefore, an undercoat layer that provides adhesion is provided between the active energy ray-curable hard coat layer and the pattern layer.

  Here, when an undercoat layer is provided, that is, when an undercoat agent is used, not only adhesion but also imprintability and wet heat resistance may be required to be good. Therefore, the problem to be solved by the present invention is to provide a curing agent capable of producing a film having good initial adhesion, light-resistant adhesion, imprintability, and wet heat resistance.

  As a result of intensive studies, the present inventors have found that the above problems can be solved by a specific curing agent.

The present disclosure provides the following items.
(Item 1)
A curing agent containing a modified polyisocyanate adduct, which is a reaction product of a compound group containing a polyisocyanate adduct, water and a hydroxyl group-containing compound, and has an isocyanate group content of 13 mass% or less at a solid content of 100 mass%.
(Item 2)
The curing agent according to the above item, wherein the polyisocyanate adduct is a reaction product of hydrogenated xylylene diisocyanate and trimethylolpropane.
(Item 3)
An undercoat agent containing the curing agent according to any one of the above items.
(Item 4)
Item 4. The undercoat agent according to Item 3, comprising a urethane (meth) acrylic copolymer which is a reaction product of a hydroxyl group-containing (meth) acrylic copolymer and polyisocyanate.
(Item 5)
A film in which an undercoating agent cured product layer containing the cured product of the undercoating agent according to any one of the above items is laminated on at least one surface of the film.

  In the present disclosure, one or more of the features described above may be provided in addition to the explicit combination.

  By using the curing agent of the present invention, it is possible to obtain a film having good imprintability, initial adhesion, resistance to moist heat and light adhesion.

  Throughout the present disclosure, ranges of numerical values such as physical properties and contents can be set appropriately (for example, by selecting from the upper limit value and the lower limit value described in each item below). Specifically, regarding the numerical value α, the upper limit of the numerical value α is exemplified by A1, A2, A3, etc., and the lower limit of the numerical value α is exemplified by B1, B2, B3, etc., the range of the numerical value α is A1 or less, A2 or less, A3 or less, B1 or more, B2 or more, B3 or more, A1 to B1, A1 to B2, A1 to B3, A2 to B1, A2 to B2, A2 to B3, A3 to B1, A3 to B2, A3 to B3. Etc. are illustrated.

[Curing agent]
The present disclosure relates to a reaction product of a compound group containing a polyisocyanate adduct, water and a hydroxyl group-containing compound, and a curing agent containing a modified polyisocyanate adduct having a solid content of 100 mass% and an isocyanate group content of 13 mass% or less. provide.

<Polyisocyanate adduct>
Examples of the polyisocyanate adduct include reaction products of polyisocyanate and polyol.

(Polyisocyanate)
In the present disclosure, "polyisocyanate" is a compound having two or more isocyanate groups (-N = C = O). The polyisocyanates may be used alone or in combination of two or more.

  Examples of polyisocyanates include aliphatic polyisocyanates, aromatic polyisocyanates, and alicyclic polyisocyanates.

  Examples of the aliphatic polyisocyanate include linear aliphatic polyisocyanate and branched aliphatic polyisocyanate.

Examples of the linear aliphatic group include linear alkylene groups and the like. Linear alkylene groups _{- (CH 2) n - (} n is an integer of 1 or more) can be represented by the general formula, methylene group, ethylene group, propylene group, n- butylene, n- pentylene, n- hexylene , N-heptylene group, n-octylene group, n-nonylene group, n-decamethylene group and the like.

  Linear aliphatic polyisocyanates include methylene diisocyanate, dimethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, octamethylene diisocyanate, nonamethylene diisocyanate, decamethylene diisocyanate, etc. It

  A branched alkylene group etc. are illustrated as a branched aliphatic group. The branched alkylene group is a group in which at least one hydrogen of a linear alkylene group is substituted with an alkyl group, and specific examples thereof include a diethylpentylene group, a trimethylbutylene group, a trimethylpentylene group, a trimethylhexylene group ( Trimethylhexamethylene group) and the like.

  Examples of the branched aliphatic polyisocyanate include diethyl pentylene diisocyanate, trimethyl butylene diisocyanate, trimethyl pentylene diisocyanate and trimethyl hexamethylene diisocyanate.

  Examples of the alicyclic group include a monocyclic alicyclic group, a crosslinked alicyclic group, and a condensed alicyclic group. Further, in the cycloalkylene group, one or more hydrogen may be substituted with a linear or branched alkyl group.

  In the present disclosure, a single ring means a cyclic structure having no internal bridge structure formed by a carbon covalent bond. Further, the fused ring means a cyclic structure in which two or more monocycles share two atoms (that is, only one side of each ring is shared (fused) with each other). A bridged ring means a cyclic structure in which two or more monocycles share three or more atoms.

  Examples of the monocyclic alicyclic group include a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclodecylene group, and a 3,5,5-trimethylcyclohexylene group.

  Examples of the crosslinked alicyclic group include tricyclodecylene group, adamantylene group, norbornylene group and the like.

  Examples of the condensed ring alicyclic group include a bicyclodecylene group and the like.

  Examples of the alicyclic polyisocyanate include monocyclic alicyclic polyisocyanate, crosslinked alicyclic polyisocyanate, and condensed alicyclic polyisocyanate.

  Monocyclic alicyclic polyisocyanates include hydrogenated xylylene diisocyanate, isophorone diisocyanate, cyclopentylene diisocyanate, cyclohexylene diisocyanate, cycloheptylene diisocyanate, cyclodecylylene diisocyanate, 3,5,5-trimethylcyclohexylene diisocyanate, dicyclohexyl. Examples include methane diisocyanate.

  Examples of the crosslinked alicyclic polyisocyanate include tricyclodecylylene diisocyanate, adamantane diisocyanate and norbornene diisocyanate.

  Examples of the condensed ring alicyclic polyisocyanate include bicyclodecylylene diisocyanate.

  The carbon number of the aliphatic group is not particularly limited, but its upper limit is exemplified by 30, 29, 25, 20, 15, 12, 10, 9, 8, 7, 6, 5, 4, 3, 2, etc. The lower limit is exemplified by 29, 25, 20, 15, 12, 10, 9, 8, 7, 7, 6, 5, 4, 3, 2, 1. In one embodiment, 1-30 are preferable, as for carbon number of an aliphatic group, 1-20 are more preferable, 1-16 are more preferable, and 1-12 are especially preferable.

  Examples of the aromatic group include a phenylene group and a naphthylene group.

  Examples of the aromatic polyisocyanate include xylene diisocyanate.

The upper limit of the content of the structural unit derived from polyisocyanate in 100 mass% of polyisocyanate adduct is, for example, 85, 80, 75, 70, 65 mass%, and the lower limit is 80, 75, 70, 65, 60 mass. % Etc. are illustrated. In one embodiment, the content of the structural unit derived from polyisocyanate in 100% by mass of the polyisocyanate adduct is preferably 60 to 85% by mass.

The upper limit of the content of the structural unit derived from polyisocyanate in 100 mol% of polyisocyanate adduct is, for example, 75, 74, 73, 72, 71 mol%, and the lower limit is 74, 73, 72, 71, 70 mol. % Etc. are illustrated. In one embodiment, the content of the structural unit derived from polyisocyanate in 100 mol% of polyisocyanate adduct is preferably 70 to 75 mol%.

(Polyol) Examples of the polyol include (poly) pentaerythritol, (poly) trimethylolpropane, (poly) glycerin, sorbitol, sugar and the like.

