JP5365038B2 - UV curable paint, hard coat layer, transparent polycarbonate sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultraviolet-curable coating material capable of imparting wear resistance and anti-blocking property to a transparent plastic material at low cost. <P>SOLUTION: The ultraviolet-curable coating material is formed of a resin composition containing ultraviolet-curable resin (A) containing multifunctional urethane (meth)acrylate oligomer and at least one monomer component selected from a multifunctional (meth)acrylate monomer and a monofunctional (meth)acrylate monomer and having an average number of functional groups of 1.9-8.2, at least one polymer selected from a (meth)acrylic polymer (B) compatible with the ultraviolet-curable resin (A) and having a polar group in a side chain, a styrene-based polymer (C) and an acryl-styrene copolymer (D), and a photopolymerization initiator. The mass ratio of at least one polymer selected from the (meth)acrylic polymer (B), styrene-based polymer (C) and acryl-styrene copolymer (D) to the ultraviolet-curable resin (A) is 60/40-99.5/0.5. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

The present invention relates to an ultraviolet curable paint , a hard coat layer, and a transparent polycarbonate sheet .

  In the present specification and claims, the term “(meth) acrylate” means “acrylate or methacrylate”. The term “(meth) acryl” means “acryl or methacryl”.

  Conventionally, for example, protective equipment for human bodies such as sports goggles, helmet shields, windshields, safety glasses, safety shields, precision instrument applications such as various display and instrument display covers, lenses, sensor covers, in homes and stores Anti-prevention of surface sticking to various transparent plastic materials used for partitioning and showcases, for residential use, for partition plates and shelves in automobiles and railway vehicles, instrument covers, and transportation-related applications such as windows As a means to impart anti-glare properties that prevent blocking and glare caused by light reflection, a hard coat with fine irregularities due to the contained fine particles on its surface by applying a coating containing organic and inorganic fine particles dispersedly A method of forming a layer is disclosed (for example, see Patent Document 1).

JP 2002-182015 A

  However, when using a paint in which fine particles are dispersed and contained as in the prior art, it is technically very difficult to uniformly disperse the fine particles in the paint itself. For example, a hard coat paint can be obtained by using special fine particles. There is a problem that the cost is very high, and that the optical properties of the hard coat layer to be formed are deteriorated due to the dispersion and inclusion of fine particles.

  The present invention has been made in view of such a technical background, and is used as a coating material for forming a hard coat layer or the like on the surface of a transparent plastic material or the like. An object of the present invention is to provide an ultraviolet curable coating material capable of expressing fine irregularities on the surface and thus imparting abrasion resistance and antiblocking property to a transparent plastic material at a low cost.

  In order to achieve the above object, the present invention provides the following means.

(1) A polyfunctional urethane (meth) acrylate oligomer and at least one monomer component selected from the group consisting of a polyfunctional (meth) acrylate monomer and a monofunctional (meth) acrylate monomer are contained, and the average number of functional groups is 1 .9-8.2 ultraviolet curable resin (A), (meth) acrylic polymer (B) having compatibility with the ultraviolet curable resin (A) and having a polar group in the side chain; A resin composition containing at least one polymer selected from styrene-based polymer (C) and acrylic-styrene copolymer (D) and a photopolymerization initiator, and (meth) for the ultraviolet curable resin (A) At least one polymer selected from an acrylic polymer (B), a styrene polymer (C), and an acrylic-styrene copolymer (D); Mass ratio, 60/40 to 99.5 / 0.5 ultraviolet curable coating material, characterized in that.

(2) The (meth) acrylic polymer (B) is a (meth) acryl obtained by polymerizing a polymerization component containing a (meth) acrylic monomer and a monomer having an unsaturated double bond and a polar group. The ultraviolet curable paint according to (1), which contains a copolymer.

(3) The styrene polymer (C) includes a styrene copolymer obtained by polymerizing a polymerization component containing a styrene monomer and a monomer having an unsaturated double bond and a polar group (1 ) UV curable paint.

(4) The acrylic-styrene copolymer (D) is an acrylic polymer obtained by polymerizing a polymerization component containing a (meth) acrylic monomer, a styrene monomer, and a monomer having an unsaturated double bond and a polar group. The ultraviolet curable paint according to (1), which contains a styrene copolymer.

(5) The ultraviolet ray according to any one of (1) to (4), wherein the polar group includes at least one polar group selected from a benzophenone group, a benzophenolate group, a benzotriazole group, and a hindered amine group. Curing paint.

(6) The polyfunctional urethane (meth) acrylate oligomer is a polyfunctional urethane (meth) acrylate which is a reaction product of an isocyanate compound obtained by reacting a polyol and diisocyanate and a (meth) acrylate monomer having a hydroxyl group. The ultraviolet curable paint according to (1), which comprises an oligomer.

  According to the present invention, it is used as a paint for forming a hard coat layer or the like on the surface of a transparent plastic material or the like, and can express fine irregularities on the surface of the coating film without using fine particles, Accordingly, it is possible to provide an ultraviolet curable paint capable of imparting abrasion resistance and antiblocking property to a transparent plastic material at a low cost.

The ultraviolet curable coating material of the present invention contains a polyfunctional urethane (meth) acrylate oligomer and at least one monomer component selected from the group consisting of a polyfunctional (meth) acrylate monomer and a monofunctional (meth) acrylate monomer. UV curable resin (A) having an average functional group number of 1.9 to 8.2;
Selected from (meth) acrylic polymer (B) having compatibility with the ultraviolet curable resin (A) and having a polar group in the side chain, styrene polymer (C) and acrylic-styrene copolymer (D) One kind of polymer,
A photopolymerization initiator;
A resin composition containing
The mass ratio of the (meth) acrylic polymer (B), the styrene polymer (C) and the acrylic-styrene copolymer (D) to the ultraviolet curable resin (A) is 60/40 to It is 99.5 / 0.5.
The ultraviolet curable paint according to the invention of (1) is applied to the surface of a plastic material or the like, dried, and then irradiated with ultraviolet rays to form a coating film by crosslinking and curing the ultraviolet curable resin (A) component. Then, fine irregularities appear on the surface of the coating film, and the fine irregularities can give excellent antiblocking properties, and the coating film is transparent and excellent in wear resistance, and also improves the adhesion to the plastic material. Can do.

In the invention of (2), a (meth) acrylic polymer obtained by polymerizing a polymerization component containing a (meth) acrylic monomer and a monomer having an unsaturated double bond and a polar group as the (meth) acrylic polymer. Since the copolymer is used, the anti-blocking property of the coating film can be further improved without impairing the wear resistance and adhesion.

In the invention of (3), a styrene copolymer obtained by polymerizing a polymerization component containing a styrene monomer and a monomer having an unsaturated double bond and a polar group is used as the styrene polymer. Therefore, the antiblocking property of the coating film can be further improved without impairing the wear resistance and adhesion.

In the invention of (4), as the acrylic-styrene copolymer, a polymerization component containing a (meth) acrylic monomer, a styrene monomer, and a monomer having an unsaturated double bond and a polar group is polymerized (meta ) Since the acrylic-styrene copolymer is used, the anti-blocking property of the coating film can be further improved without impairing the wear resistance and adhesion.

In the invention of (5), since the polar group is at least one polar group selected from the group consisting of a benzophenone group, a benzophenolate group, a benzotriazole group, and a hindered amine group, the antiblocking property of the coating film is further improved. Can be improved.

