JP5285355B2 - Resin composition and molded product - Google Patents

Description

  The present invention relates to an active energy ray-curable resin composition and a molded product.

  In recent years, active energy ray-curable coatings have been used in mobile phones, home appliances, optical films, and the like in place of conventional thermosetting coatings. 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 hardness and scratch resistance.

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. So, in addition to polyfunctional (meth) acrylates, high molecular weight urethane acrylate oligomers have been added to provide flexibility, which solves the problem of cracking easily. However, the crosslink density is reduced and wear resistance and hardness are reduced. There was a problem that would decrease. Patent Document 1 discloses an active energy ray-curable resin composition excellent in elongation and flexibility of a cured film. Although it is excellent in elongation and flexibility, the abrasion resistance and hardness are not sufficient. Therefore, an active energy ray-curable hard coat resin composition having toughness that is difficult to break, high wear resistance, and high hardness has been desired.
JP 2008-127475 A

The invention of claim 1 is a reaction of a polyfunctional acrylate monomer having a hydroxyl group with a polyvalent isocyanate monomer or a polyvalent organic polyisocyanate with respect to 100 parts by weight of the polyfunctional (meth) acrylate monomer and / or polyfunctional acrylate oligomer , Next, it is a resin composition characterized in that 20 to 80 parts by weight of a urethane acrylate oligomer having a weight average molecular weight of 30,000 to 300,000 is obtained by reacting a polyhydric alcohol .

  The invention of claim 2 is a resin composition wherein the polyfunctional (meth) acrylate monomer and / or polyfunctional acrylate oligomer has three or more (meth) acryloyl groups.

  The invention of claim 3 is an active energy ray-curable hard coat resin composition further comprising a photopolymerization initiator.

  A fourth aspect of the present invention is a molded article in which the resin composition is applied.

  The invention according to claim 5 is the molded article according to claim 7, characterized in that the base material of the molded article is plastic.

  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. 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, and electronic dictionaries.

Hereinafter, the present invention will be described in detail. The urethane acrylate oligomer used in the present invention can be synthesized by reacting a polyhydric alcohol, a polyvalent isocyanate monomer or polyvalent organic polyisocyanate, and a polyfunctional acrylate monomer having a hydroxyl group in the absence of a solvent or in an organic solvent. Examples of the polyhydric alcohol include acrylic polyols, polyester polyols, polycarbonate polyols, ethylene glycol, and propylene glycol. Polyhydric tolylene diisocyanate as isocyanate monomer, diphenylmethane diisocyanate, xylylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and the like, polyhydric organic polyisocyanate adduct type synthesized from isocyanate monomer, isocyanurate type, buret type Polyisocyanate etc. are mentioned. Examples of the polyfunctional acrylate monomer having a hydroxyl group include isocyanuric acid ethylene oxide-modified diacrylate, pentaerythritol triacrylate, and dipentaerythritol pentaacrylate.

  Since the urethane acrylate oligomer is synthesized using a polyfunctional acrylate monomer, the number of cross-linking points is increased, the cross-linking density is increased, and the coating film has high wear resistance and high hardness. In particular, when dipentaerythritol pentaacrylate having 5 acryloyl groups is used, the above effect becomes more remarkable. Further, when the weight molecular weight of the urethane acrylate oligomer is 30,000 to 300,000, it becomes a coating film having high wear resistance, hardness and toughness that is difficult to break at a higher level.

  In addition to the urethane acrylate oligomer as a curing component, the resin composition of the present invention is a polyfunctional (meth) acrylate monomer (hereinafter referred to as (meth) acrylic acid, (meth) acrylate, acrylic acid and / or methacrylic acid, Acrylate and / or methacrylate) and / or polyfunctional acrylate oligomers. The polyfunctional (meth) acrylate monomer can be used alone, or two or more polyfunctional (meth) acrylate monomers or resins having an unsaturated group with a low functional group number can be used in combination.

  Since the resin composition of the present invention achieves high wear resistance, hardness, and toughness at a high level, various molded products, especially digital devices such as mobile phones, digital cameras, and portable players, televisions, and washing machines. It can be applied to home appliances such as refrigerators, and all products such as automobile exterior paint and interior parts.

  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 Triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol pentaacrylate, propionic acid modified dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, caprolactone modified dipentaerythritol hexaacrylate, etc. The higher the surface hardness, the better. You may use these individually or in mixture of 2 or more types. 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 Examples include methacrylate, 1,10-decanediol dimethacrylate, glycerin dimethacrylate, dimethylol-tricyclodecane dimethacrylate, trimethylolpropane trimethacrylate, and ethoxylated trimethylolpropane trimethacrylate. These may be used alone or in combination of two or more. May be used.

