JP7183789B2 - Use as primer composition, aqueous liquid, base film with primer layer, prism sheet and primer composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a primer composition, more specifically, a primer composition for forming a primer layer on a base film, an aqueous liquid using the primer composition, a base film with a primer layer, a prism sheet and a primer. It relates to use as a composition.

BACKGROUND ART Conventionally, synthetic resins have been widely used as resins for various base materials because they have excellent properties such as dimensional stability, mechanical properties, heat resistance, transparency, electrical properties and chemical resistance. For example, polyester films are used in various industrial fields such as packaging materials, magnetic cards, and printing materials. In addition, another resin is mixed with other resins as required, melt-extruded, molded, biaxially stretched, and heat-set. Such a polyester film has excellent physical properties, but has a problem of poor adhesion to a coating layer provided on the film because its surface is highly crystalline.

Therefore, in order to improve the adhesion between the polyester film and the coating layer, studies have been made to impart adhesion to the film surface. It is known how to set

One of the coating layers is, for example, a prism layer, and a prism sheet comprising a polyester film and a prism layer is used in display devices such as televisions, personal computers, and mobile phones.

As a method for forming the prism layer, for example, the active energy ray-curable resin composition is introduced into the prism mold, and the active energy ray is irradiated while the active energy ray-curable resin composition is sandwiched between the prism mold and the polyester film. Then, the resin composition is cured and the prism mold is removed to form a prism layer formed by curing the active energy ray-curable resin composition on the polyester film.

In the case of such a method, it is necessary to use a non-solvent type active energy ray-curable resin in order to form a prism pattern with precision.
However, the solvent-free resin has a lower penetration and swelling effect into the primer layer laminated on the polyester film than the solvent-based resin, and the layer and the primer layer formed by curing the active energy ray-curable resin composition Adhesion to is likely to be insufficient.

Therefore, as a technique for improving the adhesion between the polyester film and the prism layer, for example, Patent Document 1 proposes a technique for forming a primer layer with a coating liquid containing a (meth)acrylate compound and an isocyanate compound. discloses a laminated polyester film having, on at least one surface of the polyester film, a coating layer formed from a coating liquid containing a (meth)acrylate compound and an isocyanate compound.

Japanese Patent Application Laid-Open No. 2014-133401

Since the base film with the primer layer is rolled up and stored, the untreated surface of the base film comes into contact with the surface of the primer layer. The material films may become difficult to separate from each other, or the primer layer may migrate or fuse to the untreated surface of the base film. Therefore, anti-blocking property is also required to prevent excessive adhesion between the surface of the primer layer of the base film and the untreated surface.

The technique of Patent Document 1 shows an effect of adhesion to the prism layer. On the other hand, with regard to blocking resistance, a method of adding fine particles such as silica to the primer coating is described. In some cases, the adhesiveness of the toner deteriorates, and the anti-blocking property is not sufficient even with the addition of fine particles.

Under such circumstances, the present invention aims to improve the adhesion between both the substrate film and the coating layer, particularly between the polyester film and the prism layer formed by curing the solvent-free active energy ray-curable resin composition. It is an object of the present invention to provide a primer composition for forming a primer layer which is excellent in blocking resistance and does not migrate or fuse to the untreated surface of a base film.

As a result of intensive studies to solve the above problems, the present inventors found that the above problems can be solved by using a primer composition containing (meth)acrylamides and a cross-linking agent, and completed the present invention. Arrived.

That is, the present invention is characterized by the following (1) to (14).
(1) A primer composition containing (meth)acrylamides (A) and a cross-linking agent (B).
(2) The cross-linking agent (B) is an isocyanate-based compound, an oxazoline-based compound, an epoxy-based compound, a carbodiimide-based compound, an amine-based compound, a metal-based compound, an aziridine-based compound, a hydrazine-based compound, a hydrazide-based compound and a melamine-based compound. The primer composition according to (1) above, which is at least one compound selected from the group consisting of:
(3) The primer composition according to (1) or (2) above, wherein the (meth)acrylamides (A) are hydroxyl group-containing (meth)acrylamides.
(4) The primer composition according to any one of (1) to (3) above, wherein the (meth)acrylamides (A) have a carbon-carbon double bond content of 1 to 40% by mass. .
(5) Any one of (1) to (4) above, wherein the (meth)acrylamides (A) in the primer composition have a carbon-carbon double bond content of 0.5 to 35% by mass. The described primer composition.
(6) Any one of the above (1) to (5), wherein the content ratio (mass ratio) of the (meth)acrylamides (A) and the crosslinking agent (B) is 10:90 to 90:10 The described primer composition.
(7) The primer composition according to any one of (1) to (6) above, further comprising a binder resin (C).
(8) The primer composition according to (7) above, wherein the binder resin (C) is a polyester resin.
(9) The primer composition according to (7) or (8) above, wherein the content of the binder resin (C) in the primer composition is 1 to 70% by mass.

(10) An aqueous liquid obtained by dissolving or dispersing the primer composition according to any one of (1) to (9) in an aqueous solvent.
(11) A base film with a primer layer having a primer layer formed of the primer composition according to any one of (1) to (9) on the base film.
(12) A prism sheet having a prism layer on the primer layer of the base film with a primer layer according to (11).
(13) The prism sheet according to (12) above, wherein the prism layer is a cured product of a solvent-free active energy ray-curable resin composition.
(14) Use of a composition containing (meth)acrylamides (A) and a cross-linking agent (B) as a primer composition.

According to the present invention, it is possible to obtain a primer layer which not only has excellent adhesion between the base film and the coating layer, but also has excellent blocking resistance such that the primer layer does not migrate or adhere to the untreated surface of the base film. A primer composition can be provided. Therefore, the base film with a primer layer having a primer layer made of the primer composition of the present invention is suitable for a sheet having a coating layer on a film such as a prism sheet, a label sheet, a printing sheet, and a hard coat film. Available.

The present invention will be described in detail below.
In the present invention, (meth)acrylamide means acrylamide or methacrylamide, (meth)acrylate means acrylate or methacrylate, and (meth)acryloyl group means methacryloyl group or acryloyl group.
In the present invention, the term "sheet" conceptually includes sheets, films, and tapes.
Moreover, in the present invention, "mass" is synonymous with "weight".