In the invention of (6), as a polyfunctional urethane (meth) acrylate oligomer, a polyfunctional urethane (which is a reaction product of an isocyanate compound obtained by reacting a polyol and diisocyanate and a (meth) acrylate monomer having a hydroxyl group ( Since the (meth) acrylate oligomer is used, the wear resistance and adhesion of the coating film can be further improved.

  A coating film (hard coat layer, etc.) formed by applying the ultraviolet curable coating material of the present invention to the surface of a plastic material or the like in the form of a solution of an appropriate solvent, drying and then irradiating with ultraviolet rays. It is possible to develop fine irregularities that provide excellent anti-blocking properties and excellent wear resistance on the surface of the surface.

  The generation mechanism of such fine irregularities is not clear, but in the process of drying and curing with ultraviolet rays, the ultraviolet curable resin (A) and the (meth) acrylic polymer (B), the styrene polymer (C) and It is presumed that at least one monomer selected from the acryl-styrene copolymer (D) causes phase separation to cause appropriate fine irregularities on the surface of the coating film. That is, since at least one monomer selected from the (meth) acrylic polymer (B), the styrene polymer (C), and the acrylic-styrene copolymer (D) has a polar group in the side chain, In the course of curing by UV, at least one monomer selected from the ultraviolet curable resin (A) and the (meth) acrylic polymer (B), the styrene polymer (C), and the acrylic-styrene copolymer (D) undergoes phase separation. It is estimated that moderate fine irregularities appear on the surface of the coating film.

  In addition, since at least one monomer selected from the (meth) acrylic polymer (B), the styrene polymer (C), and the acrylic-styrene copolymer (D) has compatibility with the ultraviolet curable resin (A), It does not form fine particles (fine particles as in the prior art) in the cured coating film.

In the ultraviolet curable paint of the present invention, at least one monomer selected from an ultraviolet curable resin (A), a (meth) acrylic polymer (B), a styrene polymer (C), and an acrylic-styrene copolymer (D) Is set in the range of 60/40 to 99.5 / 0.5.
The mass ratio of the ultraviolet curable resin (A) and at least one monomer selected from the (meth) acrylic polymer (B), the styrene polymer (C), or the acrylic-styrene copolymer (D) is in the above range. By this, sufficient coating film adhesion and antiblocking properties can be imparted. Furthermore, it is preferably set in the range of 80/20 to 95/5. This improves the adhesion to the coating film and further improves the anti-blocking property.

  The average number of functional groups of the ultraviolet curable resin (A) is in the range of 1.9 to 8.2 (pieces / molecule). If the average number of functional groups is less than 1.9, sufficient abrasion resistance cannot be imparted to the coating film, and if the average number of functional groups exceeds 8.2, the coating film becomes brittle and easily breaks and wear resistance also decreases. To do. The “average functional group number” means the average functional group number (weight average functional group number) averaged by weight.

  The polyfunctional urethane (meth) acrylate oligomer (a1) constituting the ultraviolet curable resin (A) is not particularly limited. For example, an isocyanate compound obtained by reacting a polyol and diisocyanate; A polyfunctional urethane (meth) acrylate oligomer that is a reaction product with a (meth) acrylate monomer having a hydroxyl group is suitable. This polyfunctional urethane (meth) acrylate oligomer (a1) contributes to imparting sufficient abrasion resistance to the coating film. That is, in the structure which does not contain this polyfunctional urethane (meth) acrylate oligomer (a1), the coating film becomes brittle and the abrasion resistance becomes insufficient.

  The number average molecular weight of the polyfunctional urethane (meth) acrylate oligomer (a1) is preferably in the range of 800 to 5000.

  The polyol that is a raw material for synthesizing the isocyanate compound is not particularly limited, and examples thereof include polyester polyols, polyether polyols, polycarbonate polyols, and the like. It may be good, and 2 or more types may be used together.

  The polyester polyol is not particularly limited in the production method. For example, a polycondensation reaction between a diol and a dicarboxylic acid or dicarboxylic acid chloride, an esterification of a diol or a dicarboxylic acid, and an ertel exchange reaction is performed. What is obtained can be used.

  The diol used for the synthesis of the polyester polyol is not particularly limited. For example, ethylene glycol, propylene glycol, 1,4 monobutane diol, 1,6 monohexane diol, diethylene glycol, dipropylene glycol, Examples include ethylene glycol, tripropylene glycol, tetraethylene glycol, and tetrapropylene glycol. The dicarboxylic acid used for the synthesis of the polyester polyol is not particularly limited. For example, adipic acid, succinic acid, glutaric acid, pimelic acid, sebacic acid, azelaic acid, dimaleic acid, terephthalic acid, isophthalic acid Examples include acid and phthalic acid.

  Although it does not specifically limit as said polyether polyol, For example, a polyethylene oxide, a polypropylene oxide, an ethylene oxide propylene oxide random copolymer etc. are mentioned.

  The polycarbonate polyol is not particularly limited, and examples thereof include reaction products obtained by polycondensation of the following component Q and component R. That is, the component Q is not particularly limited, and examples thereof include 1,4 monobutanediol, 1,6 monohexane diol, neopentyl glycol, 1,8 monooctane diol, and 1,9 monononane diol. 1,4 monocyclohexanedimethanol, bismethylpropanediol, dipropylene glycol, diethylene glycol and other diols, or these diols and succinic acid, malonic acid, succinic acid, adipic acid, azelaic acid, hexahydrophthalic acid Reaction products with dicarboxylic acids such as In addition, the component R is not particularly limited, and examples thereof include diphenyl carbonate, bis (chlorophenyl) carbonate, dinaphthyl carbonate, phenyl toluyl carbonate, phenyl chlorophenyl carbonate, 2 1 triru 4 1 tolyl carbonate, and dimethyl carbonate. And aromatic carbonates such as diethyl carbonate, diethylene carbonate, and ethylene carbonate, or aliphatic carbonates.

  Although it does not specifically limit as diisocyanate which is a synthetic raw material of the said isocyanate compound, A linear or cyclic aliphatic diisocyanate is suitable. Specific examples thereof include, but are not limited to, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate and the like.

  The (meth) acrylate monomer having a hydroxyl group is not particularly limited. For example, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol triacrylate, 2-hydroxy-11-acryloxy-31 And methacryloxypropane, 2-hydroxy-1,31 dimethacryloxypropane, and the like. Note that these (meth) acrylate monomers are not limited to one type, and two or more types may be used in combination.

  The (meth) acrylic monomer component (a2) constituting the ultraviolet curable resin (A) is at least one selected from the group consisting of a polyfunctional (meth) acrylate monomer and a monofunctional (meth) acrylate monomer. Used. Only a polyfunctional (meth) acrylate monomer may be used, only a monofunctional (meth) acrylate monomer may be used, or both may be used together.

  The polyfunctional (meth) acrylate monomer as the monomer component (a2) is not particularly limited, and examples thereof include dipropylene glycol diacrylate, tripropylene glycol diacrylate, dimethylol dicyclopentane diacrylate, 1 , 9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 2-methyl-1,8-octanediol di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, ethylene Ethoxylated cyclohexanedimethanol di (meth) acrylate, dipentaerythritol hexaacrylate, pentaerythritol triacrylate, 1,6-one hexanediol dimethacrylate having an average added mole number of oxide of 4 to 10 Over doors and the like.