  Examples of polyfunctional acrylate oligomers include urethane acrylate oligomers, epoxy acrylate oligomers, polyester acrylate oligomers, and acrylic acrylate oligomers, and these may be used alone or in admixture of two or more.

  It is preferable to blend 20-80 parts by weight of the urethane acrylate oligomer with respect to 100 parts by weight of the polyfunctional (meth) acrylate monomer and / or the polyfunctional acrylate oligomer. If it is less than 20 parts by weight, the wear resistance and hardness are further improved, but the toughness tends to be lowered, which is unsuitable for applications where toughness is important. If it exceeds 80 parts by weight, the toughness is further improved, but the wear resistance and hardness tend to decrease, making it unsuitable for applications where wear resistance and hardness are important.

  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.

Since the resin composition of the present invention has an unsaturated group, it can be cured in the presence of a suitable polymerization initiator. When using a photopolymerization initiator,
Since it can be cured in a short time by irradiating active energy rays such as ultraviolet rays, productivity can be improved and energy saving can be achieved.

  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 (manufactured by Ciba Specialty Chemicals); Lucirin LR8728 (manufactured by BASF); Darocur 1116, 1173 (manufactured by Merck); UCB) and the like.

  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, sufficient hardness is not generated, and when it exceeds 40 μm, cracks are generated, which is not preferable.

  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 sterilizers, bactericides, preservatives, plasticizers, flow regulators, antistatic agents, thickeners, pH adjusters, surfactants, leveling regulators, antifoaming agents, color pigments, rust preventive pigment You may add compounding materials, such as. Moreover, you may add antioxidant and a ultraviolet absorber for the purpose of a weather resistance improvement.

  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.

  100 parts by weight of dipentaerythritol pentaacrylate (trade name SR399, solid content 100%, manufactured by Sartomer, USA) and 114 parts by weight of isocyanate monomer (trade name Coronate HX, solid content 100%, manufactured by Nippon Polyurethane Industry Co., Ltd.) in MEK solvent (solid content) 30%) The mixture was stirred and reacted at 30 ° C. for 30 minutes, and the reaction was terminated when the peak of the isocyanate group became two-thirds by infrared absorption analysis. After adding 12 parts by weight of ethylene glycol to the acrylic modified isocyanate thus prepared, stirring and reacting at 10 ° C. for 30 minutes, stirring and reacting at 60 ° C. for 30 minutes, 2-hydroxyethyl acrylate (Kyoeisha Chemical Co., Ltd.) (Product name: Light Ester HOA, solid content: 100%) 0.4 parts by weight were added to stop the reaction, and urethane acrylate 1 having a weight average molecular weight of 50,000 was obtained. 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.

  Dipentaerythritol hexaacrylate (made by Shin-Nakamura Chemical Co., Ltd., trade name: A-DPH, solid content: 100%) 100 parts by weight of urethane acrylate 1, 30 parts by weight, 50 parts by weight, 80 parts by weight (solid content ratio) Then, 5 parts by weight of Irgacure 184 (manufactured by Ciba Specialty Chemical Co., Ltd.) as an initiator is added to 100 parts by weight of each resin solid content, and ethyl acetate is added as a solvent so that the solid content is 30%. The active energy ray-curable hard coat resin compositions of Examples 1 to 3 were obtained.

  100 parts by weight of dipentaerythritol pentaacrylate (trade name SR399, solid content 100%, manufactured by Sartomer, USA) and 114 parts by weight of isocyanate monomer (trade name Coronate HX, solid content 100%, manufactured by Nippon Polyurethane Industry Co., Ltd.) in MEK solvent (solid content) 30%) The mixture was stirred and reacted at 30 ° C. for 30 minutes, and the reaction was terminated when the peak of the isocyanate group became two-thirds by infrared absorption analysis. After adding 12 parts by weight of ethylene glycol to the acrylic-modified isocyanate thus prepared, stirring and reacting at 10 ° C. for 30 minutes, stirring and reacting at 60 ° C. for 2 hours, 2-hydroxyethyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.) The reaction was stopped by adding 0.2 parts by weight of a trade name Light Ester HOA (solid content 100%) to obtain urethane acrylate 2 having a weight average molecular weight of 100,000.