((Poly) pentaerythritol)
(Poly) pentaerythritol has the structural formula (1)
(In the formula, m is an integer of 0 or more.)
Is a compound represented by.

  Examples of (poly) pentaerythritol include pentaerythritol, dipentaerythritol, tripentaerythritol, and tetrapentaerythritol.

((Poly) trimethylolpropane)
(Poly) trimethylolpropane has the structural formula (2)
(In the formula, p is an integer of 0 or more.)
Is a compound represented by.

  Examples of the (poly) trimethylolpropane include trimethylolpropane and ditrimethylolpropane.

The upper limit of the content of the polyol-derived constituent unit in 100% by mass of the polyisocyanate adduct is, for example, 40, 35, 30, 25, 20% by mass, and the lower limit is 35, 30, 25, 20, 15% by mass. Etc. are illustrated. In one embodiment, the content of the structural unit derived from the polyol in 100% by mass of the polyisocyanate adduct is preferably 15 to 40% by mass.

The upper limit of the content of the polyol-derived constituent unit in 100 mol% of the polyisocyanate adduct is, for example, 30, 29, 28, 27, 26 mol%, and the lower limit is 29, 28, 27, 26, 25 mol%. Etc. are illustrated. In one embodiment, the content of the constitutional unit derived from the polyol in 100 mol% of the polyisocyanate adduct is preferably 25 to 30 mol%.

The upper limit of the mass ratio of the polyisocyanate-derived constitutional unit and the polyol-derived constitutional unit in the polyisocyanate adduct is 6, 5.5, 4.5, 4, 4, 3.5, 3, 2.5, 2. Etc. are illustrated, and the lower limit is 5.5, 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, etc. In one embodiment, the mass ratio of the constitutional unit derived from polyisocyanate to the constitutional unit derived from polyol in the polyisocyanate adduct is preferably 1.5 to 6.

The upper limit of the molar ratio of the polyisocyanate-derived constitutional unit and the polyol-derived constitutional unit in the polyisocyanate adduct is exemplified by 3, 2.9, 2.7, 2.5, 2.3, 2.1 and the like. , The lower limit is 2.9, 2.7, 2.5, 2.3, 2.1, 2 and the like. In one embodiment, the molar ratio of the constitutional unit derived from polyisocyanate to the constitutional unit derived from polyol in the polyisocyanate adduct is preferably 2 to 3.

  In one embodiment, the polyisocyanate adduct is a reaction product of hydrogenated xylylene diisocyanate and trimethylolpropane.

Polyisocyanate adduct is
The following structural formula:
[In the formula, R ^{1A to} R ^1E are each independently an aliphatic group or an aromatic group, and R ^{A to} R ^B are each independently an isocyanate group, or
(R ^{a and} R ^b are each independently an aliphatic group or an aromatic group for each structural unit, R is an isocyanate group or ^RA group itself, and n is an integer of 1 or more.)
And
R ^1D , R ^1E , and R ^B may have different groups for each structural unit. n1 is an integer of 0 or more. n1 is preferably 0-2. ]
The reaction product of trimethylolpropane and polyisocyanate represented by

Examples of commercially available polyisocyanate adducts include Duranate P301-75E (all manufactured by Asahi Kasei Co., Ltd.) and Takenate D120N (all manufactured by Mitsui Chemicals, Inc.).

  The upper limit of the weight average molecular weight (Mw) of the polyisocyanate adduct is, for example, 3000, 2900, 2500, 2000, 1900, 1500, 1000, 900, and the lower limit is 2900, 2500, 2000, 1900, 1500, 1000, 900. , 800, etc. are exemplified. In one embodiment, the weight average molecular weight (Mw) of the polyisocyanate adduct is preferably 800 to 3000.

  The upper limit of the number average molecular weight (Mn) of the polyisocyanate adduct is, for example, 2500, 2400, 2000, 1900, 1500, 1000, 900, and the lower limit is 2400, 2000, 1900, 1500, 1000, 900, 800, etc. It is illustrated. In one embodiment, the number average molecular weight (Mn) of the polyisocyanate adduct is preferably 700 to 2500.

  The upper limit of the molecular weight distribution (Mw / Mn) of the polyisocyanate adduct is 5, 4, 3, 2, etc., and the lower limit is 4, 3, 2, 1, etc. In one embodiment, the polyisocyanate adduct preferably has a molecular weight distribution (Mw / Mn) of 1 to 5.

  The weight average molecular weight (Mw) and the number average molecular weight (Mn) can be obtained as polystyrene conversion values measured by gel permeation chromatography (GPC) (the same applies hereinafter).

  The upper limit of the proportion of polyisocyanate adduct in 100% by mass of the compound group is, for example, 95, 94, 93, 92, 91% by mass, and the lower limit is 94, 93, 92, 91, 90% by mass, etc. To be done. In one embodiment, the proportion of the polyisocyanate adduct in 100% by mass of the above compound group is preferably 90 to 95% by mass.

  The upper limit of the proportion of polyisocyanate adduct in 100 mol% of the compound group is, for example, 70, 65, 60, 55 mol% and the like, and the lower limit is, for example, 65, 60, 55, 50 mol% and the like. In one embodiment, the proportion of the polyisocyanate adduct in 100 mol% of the above compound group is preferably 50 to 70 mol%.

<Hydroxyl-containing compound>
Examples of the hydroxyl group-containing compound include alcohol and hydroxyl group-containing alkyl (meth) acrylate.

  Examples of alcohol include monoalcohol and polyol.

  Examples of the polyol include those mentioned above.

  Examples of the hydroxyl group-containing alkyl (meth) acrylate include those described below.

  The upper limit of the hydroxyl value of the hydroxyl group-containing compound is, for example, 1260, 1200, 1000, 900, 750, 500, 400 mgKOH / g, and the lower limit is 1200, 1000, 900, 750, 500, 400, 380 mgKOH / g, etc. It is illustrated. In one embodiment, the hydroxyl value of the hydroxyl group-containing compound is preferably 380 to 1260 mgKOH / g.

In the present disclosure, the hydroxyl value is the following formula (hydroxyl value) = (potassium hydroxide molecular weight: 56.1) × 1000 / (hydroxyl equivalent)
(Hydroxyl equivalent) = (molecular weight of one molecule) / (number of hydroxyl groups present in one molecule)
It is a calculated value by.

  The upper limit of the ratio of the hydroxyl group-containing compound in 100% by mass of the above compound group is exemplified by 10, 9, 7, 5, 4, 2 and 2% by mass, and the lower limit is 9, 7, 5, 4, 2, 1% by mass. % Etc. are illustrated. In one embodiment, the ratio of the hydroxyl group-containing compound in 100% by mass of the compound group is preferably 1 to 10% by mass.

  The upper limit of the proportion of the hydroxyl group-containing compound in 100 mol% of the above compound group is, for example, 40, 35, 30, 25, 20, 15, 10 mol%, and the lower limit is 35, 30, 25, 20, 15, For example, 10, 5 mol% and the like are exemplified. In one embodiment, the ratio of the hydroxyl group-containing compound in 100 mol% of the above compound group is preferably 5 to 40 mol%.

  The upper limit of the proportion of water in the compound group 100 mass% is exemplified by 1, 0.9, 0.7, 0.5, 0.3 mass% and the like, and the lower limit is 0.9, 0.7, 0.5, 0.3, 0.2 mass% etc. are illustrated. In one embodiment, the proportion of water in the compound group of 100% by mass is preferably 0.2 to 1% by mass.