  Further, the monofunctional (meth) acrylate monomer as the monomer component (a2) is not particularly limited, and examples thereof include isobornyl acrylate, isostearyl acrylate, octyl acrylate, decyl acrylate, and paracumylphenoxyethylene. Examples include glycol acrylate, isoborinyl methacrylate, and paracumylphenoxyethylene glycol methacrylate.

  The mass ratio of the polyfunctional urethane (meth) acrylate oligomer (a1) and the (meth) acrylic monomer component (a2) used in the ultraviolet curable resin (A) is 90/10 at (a1) / (a2). It is preferable to be in the range of ~ 70/30.

  Next, the (meth) acrylic polymer (B), styrene polymer (C), and acrylic-styrene copolymer (D) will be described. The (meth) acrylic polymer (B), styrene polymer (C) and acrylic-styrene copolymer (D) are compatible with the ultraviolet curable resin (A) and have a polar group in the side chain. (Meth) acrylic polymer, styrenic polymer or acrylic-styrene copolymer is used. The (meth) acrylic polymer (B), styrene polymer (C) or acrylic-styrene copolymer (D) does not include the polyfunctional urethane (meth) acrylate oligomer (a1).

  Although it does not specifically limit as said polar group, For example, an amino group, a quaternary ammonium functional group, a benzophenone group, a benzophenolate group, the following general formula (I);

（但し、式中Ｍは水素原子、アルカリ金属またはアンモニウム塩を示す）で表される官能基、下記一般式（ＩＩ）；

(Wherein M represents a hydrogen atom, an alkali metal or an ammonium salt), the following general formula (II);

（但し、式中Ｍは水素原子、アルカリ金属またはアンモニウム塩を示す）で表される官能基、下記一般式（ＩＩＩ）；

(Wherein M represents a hydrogen atom, an alkali metal or an ammonium salt), the following general formula (III);

（但し、式中Ｍは水素原子、アルカリ金属またはアンモニウム塩を示す）で表される官能基、下記一般式（ＩＶ）；

(Wherein M represents a hydrogen atom, an alkali metal or an ammonium salt), the following general formula (IV);

で表されるベンゾトリアゾール基、下記一般式（Ｖ）；

A benzotriazole group represented by the following general formula (V);

（但し、式中Ｒは、一Ｈまたは一ＣＨ３を示す）で表されるヒンダードアミン基、
下記一般式（ＶＩ）；

(Wherein R represents 1H or 1CH3), a hindered amine group represented by:
The following general formula (VI);

（但し、式中Ｘはハロゲン原子を示す）で表される官能基、等が挙げられる。

(Wherein X represents a halogen atom), and the like.

The number average molecular weight of the (meth) acrylic polymer (B), styrene polymer (C), or acrylic-styrene copolymer (D) is preferably 500 to 500,000.
When the number average molecular weight of the polymer exceeds the lower limit, the polarity of the side chain can be sufficiently increased, and the fine unevenness of the coating film can be sufficiently expressed. Moreover, the abrasion resistance of a coating film can fully be improved because a number average molecular weight is less than the said upper limit. Among these, the number average molecular weight of the (meth) acrylic polymer (B), styrene polymer (C), or acrylic-styrene copolymer (D) is more preferably 5,000 to 150,000.

  As said (meth) acrylic-type polymer (B), although the homopolymer of the (meth) acrylic-type monomer which has a polar group can also be used, from a viewpoint of the ease of reaction control and an antiblocking improvement, ( It is preferable to use a copolymer obtained by polymerizing a polymerization component containing a (meth) acrylic monomer (having no polar group) (b1) and a monomer (b2) having an unsaturated double bond and a polar group. As the polymerization method, for example, various polymerization methods such as a solution polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method can be employed.

 Similarly, as the styrenic polymer (C), for example, a homopolymer of a styrenic monomer having a polar group can be used. From the viewpoint of easy reaction control and improvement of antiblocking properties, a styrenic monomer (polar It is preferable to use a copolymer obtained by polymerizing a polymerization component containing (c1) having no group) and a monomer (b2) having an unsaturated double bond and a polar group. As the polymerization method, for example, various polymerization methods such as a solution polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method can be employed.

  Similarly, as the acrylic-styrene copolymer (D), for example, a copolymer of an acrylic monomer having a polar group and a styrene monomer can be used, but from the viewpoint of ease of reaction control and improvement of antiblocking property, A polymerization component containing an acrylic monomer (having no polar group) (b1) and a styrene monomer (having no polar group) (c1) and a monomer (b2) having an unsaturated double bond and a polar group are polymerized. It is preferable to use a prepared copolymer. As the polymerization method, for example, various polymerization methods such as a solution polymerization method, a dispersion polymerization method, a suspension polymerization method, and an emulsion polymerization method can be employed.

  In the copolymer obtained by polymerizing the polymerization component containing the (meth) acrylic monomer (b1) and the monomer (b2) having an unsaturated double bond and a polar group, the mixing ratio of both components in the polymerization component is That is, the mass ratio of b1 / b2 is preferably in the range of 10/90 to 99/1. If it sets to such a range, the fine unevenness | corrugation of a coating film can fully be expressed and the antiblocking property of a coating film can be improved more. Among these, the mass ratio of b1 / b2 is more preferably in the range of 25/75 to 85/15, and particularly preferably in the range of 30/70 to 80/20.

 In a copolymer obtained by polymerizing a polymerization component containing the styrene monomer (having no polar group) (c1) and a monomer (b2) having an unsaturated double bond and a polar group, The mixing ratio, that is, the mass ratio of c1 / b2 is preferably in the range of 10/90 to 99/1. If it sets to such a range, the fine unevenness | corrugation of a coating film can fully be expressed and the antiblocking property of a coating film can be improved more. Among them, the mass ratio of c1 / b2 is more preferably in the range of 25/75 to 85/15, and particularly preferably in the range of 30/70 to 80/20.

  In a copolymer obtained by polymerizing a polymerization component containing the acrylic monomer (having no polar group) (b1) and a styrene monomer (having no polar group) (c1), the mixing ratio of both components in the polymerization component That is, the mass ratio of b1 / c1 is preferably in the range of 1/99 to 99/1. If it sets to such a range, the fine unevenness | corrugation of a coating film can fully be expressed and the antiblocking property of a coating film can be improved more. Among these, the mass ratio of b1 / c1 is more preferably in the range of 20/80 to 80/20.

  A polymerization component containing the acrylic monomer (having no polar group) (b1) and a styrene monomer (having no polar group) (c1), and a monomer (b2) having an unsaturated double bond and a polar group In the polymerized copolymer, the mixing ratio of both components in the polymerization component, that is, the mass ratio of b1 + c1 / b2 is preferably in the range of 10/90 to 99/1. If it sets to such a range, the fine unevenness | corrugation of a coating film can fully be expressed and the antiblocking property of a coating film can be improved more. Especially, it is more preferable that the mass ratio of b1 + c1 / b2 is in a range of 25/75 to 85/15, and a particularly preferable range is 30/70 to 80/20.

