JP2012087176A - Coating material composition for metal thin film, and molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating material composition for metal thin films from which a cured layer having excellent adhesiveness to metal and excellent moisture resistance and hardness can be obtained, and a molded product laminated with the cured layer.SOLUTION: The coating material composition for metal thin films comprises vinyl caprolactam (component A), urethane (meth)acrylate (component B) having ≥2 radically polymerizable unsaturated bonds in one molecule and a compound (component C) having ≥1 radically polymerizable unsaturated bond in a molecule and copolymerizable with the component A and the component B. The amounts of the components A, B and C in the coating material composition for metal thin films are 0.5-15 mass% component A, 10-30 mass% component B and 55-85 mass% component C based on the sum total amount of the components A, B and C. The molded product is produced by laminating the cured layer of the coating material composition for metal thin films on the surface of a metal thin film-laminated molded product laminated with a metal thin film on the surface of a resin molded product.

Description

  The present invention relates to a coating material composition for metal thin film and a molded article.

  UV curable resin compositions are widely used from the viewpoint of productivity and energy saving, and especially undercoat materials and topcoats used for metallization processes such as hard coat processing, vacuum deposition, and sputtering on plastic molded products. It is used for materials.

  Examples of applications in which the ultraviolet curable resin composition is used include reflector parts such as lighting and lights, home appliances such as a mobile phone, and decoration applications for cosmetic containers.

  In these decorative applications, for example, a reflector formed with a metal vapor deposition layer such as aluminum on the surface of the reflector part is used. In order to protect the metal vapor deposition layer, an ultraviolet curable resin composition is formed on the surface of the metal vapor deposition layer. The cured coating film is laminated.

  As an ultraviolet curable resin composition for protecting a metal vapor-deposited layer, for example, in Patent Document 1, a metal vapor-deposited topcoat containing a specific polymer (P), a radical polymerizable compound (M) and a photoinitiator (C) is used. A photocurable coating composition for use has been proposed.

  In order to give good adhesion to metal, for example, Patent Document 2 contains at least one monomer selected from N-acryloylmorpholine, N-vinylformamide, and N-vinylcaprolactam in the paint. It has been proposed to let

JP 2006-169,308 A JP-A-10-183,014

  In such a situation, the case of the cellular phone or the like needs to be electrically non-conductive in order to allow radio waves to pass therethrough, and vapor deposition technology using tin as a metal to be vapor deposited is used.

  When the resin composition of Patent Document 1 is used as a coating composition for coating the surface of such tin metal, there is a problem that adhesion to tin metal is low.

  Moreover, when the composition of patent document 2 is coat | covered on the metal surface, although it is excellent in the adhesiveness to a metal, there exists a problem that the hardness of a hardened layer is not enough.

  INDUSTRIAL APPLICABILITY The present invention provides a metal thin film coating material composition capable of obtaining a cured layer having excellent adhesion to a tin metal surface and having excellent moisture resistance and hardness, and metal on the surface of a resin molded product. It is an object of the present invention to provide a molded product in which a cured layer of a coating composition for a metal thin film is laminated on the surface of the metal thin film of the metal thin film laminate molded product in which the thin film is laminated.

  The gist of the present invention is that vinyl caprolactam (component A), urethane (meth) acrylate (component B) having two or more radical polymerizable unsaturated bonds in one molecule, and copolymerization with components A and B A coating material composition for a metal thin film containing a compound (C component) having at least one radical polymerizable unsaturated bond in a possible molecule, wherein the blending amount of A component, B component and C component is A A coating composition for a metal thin film in which the A component is 0.5 to 15% by mass, the B component is 10 to 30% by mass, and the C component is 55 to 85% by mass based on the total amount of the component, the B component, and the C component. The product (hereinafter referred to as “the present coating material composition”) is the first invention.

  Further, the gist of the present invention is that a molded product in which a cured layer of the present coating material composition is laminated on the surface of a metal thin film of a metal thin film laminated molded product in which a metal thin film is laminated on the surface of a resin molded product (hereinafter referred to as a molded product) , Referred to as “the present molded product”).

  Since the cured layer of the present coating material composition has excellent adhesion to the tin metal surface and has excellent moisture resistance and hardness, the molded product is a reflector for lighting, light, etc. It is suitable for various applications such as reflector parts, household electric appliances such as mobile phones, and cosmetic containers.