  The upper limit of the proportion of water in 100 mol% of the compound group is, for example, 30, 25, 20, 15 mol%, and the lower limit is, for example, 25, 20, 15, 10 mol%. In one embodiment, the proportion of water in 100 mol% of the compound group is preferably 10 to 30 mol%.

<Compound that is neither a polyisocyanate adduct, water nor a hydroxyl group-containing compound: Also referred to as other compound>
The compound group may include a compound that is neither a polyisocyanate adduct, water nor a hydroxyl group-containing compound.

  Examples of other compounds include monoisocyanate, polyisocyanurate, polyisocyanate biuret, and polyisocyanate allophanate.

  In one embodiment, the ratio of the other compound to 100% by mass of the compound group is less than 5 parts by mass, less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, 0 part by mass and the like. To be done.

  In one embodiment, the ratio of the other compound to 100 mol% of the compound group is less than 5 mol%, less than 1 mol%, less than 0.1 mol%, less than 0.01 mol%, 0 mol%, etc. To be done.

<Modified polyisocyanate adduct>
The upper limit of the isocyanate group content of the modified polyisocyanate adduct at a solid content of 100 mass% is exemplified by 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 mass% and the like. The lower limit is, for example, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 mass%. In one embodiment, the modified polyisocyanate adduct preferably has an isocyanate group content of 13% by mass or less when the solid content is 100% by mass.

The isocyanate group content of the modified polyisocyanate adduct can be measured by the following method using, for example, an automatic potentiometric titrator (manufactured by Kyoto Electronics Manufacturing Co., Ltd.).
1) Collect 0.5 g of the sample in a 200 mL Erlenmeyer flask.
2) Add 20 mL of dehydrated toluene to dissolve the sample.
3) Add 10.0 mL of 0.2 mol / L di-n-butylamine solution.
4) Shake to homogenize and leave for 20 minutes or more.
5) Add 100 mL of isopropyl alcohol.
6) Titrate with 0.1 mol / L hydrochloric acid solution.
7) A blank test is conducted by the same operation, and the isocyanate group content is calculated using the following formula.
Isocyanate group content = (SIZE / ((BL1-EP1) × FA1)) × K2
EP1: Titration amount (mL)
BL1: Blank value FA1: Factor of titrant (1.00)
K2: Coefficient (1000)
SIZE: sampling amount (g)
The isocyanate group content of 100% solids is twice the isocyanate group content of 50% solids.

  The upper limit of the proportion of the group reacting with water and / or a hydroxyl group-containing compound in the isocyanate group of the polyisocyanate adduct is exemplified by 30, 29, 27, 25, 23, 21, 20, 19, 17 mol% and the like. The lower limit is, for example, 29, 27, 25, 23, 21, 20, 19, 17, 15 mol% or the like. In one embodiment, 15 mol% or more is preferable and, as for the ratio of the group reacting with water and / or a hydroxyl group-containing compound among the isocyanate groups which a polyisocyanate adduct has, 20-30 mol% is more preferable.

  The upper limit of the weight average molecular weight (Mw) of the polyisocyanate adduct is 6000, 5000, 4000, 3000, 2000, 1500, 1300, etc., and the lower limit is 5000, 4000, 3000, 2000, 1500, 1300, 1200, etc. It is illustrated. In one embodiment, the weight average molecular weight (Mw) of the polyisocyanate adduct is preferably 1200 to 6000.

  The upper limit of the number average molecular weight (Mn) of the polyisocyanate adduct is, for example, 5000, 4000, 3000, 2000, 1500, and the lower limit is, for example, 4000, 3000, 2000, 1500, 1000. In one embodiment, the number average molecular weight (Mn) of the polyisocyanate adduct is preferably 1000 to 5000.

  The upper limit of the molecular weight distribution (Mw / Mn) of the polyisocyanate adduct is 6, 5, 4, 3, 2, etc., and the lower limit is 5, 4, 3, 2, 1, etc. In one embodiment, the polyisocyanate adduct preferably has a molecular weight distribution (Mw / Mn) of 1 to 6.

  The method for producing the modified polyisocyanate adduct may be a known method, such as polyisocyanate, water and a hydroxyl group-containing compound and optionally other compounds, without solvent or in a suitable solvent (toluene or the like), The reaction may be performed at an appropriate reaction temperature (60 to 90 ° C. or the like) in the presence of an appropriate catalyst (tin octylate or the like).

<Additives>
The curing agent may include agents other than the modified polyisocyanate adduct as an additive. Examples of the additive include a polymerization inhibitor, an antioxidant, a light stabilizer, a defoaming agent, a surface modifier, a pigment, an antistatic agent, a metal oxide fine particle dispersion, an organic fine particle dispersion and the like. In one embodiment, the content of the additive is about 0.1 to 10% by mass of the curing agent, about 10 parts by mass, about 5 parts by mass, about 1 part by mass, about 0.1 part by mass. The amount is, for example, less than 0.01 parts by mass, about 0 parts by mass, and the like.

  The above curing agent can be used as a curing agent for an undercoat agent, a curing agent for a transfer foil, a curing agent for a transfer foil in an in-mold injection molding method, and the like.

[Undercoat agent]
The present disclosure provides an undercoat agent including the above-mentioned curing agent.

  In one embodiment, the undercoat agent includes a urethane (meth) acrylic copolymer that is a reaction product of a hydroxyl group-containing (meth) acrylic copolymer and polyisocyanate.

<Hydroxyl group-containing (meth) acrylic copolymer>
Examples of the hydroxyl group-containing (meth) acrylic copolymer include copolymers containing a structural unit derived from a non-hydroxylated alkyl (meth) acrylate and a structural unit derived from a hydroxyl group-containing alkyl (meth) acrylate. In producing the urethane (meth) acrylic copolymer, one or more hydroxyl group-containing (meth) acrylic copolymers may be used.

(Hydroxyl-free alkyl (meth) acrylate)
Hydroxyl-free alkyl (meth) acrylate is
(In the formula, R ^a1 is a hydrogen atom or a methyl group, and R ^a2 is an alkyl group.)
Is represented by The hydroxyl group-free alkyl (meth) acrylate may be used alone or in combination of two or more.

  Examples of the alkyl group include a linear alkyl group, a branched alkyl group, a cycloalkyl group and the like.

Straight chain alkyl _{group, -C n H 2n + 1 (} n is an integer of 1 or more) represented by the general formula. The linear alkyl group includes a methyl group, an ethyl group, a propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decamethyl group, etc. Is exemplified.

  A branched alkyl group is a group in which at least one hydrogen of a straight chain alkyl group is replaced with an alkyl group. Examples of the branched alkyl group include a diethylpentyl group, trimethylbutyl group, trimethylpentyl group, trimethylhexyl group and the like.

  Examples of the cycloalkyl group include a monocyclic cycloalkyl group, a bridged ring cycloalkyl group, and a condensed ring cycloalkyl group.

  Examples of the monocyclic cycloalkyl group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclodecyl group, and a 3,5,5-trimethylcyclohexyl group.

  Examples of the bridged ring cycloalkyl group include a tricyclodecyl group, an adamantyl group and a norbornyl group.

  Examples of the condensed ring cycloalkyl group include a bicyclodecyl group and the like.

  Examples of the hydroxyl group-free alkyl (meth) acrylate include hydroxyl group-free linear alkyl (meth) acrylate, hydroxyl group-free branched alkyl (meth) acrylate, and hydroxyl group-free cycloalkyl (meth) acrylate.