  The (meth) acrylic monomer (having no polar group) (b1) is not particularly limited, and examples thereof include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, Those having a linear or branched alkyl group such as propyl (meth) acrylate, butyl (meth) acrylate and isobutyl (meth) acrylate, alicyclic such as cyclohexyl (meth) acrylate and methylcyclohexyl (meth) acrylate Examples thereof include those having a hydrocarbon group, those having a polycyclic hydrocarbon group such as boronyl (meth) acrylate, isobornyl (meth) acrylate, and the like. Of these, methyl (meth) acrylate is most preferred.

  The styrenic monomer (having no polar group) (c1) is not particularly limited, and examples thereof include styrene, divinylbenzene, o-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, Examples include o-ethyl styrene, p-ethyl styrene, 2,4-diethyl styrene, o-chloro styrene, p-chloro styrene, α-methyl styrene, 2-vinyl naphthalene, α-methyl-2-vinyl naphthalene. Of these, styrene is most preferred.

  As the monomer (b2) having an unsaturated double bond and a polar group, for example, a benzophenone-based monomer, a benzophenolate-based monomer, a benzotriazole-based monomer, and a hindered amine-based monomer are preferable, although there is no particular restriction on the basic structure. is there.

  The benzophenone-based monomer is not particularly limited. For example, 21-hydroxy-4-1- (3-1 methacryloxy-2-1-hydroxypropoxy) benzophenone, 2-hydroxy-4-1 (31-acryloxy-2-1-hydroxy). Propoxy) benzophenone, 2,2'-dihydroxy-4 (3 methacryloxy-2 1hydroxypropoxy) benzophenone, 2,2'-hydroxy-4-1 (3 acryloxy-2 1hydroxypropoxy) benzophenone, 2 (N Monomethacryloyl) aminobenzophenone and the like.

  Although it does not specifically limit as said benzotriazole type monomer, For example, 2 1 [2 '1 hydroxy-5' 1 (methacryloyloxymethyl) phenyl] 1 2H 1 benzotriazole, 2 1 [2 '1 hydroxy-5] 'One (methacryloyloxyethyl) phenyl] 1 2H monobenzotriazole, 2 [2' monohydroxy-5 'one (methacryloyloxypropyl) phenyl] 1 2H one benzotriazole, two [2' monohydroxy-5 'one (methacryloyl) Oxyhexyl) phenyl] 1 2H monobenzotriazole, 2 1 [2 '1 hydroxy-3' 1 tert 1 butyl 5 '1 (methacryloyloxyethyl) phenyl] 1 2H 1 benzotriazole, 2 1 [2' 1 hydroxy-5 '1 tert-butyl-3'-one (methacryloyl Oxyethyl) phenyl] 1 2H 1 benzotriazole, 2 1 [2 '1 hydroxy-5' 1 (methacryloyloxyethyl) phenyl] 1 5 chloro-2H 1 benzotriazole, 2 1 [2 '1 hydroxy 5' 1 (methacryloyloxyethyl) ) Phenyl] 15-methoxy-2H-benzotriazole, 2- [2'-hydroxy-5'-one (methacryloyloxyethyl) phenyl] -15-cyano-2H-benzotriazole, 2- [27-hydroxy-5'-one (methacryloyloxy) Ethyl) phenyl] -1-5-tert-butyl-2H-benzotriazole, 2- [2′-hydroxy-5 ′-((methacryloyloxyethyl) phenyl] -15-nitro-2H-benzotriazole, and the like.

  The hindered amine monomer is not particularly limited. For example, 4 (meth) acryloyloxy-2,2,6,6tetramethylpiperidine, 4 (meth) acryloylamino-2,2,6 6-tetramethylpiperidine, 4-1- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4- (meth) acryloylamino-1,2,2,6,6-pentamethylpiperidine, 4-Cyano-4-1- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine, 4-crotonoylamino-2,2, 6,6 monotetramethylpiperidine, 1 (meth) acryloyl 4 1 (meth) acryloylamino-2,2,6,6 1 tetra Tilpiperidine, 1 (meth) acryloyl 4 cyano-4 1 (meth) acryloylamino-2,2,6,6 tetratetrapiperidine, 1 crotonoyl 4 1crotonoyloxy-2,2,6,6 tetramethyl And piperidine.

  In addition, as the monomer (b2) having an unsaturated double bond and a polar group, a dimethyl sulfate monomer or a chlorine monomer known as an antistatic agent having an unsaturated double bond is also suitable.

  The photopolymerization initiator is not particularly limited. For example, benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, benzoin alkyl ethers, benzophenone, and aromatic ketones such as benzoylbenzoic acid. , Α-dicarbonyls such as benzyl, benzyl ketals such as benzyldimethyl ketal and benzyldiethyl ketal, acetophenone, 11 (41-dodecylphenyl) 21-hydroxy-2-1-methylpropane-11-one, 11-hydroxycyclohexylphenyl Ketone, 21-hydroxy-2 1-methyl-1 1-phenyl-1 1-propane- 1-one, 1 1 (4 1-isopropylphenyl) 1 2 1-hydroxy-2 1-methyl-propane-1 1-on, 2 1-methyl-1 1 [4 (Methylthio) phenyl] acetophenones such as 1 21 morpholinopropanone-1, anthraquinones such as 2 1 methyl anthraquinone, 2 1 ethyl anthraquinone, 2 tert 1 butyl anthraquinone, 2,4 1 dimethyl thioxanthone, 2 1 isopropyl thioxanthone Thioxanthones such as 2,4-diisopropylthioxanthone, α-acyloximes such as 1-phenyl-1,2-propanedione-21- (o-ethoxycarbonyl) oxime, ethyl p-dimethylaminobenzoate, p-dimethylaminobenzoate And amines such as isoamyl acid. Of these, acetophenones such as 21hydroxy-21-methyl-11-phenyl-11-propan-11-one, and aromatic ketones such as benzophenone are particularly suitable.

  Various additives such as an ultraviolet absorber, a light stabilizer, and a surface conditioner can be appropriately added to the ultraviolet curable paint of the present invention as necessary.

  Examples of the ultraviolet absorber include benzotriazole-based and hydroxyphenyltriazine-based compounds. The addition amount is 10 parts by mass or less, preferably 2 to 4 parts by mass with respect to 100 parts by mass of the ultraviolet curable paint.

  Examples of the light stabilizer include hindered amine compounds. The addition amount is 2 parts by mass or less, preferably 1 part by mass or less with respect to 100 parts by mass of the ultraviolet curable paint.

  The surface conditioner imparts wettability and uniformity to the base material of the coating film, smoothness and slipperiness of the coating film surface, and is typically a silicone type or acrylic copolymer type. However, a silicone type is particularly preferable. Examples of the silicone-based surface conditioner include polydimethylsiloxane and modified silicone obtained by modifying polydimethylsiloxane. Furthermore, examples of the modified silicone include polyether-modified products, alkyl-modified products, and polyester-modified products. Among these, polyether-modified products are most preferable.

  The ultraviolet curable paint of the present invention is, for example, diluted with an appropriate solvent with respect to the substrate surface made of various transparent plastic materials that require surface wear resistance, anti-blocking properties, etc. It is applied using various coating means such as roll coater, gravure coater, flow coater, spray coater, curtain flow coater, dip coater, slit die coater, etc. By irradiating and curing, a coating layer (such as a hard coat layer) having fine irregularities can be formed on the substrate surface.