<Primer composition>
The primer composition of the present invention contains (meth)acrylamides (A) and a cross-linking agent (B).
Each component will be described below.

<(Meth)acrylamides (A)>
The primer composition of the present invention contains (meth)acrylamides (A).
For example, when the primer composition of the present invention is used to form a primer layer provided between a substrate film and a coating layer using a prism layer formed by curing a solvent-free active energy ray-curable resin, The (meth)acryloyl group in the (meth)acrylamides (A) reacts with the double bond in the coating layer during curing of the solvent-free active energy ray-curable resin. Therefore, the primer layer obtained from the primer composition of the present invention has excellent adhesion between the substrate film and the coating layer. Furthermore, the amide group in the (meth)acrylamides (A) has a high polarity, thereby further improving the adhesion.

Moreover, the blocking resistance of the primer layer obtained from the primer composition of the present invention is improved due to the intermolecular hydrogen bonding between the amide groups. Furthermore, when the (meth)acrylamides (A) have a hydroxyl group and the cross-linking agent (B) is an isocyanate compound described later, the hydrogen bond between the urethane bond site and the amide group generated by the reaction between the hydroxyl group and the isocyanate group , the blocking resistance is further improved.

(Meth)acrylamides (A) include, for example, monofunctional (meth)acrylamides, difunctional (meth)acrylamides, trifunctional or higher polyfunctional (meth)acrylamides, and one or more of these are used.

Monofunctional (meth)acrylamides include, for example, (meth)acrylamide, dimethyl(meth)acrylamide, diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide and other (di)alkyl(meth)acrylamides, N-methoxymethyl (Meth)acrylamide, alkoxyalkyl (meth)acrylamide such as Nn-butoxymethyl (meth)acrylamide, Ni-butoxymethyl (meth)acrylamide, dimethylaminopropyl (meth)acrylamide, dimethylaminopropyl (meth)acrylamide Amino group-containing (meth)acrylamides such as methyl chloride quaternary salts, ketone group-containing (meth)acrylamides such as diacetone (meth)acrylamide, N-hydroxymethyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide and the like Examples include hydroxyl group-containing (meth)acrylamide, and (meth)acryloylmorpholine.

Bifunctional (meth)acrylamides include, for example, N,N'-methylenebis(meth)acrylamide and the like, and typical commercial products thereof include "FAM-201" manufactured by Fuji Film Co., Ltd., and the like. .

Examples of tri- or higher polyfunctional (meth)acrylamides include commercially available products such as "FAM-301", "FAM-401" and "FAM-402" manufactured by Fuji Film.

The (meth)acrylamides (A) used in the present invention are preferably compounds having an acrylamide group from the viewpoint of adhesion to solvent-free active energy ray-curable resins that are preferably used as prism resins. In addition, from the viewpoint of blocking resistance, the (meth)acrylamides (A) should contain functional groups such as hydroxyl groups, amino groups, carboxyl groups, epoxy groups, and ketone groups, and should be reactive with the cross-linking agent (B). It preferably contains a group having a, particularly preferably a hydroxyl group, a carboxyl group, or a ketone group, and more preferably a hydroxyl group.

In particular, hydroxyl group-containing (meth)acrylamides having a hydroxyl group are most preferred in terms of reactivity with the cross-linking agent (B) and adhesion with the solvent-free active energy ray-curable resin.
The hydroxyl group-containing (meth)acrylamides include, for example, N-methylol(meth)acrylamide, N-hydroxyethyl(meth)acrylamide and the like, among which N-hydroxyethyl(meth)acrylamide is preferred.

The hydroxyl value of the hydroxyl-containing (meth)acrylamides is preferably from 20 to 800 mgKOH/g, more preferably from 50 to 700 mgKOH/g, more preferably from 100 to 600 mgKOH/g. If the hydroxyl value is too small, the adhesion to the non-solvent type active energy ray-curable resin and blocking resistance tend to decrease, and if it is too large, the water resistance of the primer layer tends to decrease.
In addition, said hydroxyl value is the value measured according to JISK1557.

(Meth)acrylamides (A) are preferably those with a low molecular weight that tend to be unevenly distributed on the surface of a coating film made of a primer composition, from the viewpoint of adhesion to non-solvent type active energy ray-curable resins. The weight average molecular weight of the (meth)acrylamides (A) is preferably 10,000 or less, more preferably 1,000 or less, more preferably 500 or less, and most preferably 200 or less. The lower limit of the weight average molecular weight is usually 70. If the weight-average molecular weight is too large, there is a tendency for adhesion to non-solvent type active energy ray-curable resins and the like to decrease.

In the present invention, the weight average molecular weight and number average molecular weight are the weight average molecular weight and number average molecular weight in terms of standard polystyrene molecular weight. Use two series of SuperMultipore HZ-M (exclusion limit molecular weight: 2×10 ⁶ , number of theoretical plates: 16,000 plates/line, filler material: styrene-divinylbenzene copolymer, filler particle diameter: 4 μm) It is measured by

Monofunctional (meth)acrylamides or bifunctional (meth)acrylamides are preferred, and monofunctional (meth)acrylamides are particularly preferred, since they tend to be unevenly distributed on the surface of a coating film composed of a primer composition.

In addition, the carbon-carbon double bond content in the (meth)acrylamides (A) is preferably 1 to 40% by mass from the viewpoint of adhesion to solvent-free active energy ray-curable resins and the like. . Specifically, the lower limit is preferably 1% by mass or more, particularly 2% by mass or more, further preferably 3% by mass or more, and particularly preferably 5% by mass or more. If the carbon-carbon double bond content is too small, there is a tendency for adhesion to non-solvent type active energy ray-curable resins and the like to decrease.

The carbon-carbon double bond content in the (meth)acrylamides (A) is calculated by the following formula (I).
Carbon-carbon double bond content (% by mass) in (meth)acrylamides (A)=(100×27×P1 _n )/P1 _mw Formula (I)
In formula (I), P1 _n is the number of carbon-carbon double bonds per molecule of (meth)acrylamides (A), and P1 _mw is the molecular weight (g/mol) of (meth)acrylamides (A). .