  Non-hydroxyl group-containing linear alkyl (meth) acrylates include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, and hexyl (meth) acrylate. , Heptyl (meth) acrylate, octyl (meth) acrylate, hexadecyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate, icosyl (meth) acrylate, docosyl (meth) acrylate, etc. Is exemplified.

  Hydroxyl-free branched alkyl (meth) acrylates include isopropyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, 2- (meth) acrylate. Ethylhexyl etc. are illustrated.

  Examples of the hydroxyl group-free cycloalkyl (meth) acrylate include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclopentanyl (meth) acrylate, and isobornyl (meth) acrylate.

  Among these, an alkyl (meth) acrylate having an alkyl group with about 1 to 20 carbon atoms is preferable because it contributes to the leveling property and the adhesiveness in the undercoat agent. Further, by using together a hydroxyl group-free alkyl (meth) acrylate in which the number of carbon atoms of the alkyl group is different, the physical properties such as the glass transition temperature of the hydroxyl group-containing (meth) acrylic copolymer can be adjusted.

  The upper limit of the content of the structural unit derived from the non-hydroxyl-containing alkyl (meth) acrylate in 100 mol% of all the structural units of the hydroxyl-containing (meth) acrylic copolymer is 98, 95, 90, 85, 80, 75, 70, 65. Mol% and the like are exemplified, and the lower limit is 95, 90, 85, 80, 75, 70, 65, 62 mol% and the like. In one embodiment, the range of the content of the structural unit derived from the non-hydroxyl-containing alkyl (meth) acrylate in 100 mol% of all the structural units of the hydroxyl-containing (meth) acrylic copolymer is preferably about 62 to 98 mol%.

  The upper limit of the content of the structural unit derived from the non-hydroxyl-containing alkyl (meth) acrylate in 100% by mass of all the structural units of the hydroxyl group-containing (meth) acrylic copolymer is 98, 95, 90, 85, 80, 75, 70% by mass. And the like, and the lower limit is, for example, 95, 90, 85, 80, 75, 70, 65% by mass. In one embodiment, the range of the content of the structural unit derived from the non-hydroxyl-containing alkyl (meth) acrylate in 100% by mass of all the structural units of the hydroxyl-containing (meth) acrylic copolymer is preferably about 65 to 98% by mass.

(Hydroxyl group-containing alkyl (meth) acrylate)
The hydroxyl group-containing alkyl (meth) acrylate has the following structural formula
(In the formula, R ^a3 is a hydrogen atom or a methyl group, and R ^a4 is a linear alkylene group, a branched alkylene group, or a cycloalkylene group.)
Is represented by Two or more kinds of the hydroxyl group-containing alkyl (meth) acrylate may be used in combination.

  Examples of the hydroxyl group-containing alkyl (meth) acrylate include hydroxyl group-containing linear alkyl (meth) acrylate, hydroxyl group-containing branched alkyl (meth) acrylate, and hydroxyl group-containing cycloalkyl (meth) acrylate.

  Examples of the hydroxyl group-containing linear alkyl (meth) acrylate include hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate.

  Examples of the hydroxyl group-containing branched alkyl (meth) acrylate include 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 3-hydroxybutyl (meth) acrylate.

  Examples of the hydroxyl group-containing cycloalkyl (meth) acrylate include hydroxycyclohexyl (meth) acrylate and 4- (hydroxymethyl) cyclohexylmethyl (meth) acrylate.

  The hydroxyl group-containing alkyl (meth) acrylate preferably has a hydroxyalkyl group having about 1 to 4 carbon atoms from the viewpoint of the pot life of the undercoat agent and the like.

  The upper limit of the content of the structural unit derived from the hydroxyl group-containing alkyl (meth) acrylate in 100 mol% of all the structural units of the hydroxyl group-containing (meth) acrylic copolymer is 20, 18, 15, 10, 5, 2.5 mol%, etc. And the lower limit is 18, 15, 10, 5, 2.5, 1.5 mol% and the like. In one embodiment, the range of the content of the constituent unit derived from the hydroxyl group-containing alkyl (meth) acrylate in 100 mole% of all the constituent units of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 1.5 to 20 mole%.

  The upper limit of the content of the structural unit derived from the hydroxyl group-containing alkyl (meth) acrylate in 100% by mass of all the structural units of the hydroxyl group-containing (meth) acrylic copolymer is, for example, 15, 14, 10, 5, 2.5% by mass. The lower limit is, for example, 13, 10, 5, 2.5, 2 mass% and the like. In one embodiment, the range of the content of the structural unit derived from the hydroxyl group-containing alkyl (meth) acrylate in 100% by mass of all the structural units of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 2 to 15% by mass.

A substance ratio of a structural unit derived from a non-hydroxyl-containing alkyl (meth) acrylate and a structural unit derived from a non-hydroxyl-containing alkyl (meth) acrylate in a hydroxyl-containing (meth) acrylic copolymer (hydroxyl-free alkyl (meth) acrylate _mol / hydroxyl group) The upper limit of the content of alkyl (meth) acrylate ( _mol ) is, for example, 65, 60, 50, 40, 30, 20, 10, 6 and the like, and the lower limit is 60, 55, 50, 40, 30, 20, 10, 5. .5 etc. are illustrated. In one embodiment, the substance amount ratio of the constitutional unit derived from the non-hydroxyl-containing alkyl (meth) acrylate and the constitutional unit derived from the non-hydroxyl-containing alkyl (meth) acrylate in the hydroxy-containing (meth) acrylic copolymer (the non-hydroxyl-containing alkyl ( The (meth) acrylate _mol / hydroxyl group-containing alkyl (meth) acrylate _mol ) is preferably about 5.5 to 65.

Mass ratio of structural unit derived from non-hydroxyl-containing alkyl (meth) acrylate and structural unit derived from non-hydroxyl-containing alkyl (meth) acrylate in hydroxyl-containing (meth) acrylic copolymer (hydroxyl-free alkyl (meth) acrylate _mass / hydroxyl-containing The upper limit of the alkyl (meth) acrylate _mass is 50, 45, 40, 30, 20, 10, 7, etc., and the lower limit is 48, 45, 40, 30, 20, 10, 6, etc. . In one embodiment, the mass ratio of the constitutional unit derived from the non-hydroxyl-containing alkyl (meth) acrylate and the constitutional unit derived from the non-hydroxylated alkyl (meth) acrylate in the hydroxy-containing (meth) acrylic copolymer (the non-hydroxyl-containing alkyl (meth ) Acrylate _mass / hydroxyl group-containing alkyl (meth) acrylate _mass is preferably about 6 to 50.

(Monomers other than hydroxyl group-free alkyl (meth) acrylate and hydroxyl group-containing alkyl (meth) acrylate: Also referred to as other monomers)
When producing a hydroxyl group-containing (meth) acrylic copolymer, a monomer that does not correspond to neither a hydroxyl group-containing alkyl (meth) acrylate nor a hydroxyl group-containing alkyl (meth) acrylate may be used. Two or more other monomers may be used in combination.

  Other monomers include (meth) acrylic acid, α, β-unsaturated carboxylic acid, epoxy group-containing (meth) acrylate, styrenes, α-olefins, unsaturated alcohols, aryl (meth) acrylates, dialkylaminoalkyl (meth) acrylates. ) Acrylate and salts thereof, dialkylaminoalkyl (meth) acrylamide and salts thereof, chain transfer monomer, (meth) acrylonitrile, (meth) acrylamides, vinylamine, monofunctional monomers other than the above, bis (meth) acrylamide , Di (meth) acrylic ester, divinyl ester, bifunctional monomers other than the above, trifunctional monomers, tetrafunctional monomers and the like.