  The coating film thickness at the time of coating is preferably 1 to 30 μm as a dry coating film, and if it is thicker than 30 μm, it is not preferable because adhesion to a substrate is lowered. In addition, it is desirable to raise the temperature of the substrate and the atmosphere when the solvent component is evaporated. For the ultraviolet irradiation, a general electroded or electrodeless high-pressure ultraviolet lamp or metal halide lamp can be used.

  The material of the base material to be coated is not particularly limited, but for example, a transparent plastic sheet for use in human protective equipment such as sports goggles, helmet shield, windshield, safety glasses, and safety shield. For example, polymethylmethacrylate, polyethylene terephthalate, polyvinyl chloride, etc. are preferably used. Also used for precision devices such as display covers, lenses, and sensor covers for various displays and instruments, housings such as partitions and showcases in houses and stores. Polycarbonate resin is suitable for rigid transparent plastic moldings used for installation purposes, transportation-related uses such as partitions and shelves, instrument covers, and windows in automobiles and railway vehicles.

  Next, specific examples of the ultraviolet curable paint of the present invention will be described, but the present invention is not particularly limited to these examples. The components of the ultraviolet curable resin (A), (meth) acrylic polymer (B), styrene polymer (C), acrylic-styrene copolymer (D), and photopolymerization initiator used in the examples and comparative examples are ,It is as follows.

[Components of UV curable resin (A)]
Polyfunctional urethane acrylate oligomer X: aliphatic isocyanate-based 15 functional urethane acrylate oligomer having a number average molecular weight of 2300 (“U-15HA” manufactured by Shin-Nakamura Chemical Co., Ltd.)
Polyfunctional urethane acrylate oligomer Y: aliphatic isocyanate-based hexafunctional urethane acrylate oligomer having a number average molecular weight of 1000 (“EB1290” manufactured by Daicel-Cytec Co., Ltd.)
Multifunctional urethane acrylate oligomer Z: Bifunctional urethane acrylate oligomer ("EB230" manufactured by Daicel-Cytec Corporation)
Bifunctional acrylate monomer: 1,6 monohexanediol diacrylate Monofunctional acrylate monomer: Isoboronyl acrylate

[(Meth) acrylic polymer (B1)]
In a 4-liter flask having a capacity of 1 liter equipped with a thermometer, a stirrer, an inert gas inlet, an air inlet and a reflux condenser, 80 parts by mass of methyl methacrylate as a (meth) acrylic monomer (b1), 18 parts by mass of 21 [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] 1-2H-benzobenzotriazole and 4-1-methacryloyloxy-1,2, as monomers (b2) having a saturated double bond and a polar group 2 parts by mass of 2,6,6 monopentamethylpiperidine and 120 parts by mass of propylene glycol monomethyl ether as a solvent were charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. After adding dropwise over 2 hours a mixture of 0.5 parts by mass of tert-butyl peroxy-2 monoethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator to this charged product, the mixture was further heated at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour to obtain a 40% by mass solution of (meth) acrylic polymer (B1) having a polar group in the side chain.

[(Meth) acrylic polymer (B2)]
In a 4-liter flask having a capacity of 1 liter equipped with a thermometer, a stirrer, an inert gas inlet, an air inlet and a reflux condenser, 80 parts by mass of methyl methacrylate as a (meth) acrylic monomer (b1), 20 parts by mass of 21 [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] 1-2H-benzotriazole as a monomer (b2) having a saturated double bond and a polar group, and propylene glycol monomethyl ether 120 as a solvent A mass part was charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. A 40% by mass solution of the (meth) acrylic polymer (B2) having a polar group in the side chain was obtained in the same manner as described above for this charged product.

[(Meth) acrylic polymer (B3)]
In a 4-liter flask having a capacity of 1 liter equipped with a thermometer, a stirrer, an inert gas inlet, an air inlet and a reflux condenser, 80 parts by mass of methyl methacrylate as a (meth) acrylic monomer (b1), Charged 20 parts by mass of 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine as a monomer (b2) having a saturated double bond and a polar group, and 120 parts by mass of propylene glycol monomethyl ether as a solvent The mixture was heated to 90 ° C. with stirring under a nitrogen atmosphere. A 40% by mass solution of the (meth) acrylic polymer (B3) having a polar group in the side chain was obtained in the same manner as described above for the charged product.

[(Meth) acrylic polymer (B4)]
In a 4-liter flask having a capacity of 1 liter equipped with a thermometer, a stirrer, an inert gas inlet, an air inlet and a reflux condenser, 80 parts by mass of methyl methacrylate as a (meth) acrylic monomer (b1), 20 parts by mass of 21-hydroxy-4-1 (3 methacryloxy-2 1-hydroxypropoxy) benzophenone as a monomer (b2) having a saturated double bond and a polar group, and 120 parts by mass of propylene glycol monomethyl ether as a solvent, Heat to 90 ° C. with stirring under a nitrogen atmosphere. A 40% by mass solution of the (meth) acrylic polymer (B3) having a polar group in the side chain was obtained in the same manner as described above for the charged product.

[(Meth) acrylic polymer (B5)]
In a 4-liter flask having a capacity of 1 liter equipped with a thermometer, a stirrer, an inert gas inlet, an air inlet and a reflux condenser, 80 parts by mass of methyl methacrylate as a (meth) acrylic monomer (b1), 0.5 part by mass of 2 [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] 1-2H-benzobenzotriazole as monomer (b2) having a saturated double bond and a polar group, and propylene glycol monomethyl as a solvent 120 parts by mass of ether was charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. After adding dropwise over 2 hours a mixture of 0.5 parts by mass of tert-butyl peroxy-2 monoethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator to this charged product, the mixture was further heated at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour to obtain a 40% by mass solution of the (meth) acrylic polymer (B5) having a polar group in the side chain.

[Styrene polymer (C1)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 80 parts by mass of styrene as the styrenic polymer (c1), and an unsaturated double bond And as a monomer (b2) having a polar group, 18 parts by mass of 2 [1'-hydroxy-5 '-((methacryloyloxyethyl) phenyl] -1 2H-benzobenzotriazole and 4'-methacryloyloxy-1,2,2,6 6 2 parts by mass of pentamethylpiperidine and 120 parts by mass of propylene glycol monomethyl ether as a solvent were charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. After adding dropwise over 2 hours a mixture of 0.5 parts by mass of tert-butyl peroxy-2 monoethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator to this charged product, the mixture was further heated at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour to obtain a 40% by mass solution of the styrene polymer (C1) having a polar group in the side chain.

[Styrene polymer (C2)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 80 parts by mass of styrene as the styrenic polymer (c1), and an unsaturated double bond And 20 parts by mass of 2 [mono-hydroxy-5 '-(methacryloyloxyethyl) phenyl] 2H-benzotriazole as a monomer (b2) having a polar group and 120 parts by mass of propylene glycol monomethyl ether as a solvent The mixture was heated to 90 ° C. while stirring under a nitrogen atmosphere. In the same manner as described above, a 40% by mass solution of a styrene polymer (C2) having a polar group in the side chain was obtained for this charged product.

[Styrene polymer (C3)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 80 parts by mass of styrene as the styrenic polymer (c1), and an unsaturated double bond And 20 parts by mass of 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine as a monomer (b2) having a polar group and 120 parts by mass of propylene glycol monomethyl ether as a solvent, and under a nitrogen atmosphere And heated to 90 ° C. with stirring. A 40% by mass solution of a styrene polymer (C3) having a polar group in the side chain was obtained in the same manner as described above for this charged product.