A component A component (vinyl caprolactam) used for this invention is one of the structural components of this coating | covering material composition.

B component B component used for this invention is one of the structural components of this coating | covering material composition, and is urethane poly (meth) acrylate which has a 2 or more radically polymerizable unsaturated bond in 1 molecule.

  As B component, the urethane di (meth) acrylate obtained by reaction of a polyhydric alcohol (b-1), diisocyanate (b-2), and a hydroxyalkyl (meth) acrylate (b-3) is mentioned, for example.

  In the present invention, “(meth) acrylate” represents at least one selected from “acrylate” and “methacrylate”.

  Examples of the polyhydric alcohol (b-1) include polyether polyols such as polyethylene glycol and polypropylene glycol; ethylene glycol, diethylene glycol, propylene glycol, 1,6-hexanediol, 1,4-butanediol, and tricyclodecanedi. Polyhydric alcohols such as methanol, hydrogenated bisphenol A, bisphenol A, trimethylolpropane and pentaerythritol; polyether-modified polyols obtained by adding alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide to the polyhydric alcohols; Polylactone polyols obtained by reaction of alcohols with lactones such as ε-caprolactone; polycarbonate diols; and polybutadiene glycols. It is. These can be used alone or in combination of two or more.

  Examples of the diisocyanate (b-2) include tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, and methylcyclohexane diisocyanate. These can be used alone or in combination of two or more.

  Among these, isophorone diisocyanate is preferable in that the viscosity of the component B is low and the workability during coating of the present coating material composition is good.

  Examples of the hydroxyalkyl (meth) acrylate (b-3) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth). Examples include hydroxyl group-containing (meth) acrylates such as acrylate and pentaerythritol tri (meth) acrylate, and caprolactone-modified products and alkyl oxide-modified products thereof. These can be used alone or in combination of two or more.

  Among these, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 4-hydroxy are low in that the viscosity of the component B is low and the workability during coating of the present coating material composition is improved. Butyl (meth) acrylate is preferred.

  As a manufacturing method of urethane di (meth) acrylate obtained by reaction of diol (b-1), diisocyanate (b-2), and hydroxyalkyl (meth) acrylate (b-3), the following method is mentioned, for example.

  First, diisocyanate (b-2) is dropped into a mixture of diol (b-1) heated to 30 to 90 ° C. and a catalyst such as dibutyltin dilaurate over 2 to 6 hours, and further reacted for 1 to 3 hours. Let

  Next, hydroxyalkyl (meth) acrylate (b-3) is dropped into the obtained reaction solution over 1 to 3 hours, and further reacted for 1 to 3 hours to obtain urethane di (meth) acrylate.

C component The B component used in the present invention is one of the components of the present coating composition, and at least one or more in one molecule other than the A component and the B component copolymerizable with the A component and the B component. It is a compound having a radically polymerizable unsaturated bond.

  Examples of the component C used in the present invention include dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, caprolactone-modified dipentaerythritol hydroxypenta ( (Meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate , Tricyclodecane dimethanol di (meth) acrylate, di (meth) acrylate of caprolactone adduct (2-5 addition moles) of bisphenol A, 2-ethylhexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, Examples include dicyclopentenyl (meth) acrylate, 2-dicyclopentenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, and tetrahydrofurfuryl (meth) acrylate. These can be used alone or in combination of two or more.

  Among these, (meth) acrylates having 2 or more functional groups are preferable in terms of the balance between the heat resistance of the cured layer of the present coating material composition and the smoothness of the coating film surface of the present coating material composition. (Meth) acrylate is more preferred.

The present covering material composition The present covering material composition contains an A component, a B component and a C component.

  The blending amount of the A component is 0.5 to 15% by mass, preferably 1 to 5% by mass, based on the total amount of the A, B and C components in the present coating material composition. When the blending amount of component A is 15% by mass or less, the hardness of the cured layer of the present coating material composition is good, and when it is 0.5% by mass or more, the adhesion between the cured layer of the present coating material composition and the metal is good. is there.

  The compounding quantity of B component is 10-30 mass% on the basis of the total amount of A component, B component, and C component in this coating | covering material composition, Preferably it is 15-25 mass%. The hardness of the cured layer of the present coating material composition is good when the blending amount of the component B is 30% by mass or less, and the adhesion between the cured layer of the present coating material composition and the metal is good at 10% by mass or more.