  The upper limit of the content of the structural units derived from other monomers in 100 mol% of all the structural units of the hydroxyl group-containing (meth) acrylic copolymer is exemplified by 20, 15, 10, 9, 5, 4, 1 mol% and the like. The lower limit is exemplified by 18, 15, 10, 9, 5, 5, 4, 1, 0 mol% and the like. In one embodiment, the range of the content of the structural unit derived from the other monomer in 100 mol% of all the structural units of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 0 to 20 mol%.

  The upper limit of the content of structural units derived from other monomers in 100% by mass of all structural units of the hydroxyl group-containing (meth) acrylic copolymer is 20, 15, 10, 9, 5, 4, 1% by mass, and the like. The lower limit is, for example, 18, 15, 10, 5, 4, 4, 1, 0 mass%. In one embodiment, the range of the content of the constituent units derived from other monomers in 100% by mass of all the constituent units of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 0 to 20% by mass.

Hydroxyl group-containing (meth) not containing hydroxyl groups alkyl in the acrylic copolymer (meth) substance amount ratio of the structural units and other monomer-derived constituent units derived from acrylate (another monomer _{mol /} not containing hydroxyl groups alkyl (meth) acrylate _mol) The upper limit is 0.30, 0.25, 0.20, 0.15, 0.10, 0.05, etc., and the lower limit is 0.25, 0.20, 0.15, 0.10. , 0.05, 0, etc. are exemplified. In one embodiment, the substance ratio of the structural unit derived from a non-hydroxyl-containing alkyl (meth) acrylate in the hydroxyl-containing (meth) acrylic copolymer and the structural unit derived from another monomer ( _{mol of} other monomer / non-hydroxyl-containing alkyl). The (meth) acrylate _mol ) is preferably about 0 to 0.30.

Of the mass ratio of the structural unit derived from the non-hydroxyl-containing alkyl (meth) acrylate and the structural unit derived from the other monomer in the hydroxyl-containing (meth) acrylic copolymer (other monomer _mass / non-hydroxyl-containing alkyl (meth) acrylate _mass ) The upper limit is, for example, 0.30, 0.25, 0.20, 0.15, 0.10, 0.05, etc., and the lower limit is 0.25, 0.20, 0.15, 0.10, 0.05, 0, etc. are illustrated. In one embodiment, a mass ratio of a structural unit derived from a non-hydroxyl-containing alkyl (meth) acrylate in a hydroxyl-containing (meth) acrylic copolymer to a structural unit derived from another monomer (other monomer _mass / non-hydroxyl-containing alkyl ( The (meth) acrylate _mass ) is preferably about 0 to 0.30.

Upper limit of the substance amount ratio (other monomer _mol / hydroxyl group-containing alkyl (meth) acrylate _mol ) of the hydroxyl-containing alkyl (meth) acrylate-derived structural unit and the other monomer-derived structural unit in the hydroxyl-containing (meth) acrylic copolymer Is 15.0, 10.0, 8.0, 7.0, 6.0, 5.0, 4.0, 3.0, 2.0, 1.0, 0.5, 0.1, etc. And the lower limit is 13.0, 10.0, 8.0, 7.0, 6.0, 5.0, 4.0, 3.0, 2.0, 1.0, 0.5. , 0.1, 0, etc. are exemplified. In one embodiment, the substance amount ratio of the structural unit derived from the hydroxyl group-containing alkyl (meth) acrylate to the structural unit derived from the other monomer in the hydroxyl group-containing (meth) acrylic copolymer (other monomer _mol / hydroxyl group-containing alkyl (meth The acrylate _mol ) is preferably about 0 to 15.0.

The upper limit of the mass ratio (other monomer _mass / hydroxyl group-containing alkyl (meth) acrylate _mass ) of the hydroxyl group-containing alkyl (meth) acrylate-derived structural unit and the other monomer-derived structural unit in the hydroxyl group-containing (meth) acrylic copolymer is , 10.0, 8.0, 5.0, 4.0, 3.0, 2.0, 1.0, 0.5, 0.1, etc., and the lower limit is 8.0, 5. 0, 4.0, 3.0, 2.0, 1.0, 0.5, 0 and the like are exemplified. In one embodiment, the mass ratio of the structural unit derived from a hydroxyl group-containing alkyl (meth) acrylate to the structural unit derived from another monomer in the hydroxyl group-containing (meth) acrylic copolymer (other monomer _mass / hydroxyl group-containing alkyl (meth)) The acrylate _mass ) is preferably about 0 to 10.0.

<Physical properties of hydroxyl group-containing (meth) acrylic copolymer>
The upper limit of the glass transition temperature of the hydroxyl group-containing (meth) acrylic copolymer is, for example, 100, 90, 80, 70, 60, 50, 40, 35 ° C., and the lower limit is 95, 90, 80, 70, 60, 50. , 40, 35, 30, 20 ° C. and the like. In one embodiment, the glass transition temperature of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 20 to 100 ° C, more preferably about 30 to 80 ° C.

  The glass transition temperature is measured using a commercially available measuring instrument (for example, product name "DSC8230B", manufactured by Rigaku Denki Co., Ltd.).

  The upper limit of the hydroxyl equivalent of the hydroxyl group-containing (meth) acrylic copolymer is 1.1, 1.0, 0.5, 0.25, 0.20, 0.17, 0.15, 0.10 meq / g, etc. The lower limit is, for example, 1.0, 0.5, 0.25, 0.20, 0.17, 0.15, 0.10, 0.09 meq / g. In one embodiment, the hydroxyl group equivalent of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 0.09 to 1.1 meq / g, more preferably about 0.17 to 1.1 meq / g, and 0.25 to 0. About 9 meq / g is more preferable.

  In the present disclosure, the hydroxyl group equivalent is the amount of hydroxyl group substance present in 1 g of solid.

  The upper limit of the hydroxyl value (solid content conversion) of the hydroxyl group-containing (meth) acrylic copolymer is, for example, 60, 50, 40, 30, 20, 15 mgKOH / g, and the lower limit is 50, 40, 30, 20, 15, 10 mgKOH / g etc. are illustrated. In one embodiment, the hydroxyl group value (solid content conversion) of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 10 to 60 mgKOH / g.

  The hydroxyl value is measured by the method according to JIS K1557-1.

  The upper limit of the acid value of the hydroxyl group-containing (meth) acrylic copolymer is, for example, 0.4, 0.3, 0.2, 0.18, 0.1, 0.09, 0.05 meq / g, and the lower limit is , 0.35, 0.3, 0.2, 0.18, 0.1, 0.09, 0.05, 0.04 meq / g and the like. In one embodiment, the acid value of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 0.04 to 0.4 meq / g, more preferably about 0.09 to 0.18 meq / g, particularly in consideration of curability. preferable.

  The acid value is measured by the method according to JIS K0070.

  The upper limit of the weight average molecular weight (Mw) of the hydroxyl group-containing (meth) acrylic copolymer is 100,000, 90,000, 80,000, 70,000, 60,000, 50,000, 40,000, 30,000, 20,000, 10,000, 5,000, 4,000, and the like, and the lower limit is 90,000. , 80,000, 70,000, 60,000, 50,000, 40,000, 30,000, 20,000, 10,000, 5,000, 4,000, 3,000 and the like. In one embodiment, the weight average molecular weight (Mw) of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 3,000 to 100,000 from the viewpoints of blocking resistance of the undercoat agent, initial adhesion, and wet heat resistance. About 10,000 to 80,000 is more preferable.

