JP2011074351A - Resin composition and molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition that can give a coating film achieving toughness which prevents fracture, as well as high wear resistance, high hardness, and excellent in stainproof. <P>SOLUTION: The resin composition comprises total 100 pts.wt. of a polyfunctional (meth)acrylate monomer having at least 3 (meth)acryloyl groups and/or a polyfunctional acrylate oligomer, and an acrylic polymer having substantially no unsaturated group, and having a hydrophilic functional group, a weight-average molecular weight of 5,000-200,000 in an amount of 10 to 60 pts.wt. in terms of solid content, compounded in the composition, further comprising a perfluoropolyether acrylate compound and a photopolymerization initiator. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a resin composition having high wear resistance, hardness and toughness that is difficult to break, and also excellent in antifouling properties, and a molded article in which the resin composition is applied to a substrate.

  In recent years, active energy ray-curable coatings have been used in place of conventional thermosetting coatings in order to improve the surface hardness of casings, operation units, and plastic products such as optical films such as mobile phones and home appliances. Active energy ray-curable coatings are rapidly spreading compared to thermosetting coatings because they are fast-curing, have good productivity, can save energy, and have excellent wear resistance and hardness.

  However, the active energy ray-curable hard coat resin composition has a high degree of wear resistance and hardness, but also has a weak point that it is brittle and easily cracked. Therefore, attempts have been made to improve brittleness by adding high molecular weight urethane acrylate oligomers, acrylic polymers, etc. in addition to polyfunctional (meth) acrylates, and imparting flexibility, but the crosslinking density is reduced. Therefore, there has been a problem that the wear resistance and hardness are greatly reduced. Therefore, an active energy ray-curable hard coat resin composition that has toughness that is difficult to break, wear resistance, and hardness has been desired.

Patent Document 1 discloses a resin composition containing a polyfunctional (meth) acrylate and an acrylic polymer, but the wear resistance is not sufficient. Patent Document 2 discloses a resin composition containing a polyfunctional urethane (meth) acrylate and a (meth) acrylic copolymer resin, but the toughness is not sufficient.
JP-A-9-48934 JP 2006-316249 A

  Moreover, in the said use, since dirt, such as a fingerprint, is easy to adhere, the dirt which a fingerprint etc. are difficult to adhere, and the performance which can be easily wiped off is required when adhering.

  An object of the present invention is to provide a resin composition that has both toughness that is difficult to break, wear resistance, and hardness, and is useful as an active energy ray-curable hard coat resin composition, and a molded product in which the resin composition is applied to a substrate. It is. Moreover, another subject of this invention is providing the resin composition which is further excellent in antifouling property in addition to the said characteristic, and the molding in which this was apply | coated to the base material.

  In the present invention, the polyfunctional (meth) acrylate monomer and / or the polyfunctional acrylate oligomer has a total weight of 100 parts by weight and contains substantially no unsaturated group, has a hydrophilic functional group, and has a weight average molecular weight. The resin composition is characterized in that an acrylic polymer of 5,000 to 200,000 is blended in an amount of 10 to 60 parts by weight in terms of solid content. Preferably, the resin composition further contains a perfluoropolyether acrylate compound.

  The cured product of the resin composition of the present invention has high wear resistance, hardness and toughness that is difficult to break, and can be applied to an active energy ray-curable coating material that is excellent in productivity. Therefore, if a molded product obtained by applying the resin composition to a base material such as plastic is used for a housing or an operation unit of various devices, it is difficult to cause scratches or cracks due to dropping or contact. In addition, since the cured product of the resin composition of the present invention is excellent in antifouling property, dirt such as fingerprints is difficult to adhere and can be easily wiped off. Therefore, it is particularly suitable for portable devices such as mobile phones, portable music players, portable video players, portable televisions, cameras, videos, portable game machines, personal digital assistants, notebook computers, electronic notebooks, electronic dictionaries, etc. .