  The amount of component C is 55 to 85% by mass, preferably 70 to 80% by mass, based on the total amount of component A, component B and component C in the present coating composition. When the amount of component C is 85% by mass or less, the adhesion between the cured layer of the present coating material composition and the metal is good, and when it is 55% by mass or more, the hardness of the cured layer of the present coating material composition is good.

  In this invention, when hardening this coating | covering material composition with an active energy ray, a photoinitiator can be mix | blended with this coating | covering material composition.

  Examples of the photopolymerization initiator include benzoin, benzoin monomethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, acetoin, benzyl, benzophenone, p-methoxybenzophenone, diethoxyacetophenone, benzyldimethyl ketal, 2,2-diethoxyacetophenone, Carbonyl compounds such as 1-hydroxycyclohexyl phenyl ketone, methylphenylglyoxylate, ethylphenylglyoxylate, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-ethylanthraquinone; tetramethylthiuram monosulfide Sulfur compounds such as tetramethylthiuram disulfide; and acyl phosphines such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide. Fins oxide. These can be used alone or in combination of two or more. Among these, benzophenone and methylphenylglyoxylate are preferable from the viewpoint of curability of the present coating material composition.

  As for the compounding quantity of a photoinitiator, 0.1-15 mass parts is preferable with respect to 100 mass parts of this coating | covering material composition.

  In the present invention, a known light such as methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, amyl 4-dimethylaminobenzoate, 4-dimethylaminoacetophenone or the like is optionally contained in the coating composition. A sensitizer can be blended.

  Further, if necessary, an organic solvent can be added to adjust the present coating material composition to a desired viscosity.

  Examples of the organic solvent include ketone compounds such as acetone, methyl ethyl ketone, and cyclohexanone; ester compounds such as methyl acetate, ethyl acetate, butyl acetate, ethyl lactate, and methoxyethyl acetate; alcohol compounds such as ethanol, isopropyl alcohol, and butanol, diethyl ether And ether compounds such as ethylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether and dioxane; aromatic compounds such as toluene and xylene; and aliphatic compounds such as pentane, hexane and petroleum naphtha.

  The blending amount of the organic solvent is preferably 100 to 500 parts by mass with respect to 100 parts by mass of the present coating material composition.

  In this coating material composition, a leveling agent, an antifoaming agent, an anti-settling agent, a lubricant, an abrasive, an antirust agent, an antistatic agent, a light stabilizer, an ultraviolet absorber, a polymerization inhibitor, etc. Additives can be blended.

Metal thin film In the present invention, the metal thin film is laminated on the surface of a resin molded product.

  Examples of the metal forming the metal thin film include aluminum and tin.

  In the present invention, the thickness of the metal thin film is about 10 to 100 nm.

Resin Molded Product Examples of the resin molded product used in the present invention include a molded product obtained from at least one resin selected from ABS resin, PC resin, AS resin, and PP resin.

Metal thin film laminate molded product In the present invention, a metal thin film laminate molded product is a product in which a metal thin film is laminated on the surface of a resin molded product.

  In addition, in this invention, what has an undercoat layer as needed between a resin molded product and a metal thin film can be used as a metal thin film lamination molded product.

  Examples of the undercoat material for forming the undercoat layer include known thermosetting compositions and active energy ray curable compositions.

  Examples of a method for obtaining a metal thin film laminate molded product include the following methods.

  First, an undercoat material is applied to the surface of the resin molded product and then cured to form an undercoat layer on the surface of the resin molded product. Thereafter, a metal thin film is formed on the surface of the formed undercoat layer by a vacuum deposition method, an ion plating method, a sputtering method, or the like to obtain a metal thin film laminated resin molded product.

Main molded product The main molded product is obtained by laminating a cured layer of the present coating material composition on the surface of a metal thin film of a metal thin film laminated molded product.

  The thickness of the cured layer of the present coating material composition is about 3 to 40 μm in terms of maintaining the hardness of the cured layer of the present coating material composition and maintaining good adhesion between the cured layer of the present coating material composition and the metal. Is preferred.

  Examples of the method for applying the present coating material composition to the surface of the metal thin film of the metal thin film laminate molding include a brush coating method, a spray coating method, a dip coating method, a spin coating method, and a flow coating method.

  Among these, the spray coating method and the flow coating method are preferable in terms of the coating workability of the present coating material composition and the smoothness and uniformity of the coating film of the present coating material composition.