  The upper limit of the number average molecular weight (Mn) of the hydroxyl group-containing (meth) acrylic copolymer is 100,000, 90,000, 80,000, 70,000, 60,000, 50,000, 40,000, 30,000, 20,000, 10,000, 5,000, 4,000, and the like, and the lower limit is 90,000. , 80,000, 70,000, 60,000, 50,000, 40,000, 30,000, 20,000, 10,000, 5,000, 4,000, 3,000 and the like. In one embodiment, the number average molecular weight (Mn) of the hydroxyl group-containing (meth) acrylic copolymer is preferably about 3,000 to 100,000 from the viewpoint of blocking resistance of the undercoat agent, initial adhesion, and wet heat resistance. About 10,000 to 80,000 is more preferable.

  The upper limit of the molecular weight distribution (Mw / Mn) of the hydroxyl group-containing (meth) acrylic copolymer is, for example, 10, 7.5, 5, 2.5, 2, etc., and the lower limit is 9.5, 7.5, 5, 2.5, 2, 1.5, etc. are illustrated. In one embodiment, the hydroxyl group-containing (meth) acrylic copolymer preferably has a molecular weight distribution (Mw / Mn) of about 1.5 to 10.

  The hydroxyl group-containing (meth) acrylic copolymer can be produced by various known methods. The method for producing a hydroxyl group-containing (meth) acrylic copolymer is a method in which a hydroxyl group-free alkyl (meth) acrylate and a hydroxyl group-containing alkyl (meth) acrylate and, if necessary, other monomers are added without solvent or in an organic solvent. Examples include a method of carrying out a copolymerization reaction in the presence of a polymerization initiator at about 80 to 180 ° C. for about 1 to 10 hours. Examples of the organic solvent and the polymerization initiator used in producing the hydroxyl group-containing (meth) acrylic copolymer include those described below.

  Examples of the polyisocyanate used for producing the urethane (meth) acrylic copolymer include those mentioned above.

<Urethane (meth) acrylic copolymer>
The upper limit of the content of the structural unit derived from the hydroxyl group-containing (meth) acrylic copolymer contained in the urethane (meth) acrylic copolymer is, for example, 99.8, 99.5, 99.3, 99.1% by mass, and the lower limit. Are exemplified by 99.5, 99.3, 99.1, 99.0 mass% and the like. In one embodiment, the content of the hydroxyl group-containing (meth) acrylic copolymer-derived constituent unit contained in the urethane (meth) acrylic copolymer is preferably 99.0 to 99.8% by mass of the urethane (meth) acrylic copolymer.

  The upper limit of the content of the structural unit derived from polyisocyanate contained in the urethane (meth) acrylic copolymer is, for example, 1.0, 0.9, 0.7, 0.5, 0.3% by mass, and the lower limit is , 0.9, 0.7, 0.5, 0.3, 0.2 mass% and the like. In one embodiment, the content of the constitutional unit derived from polyisocyanate contained in the urethane (meth) acrylic copolymer is preferably 0.2 to 1.0% by mass of the urethane (meth) acrylic copolymer.

  The upper limit of the mass ratio of the structural unit derived from the hydroxyl group-containing (meth) acrylic copolymer and the structural unit derived from the polyisocyanate contained in the urethane (meth) acrylic copolymer is 500, 450, 400, 350, 300, 250, 200, 150. , 100, etc., and the lower limit is 450, 400, 350, 300, 250, 200, 150, 100, 99, etc. In one embodiment, the mass ratio of the structural unit derived from the hydroxyl group-containing (meth) acrylic copolymer and the structural unit derived from polyisocyanate contained in the urethane (meth) acrylic copolymer is preferably 99 to 500.

  The upper limit of the ratio (NCO / OH) of the isocyanate group equivalent of the polyisocyanate to the hydroxyl group equivalent of the hydroxyl group-containing poly (meth) acrylic polymer at the time of producing the urethane (meth) acrylic copolymer is 0.14, 0.12, 0. .10, 0.09, 0.07, 0.05, etc., and the lower limit is exemplified by 0.12, 0.10, 0.09, 0.07, 0.05, 0.03, etc. . In one embodiment, the ratio (NCO / OH) of the isocyanate group equivalent of the polyisocyanate to the hydroxyl group equivalent of the hydroxyl group-containing poly (meth) acrylic polymer during the production of the urethane (meth) acrylic copolymer is 0.03 to 0. .14 is preferable.

  The upper limit of the weight average molecular weight (Mw) of the urethane (meth) acrylic copolymer is, for example, 200,000, 190000, 175,000, 150000, 125,000, 100000, 90000, 75000, 50000, 25000, 15000, and the lower limit is 190000, 175000, Examples are 150,000, 125,000, 100,000, 90,000, 75,000, 50,000, 25,000, 15,000, 10,000 and the like. In one embodiment, the weight average molecular weight (Mw) of the urethane (meth) acrylic copolymer is preferably 10,000 to 200,000.

  The upper limit of the number average molecular weight (Mn) of the urethane (meth) acrylic copolymer is, for example, 150,000, 125,000, 100,000, 75,000, 50000, 25,000, 10000, 9000, 7500, 6000, and the lower limit is 125,000, 100000, 75,000, Examples are 50000, 25000, 10000, 9000, 7500, 6000 and 5000. In one embodiment, the urethane (meth) acrylic copolymer preferably has a number average molecular weight (Mn) of 5,000 to 150,000.

  The upper limit of the molecular weight distribution (Mw / Mn) of the urethane (meth) acrylic copolymer is 10, 9, 7, 5, 3, etc., and the lower limit is 9, 7, 5, 3, 2, etc. In one embodiment, the urethane (meth) acrylic copolymer preferably has a molecular weight distribution (Mw / Mn) of 2 to 10.

  As a method for producing the urethane (meth) acrylic copolymer, a known method may be adopted, and the hydroxyl group-containing (meth) acrylic copolymer and the polyisocyanate may be appropriately used in a solvent-free or a suitable solvent (toluene or the like) as necessary. The reaction may be performed at an appropriate reaction temperature (60 to 90 ° C. or the like) in the presence of another catalyst (tin octylate or the like).

<Curing catalyst>
The undercoat agent may include a curing catalyst. The curing catalyst may be contained alone or in combination of two or more.

  Examples of the curing catalyst include organic metal catalysts and organic amine catalysts.

  Examples of the organic metal catalyst include organic typical metal catalysts and organic transition metal catalysts.

  Examples of organic typical metal catalysts include organic tin catalysts and organic bismuth catalysts.

  Examples of the organic tin catalyst include dibutyl tin dilaurate and dioctyl tin dilaurate.

  Examples of the organic bismuth catalyst include bismuth octylate.

  Examples of the organic transition metal catalyst include organic titanium catalysts, organic zirconium catalysts, organic iron catalysts and the like.

  Examples of the organic titanium catalyst include titanium ethyl acetoacetate.

  Examples of the organic zirconium catalyst include zirconium tetraacetylacetonate.

  Examples of the organic iron catalyst include iron acetylacetonate.

  Examples of organic amine catalysts include diazabicyclooctane, dimethylcyclohexylamine, tetramethylpropylenediamine, ethylmorpholine, dimethylethanolamine, triethylamine and triethylenediamine.