[Styrene polymer (C4)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 80 parts by mass of styrene as the styrenic polymer (c1), and an unsaturated double bond And 20 parts by mass of 2-hydroxy-4-one (3-1 methacryloxy-2-hydroxypropoxy) benzophenone as a monomer (b2) having a polar group and 120 parts by mass of propylene glycol monomethyl ether as a solvent, Heat to 90 ° C. with stirring. A 40% by mass solution of a styrene polymer (C4) having a polar group in the side chain was obtained in the same manner as described above with respect to this charged product.

[Styrene polymer (C5)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 80 parts by mass of styrene as the styrenic polymer (c1), and an unsaturated double bond And 0.5 part by mass of 2 [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl] 1 2H-benzotriazole as a monomer (b2) having a polar group, and 120 parts by mass of propylene glycol monomethyl ether as a solvent Was heated to 90 ° C. while stirring under a nitrogen atmosphere. A mixture of 0.5 parts by mass of t-butyl peroxy-2 monoethyl hexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator was added dropwise to the charged product over 2 hours, and then at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour to obtain a 40% by mass solution of a styrene polymer (C5) having a polar group in the side chain.

[Acrylic-styrene copolymer (D1)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 40 parts by mass of methyl methacrylate as (meth) acrylic monomer (b1) and styrene 40 parts by mass of styrene as the polymer (c1) and 21 [2'-hydroxy-5 '-((methacryloyloxyethyl) phenyl] 1-2H-benzotriazole as the monomer (b2) having an unsaturated double bond and a polar group 18 parts by mass and 4 parts of methacryloyloxy-1,2,2,6,6,1 part of pentamethylpiperidine and 120 parts by weight of propylene glycol monomethyl ether as a solvent were charged and stirred at 90 ° C. under a nitrogen atmosphere. Heated to. To this charged product, a mixture of 0.5 parts by mass of tert-butyl peroxy-2-ethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator was added dropwise over 2 hours, and then at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour to obtain a 40% by mass solution of an acrylic-styrene copolymer (D1) having a polar group in the side chain.

[Acrylic-styrene copolymer (D2)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 40 parts by mass of methyl methacrylate as (meth) acrylic monomer (b1) and styrene 40 parts by mass of styrene as the polymer (c1) and 21 [2'-hydroxy-5 '-((methacryloyloxyethyl) phenyl] 1-2H-benzotriazole 20 as the monomer (b2) having an unsaturated double bond and a polar group Part by mass and 120 parts by mass of propylene glycol monomethyl ether as a solvent were charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. A 40% by mass solution of an acrylic-styrene copolymer (D2) having a polar group in the side chain was obtained in the same manner as described above for this charged product.

[Acrylic-styrene copolymer (D3)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 40 parts by mass of methyl methacrylate as (meth) acrylic monomer (b1) and styrene 40 parts by mass of styrene as the polymer (c1) and 20 parts by mass of 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine as the monomer (b2) having an unsaturated double bond and a polar group Then, 120 parts by mass of propylene glycol monomethyl ether as a solvent was charged and heated to 90 ° C. with stirring under a nitrogen atmosphere. A 40% by mass solution of an acrylic-styrene copolymer (D3) having a polar group in the side chain was obtained in the same manner as described above for the charged product.

[Acrylic-styrene copolymer (D4)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 40 parts by mass of methyl methacrylate as (meth) acrylic monomer (b1) and styrene 40 parts by mass of styrene as the polymer (c1) and 20 parts by mass of 2-hydroxy-4-1- (3-1 methacryloxy-2-hydroxypropoxy) benzophenone as the monomer (b2) having an unsaturated double bond and a polar group, 120 parts by mass of propylene glycol monomethyl ether as a solvent was charged and heated to 90 ° C. with stirring in a nitrogen atmosphere. A 40% by mass solution of an acrylic-styrene copolymer (D4) having a polar group in the side chain was obtained in the same manner as described above for this charged product.

[Acrylic-styrene copolymer (D5)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 40 parts by mass of methyl methacrylate as (meth) acrylic monomer (b1) and styrene 40 parts by mass of styrene as the polymer (c1) and 21 [2'-hydroxy-5 '-((methacryloyloxyethyl) phenyl] 1-2H-benzotriazole as the monomer (b2) having an unsaturated double bond and a polar group 0.5 part by mass and 120 parts by mass of propylene glycol monomethyl ether as a solvent were charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. After adding dropwise over 2 hours a mixture of 0.5 parts by mass of tert-butyl peroxy-2 monoethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator to this charged product, the mixture was further heated at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour to obtain a 40% by mass solution of an acrylic-styrene copolymer (D5) having a polar group in the side chain.

[(Meth) acrylic polymer (E)]
In a 4-liter flask having a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 100 parts by mass of methyl methacrylate as a (meth) acrylic monomer (b1) and a solvent 120 parts by weight of propylene glycol monomethyl ether was charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. After adding dropwise over 2 hours a mixture of 0.5 parts by mass of tert-butyl peroxy-2 monoethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator to this charged product, the mixture was further heated at 90 ° C. Heated for 2 hours. Thereafter, the temperature is raised to 120 ° C. and kept at 120 ° C. for 1 hour, whereby 40% of the (meth) acrylic polymer (E) comprising a homopolymer of methyl methacrylate (having no polar group in the side chain). A solution was obtained.

[Styrene polymer (F)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 100 parts by mass of styrene as the styrenic polymer (c1) and propylene glycol as the solvent 120 parts by mass of monomethyl ether was charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. After adding dropwise over 2 hours a mixture of 0.5 parts by mass of tert-butyl peroxy-2 monoethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator to this charged product, the mixture was further heated at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour to obtain a 40% solution of a styrene polymer (F) composed of a styrene homopolymer (having no polar group in the side chain). .

[[Acrylic-styrene copolymer (G)]
In a four-liter flask with a capacity of 1 liter equipped with a thermometer, stirrer, inert gas inlet, air inlet and reflux condenser, 50 parts by mass of methyl methacrylate as a (meth) acrylic monomer (b1) and styrene 50 parts by mass of styrene as the polymer (c1) and 120 parts by mass of propylene glycol monomethyl ether as a solvent were charged and heated to 90 ° C. while stirring in a nitrogen atmosphere. After adding dropwise over 2 hours a mixture of 0.5 parts by mass of tert-butyl peroxy-2 monoethylhexanoate and 30 parts by mass of propylene glycol monomethyl ether as a polymerization initiator to this charged product, the mixture was further heated at 90 ° C. Heated for 2 hours. Thereafter, the temperature was raised to 120 ° C. and kept at 120 ° C. for 1 hour, whereby 40% of the acrylic-styrene copolymer (G) comprising a copolymer of methyl methacrylate and styrene (having no polar group in the side chain). A solution was obtained.

[Photopolymerization initiator]
11. Monohydroxycyclohexyl phenyl ketone (“Irgacure 184” manufactured by Ciba Specialty Chemicals).

It shows to Tables 1-3 about the mixing | blending of an Example and a comparative example.