Hereinafter, the present invention will be described in detail.
In the present invention, a polyfunctional (meth) acrylate monomer and / or a polyfunctional acrylate oligomer is used. Examples of the polyfunctional acrylate monomer include 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, polyethylene glycol diacrylate, hydroxypivalate neopentyl glycol diacrylate, and dicyclopentanyl. Diacrylate, caprolactone-modified dicyclopentenyl diacrylate, ethylene oxide-modified phosphate diacrylate, allylated cyclohexyl diacrylate, isocyanurate diacrylate, trimethylolpropane triacrylate, dipentaerythritol triacrylate, propionic acid-modified dipentaerythritol triacrylate, Pentaerythritol triacrylate, propylene oxide modified trimethylolpro Down triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol pentaacrylate, propionic acid-modified dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, and caprolactone-modified dipentaerythritol hexaacrylate. Moreover, what oligomerized these can be used as the said polyfunctional acrylate oligomer. Polyfunctional methacrylate monomers include ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol di Methacrylate, 1,10-decanediol dimethacrylate, glycerin dimethacrylate, dimethylol-tricyclodecane dimethacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane trimethacrylate, etc. may be mentioned. You may mix and use.

  The acrylic polymer which does not contain an unsaturated group substantially and has a hydrophilic functional group and has a weight average molecular weight of 5,000 to 200,000 used in the present invention is an unsaturated monomer having a hydrophilic functional group. The polymer can be obtained by homopolymerization or copolymerization of an unsaturated monomer having a hydrophilic functional group and an unsaturated monomer not containing a hydrophilic functional group. The weight average molecular weight can be adjusted by the amount of the polymerization catalyst, the chain transfer agent, the type of solvent used, and the like.

  As unsaturated monomers having a hydrophilic functional group, (meth) acrylic acid having a carboxyl group, itaconic acid, fumaric acid, maleic acid, etc., 2-hydroxyethyl (meth) acrylate having a hydroxyl group, hydroxypropyl (meth) An acrylate etc. are mentioned. Examples of the unsaturated monomer that does not contain a hydrophilic functional group include styrene, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and methyl (meth) acrylate. When an acrylic polymer having no hydrophilic functional group is used, the abrasion resistance of the coating film of the blend is greatly reduced as compared with the case where an acrylic polymer containing a hydrophilic functional group is made into a paint.

  The weight average molecular weight of the acrylic polymer needs to be 5,000 to 200,000. When the weight average molecular weight is less than 5,000, the wear resistance is insufficient, and when the weight average molecular weight exceeds 200,000, the moldability and toughness including coating properties are insufficient. The acrylic polymer is blended in an amount of 10 to 60 parts by weight in solid content with respect to a total of 100 parts by weight of the polyfunctional (meth) acrylate monomer and / or polyfunctional acrylate oligomer. The shrinkage relaxation effect cannot be obtained and cracks occur. If it exceeds 60 parts by weight, the wear resistance and hardness are lowered.

When the acrylic polymer contains an unsaturated group, curing shrinkage due to the polyfunctional (meth) acrylate monomer and / or the polyfunctional acrylate oligomer cannot be sufficiently relaxed. Therefore, the acrylic polymer needs to be substantially free of unsaturated groups. Note that substantially not containing an unsaturated group means that an unsaturated group-containing compound is introduced into the acrylic polymer by a method such as reacting an unsaturated group-containing compound after polymerization of the acrylic polymer. When a partially unreacted unsaturated group remains when the acrylic polymer is polymerized, it is assumed that the unsaturated group is not substantially contained.

  By adding a perfluoropolyether acrylate compound to the resin composition of the present invention, antifouling property and fingerprint resistance can be imparted to the cured coating film. In the perfluoropolyether acrylate compound, one isocyanate group of triisocyanate is reacted with a perfluoropolyether compound containing a hydroxy group, and the remaining two isocyanate groups contain a hydroxy group (meth) acrylate monomer or ( It can be obtained by a method such as reacting a meth) acrylate oligomer. Perfluoropolyether acrylate compounds are commercially available, and examples thereof include OPTOOL DAC (manufactured by Daikin Industries, Ltd., trade name).

  The compounding amount of the perfluoropolyether acrylate compound is such that the polyfunctional (meth) acrylate monomer and / or the polyfunctional acrylate oligomer and the solid acrylic polymer having a hydrophilic functional group substantially free of unsaturated groups. The total solid content is preferably 0.03 to 5 parts by weight, more preferably 0.05 to 3 parts by weight, based on 100 parts by weight. By adding 0.03 part by weight or more, the antifouling property is remarkably exhibited, and by setting the content to 5 parts by weight or less, the hardness of the cured coating film can be maintained. Moreover, favorable antifouling property is acquired by the contact angle with respect to the water of a cured coating film being 90 degree | times and the contact angle with respect to an oleic acid being 50 degree | times or more by the mixing | blending of a perfluoro polyether compound.