  When the undercoating agent contains a curing catalyst, the upper limit of the content of the curing catalyst in the undercoating agent is 1, 0.9, 0.75, 0.5, 0.25, 0.1, 0.09. , 0.05, 0.02 mass% and the like, and the lower limit is 0.9, 0.75, 0.5, 0.25, 0.1, 0.09, 0.05, 0.02, 0.01 mass% etc. are illustrated. In one embodiment, when the undercoating agent contains a curing catalyst, the content of the curing catalyst in the undercoating agent is preferably about 0.01 to 1% by mass.

<Organic solvent>
The undercoat agent may include an organic solvent. The organic solvent may be used alone or in combination of two or more. Organic solvents include ketone solvents such as methyl ethyl ketone, acetylacetone, methyl isobutyl ketone and cyclohexanone; aromatic solvents such as toluene and xylene; alcohol solvents such as methanol, ethanol, n-propanol, isopropanol and butanol; ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, Glycol ether solvents such as triethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether and propylene glycol monomethyl ether acetate; ester solvents such as ethyl acetate, butyl acetate, methyl cellosolve acetate and cellosolve acetate; Solvesso # 100 and Solvesso # 150 ( All are trade names. . Haloalkanes solvent such as chloroform; Ltd.) petroleum solvents such as amide solvent such as dimethylformamide and the like. Two or more kinds of organic solvents may be used in combination.

  When the undercoating agent contains an organic solvent, the upper limit of the content of the organic solvent in the undercoating agent is, for example, 90, 80, 70, 60, 50, 40, 30, 20 mass%, and the lower limit is 85, 80, 70, 60, 50, 40, 30, 20, 15 mass% and the like are exemplified. In one embodiment, when the undercoating agent contains an organic solvent, the content of the organic solvent in the undercoating agent is preferably about 15 to 90% by mass, more preferably about 50 to 90% by mass. The organic solvent contained in the undercoat agent may contain the organic solvent contained in the curing agent, the urethane (meth) acrylic copolymer, and the curing catalyst.

<Additives>
The undercoat agent may include an agent other than the curing agent, the urethane (meth) acrylic copolymer, the curing catalyst, and the organic solvent as an additive. Examples of the additive include a polymerization inhibitor, an antioxidant, a light stabilizer, a defoaming agent, a surface modifier, a pigment, an antistatic agent, a metal oxide fine particle dispersion, an organic fine particle dispersion and the like. In one embodiment, as an example of the content of the additive, about 0.1 to 10% by mass of the undercoat agent, about 10 parts by mass or less, about 5 parts by mass or less, about 1 part by mass or less, 0.1 Examples thereof include less than about 1 part by mass, about less than 0.01 part by mass, and about 0 part by mass.

  The undercoat agent is obtained by a method including a step of mixing the curing agent, and optionally the urethane (meth) acrylic copolymer, the curing catalyst, the organic solvent and / or the additive by various known means. To be

  The undercoat agent may be used as an undercoat agent for transfer foil, an undercoat agent for in-mold injection molding method transfer foil, and the like.

[the film]
The present disclosure provides a film in which an undercoat agent cured product layer containing a cured product of the undercoat agent is laminated on at least one surface of the film.

  As the base material, various known materials are adopted. The base material is a polycarbonate film, an acrylic film (polymethylmethacrylate film, etc.), a polystyrene film, a polyester film, a polyolefin film, an epoxy resin film, a melamine resin film, a triacetyl cellulose film, an ABS film, an AS film, a norbornene resin film, a ring. Examples include olefin films and polyvinyl alcohol films. The thickness of the base material is not particularly limited, but is preferably about 50 to 200 μm. The thickness of the undercoat layer is not particularly limited, but is preferably about 0.1 to 5 μm.

  The film is manufactured by various known methods. In one embodiment, the method for producing a film includes a step of applying an undercoating agent to at least one surface of a substrate (coating step), and a step of forming a cured undercoating agent layer by thermosetting (thermosetting step). )including. In one embodiment, an undercoat agent cured product layer is laminated on the active energy ray curable resin cured product layer in the film. In that case, the process of applying the undercoating agent cured product layer to the active energy ray curable resin (coating step), the step of drying if necessary (drying step), and the irradiation of active energy rays The method further includes a step of forming a cured product layer of an energy ray curable resin (active energy ray curing step).

(Coating process)
Examples of the coating method include bar coater coating, wire bar coating, Meyer bar coating, air knife coating, gravure coating, reverse gravure coating, offset printing, flexographic printing, and screen printing.

The coating amount is not particularly limited. The amount of coating is preferably about 0.1 to 30 g / m ² after drying, and more preferably about 1 to ²⁰ g / m ² .

(Thermosetting process)
Examples of the drying method include drying with a circulating air dryer. Examples of the drying conditions include 120 ° C. and standing for 60 seconds.

  When manufacturing a film, an aging process is performed after drying if necessary. As an example, aging treatment or the like at 40 ° C. for 72 hours is exemplified.

(Active energy ray curing process)
Examples of the active energy ray used in the active energy ray curing reaction include ultraviolet rays and electron rays. Examples of the ultraviolet light source include a xenon lamp, a high-pressure mercury lamp, and an ultraviolet irradiation device having a metal halide lamp. The amount of light, the arrangement of light sources, the transport speed, etc. can be adjusted as necessary. When a high-pressure mercury lamp is used, it is preferable to cure one lamp having a light amount of usually 80 to 160 W / cm at a transportation speed of 5 to 50 m / min. On the other hand, in the case of an electron beam, it is preferable to cure the electron beam with an electron beam accelerating device having an accelerating voltage of about 10 to 300 kV at a conveying speed of about 5 to 50 m / min.

  The active energy ray-curable resin is a radical-curable resin such as (meth) acrylic ester, urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, polyacryl (meth) acrylate (for example, Arakawa Chemical Co., Ltd. "Beamset series" manufactured by Kogyo Co., Ltd.)), epoxides, oxetanes, vinyl ethers, and other resins that are cured by cations or anions, and resins that are cured by the ene-thiol reaction between alkenes and thiols. These may be used in combination.

  Hereinafter, the present invention will be specifically described through examples and comparative examples. However, the above description of the preferred embodiments and the following examples are provided for the purpose of illustration only and are not provided for the purpose of limiting the present invention. Accordingly, the scope of the invention is not limited to the embodiments or examples specifically described herein, but only by the claims. In addition, in each of the examples and comparative examples, the numerical values such as parts and% are based on mass unless otherwise specified.

Example 1-1: Production of curing agent A polyisocyanate adduct (product name "Takenate D120N": hydrogenated xylylene diisocyanate) was placed in a reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel and a nitrogen inlet tube. 600.0 parts by mass of an addition reaction product of trimethylolpropane, hereinafter hydrogenated XDI adduct, 18.6 parts by mass of 2-hydroxyethyl acrylate (hereinafter HEA), 1.4 parts by mass of water, and 316. 5 parts by mass were charged, and a urethane / urea reaction was carried out at 60 ° C. for 2 hours. Then, by cooling to room temperature, a modified polyisocyanate adduct (solid content 50%, solid content 100%, isocyanate group content: 5.6%) was obtained.