Furthermore, in the present invention, the carbon-carbon double bond content of (meth)acrylamides (A) in the primer composition is preferably 0.5 to 35% by mass. Specifically, the lower limit is preferably 0.5% by mass or more, particularly 1% by mass or more, further preferably 2% by mass or more, and particularly preferably 4% by mass or more. If the carbon-carbon double bond content is too small, there is a tendency for adhesion to non-solvent type active energy ray-curable resins and the like to decrease.

The carbon-carbon double bond content of the (meth)acrylamides (A) in the primer composition is calculated by the following formula (II).
Carbon-carbon double bond content (% by mass) of (meth)acrylamides (A) in the primer composition = (100 × 27 × P2 _m × P2 _n ) / (P2 _mw × S2) formula ( II)
In formula (II), P2 _m is the mass (g) of (meth)acrylamides (A), P2 _n is the number of carbon-carbon double bonds per molecule of (meth)acrylamides (A), and P2 _mw is The molecular weight (g/mol) of the (meth)acrylamides (A) and S2 are the total solid mass (g) of the primer composition.

The content of (meth)acrylamides (A) in the primer composition is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 20% by mass or more, and particularly 25% by mass or more. preferred. The upper limit is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 80% by mass or less, and particularly preferably 75% by mass or less. If the content of the (meth)acrylamides (A) is too low or too high, the adhesion between the base film and the coating layer tends to decrease, and the blocking resistance tends to decrease.

<Crosslinking agent (B)>
Examples of the cross-linking agent (B) include isocyanate compounds, oxazoline compounds, epoxy compounds, carbodiimide compounds, amine compounds, metal compounds, aziridine compounds, hydrazine compounds, hydrazide compounds and melamine compounds. It is preferred to use at least one compound selected from the group consisting of By using these compounds, the tackiness of the primer layer is reduced, the strength of the coating film made of the primer composition is improved, and the wettability of coating agents such as solvent-free active energy ray-curable resins is improved. The adhesion to non-solvent active energy ray-curable resins and the like is improved.

Among these, the cross-linking agent (B) is particularly preferably an isocyanate-based compound, an oxazoline-based compound, or a carbodiimide-based compound, more preferably an isocyanate-based compound, from the viewpoint of adhesion to a non-solvent active energy ray-curable resin or the like. .

The isocyanate-based compound may contain at least two isocyanate groups as functional groups in the molecule. Compound; xylylene diisocyanate compounds such as 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate and tetramethylxylylene diisocyanate; aromatic isocyanate compounds such as 1,5-naphthalene diisocyanate and triphenylmethane triisocyanate ; hexamethylene diisocyanate, isophorone diisocyanate, adducts of these isocyanate compounds and polyol compounds such as trimethylolpropane, burettes and isocyanurates of these polyisocyanate compounds, and the like.

Specifically, "Aquanate 110" and "Aquanate 210" manufactured by Nippon Polyurethane Co., Ltd., "Elastron BN-27" and "Elastron BN-77" manufactured by Daiichi Kogyo Seiyaku Co., Ltd., and "Elaston BN-77" manufactured by Meisei Chemical Industry Co., Ltd. Meikanate TP-10", "SU-268A", "Trixene aqua BI200" and "Trixene aqua BI220" manufactured by Baxenden Chemical Limited.

Among them, aliphatic isocyanate or alicyclic isocyanate is more preferable than aromatic isocyanate in order to avoid yellowing due to ultraviolet rays. From the viewpoint of stability, the functional group block type is preferable, and "SU-268A", "Trixene aqua BI220" and the like are preferable.

Examples of oxazoline compounds include addition-polymerizable 2-oxazolines having a substituent having an unsaturated carbon-carbon bond at the 2-position carbon position (e.g., 2-isopropenyl-2-oxazoline) and other unsaturated monomers. Examples include copolymers with monomers, and commercially available products manufactured by Nippon Shokubai Co., Ltd. "Epocross WS-500", "Epocross WS-700", "Epocross K-2010E", "Epocross K-2020E", " Epocross K-2030E" and the like.

Examples of epoxy-based compounds include bisphenol A/epichlorohydrin type epoxy resins, sorbitol polyglycidyl ether (e.g., "Denacol EX-611", "Denacol EX-612", and "Denacol EX-614" manufactured by Nagase ChemteX Corporation). , "Denacol EX-614B", "Denacol EX-622", etc.), polyglycerol polyglycidyl ether (e.g., "Denacol EX-512", "Denacol EX-521", etc. manufactured by Nagase ChemteX Corporation), pentaerythritol poly glycidyl ether (e.g., "Denacol EX-411" manufactured by Nagase ChemteX Corporation), diglycerol polyglycidyl ether (e.g., "Denacol EX-421" manufactured by Nagase ChemteX Corporation), glycerol polyglycidyl ether (e.g., "Denacol EX-313" and "Denacol EX-314" manufactured by Nagase ChemteX Corporation), trimethylolpropane polyglycidyl ether (for example, "Denacol EX-321" manufactured by Nagase ChemteX Corporation), resorcinol diglycidyl ether (eg, "Denacol EX-201" manufactured by Nagase ChemteX Corporation), neopentyl glycol diglycidyl ether (eg, "Denacol EX-211" manufactured by Nagase ChemteX Corporation), 1,6-hexanediol diglycidyl Ethers (eg, "Denacol EX-212" manufactured by Nagase ChemteX Corporation), hydrogenated bisphenol A diglycidyl ethers (eg, "Denacol EX-252" manufactured by Nagase ChemteX Corporation), ethylene glycol diglycidyl Ether (e.g., Nagase ChemteX Co., Ltd. "Denacol EX-810", "Denacol EX-811", etc.), diethylene glycol diglycidyl ether (e.g., Nagase ChemteX Co., Ltd. "Denacol EX-850", "Denacol EX- 851” etc.), polyethylene glycol diglycidyl ether (for example, “Denacol EX-821”, “Denacol EX-830”, “Denacol EX-832”, “Denacol EX-841”, “Denacol EX” manufactured by Nagase Chemtex Co., Ltd.) -861”, etc.), propylene glycol diglycidyl ether (e.g., Nagase ChemteX Co., Ltd. “Denacol EX-911”, etc.), polypropylene glycol diglycidyl ether (e.g., Nagase ChemteX Co., Ltd. “Denaco and "Denacol EX-941", "Denacol EX-920", "Denacol EX-931" and the like.
Among them, the water-based type is preferred.