  30 parts by weight, 50 parts by weight and 80 parts by weight (solid content ratio) of the urethane acrylate 2 with respect to 100 parts by weight of dipentaerythritol hexaacrylate (trade name A-DPH manufactured by Shin-Nakamura Chemical Co., Ltd. 100%) By adding 5 parts by weight of Irgacure 184 (manufactured by Ciba Specialty Chemical Co., Ltd.) as an initiator to 100 parts by weight of each of the above resin solids, and adding ethyl acetate as a solvent so that the solids content is 30% The active energy ray-curable hard coat resin compositions of Examples 4 to 6 were obtained.

  100 parts by weight of dipentaerythritol pentaacrylate (trade name SR399, solid content 100%, manufactured by Sartomer, USA) and 114 parts by weight of isocyanate monomer (trade name Coronate HX, solid content 100%, manufactured by Nippon Polyurethane Industry Co., Ltd.) in MEK solvent (solid content) 30%) The mixture was stirred and reacted at 30 ° C. for 30 minutes, and the reaction was terminated when the peak of the isocyanate group became two-thirds by infrared absorption analysis. After adding 12 parts by weight of ethylene glycol to the acrylic modified isocyanate thus prepared, stirring and reacting at 10 ° C. for 30 minutes, stirring and reacting at 60 ° C. for 5 hours, 2-hydroxyethyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.) The reaction was stopped by adding 0.1 part by weight of a trade name Light Ester HOA (solid content 100%) to obtain urethane acrylate 3 having a weight average molecular weight of 250,000.

  30 parts by weight, 50 parts by weight, and 80 parts by weight (solid content ratio) of urethane acrylate 3 with respect to 100 parts by weight of dipentaerythritol hexaacrylate (trade name A-DPH manufactured by Shin-Nakamura Chemical Co., Ltd. 100%) By adding 5 parts by weight of Irgacure 184 (manufactured by Ciba Specialty Chemical Co., Ltd.) as an initiator to 100 parts by weight of each of the above resin solids, and adding ethyl acetate as a solvent so that the solids content is 30% The active energy ray-curable hard coat resin compositions of Examples 7 to 9 were obtained.

Comparative example

  Active energy ray curing of Comparative Examples 1 and 2 was carried out in the same manner as in Example 1 except that 10 parts by weight and 100 parts by weight (solid content ratio) of urethane acrylate 1 were blended with 100 parts by weight of dipentaerythritol hexaacrylate. A mold hard coat resin composition was obtained.

  Active energy ray curing of Comparative Examples 3 and 4 was carried out in the same manner as in Example 4 except that 10 parts by weight and 100 parts by weight (solid content ratio) of urethane acrylate 2 was blended with 100 parts by weight of dipentaerythritol hexaacrylate. A mold hard coat resin composition was obtained.

  Active energy ray curing of Comparative Examples 5 and 6 was carried out in the same manner as in Example 7, except that 10 parts by weight and 100 parts by weight (solid content ratio) of the urethane acrylate 3 was mixed with 100 parts by weight of dipentaerythritol hexaacrylate. A mold hard coat resin composition was obtained.

  100 parts by weight of dipentaerythritol pentaacrylate (trade name SR399, solid content 100%, manufactured by Sartomer, USA) and 114 parts by weight of isocyanate monomer (trade name Coronate HX, solid content 100%, manufactured by Nippon Polyurethane Industry Co., Ltd.) in MEK solvent (solid content) 30%) The mixture was stirred and reacted at 30 ° C. for 30 minutes, and the reaction was terminated when the peak of the isocyanate group became two-thirds by infrared absorption analysis. 12 parts by weight of ethylene glycol was added to the acrylic-modified isocyanate thus prepared, and the mixture was stirred and reacted at 10 ° C. for 60 minutes to give 2-hydroxyethyl acrylate (trade name Light Ester HOA solid content 100%, manufactured by Kyoeisha Chemical Co., Ltd.) 2 The reaction was stopped by adding .2 parts by weight to obtain urethane acrylate 4 having a weight average molecular weight of 20,000.

  Dipentaerythritol hexaacrylate (trade name: A-DPH manufactured by Shin-Nakamura Chemical Co., Ltd., 100% solid content) is mixed with 30 parts by weight and 80 parts by weight (solid content ratio) of urethane acrylate 4 to 100 parts by weight. Comparative Example 7 was obtained by adding 5 parts by weight of Irgacure 184 (manufactured by Ciba Specialty Chemical Co., Ltd.) as an agent to 100 parts by weight of each resin solid content and adding ethyl acetate as a solvent so that the solid content was 30%. And 8 active energy ray-curable hard coat resin compositions.