The isocyanate group content of the modified polyisocyanate adduct was measured by the following method using an automatic potentiometric titrator (manufactured by Kyoto Electronics Manufacturing Co., Ltd.).
1) 0.5 g of the sample was collected in a 200 mL Erlenmeyer flask.
2) 20 mL of dehydrated toluene was added to dissolve the sample.
3) 10.0 mL of 0.2 mol / L di-normal butylamine solution was added.
4) Shake to homogenize and leave for 20 minutes or longer.
5) 100 mL of isopropyl alcohol was added.
6) Titration was performed using a 0.1 mol / L hydrochloric acid solution.
7) A blank test was conducted by the same operation, and the isocyanate group content was calculated using the following formula.
Isocyanate group content = (SIZE / ((BL1-EP1) × FA1)) × K2
EP1: Titration amount (mL)
BL1: Blank value FA1: Factor of titrant (1.00)
K2: Coefficient (1000)
SIZE: sampling amount (g)

Examples 1-2 to 1-4, Comparative examples 1-1 to 1-2
Examples 1-2 to 1-4 and Comparative Examples 1-1 to 1-2 were produced in the same manner as Example 1-1, except that the component compositions were changed as shown in the table below.

TMP: trimethylolpropane

Production Example 1: Production of urethane (meth) acrylic copolymer 306.6 parts by mass of methyl methacrylate (hereinafter, also referred to as MMA) is placed in a reaction vessel equipped with a stirrer, a thermometer, a reflux cooling tube, a dropping funnel and a nitrogen introducing tube. , N-butyl methacrylate (hereinafter also referred to as BMA) 84.0 parts by mass, 2-hydroxyethyl methacrylate (hereinafter also referred to as HEMA) 29.4 parts by mass, and methyl ethyl ketone 630 parts by mass were charged, and a reaction system was prepared. It was set to 60 ° C. Then, 2.1 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) was charged, and the mixture was kept warm at around 60 ° C. for 8 hours. Next, 4.2 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) was charged, and the reaction system was kept at the same temperature for about 4 hours. Next, 350 parts by mass of methyl ethyl ketone and 1.9 parts by mass of hydrogenated xylylene diisocyanate were charged, and the mixture was kept at about 75 ° C. for 3 hours. Then, the reaction system was cooled to room temperature to obtain a urethane (meth) acrylic copolymer solution (nonvolatile content 30%).

Example 2-1: Production of Undercoat Agent 41.7 parts of the urethane (meth) acrylic copolymer of Production Example 1, 40.0 parts of the curing agent of Example 1-1, and dioctyltin dilaurate (solid content as a curing catalyst) A concentration of 100% or less, 0.25 part of DOTDL, 81.1 parts of methyl ethyl ketone (hereinafter, MEK) and 1.8 parts of acetylacetone (hereinafter, AcAc) as an organic solvent were used. A coating agent having a solid content concentration of 20% was prepared by thoroughly mixing the above components.

Examples 2-1 to 2-5, Comparative examples 2-1 to 2-2
Examples 2-2 to 2-5 and Comparative examples 2-1 to 2-2 were carried out in the same manner as Example 2-1 except that the type and amount of the curing agent were changed as shown in the table below.

(Manufacture of active energy ray curable resin)
A 4-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen inlet and a dropping funnel was charged with 3- (2H-1,2,3-benzotriazol-2-yl) -4-hydroxyphenethylmethacrylate. Latte 11 parts, glycidyl methacrylate 49.8 parts, methyl methacrylate 15 parts, azobisisobutyronitrile 3 parts, and butyl acetate 100 parts were charged and stirred, and the temperature was raised to 100 ° C. under a nitrogen stream and reacted for 10 hours. . After that, 24.2 parts of acrylic acid, 0.1 part of 4-methoxyphenol, and 0.3 parts of triphenylphosphine as a reaction catalyst were charged, and reacted at 100 ° C. for 8 hours to obtain an active energy ray-curable resin (nonvolatile component 50%).

(Production of evaluation film)
A coating liquid was prepared by adding 5 parts of a photopolymerization initiator 1-hydroxycyclohexyl phenyl ketone (trade name "Irgacure 184" BASF, hereinafter, Irg184) to the obtained active energy ray-curable resin. Then, an active energy ray-curable resin was applied onto a polyethylene terephthalate film that had been subjected to a mold release treatment so that the film thickness after drying was 5 to 6 μm, and after drying at 80 ° C. for 1 minute, 25 mJ / UV pre-cure was performed at cm ² . Next, the undercoat agents according to Examples 1 to 5 and Comparative Examples 1 to 3 were applied onto the active energy ray-curable resin cured material layer so that the film thickness after drying was 1 μm, and the temperature was 80 ° C. × 5. A second drying was carried out. Next, an undercoat layer for vapor deposition was applied on the cured undercoat agent layer so that the film thickness after drying was 1 μm, and drying was performed at 120 ° C. for 1 minute. Using the coated film obtained up to this step, the evaluation of printability was carried out. As the undercoat layer for vapor deposition, "Aracoat DA105 / Aracoat CL102H" manufactured by Arakawa Chemical Co., Ltd. was used.
Then, the coating film was subjected to aluminum vapor deposition (film thickness 50 nm) using a commercially available vapor deposition device (product name “VPC-1100”, manufactured by ULVAC Kiko Co., Ltd.). Further, an adhesive was applied on the aluminum vapor-deposited layer so that the film thickness was 1 μm, and dried at 80 ° C. for 10 seconds.

(Manufacture of evaluation panels)
The obtained film was heat-transferred to a commercially available acrylic plate, UV after-cured at 300 mj / cm ² , and then used as a test panel. Test panels were similarly prepared for the undercoat agents of the other Examples and Comparative Examples.

(Printability)
The appearance immediately after applying the vapor deposition undercoat layer was visually evaluated. The evaluation criteria are as follows.
5: No defective appearance is observed even after overprinting.
4 ... A slight coating streak is partially seen.
3: Coating streaks are visible on the entire surface.
2 ... Coating streaks are seen on the entire surface, and unevenness is also seen partially.
1 ... Coating streaks are seen on the entire surface, and irregularities are also seen.

(Initial adhesion)
Using the test panel obtained by the above method, a cellophane tape cross-cut peeling test was performed.

(Moisture and heat resistance)
The UV adhesion after 85 ° C. and 85% × 72 hours was evaluated by a cellophane tape cross-cut peeling test.

(Light tight adhesion)
With an accelerated light resistance tester (Super UV tester), illuminance was 50 mW / cm ² , and after 168 hours, evaluation was performed by a cellophane tape cross-cut peeling test.

The evaluation criteria for initial adhesion, moist heat resistance, and light adhesion are as follows.
5: No peeling is observed.
4 ... Less than 5% peeling is observed between the active energy ray-curable resin layer and the anchor layer.
3 ... 5% or more and less than 20% peeling is observed between the active energy ray-curable resin layer and the anchor layer.
2 ... 20% or more and less than 50% peeling is observed between the active energy ray-curable resin layer and the anchor layer.
1 ... 50% to 100% peeling is observed between the active energy ray-curable resin layer and the anchor layer.

Claims (5)

A curing agent containing a modified polyisocyanate adduct, which is a reaction product of a compound group containing a polyisocyanate adduct, water and a hydroxyl group-containing compound, and has an isocyanate group content of 13 mass% or less at a solid content of 100 mass%. The curing agent according to claim 1, wherein the polyisocyanate adduct is a reaction product of hydrogenated xylylene diisocyanate and trimethylolpropane. An undercoat agent containing the curing agent according to claim 1. The undercoat agent according to claim 3, comprising a urethane (meth) acrylic copolymer which is a reaction product of a hydroxyl group-containing (meth) acrylic copolymer and polyisocyanate. A film in which an undercoating agent cured product layer containing the cured product of the undercoating agent according to claim 3 is laminated on at least one surface of the film.