The carbodiimide-based compound may contain at least two carbodiimide groups as functional groups or cyanamide groups having a tautomeric relationship thereof in the molecule. 02", "Carbodilite V-02-L2", "Carbodilite SV-02", "Carbodilite V-04", "Carbodilite V-10", "Carbodilite E-03A", "Carbodilite E-02", "Carbodilite E -04” and the like.

Examples of amine compounds include hexamethylenediamine and triethanolamine.

Examples of metal compounds include metal alkoxides such as tetraethyl titanate, tetraethyl zirconate, and aluminum isopropionate, and metal alkoxides such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, and zirconium. Acetylacetone, acetoacetate, metal chelate compounds of ethylenediaminetetraacetic acid coordination compounds of polyvalent metals, acetic acid-ammonium complex salts of the above polyvalent metals, ammonium-carbonate complex salts of the above polyvalent metals, and the like.

Any aziridine-based compound containing at least two aziridine groups may be used, and examples thereof include "Kemitite PZ-33" and "Kemitite DZ-22E" manufactured by Nippon Shokubai Co., Ltd.

Examples of hydrazine compounds include hydrazine monohydrochloride, hydrazine dihydrochloride, hydrazine monohydrobromide, and hydrazine carbonate.

Examples of hydrazide compounds include adipic acid dihydrazide, sebacic acid dihydrazide, dodecanediohydrazide, isophthalic acid dihydrazide, salicylic acid hydrazide, and the like.

Examples of melamine compounds include hexamethoxymethylol melamine, Sanwa Chemical Co., Ltd. "Nikalac MW-30M", "Nikalac MW-30", "Nikalac MW-22", "Nikalac MS-11", and "Nikalac MS-011", "Nikalac MX-730", "Nikalac MX-750", "Nikalac MX-706", "Nikalac MX-035" methylated melamine resins, "Nikalac MX-45", "Nikalac MX- 410" and other mixed etherified melamine resins.

As the cross-linking agent (B), only one selected from these may be used, or two or more thereof may be used in combination.

The content of the cross-linking agent (B) in the primer composition can be appropriately selected depending on the amount of functional groups of the (meth)acrylamides (A), the weight average molecular weight of the (meth)acrylamides (A), and the purpose of use. It is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, and particularly preferably 18% by mass or more. The upper limit is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 80% by mass or less, and particularly preferably 75% by mass or less. If the content of the cross-linking agent (B) is too low or too high, cross-linking will be insufficient, and there will be a tendency for adhesion to the non-solvent type active energy ray-curable resin and blocking resistance to decrease.

In the present invention, the content ratio (mass ratio) of the (meth)acrylamides (A) and the cross-linking agent (B) in the primer composition should be From the viewpoint of blocking properties, the ratio of (meth)acrylamides (A):crosslinking agent (B) is preferably 10:90 to 90:10, particularly preferably 15:85 to 85:15, more preferably 20: 80 to 80:20, particularly preferably 25:75 to 75:25. If the amount of the cross-linking agent (B) is too small or too large relative to the (meth)acrylamides (A), the adhesion to the solvent-free active energy ray-curable resin and the like and blocking resistance tend to decrease. .

In the present invention, when the most preferred hydroxyl group-containing (meth)acrylamides are used as the (meth)acrylamides (A) and the most preferred isocyanate compounds are used as the cross-linking agent (B), the primer The content ratio of the hydroxyl group of the hydroxyl group-containing (meth)acrylamides to the isocyanate group of the cross-linking agent (B) (hydroxyl group content: isocyanate group content) (molar ratio) is preferably 100:1 to 100:300. , particularly preferably 100:3 to 100:150, more preferably 100:5 to 100:100, particularly preferably 100:10 to 100:70. If the isocyanate group content is too small, adhesion to non-solvent type active energy ray-curable resins and blocking resistance will tend to decrease. tend to cause

In the present invention, it is preferable to use a curing catalyst in order to promote the reaction of (meth)acrylamides (A), the cross-linking agent (B), and the binder resin (C), which will be described later.
Examples of such curing catalysts include metal compounds such as organotin compounds, organotitanium compounds, and organozirconia compounds, and amine compounds. Organotin compounds are preferred.
The content of the curing catalyst is preferably 0.01 to 5 parts by mass, particularly preferably 0.1 to 2 parts by mass, more preferably 0.5 to 1.5 parts by mass, based on 100 parts by mass of the primer composition. be.

<Binder resin (C)>
Various polymers are used as binders in the primer composition of the present invention in order to improve coating appearance, transparency, adhesion, etc., and to support the (meth)acrylamides (A) and the cross-linking agent (B). It is also possible to use together as resin (C).

Specific examples of the binder resin (C) include, for example, polyurethane-based resins, polyester-based resins, acrylic-based resins, vinyl-based resins (polyvinyl alcohol, etc.), polyalkylene glycol, polyalkyleneimine, methylcellulose, hydroxycellulose, starches, and the like. is mentioned. Among them, polyurethane-based resins, polyester-based resins, and acrylic-based resins are preferred from the viewpoint of improving adhesion, polyester-based resins and acrylic-based resins are particularly preferred, and polyester-based resins are further preferred.

A polyurethane-based resin is a polymer compound having a urethane bond in its molecule, and is usually produced by a reaction of a polyol and an isocyanate. Polyols include polyester polyols, polycarbonate polyols, polyether polyols, polyolefin polyols, and acrylic polyols, and these compounds may be used singly or in combination.

Examples of polyester-based resins include those composed of polyvalent carboxylic acids and polyol compounds as described below as main constituents.
Examples of polyvalent carboxylic acids include terephthalic acid, isophthalic acid, orthophthalic acid, phthalic acid, 4,4′-diphenyldicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6- Aromatic dicarboxylic acids such as naphthalenedicarboxylic acid and 2,7-naphthalenedicarboxylic acid, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid and 1,3-cyclohexanedicarboxylic acid, 2-potassium sulfoterephthalic acid, 5- Sulfonic acid metal salt-containing dicarboxylic acids such as sodium sulfoisophthalic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, glutaric acid, aliphatic dicarboxylic acids such as succinic acid, trimellitic acid, trimesic acid, pyromellitic acid , trimellitic anhydride, pyromellitic anhydride, and the like, tri- or more functional polycarboxylic acids, p-hydroxybenzoic acid, and other hydroxyl acids and their ester-forming derivatives.