<Example 1>
After mixing the ultraviolet curable resin (A) and the (meth) acrylic polymer (B) having a polar group in the side chain at a mass ratio of 99.5 / 0.5, a polar diluent solvent (methoxypropanol, methanol and isopropyl Diluted with an alcohol mixed solvent) so that the total amount of each component (ultraviolet curable resin, (meth) acrylic polymer, photopolymerization initiator, inorganic filler) is 20% by mass, and ultraviolet curable paint Got. At this time, a photopolymerization initiator (Irgacure 184) is previously dissolved in isopropyl alcohol, and 100 parts by mass of solid content (ultraviolet curable resin, (meth) acrylic polymer, photopolymerization initiator, inorganic filler). The photopolymerization initiator was added as part of the polar dilution solvent (mixed solvent) so that the photopolymerization initiator was in a proportion of 4 parts by mass. In addition, the description of the numerical value of the mass part in Tables 1-3 shows the mass part in solid content.

  Next, after applying the ultraviolet curable coating material to one side of a transparent polycarbonate sheet having a thickness of 1.5 mm (“Polyca Ace” manufactured by Sumitomo Bakelite Co., Ltd.) using a metal bar coater, the coating is heated in a hot air circulation oven. Heating at 10 ° C. for 10 minutes and drying were performed. Thereafter, a hard coat layer having a thickness of 10 μm was formed by irradiating the coating film with ultraviolet rays using a 160 W / cm metal halide lamp (manufactured by USHIO INC.). The ultraviolet irradiation was performed under the conditions of a distance between the metal halide lamp and the coating film of 15 cm and a transfer conveyor speed of 1.5 m / min.

<Example 2>
A hard coat layer is formed in the same manner as in Example 1 except that the ultraviolet curable resin (A) and the (meth) acrylic polymer (B) having a polar group in the side chain are mixed at a mass ratio of 60/40. did.

<Example 3>
A hard coat layer was formed by the same method as in Example 1 except that the average number of functional groups of the components contained in the ultraviolet curable resin (A) was 2.0.

<Example 4>
A hard coat layer was formed in the same manner as in Example 1 except that the average number of functional groups of the components contained in the ultraviolet curable resin (A) was 8.0.

<Examples 5 and 6>
The hard coating was carried out in the same manner as in Example 1 except that the mass ratio of the ultraviolet curable resin (A) and the (meth) acrylic polymer (B) having a polar group in the side chain was most preferably 80/20. A layer was formed.

<Example 7>
In the (meth) acrylic polymer (B) having a polar group in the side chain, as the monomer (b2) having an unsaturated double bond and a polar group, 2 [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl A hard coat layer was formed in the same manner as in Example 6 except that 12H monobenzotriazole was used.

<Example 8>
In the (meth) acrylic polymer (B) having a polar group in the side chain, as a monomer (b2) having an unsaturated double bond and a polar group, 4-methacryloyloxy-1,2,2,6,6 A hard coat layer was formed in the same manner as in Example 6 except that methylpiperidine was used.

<Example 9>
In the (meth) acrylic polymer (B) having a polar group in the side chain, as a monomer (b2) having an unsaturated double bond and a polar group, 2-hydroxy-4 one (3 methacryloxy-2 monohydroxypropoxy) A hard coat layer was formed in the same manner as in Example 6 except that benzophenone was used.

<Example 10>
In the (meth) acrylic polymer (B) having a polar group in the side chain, as the monomer (b2) having an unsaturated double bond and a polar group, 2 [2'-hydroxy-5 '-(methacryloyloxyethyl) phenyl A hard coat layer was formed in the same manner as in Example 6 except that 0.5 part by mass of 1 2H monobenzotriazole was used.

<Example 11>
The same procedure as in Example 6 was used, except that a styrene polymer (C 1 ) having a polar group in the side chain was used instead of the (meth) acrylic polymer (B) having a polar group in the side chain. A hard coat layer was formed.

<Example 12>
The same procedure as in Example 6 except that instead of the (meth) acrylic polymer (B) having a polar group in the side chain, an acrylic-styrene copolymer (D 1 ) having a polar group in the side chain was used. Thus, a hard coat layer was formed.

<Example 13>
A hard coat was produced in the same manner as in Example 6 except that a (meth) acrylic polymer (B) having a polar group in the side chain and a styrene polymer (C 1 ) having a polar group in the side chain were used. A layer was formed.

<Example 14>
Hardness was obtained in the same manner as in Example 6 except that the (meth) acrylic polymer (B) having a polar group in the side chain and the acrylic-styrene copolymer (D 1 ) having a polar group in the side chain were used. A coat layer was formed.

<Example 15>
Instead of the (meth) acrylic polymer (B) having a polar group in the side chain, a styrene polymer (C 1 ) having a polar group in the side chain and an acrylic-styrene copolymer having a polar group in the side chain ( A hard coat layer was formed in the same manner as in Example 6 except that D 1 ) was used.

<Example 16>
Along with the (meth) acrylic polymer (B) having a polar group in the side chain, a styrene polymer (C 1 ) having a polar group in the side chain and an acrylic-styrene copolymer having a polar group in the side chain (D 1 ) Was used to form a hard coat layer by the same method as in Example 6.

<Comparative Example 1>
After mixing the ultraviolet curable resin (A) and the (meth) acrylic polymer (B) having a polar group in the side chain at a mass ratio of 99.7 / 0.3, a polar diluent solvent (methoxypropanol, methanol and isopropyl Diluted with an alcohol mixed solvent) so that the total amount of each component (ultraviolet curable resin, (meth) acrylic polymer, photopolymerization initiator, inorganic filler) is 20% by mass, and ultraviolet curable paint Got. At this time, a photopolymerization initiator (Irgacure 184) is previously dissolved in isopropyl alcohol, and 100 parts by mass of solid content (ultraviolet curable resin, (meth) acrylic polymer, photopolymerization initiator, inorganic filler). The photopolymerization initiator was added as part of the polar dilution solvent (mixed solvent) so that the photopolymerization initiator was in a proportion of 4 parts by mass. In addition, the description of the numerical value of the mass part in Tables 1-3 shows the mass part in solid content.

  Next, the UV curable paint was applied to one side of a 1.5 mm thick transparent polycarbonate sheet ("Polyca Ace" manufactured by Sumitomo Bakelite Co., Ltd.) using a metal bar coater, and then heated at 80 ° C in a hot air circulating oven. And then dried for 10 minutes. Thereafter, a hard coat layer having a thickness of 10 μm was formed by irradiating the coating film with ultraviolet rays using a 160 W / cm metal halide lamp (manufactured by USHIO INC.). The ultraviolet irradiation was performed under the conditions of a distance between the metal halide lamp and the coating film of 15 cm and a transfer conveyor speed of 1.5 m / min.

<Comparative example 2>
A hard coat layer was formed in the same manner as in Comparative Example 1 except that the blending ratio of the (meth) acrylic polymer (B) having a polar group in the side chain was 45, which was larger than the upper limit.

<Comparative Example 3>
A hard coat layer was formed in the same manner as in Comparative Example 1 except that the average number of functional groups of the components contained in the ultraviolet curable resin (A) was less than 1.8 lower limit.

<Comparative example 4>
A hard coat layer was formed in the same manner as in Comparative Example 1 except that the average number of functional groups of the components contained in the ultraviolet curable resin (A) was 8.3, which was larger than the upper limit.

<Comparative Example 5>
Instead of the (meth) acrylic polymer (B) having a polar group in the side chain, a (meth) acrylic polymer (E) having no polar group in the side chain is used, and an ultraviolet curable resin (A) and A hard coat layer was formed in the same manner as in Comparative Example 1 except that the mass ratio of the (meth) acrylic polymer (E) having no polar group in the side chain was mixed at 80/20.