  The resin composition of the present invention can be cured by irradiation with active energy rays such as an electron beam or ultraviolet rays, but can be cured with high sensitivity by adding a photopolymerization initiator. Examples of the photopolymerization initiator include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, benzophenone, 2-chlorobenzophenone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, Carbonyl compounds such as benzoin isopropyl ether, sulfur compounds such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, and tetramethylthiuram disulfide can be used. Commercially available products of these photopolymerization initiators include Irgacure 184, 369, 651, 500 (Ciba Specialty Chemicals, trade name), Lucirin LR8728 (BASF, trade name), Darocur 1116, 1173 (Merck, trade name) Name), Ubekrill P36 (manufactured by UCB, trade name) and the like.

  The base material of the molded product to which the resin composition of the present invention is applied is not particularly limited, but ABS, PC, acrylic, PS, MS, PBT, PPS, PET, TAC, etc., alone or in combination of two or more And various plastics.

  The method for applying the resin composition of the present invention on the substrate is not particularly limited, and known spray coating, dipping, roll coating, die coating, air knife coating, blade coating, spin coating, reverse coating, gravure coating, wire bar, etc. Or a printing method such as gravure printing, screen printing, offset printing, or ink jet printing. The thickness of the resin layer is preferably 1 μm to 40 μm. When the thickness of the resin layer is less than 1 μm, it is difficult to obtain sufficient hardness, and when it exceeds 40 μm, cracks are likely to occur.

  The resin composition used in the present invention includes various resins such as acrylic resins, urethane resins, styrene resins, phenolic resins, melamine resins, barium hydroxide, magnesium hydroxide, hydroxylated as necessary. In addition to inorganic fillers such as aluminum, silicon oxide, titanium oxide, calcium sulfate, barium sulfate, calcium carbonate, basic zinc carbonate, basic lead carbonate, silica sand, clay, talc, silica compound, titanium dioxide, silanes and titanates Coupling agents such as antibacterial agents, bactericides, preservatives, plasticizers, flow regulators, antistatic agents, thickeners, pH adjusters, surfactants, leveling regulators, antifoaming agents, color pigments, rust preventive pigments You may add compounding materials, such as. Moreover, you may add antioxidant and a ultraviolet absorber for the purpose of a weather resistance improvement. In addition, it is not preferable to use the above-mentioned compound containing an unsaturated group because problems such as cracks may occur in the coating film.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and demonstrated in detail about this invention, a specific example is shown and it does not specifically limit to these.

Synthesis of acrylic polymer 1 having a hydrophilic functional group and containing no unsaturated group Dilauroyl peroxide (manufactured by NOF Corporation, trade name Parroyl L) is added to 24 parts by weight of methyl ethyl ketone (MEK) (495 parts by weight). Heat at 30 ° C. for 30 minutes to dissolve, methacrylic acid 50 parts by weight, butyl acrylate 90 parts by weight, methyl methacrylate
A solution prepared by mixing 0 part by weight and 2.4 parts by weight of 4-methyl-2,4-diphenylpentene-1 (manufactured by NOF Corporation, trade name: NOFMER MSD) was added dropwise over 4 hours to polymerize with stirring. Thereafter, the mixture was further stirred at 80 ° C. for 2 hours to obtain an acrylic polymer 1 (solid content 35%, weight average molecular weight 6000) containing a hydrophilic functional group. In addition, GPC (gel permeation chromatography) was used for the weight average molecular weight measurement, and a polystyrene-based molecular weight was measured and calculated using a styrene divinylbenzene-based column in a THF developing solvent.

Synthesis of acrylic polymer 2 having a hydrophilic functional group and containing no unsaturated group 1.2 parts by weight of dilauroyl peroxide was added to 448 parts by weight of MEK and dissolved by heating at 70 ° C. for 30 minutes. A solution prepared by mixing parts by weight, 90 parts by weight of butyl acrylate, and 100 parts by weight of methyl methacrylate was added dropwise over 4 hours to perform stirring polymerization. Thereafter, the mixture was further stirred at 80 ° C. for 4 hours to obtain an acrylic polymer 2 (solid content 35%, weight average molecular weight 200000) containing a hydrophilic functional group.