Examples of polyol compounds include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 2- Aliphatic diols such as methyl-1,5-pentanediol and neopentyl glycol, alicyclic diols such as 1,4-cyclohexanedimethanol and 1,3-cyclohexanedimethanol, p-xylylene glycol , Aromatic diols such as bisphenol A-ethylene glycol adducts, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polytetramethylene oxide glycol, etc. Polyether diols, carboxyl group-containing diols such as dimethylolpropionic acid and dimethylolbutanoic acid, and tri- or higher functional polyols such as glycerin and trimethylolpropane can be used.

One or more of these compounds may be appropriately selected, and a polyester resin may be synthesized by a conventional polycondensation reaction. Among these polyester-based resins, those containing a constituent component having a sulfonate from the viewpoint of making it water-based, or having an acid value of 10 or more are preferable, and have good adhesion to solvent-free active energy ray-curable resins and the like. From a point of view, those containing constituents with sulfonates are particularly preferred.

An acrylic resin is a polymer composed of a polymerizable monomer having a carbon-carbon double bond, such as a (meth)acrylate monomer. These may be homopolymers or copolymers. Also included are copolymers (eg, block copolymers, graft copolymers) of these polymers and other polymers (eg, polyesters, polyurethanes, etc.). Alternatively, a polymer obtained by polymerizing a polymerizable monomer having a carbon-carbon double bond in a polyester solution or a polyester dispersion (sometimes a mixture of polymers) is also included. Also included are polymers obtained by polymerizing polymerizable monomers having carbon-carbon double bonds in polyurethane solutions and polyurethane dispersions (mixtures of polymers in some cases). Polymers (polymer mixtures in some cases) obtained by polymerizing polymerizable monomers having carbon-carbon double bonds in other polymer solutions or dispersions are also included.

The polymerizable monomer having a carbon-carbon double bond is not particularly limited, but particularly representative compounds include, for example, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, citracone Various carboxyl group-containing monomers such as acids, and salts thereof; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, monobutylhydroxyl fumarate, various hydroxyl-containing monomers such as monobutyl hydroxyitaconate; various (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, lauryl (meth)acrylate; acrylic acid alkyl esters; various nitrogen-containing vinyl monomers such as (meth)acrylamide, diacetoneacrylamide, N-methylolacrylamide or (meth)acrylonitrile; styrene, α-methylstyrene, divinylbenzene, vinyltoluene; various styrene derivatives such as vinyl esters such as vinyl acetate and vinyl propionate; various silicon-containing polymerizable monomers such as γ-methacryloxypropyltrimethoxysilane and vinyltrimethoxysilane; monomers; various vinyl halides such as vinyl chloride and pyridene chloride; and various conjugated dienes such as butadiene.

The content of the binder resin (C) is preferably 3 to 200 parts by mass, particularly 5 to 100 parts by mass, with respect to a total of 100 parts by mass of the (meth)acrylamides (A) and the cross-linking agent (B). parts, more preferably 8 to 60 parts by mass.

The content of the binder resin (C) in the primer composition is preferably 1% by mass or more, particularly preferably 5% by mass or more, further preferably 7% by mass or more, and 70% by mass or less. preferably 60% by mass or less, more preferably 50% by mass or less, and particularly preferably 40% by mass or less. When the binder resin (C) is contained, if the content of the binder resin (C) is too small, the transparency of the coating film made of the primer composition tends to decrease due to poor film formation, etc. When the contents of (meth)acrylamides (A) and cross-linking agent (B) are too small, it tends to be difficult to achieve both adhesion and blocking resistance.

In addition to the above components, the primer composition of the present invention may optionally contain antioxidants such as hindered phenols, heat stabilizers, glass fibers, inorganic/organic fillers, colorants, flame retardants, and softeners. Agents, dispersants, wetting agents, emulsifiers, gelling agents, antifoaming agents, other thermoplastic resins, etc. can be blended to such an extent that the effects of the present invention are not impaired.

The primer composition of the present invention can be produced by mixing (meth)acrylamides (A), a cross-linking agent (B), and optionally a binder resin (C) and other components.

<Aqueous liquid>
The aqueous liquid of the present invention is obtained by dissolving or dispersing the primer composition in an aqueous solvent. Hereinafter, dissolving or dispersing in an aqueous solvent is referred to as "water dissolution or water dispersion".
When preparing the aqueous liquid of the present invention, at least the above (meth)acrylamides (A) and the cross-linking agent (B), preferably further the binder resin (C), can be appropriately mixed with the aqueous solvent. For example, (1) a method of mixing each component and then mixing an aqueous solvent to obtain an aqueous liquid of the present invention, (2) a method of preparing an aqueous liquid of each component with an aqueous solvent and mixing them to obtain an aqueous liquid of the present invention. and (3) a method in which at least one of the components is made into an aqueous liquid with an aqueous solvent, and the remaining components are mixed to form the aqueous liquid of the present invention. These methods are easy to prepare. The above method (2) or (3) is preferable in that respect.

Examples of the aqueous solvent include water or a mixture of water and an appropriate hydrophilic organic solvent.
Examples of the hydrophilic organic solvent include ketones such as acetone; alcohols such as methanol, ethanol, and isopropyl alcohol; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, and ethylene glycol monotertiary butyl ether; Examples thereof include those miscible with water, such as carboxylic acid esters such as diisobutyl acid, diisobutyl glutarate, and diisobutyl adipate.

When a hydrophilic organic solvent is used, the content ratio of the aqueous liquid of the present invention to the whole is appropriately set. For example, it can be set to a range of 20% by mass or less, but is not limited to this. Also, one kind selected from these hydrophilic organic solvents may be used, or two or more kinds may be used in combination.

(Meth)acrylamides (A) and the cross-linking agent (B), preferably the binder resin (C) are dissolved or dispersed in an aqueous solvent to prepare an aqueous liquid. It is preferable to incorporate a neutralizing agent in order to dissolve or disperse uniformly in the liquid.