<Comparative Example 6>
Hardening was performed in the same manner as in Comparative Example 5 except that a styrene polymer (F) having no polar group in the side chain was used instead of the (meth) acrylic polymer (B) having a polar group in the side chain. A coat layer was formed.

<Comparative Example 7>
The same procedure as in Comparative Example 5 was used except that an acrylic-styrene copolymer (G) having no polar group in the side chain was used instead of the (meth) acrylic polymer (B) having a polar group in the side chain. A hard coat layer was formed.

<Comparative Example 8>
The average functional group number of the component contained in the ultraviolet curable resin (A) is 2.0, and instead of the (meth) acrylic polymer (B1), amorphous silica spherical particles (manufactured by Nippon Shokubai Co., Ltd.) are used as the inorganic filler. A hard coat layer was formed in the same manner as in Comparative Example 1 except that “Seahoster KE-P150”) was used.

  The anti-blocking property, abrasion resistance, transparency and coating film adhesion of the hard coat layer of each polycarbonate sheet formed as described above were evaluated based on the following evaluation methods. These evaluation results are shown in Tables 1-3.

<Anti-blocking property>
Place the sample (polycarbonate sheet) on the polycarbonate plate so that the hard coat layer is on the bottom, and press the sample with your finger with a force of about 500 g / cm2. evaluated.
“◯”: no blocking at all and “Δ” excellent in anti-blocking property: a little blocking, but “x” at a practically usable level—remarkably blocking.

<Transparency>
The haze ratio (%) of the polycarbonate sheet (including the hard coat layer) was measured, and the transparency was evaluated according to the following criteria.
“○”: Excellent transparency (haze ratio is less than 3%)
“×”: Transparency is insufficient in practice (the haze ratio is 3% or more).

<Abrasion resistance>
In accordance with ASTM D1044, after performing a taper type abrasion test (CS10F wear wheel, load 500 g, 100 rotations) on the surface of the hard coat layer, the haze ratio H2 (%) of the polycarbonate sheet (including the hard coat layer) ) And the amount of change (change value) of the haze ratio H1 (%) of the polycarbonate sheet (including the hard coat layer) before the wear test. Change amount of haze ratio before and after abrasion test ΔH (%) = H2−H1
The abrasion resistance was evaluated from the amount of change ΔH according to the following criteria.
“◎”: very good wear resistance (change in haze ratio ΔH is less than 5%)
“◯”: Excellent wear resistance (change value of haze ratio ΔH is 5% or more and less than 7%)
“△”: Wear resistance is slightly insufficient for practical use (change in haze ratio ΔH is 7% or more and less than 10%)
“×”: Insufficient wear resistance in practice (change in haze ratio ΔH is 10% or more)

<Adhesiveness of coating film>
After immersing the sample (polycarbonate sheet) in boiling water for 60 minutes, wipe off the moisture and dry at room temperature for 2 hours or more, and then perform a cross-cut tape peeling test according to JIS K5600-5-6-1999. The adhesion was evaluated according to the following criteria.
“Good”: Excellent adhesion (25 out of 25 squares did not peel)
“X”: Poor adhesion and impractical (1 out of 25 squares peeled).

  The cured coating film formed using the ultraviolet curable paint of the present invention is excellent in all of anti-blocking properties, abrasion resistance, transparency, and adhesion as is apparent from the results of Examples 1 to 16. It was found that it has extremely high performance for forming a hard coat layer of a transparent plastic material.

In contrast, in Comparative Example 1 in which the content ratio of the (meth) acrylic polymer (B) having a polar group in the side chain was smaller than the specified range of the present invention, the antiblocking property was insufficient.
Further, in Comparative Example 2 in which the content ratio of the (meth) acrylic polymer (B) having a polar group in the side chain was larger than the specified range of the present invention, the adhesion of the coating film was inferior.
Moreover, in Comparative Examples 3 and 4 in which the average number of functional groups in the ultraviolet curable resin (A) deviates from the specified range of the present invention, the wear resistance was insufficient.
Moreover, the comparative example 5 which used the (meth) acrylic polymer which does not have a polar group in a side chain as a (meth) acrylic polymer, or the comparison which used the styrene polymer which does not have a polar group in a side chain as a styrene polymer In Example 6 or Comparative Example 7 using an acrylic-styrene copolymer having no polar group in the side chain as the acrylic-styrene copolymer, the antiblocking property was insufficient. In Comparative Example 8 using spherical particles of inorganic filler instead of the (meth) acrylic polymer, the transparency was insufficient.

Claims (7)

It contains a polyfunctional urethane (meth) acrylate oligomer, and at least one (meth) acrylic monomer component selected from the group consisting of a polyfunctional (meth) acrylate monomer and a monofunctional (meth) acrylate monomer. An ultraviolet curable resin (A) having a base number of 1.9 to 8.2;
Selected from (meth) acrylic polymer (B) having compatibility with the ultraviolet curable resin (A) and having a polar group in the side chain, styrene polymer (C) and acrylic-styrene copolymer (D) At least one polymer selected from
A photopolymerization initiator;
A resin composition containing
The mass ratio of the polyfunctional urethane (meth) acrylate oligomer (a1) and the (meth) acrylic monomer component (a2) used in the ultraviolet curable resin (A) is 90/10. ~ 70/30,
The mass ratio of at least one polymer selected from (meth) acrylic polymer (B), styrene polymer (C) and acrylic-styrene copolymer (D) to the ultraviolet curable resin (A) is 60/40. 99.5 / 0.5 der is, the polar group comprises a benzophenone group, a benzo phenolate groups, benzotriazole groups, at least one polar group selected from a hindered amine group, wherein the (meth) acrylic polymer (B), a styrene-based polymer (C) and acrylic - styrene copolymer (D) an ultraviolet curable coating material having a number average molecular weight and wherein the Dearuko 500-500000 of.   The (meth) acrylic polymer (B) is a (meth) acrylic copolymer obtained by polymerizing a polymerization component containing a (meth) acrylic monomer and a monomer having an unsaturated double bond and a polar group. The ultraviolet curable paint according to claim 1, comprising a coalescence. The styrene polymer (C), and a styrene monomer, an unsaturated double bond and claim 1 or 2 monomers and one in which polymer component containing contains a styrene-based copolymer formed by polymerization of having a polar group The ultraviolet curable paint described in 1. The acrylic-styrene copolymer (D) is an acrylic-styrene copolymer obtained by polymerizing a polymerization component containing a (meth) acrylic monomer, a styrene monomer, and a monomer having an unsaturated double bond and a polar group. The polymer composition according to any one of claims 1 to 3, comprising a polymer .
Item 1. The ultraviolet curable paint according to item 1 . The polyfunctional urethane (meth) acrylate oligomer is a polyfunctional urethane (meth) acrylate oligomer that is a reaction product of an isocyanate compound obtained by reacting a polyol and diisocyanate and a (meth) acrylate monomer having a hydroxyl group, The ultraviolet curable paint according to any one of claims 1 to 4, wherein the ultraviolet curable paint is contained.   A hard coat layer produced by applying and drying the ultraviolet curable paint according to any one of claims 1 to 5.   A transparent polycarbonate sheet on which the hard coat layer according to claim 6 is formed.