Synthesis of acrylic polymer 3 having a hydrophilic functional group and containing no unsaturated group 24 parts by weight of dilauroyl peroxide is added to 513 parts by weight of MEK and heated at 70 ° C. for 30 minutes to dissolve, 50 parts by weight of methacrylic acid A solution prepared by mixing 90 parts by weight of butyl acrylate, 100 parts by weight of methyl methacrylate and 12 parts by weight of 4-methyl-2,4-diphenylpentene-1 was dropped and polymerized with stirring over 4 hours. Thereafter, the mixture was further stirred at 80 ° C. for 2 hours to obtain an acrylic polymer 3 (solid content 35%, weight average molecular weight 3000) containing a hydrophilic functional group.

  As acrylic polymer 4 containing a hydrophilic functional group and an unsaturated group, Cyclomer P ACA Z320 (manufactured by Daicel-Cytec Co., Ltd., trade name, solid content 38 to 40%, acid value 126 to 144 KOH mg / g, double A binding equivalent of 450) was used.

Synthesis of acrylic polymer 5 containing no hydrophilic functional group and unsaturated group 24 parts by weight of dilauroyl peroxide was added to 495 parts by weight of MEK and dissolved by heating at 70 ° C. for 30 minutes, 120 parts by weight of butyl acrylate, methyl methacrylate A solution in which 120 parts by weight and 2.4 parts by weight of 4-methyl-2,4-diphenylpentene-1 were mixed was dropped over 4 hours and polymerized with stirring. Thereafter, the mixture was further stirred at 80 ° C. for 2 hours to obtain an acrylic polymer 5 (solid content 35%, weight average molecular weight 20000) containing no hydrophilic functional group.

Example 1
100 parts by weight of dipentaerythritol pentaacrylate (manufactured by Sartomer, trade name SR399, solid content 100%), 28.6 parts by weight of acrylic polymer 1 (solid content 35%), Irgacure 184 (Ciba Specialty Chemical) as an initiator 5 parts by weight) was added, and MEK was added so that the solid content was 40%, to obtain a resin composition of Example 1.

Example 2
Mix 100 parts by weight of dipentaerythritol pentaacrylate, 171.4 parts by weight of acrylic polymer 1 (solid content 35%), 5 parts by weight of Irgacure 184 as an initiator, and add MEK to a solid content of 40%. The resin composition of Example 2 was obtained.

Example 3
Mix 100 parts by weight of dipentaerythritol pentaacrylate, 28.6 parts by weight of acrylic polymer 2 (solid content 35%), 5 parts by weight of Irgacure 184 as an initiator, and add MEK to a solid content of 40%. The resin composition of Example 3 was obtained.

Example 4
Mix 100 parts by weight of dipentaerythritol pentaacrylate, 171.4 parts by weight of acrylic polymer 2 (solid content 35%), 5 parts by weight of Irgacure 184 as an initiator, and add MEK to a solid content of 40%. The resin composition of Example 4 was obtained.

Example 5
100 parts by weight of dipentaerythritol pentaacrylate, 114.3 parts by weight of acrylic polymer 1 (solid content 35%), 5 parts by weight of Irgacure 184 as an initiator, and perfluoropolyether-modified urethane as a perfluoropolyether compound The resin composition of Example 5 was added by adding 0.35 parts by weight of OPTOOL DAC (produced by Daikin Industries, Ltd., solid content 20%, trade name), which is an acrylate oligomer, and further adding MEK so that the solid content was 40%. Obtained.

Example 6
A resin composition of Example 6 was obtained in the same manner as in Example 5 except that the amount of Optool DAC was changed to 21 parts by weight.

Comparative Example 1
Mix 100 parts by weight of dipentaerythritol pentaacrylate, 228.6 parts by weight of acrylic polymer 1 (solid content 35%), 5 parts by weight of Irgacure 184 as an initiator, and add MEK to a solid content of 40%. The resin composition of Comparative Example 1 was obtained.

Comparative Example 2
Mix 100 parts by weight of dipentaerythritol pentaacrylate, 114.3 parts by weight of acrylic polymer 3 (solid content 35%), 5 parts by weight of Irgacure 184 as an initiator, and add MEK to a solid content of 40%. The resin composition of Comparative Example 2 was obtained.

Comparative Example 3
Mix 100 parts by weight of dipentaerythritol pentaacrylate, 25.6 parts by weight of acrylic polymer 4 (solid content 39%), 5 parts by weight of Irgacure 184 as an initiator, and add MEK to a solid content of 40%. The resin composition of Comparative Example 3 was obtained.