Any neutralizing agent may be used as long as it can neutralize the acidic groups of the (meth)acrylamides (A), the cross-linking agent (B) and the binder resin (C) contained in the primer composition. Specifically, for example, lithium hydroxide, potassium hydroxide, metal hydroxides such as sodium hydroxide; ethylamine, diethylamine, triethylamine, propylamine, isopropylamine, iminobispropylamine, 3-ethoxypropylamine, 3- organic amines such as diethylaminopropylamine, diethanolamine, triethanolamine, N,N-diethylethanolamine, N,N-dimethylethanolamine, aminoethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine; mentioned. One type selected from these neutralizing agents may be used, or two or more types may be used in combination.

Among these neutralizing agents, those having a boiling point of 150° C. or lower are preferable from the viewpoint of easy volatilization by drying and water resistance of the primer layer. In particular, ammonia and triethylamine are preferred, and ammonia is particularly preferred, from the viewpoints of high versatility, low boiling point, and easy volatilization during drying.

Further, the aqueous liquid of the present invention may optionally contain a surfactant such as an anionic surfactant or a nonionic surfactant. By blending the surfactant, the wettability of the base film can be improved when the aqueous liquid is applied to the polyester resin base such as a polyester film.
Suitable surfactants can be used, for example, polyoxyethylene alkylphenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, glycerin fatty acid ester, fatty acid metal soap, alkyl sulfate, alkyl sulfonate, Alkyl sulfosuccinate, dodecyl benzene sulfonate and the like can be mentioned. One selected from these surfactants may be used, or two or more may be used in combination.
From the viewpoint of the adhesion between the coating layer and the primer layer and the water resistance of the primer layer, it is preferable not to add a surfactant.

In addition, the aqueous liquid of the present invention may further contain antistatic agents, fillers, ultraviolet absorbents, lubricants, colorants, and the like, if necessary.

The concentration of solids in the aqueous liquid of the present invention is appropriately adjusted so as to ensure good dispersibility of the (meth)acrylamides (A), the cross-linking agent (B), and preferably the binder resin (C). For example, 5 to 30% by mass is preferable. When applied to the substrate film, it is diluted appropriately to obtain a desired film thickness, for example, the solid content concentration is adjusted to 1 to 15% by mass before use.

<Base film with primer layer>
The aqueous liquid of the present invention is applied to a base film and dried by heating to obtain a primer composition containing (meth)acrylamides (A) and a cross-linking agent (B), more preferably a binder resin (C). A coated film (primer layer) can be formed to obtain a base film with a primer layer.

Examples of the base film include polyester resins such as polyethylene naphthalate, polyethylene-2,6-naphthalate, polyethylene terephthalate, polybutylene terephthalate, and polyethylene terephthalate/isophthalate copolymer; polyethylene, polypropylene, polymethylpentene, and the like. Polyolefin resin; polyvinyl fluoride, polyvinylidene fluoride, polyethylene fluoride resin such as polyethylene fluoride; nylon 6, polyamide such as nylon 6,6; polyvinyl chloride, polyvinyl chloride / vinyl acetate copolymer, ethylene- vinyl polymers such as vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol and vinylon; cellulose-based resins such as cellulose triacetate and cellophane; polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, Acrylic resins such as polybutyl acrylate; and synthetic resin films or sheets such as polystyrene, polycarbonate, polyarylate, and polyimide.
Among them, a polyester film is preferably used from the viewpoints of transparency, chemical resistance, heat resistance, mechanical strength and cost.
The polyester film may be either unstretched or stretched, but a stretched film is preferred, and a biaxially stretched film is particularly preferred.

As a method for applying the aqueous liquid, a known general method can be used, and examples thereof include a method of applying to one side or both sides of the base film by kiss coating, reverse coating, gravure coating, die coating, or the like.

The thickness of the primer layer after drying by heating (after cross-linking) is preferably 0.01 to 2 μm, more preferably 0.02 to 0.5 μm, particularly 0.03 to 0.3 μm, particularly It is preferably 0.05 to 0.15 μm. If the thickness is too thin, the adhesion tends to decrease, and if it is too thick, optical properties such as transparency and haze tend to decrease, and blocking resistance tends to decrease.

<Laminated film/prism sheet>
A laminated film or a prism sheet can be obtained by further providing a coating layer on the primer layer of the base film with the primer layer, and using the coating layer as a hard coat layer or a prism layer.
Examples of materials for forming the coating layer include acrylic resins, epoxy resins, urethane resins, and active energy ray-curable resin compositions that are commonly used as coating materials. A flexible resin composition is preferred.

<<Laminated film>>
The laminated film is obtained by coating the active energy ray-curable resin composition on the primer layer of the base film with the primer layer, and curing by irradiating the active energy ray to form the primer layer of the base film with the primer layer. It can be obtained by forming a hard coat layer formed by curing an active energy ray-curable resin composition thereon.

The thickness of the hard coat layer is usually 0.5 to 15 μm, preferably 1 to 10 μm, particularly preferably 2 to 7 μm.

<<prism sheet>>
The prism sheet can be obtained by forming a prism layer on the primer layer of the base film with the primer layer.
The prism layer is preferably a cured product of an active energy ray-curable resin composition, more preferably a cured product of a solvent-free active energy ray-curable resin composition.

As a method for forming the prism layer when the prism layer is a cured product of the active energy ray-curable resin composition, for example, the active energy ray-curable resin composition is introduced into the prism type, and the prism type and the primer layer are formed. The active energy ray-curable resin composition is irradiated with the active energy ray-curable resin composition sandwiched between the primer layer side of the base film (especially the polyester film), and the active energy ray-curable resin composition is cured to form a prism type. is removed to form a cured product of the active energy ray-curable resin composition on the substrate film.

The method of applying the active energy ray-curable resin composition is not particularly limited, and examples thereof include spray, shower, dipping, roll, spin, curtain, flow, slit, die, gravure, comma, dispenser, Wet coating methods such as screen printing, inkjet printing and the like are included.

Examples of active energy rays that can be used include light rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, infrared rays, electromagnetic waves such as X rays and γ rays, electron beams, proton beams, neutron beams, and the like. Curing by ultraviolet irradiation is advantageous because of availability of equipment, price, and the like.
As a method of curing by ultraviolet irradiation, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, a chemical lamp, an electrodeless discharge lamp, an LED, etc. that emit light in the wavelength range of 150 to 450 nm are used. , 30 to 3,000 mJ/cm ² .
After the ultraviolet irradiation, heating may be performed as necessary to complete curing.