  100 parts by weight of dipentaerythritol pentaacrylate (trade name SR399, solid content 100%, manufactured by Sartomer, USA) and 114 parts by weight of isocyanate monomer (trade name Coronate HX, solid content 100%, manufactured by Nippon Polyurethane Industry Co., Ltd.) in MEK solvent (solid content) 30%) The mixture was stirred and reacted at 30 ° C. for 30 minutes, and the reaction was terminated when the peak of the isocyanate group became two-thirds by infrared absorption analysis. After adding 12 parts by weight of ethylene glycol to the acrylic modified isocyanate thus prepared, stirring and reacting at 10 ° C. for 30 minutes, stirring and reacting at 80 ° C. for 5 hours, 2-hydroxyethyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.) The reaction was stopped by adding 0.04 parts by weight of a trade name Light Ester HOA (solid content: 100%) to obtain urethane acrylate 5 having a weight average molecular weight of 400,000.

  Dipentaerythritol hexaacrylate (trade name A-DPH manufactured by Shin-Nakamura Chemical Co., Ltd., 100% solid content) is blended with 30 parts by weight and 80 parts by weight (solid content ratio) of the urethane acrylate with respect to 100 parts by weight. By adding 5 parts by weight of Irgacure 184 (manufactured by Ciba Specialty Chemical Co., Ltd.) to 100 parts by weight of each of the above resin solids, and adding ethyl acetate as a solvent so that the solids content is 30%, Comparative Example 9 and Ten active energy ray-curable hard coat resin compositions were obtained.

  12 functional urethane acrylate (trade name Art Resin UN-5500, solid content 50%, weight average molecular weight 50,000, manufactured by Negami Kogyo Co., Ltd.), 30 parts by weight and 80 parts by weight (solid content ratio), with 100 parts by weight of dipentaerythritol hexaacrylate ) Part, and 5 parts by weight of Irgacure 184 (manufactured by Ciba Specialty Chemical Co., Ltd.) as an initiator is added to 100 parts by weight of each resin solid content, and ethyl acetate is added as a solvent so that the solid content is 30%. Thus, active energy ray-curable hard coat resin compositions of Comparative Examples 11 and 12 were obtained.

The active energy ray-curable hard coat resin composition prepared in Examples and Comparative Examples was formed on an ABS plate (2 mm thickness) and a PET film (100 μm thickness) with a bar coater # 10 and dried at 80 ° C. for 1 minute. UV curing was performed at 300 mJ / cm ² to form a hard coat layer having a thickness of 5 μm.

Test / Evaluation Method Adhesiveness On each substrate, based on a cross-cut test based on JIS K 5600-5-6 (1999 edition), 10 × 10 squares were created on the coating surface, and cellophane tape (Nichiban) Paste CT-24), and pull upward to check the peeling condition. The number of squares that did not peel off was recorded.
Example 100/100 ... No peeling

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 Using steel wool (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 ... ◎, 5 or less scratches ... ○
5 to 10 scratches △, 10 or more scratches ×

Measurement of crack resistance A heat cycle test was performed on a test piece coated on ABS. 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 ... ×

  As shown in Table 1, the specimens using the resin compositions of the examples were excellent in wear resistance and hardness, and no cracks were generated. On the other hand, as shown in Table 2, the test body using each resin composition of the comparative example in which the molecular weight and the blending ratio of the urethane acrylate oligomer are not suitable was inferior in wear resistance and hardness or crack resistance.

Claims (5)

A polyfunctional acrylate monomer having a hydroxyl group and a polyvalent isocyanate monomer or a polyvalent organic polyisocyanate are reacted with 100 parts by weight of a polyfunctional (meth) acrylate monomer and / or a polyfunctional acrylate oligomer , and then a polyhydric alcohol is reacted. 20 to 80 parts by weight of a urethane acrylate oligomer having a weight average molecular weight of 30,000 to 300,000 is obtained .   The resin composition according to claim 1, wherein the polyfunctional (meth) acrylate monomer and / or the polyfunctional acrylate oligomer has three or more (meth) acryloyl groups.   The active energy ray-curable hard coat resin composition according to claim 1, further comprising a photopolymerization initiator.   A molded product, wherein the resin composition according to claim 1 is applied.   5. The molded product according to claim 4, wherein a base material of the molded product is plastic.