Comparative Example 4
Mix 100 parts by weight of dipentaerythritol pentaacrylate, 171.4 parts by weight of acrylic polymer 5 (solid content 35%), 5 parts by weight of Irgacure 184 as an initiator, and add MEK to a solid content of 40%. The resin composition of Comparative Example 4 was obtained.

Test Evaluation Method Each resin composition prepared in Examples and Comparative Examples was sprayed on a PC board (1600, 5 cm × 10 cm × 2 mm thickness, manufactured by Takiron Co., Ltd.) and dried at 80 ° C. for 5 minutes to volatilize the solvent. And cured by irradiating with ultraviolet rays at 100 mW / cm ² and 800 mJ / cm ² using an electroded high-pressure mercury lamp (manufactured by Eye Graphics) to form a cured product layer having a thickness of 10 μm. It was evaluated with.

Measurement of crack resistance A heat cycle test was carried out using a test piece coated on PC. A thermostat with a temperature program function was used. After holding at 80 ° C. for 30 minutes, holding at −30 ° C. for 30 minutes was defined as one cycle, and this was performed for 10 cycles. After the test, the coating film surface was visually checked for cracks and evaluated as follows.
No crack ... ○, crack ... ×

Measurement of pencil hardness It was performed based on the provisions of JIS K 5600-5-4 (1999 edition). The measuring apparatus used was a pencil scratch coating film hardness tester (type P) manufactured by Toyo Seiki Seisakusho.

Measurement of abrasion resistance Using steel wool (trade name Bonster # 0000, manufactured by Nippon Steel Wool Co., Ltd.), a load of 500 g / cm ² was applied and the coating film was rubbed 10 times. It evaluated as follows from the way of entering a crack.
No scratch ... ◎
Less than 5 scratches ... ○
Scratches 5-10 ... △
More than 10 scratches ×

Measurement of contact angle Ion exchange water and oleic acid (manufactured by Kishida Chemical Co., Ltd.) were dropped on the surface of the cured coating film, and the contact angle was measured using a contact angle meter CA-X type (manufactured by Kyowa Interface Science Co., Ltd.).

Measurement of antifouling property A line was written on the surface of the cured coating film with a marking pen (trade name Magic Ink No. 700, manufactured by Teranishi Chemical Industry Co., Ltd.), and the ink remaining after wiping with a waste cloth was evaluated.
No ink residue ... ◎
With ink marks ... ×

Measurement of anti-fingerprint property A fingerprint was adhered to the surface of the cured coating film, wiped with a waste cloth, and the number of times of wiping until the fingerprint was completely invisible was recorded.

  As shown in Table 1, the specimens using the resin compositions of Examples 1 to 6 were excellent in wear resistance and hardness, and also had good toughness (crack resistance). Moreover, about Example 5 and 6 which mix | blended the perfluoro polyether acrylate compound, it became a result excellent also in antifouling property and fingerprint resistance. On the other hand, as shown in each comparative example, when the weight average molecular weight or blending ratio of the acrylic polymer is not suitable, when an acrylic polymer not containing a hydrophilic functional group is used, an acrylic polymer containing an unsaturated group was used. In such a case, at least one of wear resistance, hardness and toughness was not sufficient.

Claims (7)

For a total of 100 parts by weight of the polyfunctional (meth) acrylate monomer and / or polyfunctional acrylate oligomer,
10 to 60 parts by weight of an acrylic polymer having no unsaturated group, having a hydrophilic functional group and having a weight average molecular weight of 5,000 to 200,000 in solid content A resin composition.   The resin composition according to claim 1, wherein the polyfunctional (meth) acrylate monomer and / or polyfunctional acrylate oligomer has three or more (meth) acryloyl groups.   The resin composition according to claim 1, further comprising a perfluoropolyether acrylate compound.   The resin composition according to claim 3, wherein the contact angle of the cured coating film with water is 90 degrees or more and the contact angle with oleic acid is 50 degrees or more.   Furthermore, a photoinitiator is contained, The resin composition in any one of Claims 1-4 characterized by the above-mentioned.   A molded product, wherein the resin composition according to any one of claims 1 to 5 is applied to a substrate.   The molded article according to claim 6, wherein a base material of the molded article is plastic.