The thickness of the prism layer is preferably 5 to 50 μm, more preferably 10 to 45 μm, more preferably 15 to 40 μm, most preferably 20 to 35 μm.

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples unless it exceeds the gist of the invention.
Measurement methods and evaluation methods used in Examples and Comparative Examples are as follows.
In the following, "parts" and "%" are based on mass.

The following ingredients were prepared.

<(Meth)acrylamides (A)>
(A-1): N-methylolacrylamide (“N-MAM” manufactured by Kasano Kosan Co., Ltd.) (hydroxyl value: 487 mgKOH/g, carbon-carbon double bond content: 26.7% by mass)
(A-2): N-hydroxyethylacrylamide ("HEAA" manufactured by KJ Chemicals) (hydroxyl value: 555 mgKOH/g, carbon-carbon double bond content: 23.4% by mass)

The following compounds were prepared as comparative compounds.
(A'-1): Trimethylolpropane ethylene oxide-modified triacrylate (total ethylene oxide units = 15/1 molecule) ("T-70EA" manufactured by Toho Chemical Industry Co., Ltd.)

<Crosslinking agent (B)>
(B-1): Nonionic blocked isocyanate aqueous dispersion having a 1,6-hexamethylene diisocyanate trimer skeleton (“Trixene aqua BI220” manufactured by Baxenden Chemicals Limited (solid content 40%, isocyanate group equivalent 400 g/mol ( Solid content value)))
(B-2): Oxazoline group-containing polymer water dispersion (“Epocross WS-700” manufactured by Nippon Shokubai Co., Ltd. (solid content: 25%, oxazoline group equivalent: 220 g/mol (solid content)))

<Binder resin (C)>
(C-1): Aqueous liquid of polyester resin prepared according to Production Example 1 below (solid concentration: 20%)

[Production Example 1]
A thermometer, a stirrer, a rectifying column, and a reactor equipped with a nitrogen inlet tube were charged with 252 parts (1.517 mol) of terephthalic acid, 135 parts (0.813 mol) of isophthalic acid, and 5-sodium as polyvalent carboxylic acid components. 60 parts (0.203 mol) of dimethyl sulfoisophthalate, 248 parts (3.995 mol) of ethylene glycol as a polyol component, 6 parts (0.057 mol) of diethylene glycol, 0.3 parts of zinc (II) acetate as a catalyst, diantimony trioxide 0.4 was charged, the temperature was raised over 2 hours until the internal temperature reached 200 to 240° C., and the esterification reaction was carried out at 240° C. for 3 hours. After that, the pressure inside the system was reduced to about 1 mmHg, and a polycondensation reaction was carried out at an internal temperature of 240° C. to obtain a polyester resin.
The resulting polyester resin had an acid value of 3 mgKOH/g, a number average molecular weight of 8,300, a weight average molecular weight of 12,700 and a glass transition temperature of 51°C.

Next, 20 parts of the obtained polyester resin, 80 parts of deionized water, and 0.1 part of 25% aqueous ammonia are charged into a reactor, heated to 90° C. and dissolved with stirring to obtain a solid content concentration of 20%. An aqueous liquid (aqueous dispersion) of a polyester resin was prepared.

<Examples 1 to 5 and Comparative Example 1>
Using the (meth)acrylamides (A) and the cross-linking agent (B) prepared above, each component was mixed so that the solid content mass ratio as shown in Table 1, Examples 1 to 5 and Comparative A primer composition of Example 1 was prepared.

In Examples 1 to 4, the content ratio of the hydroxyl groups of (meth)acrylamides (A) and the isocyanate groups of the cross-linking agent (B) in the obtained primer composition (hydroxyl group amount:isocyanate group amount) (molar ratio) was It was obtained by the following formula (III). In Example 5, the content ratio (hydroxyl group amount:oxazoline group amount) (molar ratio) of the hydroxyl group of the (meth)acrylamides (A) and the oxazoline group of the cross-linking agent (B) in the primer composition was determined. . Table 1 shows the results.

Hydroxyl group content: isocyanate group content (or oxazoline group content) (molar ratio) = {(H _m × H _n )/(H _mw )}: {I _m /I _mw } Formula (III)
In formula (III), H _m is the mass (g) of the hydroxyl-containing compound, H _n is the number of hydroxyl groups per molecule of the hydroxyl-containing compound, H _mw is the molecular weight of the hydroxyl-containing compound (g/mol), and _Im is isocyanate. The mass (g) of the group-containing compound (or oxazoline group-containing compound), _Imw , is the isocyanate group equivalent (or oxazoline group equivalent) (g/mol).
In addition, in Table 1, the amount of hydroxyl groups:the amount of isocyanate groups (or the amount of oxazoline groups) (molar ratio) when the amount of hydroxyl groups is converted to 100 is described.

The resulting primer composition was evaluated for adhesion to a resin layer obtained by curing a solvent-free UV-curable resin composition for forming a prism layer and blocking resistance according to the following methods. Table 1 shows the results.

[Adhesion]
The primer composition prepared above was diluted with deionized water so that the solid content of the aqueous composition liquid was 3% to prepare a coating liquid of the primer composition. The prepared coating solution was coated on a PET film (manufactured by Toray Industries, Inc., Lumirror T60, thickness 100 μm) using a bar coater No. 1. 6 and dried at 150° C. for 3 minutes to form a primer layer with a thickness of 0.2 μm.

Next, a solvent-free UV-curable resin composition "Sunrad A" (manufactured by Sanyo Chemical Industries, Ltd.) for forming a prism layer was applied onto the primer layer using an applicator, followed by application at a height of 13 cm from the coating surface. A high-pressure mercury lamp having an irradiation intensity of 80 W/cm was set at a low temperature to irradiate ultraviolet rays at 450 mJ/cm ² to cure the ultraviolet-curable resin composition, thereby forming a resin layer having a thickness of 25 μm.

100 cross-cuts of 1 mm ² were put in the UV-curable resin layer thus formed, and Cellotape (registered trademark) manufactured by Nichiban Co., Ltd. was pasted thereon, and the tape was rubbed with a plastic eraser to ensure sufficient adhesion. After that, it was rapidly peeled off in the 90° direction, and adhesion was evaluated based on the number of squares in which the resin layer remained. The evaluation criteria were as follows, and ⊚ and ◯ were regarded as good adhesion.

(Evaluation criteria)
◎: 98/100 or more (remaining number / measured number)
○: 86/100 or more, 97/100 or less △: 66/100 or more, 85/100 or less ×: 65/100 or less

[Blocking resistance]
The primer composition prepared above was diluted with deionized water so that the solid content of the aqueous composition liquid was 20% to prepare a coating liquid of the primer composition. The prepared coating solution was coated on a PET film (manufactured by Toray Industries, Inc., Lumirror T60, thickness 100 μm) using a bar coater No. 1. 10 and dried at 150° C. for 3 minutes to form a primer layer with a thickness of 2 μm.

The two PET films with a primer layer obtained above were placed on the surface of one PET film with a primer layer on the primer layer side and the surface on the base film side of the other PET film with a primer layer (no primer layer is provided). The untreated surface) was placed in contact with the substrate, and left overnight under a pressure of 6.2 g/cm ² at 23° C. and a relative humidity of 50%. After that, the blocking resistance was evaluated by checking the adhesion state of the two primer-layer-attached PET films. Evaluation criteria are as follows.

(Evaluation criteria)
Good: Two sheets of primer layer-attached PET films are not adhered to each other, or two sheets of primer layer-attached PET films are easily peeled off, and no transfer of the primer layer to the untreated surface or fusion marks are observed.
x: Two sheets of the PET film with the primer layer are in close contact, or when the two sheets of the PET film with the primer layer are peeled off, the transfer of the primer layer to the untreated surface or a fused mark is observed.

From the results in Table 1, the primer compositions of Examples 1 to 5 contain the (meth)acrylamides (A) and the cross-linking agent (B). It was found to be excellent in resistance to blocking as well as in resistance to blocking.
On the other hand, Comparative Example 1 used an acrylate compound instead of (meth)acrylamides (A), and thus was inferior in blocking resistance.

<Examples 6 to 8>
Using the (meth)acrylamides (A), the cross-linking agent (B) and the binder resin (C) prepared above, each component was mixed so that the solid content mass ratio as shown in Table 2 was obtained. The primer compositions of Examples 6-8 were prepared.

The content ratio (hydroxyl group content: isocyanate group content) (molar ratio) of the hydroxyl groups of the (meth)acrylamides (A) and the isocyanate groups of the cross-linking agent (B) in the obtained primer composition was determined in the same manner as in Example 1. asked. Table 2 shows the results.

The resulting primer composition was evaluated for adhesion and blocking resistance to a resin layer obtained by curing the above-described solvent-free UV-curable resin composition for forming a prism layer. evaluated the sex. Table 2 shows the results.

〔transparency〕
The primer composition prepared above was diluted with deionized water so that the solid content of the aqueous composition liquid was 3% to prepare a coating liquid of the primer composition. The prepared coating solution was coated on a PET film (manufactured by Toray Industries, Inc., Lumirror T60, thickness 100 μm) using a bar coater No. 1. 6 and dried at 150° C. for 3 minutes to form a primer layer with a thickness of 0.2 μm.
The PET film with the primer layer obtained above was visually observed, and the transparency was evaluated according to the following evaluation criteria.

(Evaluation criteria)
◯: The transparency is high, and no clouding of the film or defective film formation is visually observed.
Δ: Slightly lacking in transparency, and when held up to light, the film is visually observed to be cloudy, defective in film formation, and the like.
x: Lack of transparency, cloudiness of the film, defective film formation, etc. are clearly observed by visual observation.

From the results in Table 2, the primer compositions of Examples 6 to 8 contained (meth)acrylamides (A), cross-linking agent (B), and polyester resin as binder resin (C). As a result, it was found that the transparency was also excellent.

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 (Japanese Patent Application No. 2017-129132) filed on June 30, 2017, the contents of which are incorporated herein by reference.

The primer composition of the present invention can be suitably used as a primer for base films. In addition, the obtained substrate film with a primer layer has excellent adhesion to the coating layer formed by curing the active energy ray-curable resin composition. Examples include label sheets, printing sheets, hard coat films, It is useful as a sheet such as a prism sheet provided with a coating layer on a film, and is particularly useful as a prism sheet.

Claims (10)

A sheet having a base film, a primer layer on the base film, and a coating layer on the primer layer,
The primer layer is a primer layer made of a primer composition containing a (meth)acrylamide group-containing compound (A) and a cross-linking agent (B),
The cross-linking agent (B) includes an isocyanate group-containing compound, an oxazoline group-containing compound, an epoxy group-containing compound, a carbodiimide group-containing compound, an amino group-containing compound, a metal alkoxide, a metal chelate compound, a polyvalent metal acetic acid-ammonium complex salt, a poly at least one compound selected from the group consisting of an ammonium-carbonate complex salt of a valent metal, an aziridine group-containing compound, a hydrazine group-containing compound, a hydrazide group-containing compound and a melamine group-containing compound;
The sheet, wherein the content ratio (mass ratio) of the (meth)acrylamide group-containing compound (A) and the cross-linking agent (B) is 10:90 to 90:10. 2. The sheet according to claim 1, wherein the (meth)acrylamide group-containing compound (A) is a hydroxyl group-containing (meth)acrylamide group-containing compound. 3. The sheet according to claim 1, wherein the (meth)acrylamide group-containing compound (A) has a carbon-carbon double bond content of 1 to 40% by mass. The sheet according to any one of claims 1 to 3, wherein the (meth)acrylamide group-containing compound (A) in the primer composition has a carbon-carbon double bond content of 0.5 to 35% by mass. The sheet according to any one of claims 1 to 4, further comprising a binder resin (C). The sheet according to claim 5, wherein the binder resin (C) is polyester. 7. The sheet according to claim 5, wherein the content of the binder resin (C) in the primer composition is 1 to 70% by mass. The sheet according to any one of claims 1 to 7, wherein the primer composition is an aqueous liquid dissolved or dispersed in an aqueous solvent. The sheet according to any one of claims 1 to 8, wherein said coating layer is a prismatic layer. 10. The sheet according to claim 9 , wherein the prism layer is a cured product of a solvent-free active energy ray-curable resin composition.