  In the case of using an organic solvent blended as the coating material composition, the solvent in the coating film of the coating material composition obtained by applying the coating material composition is volatilized, and then the coating material is coated. The material composition is cured.

  Examples of the method for volatilizing the solvent include a method of heating at 40 to 130 ° C. for 1 to 20 minutes with an infrared heater or warm air.

  Examples of the method of curing the coating film of the present coating material composition include a method of curing by irradiation with active energy rays.

  Examples of the active energy rays include ultraviolet rays and electron beams.

As an irradiation condition of the active energy ray, for example, when a high-pressure mercury lamp is used, the amount of irradiated ultraviolet energy is about 500 to 4,000 mJ / cm ² .

  This molded product can be used for various applications such as lighting, reflectors such as lights, reflector parts, home appliances such as mobile phones, and cosmetic containers.

  Hereinafter, the present invention will be described with reference to examples. In the following, “part” means “part by mass”. Moreover, various evaluations of the cured layer of the coating material composition were performed by the following methods.

(1) Adhesiveness Adhesiveness between the cured layer of the coating composition and the metal was evaluated by a cross-cut peel test.
The hardened layer surface of the laminated moldings in the coating composition to the surface of the metal thin film of the metal thin film lamination molding, crosscut reaching at 1mm intervals until the resin molding with a cutter knife, a crosscut of 1mm ² 100 were created. Cellophane tape was affixed on the created grids, and after peeling off rapidly, the peeled grids were counted. Adhesion was determined according to the following criteria.
“◯”: No peeling.
“Δ”: Number of peels 1 to 50.
"X": The number of peeling is 51 to 100.

(2) Moisture resistance A molded product obtained by laminating a cured layer of a coating material composition on the surface of a metal thin film of a metal thin film laminate molded product was placed in a constant temperature and humidity chamber at 80 ° C. and a relative humidity of 85% for 24 hours. Next, the molded product was taken out from the thermo-hygrostat, and a cross cut reaching the resin molded product was put on the surface of the cured layer of the coating material composition with a cutter knife to create 100 1 mm ² grids. Cellophane tape was affixed on the created grids, and after peeling off rapidly, the peeled grids were counted. The determination of moisture resistance was performed according to the following criteria.
“◎”: No peeling.
“◯”: Number of peels 1 to 10.
“Δ”: 11 to 50 peels.
"X": The number of peeling is 51 to 100.

(3) Hardness The surface of the molded product obtained by laminating the hardened layer of the coating material composition on the surface of the metal thin film of the metal thin film molded product is rubbed twice with steel wool (# 0000, manufactured by Bonstar Co., Ltd.) The ease of scratching the surface of the molded product was visually observed, and the hardness was evaluated according to the following criteria.
“◎”: There is no scar.
“◯”: There is a slight scar.
“△”: A scar remains clearly.
“×”: Many scars remain.

[Production Example 1] Production of urethane diacrylate (B-1) (1) In a 3 L four-necked flask, bisphenol A propylene oxide adduct (trade name: Adeka Polyether BPX-11, manufactured by ADEKA) 285 g Then, 21 g of neopentyl glycol and 0.2 g of dibutyltin dilaurate were charged, and heated with a water bath so that the internal temperature became 60 ° C.
(2) Next, 436 g of isophorone diisocyanate was charged into a dropping funnel with a side tube, and the temperature in the flask was adjusted to 60 ° C. while stirring the contents in the flask prepared in (1) above. While keeping it in the flask by dropping at a constant rate for 2 hours, isophorone diisocyanate was reacted by stirring the contents at the same temperature for 1 hour.
(3) Thereafter, the temperature of the flask contents obtained in (2) was raised to 70 ° C., and 232 g of 2-hydroxyethyl acrylate charged in another dropping funnel and 2,6-di-tert-butyl-4- A uniform mixed solution of 1.5 g of methylphenol was dropped into the flask by constant rate dropping for 1 hour while keeping the temperature inside the flask at 70 ° C. Then, the temperature of the flask contents was kept at 70 ° C. and stirred for 6 hours to produce urethane diacrylate (B-1) having a polystyrene-reduced weight average molecular weight of 6,800 by GPC measurement.

[Production Example 2] Production of polymer (D) 500 g of toluene was charged into a 2 L four-necked flask and heated so that the internal temperature became 80 ° C. Next, 250 g (50% by mass) of methyl methacrylate, 175 g (35% by mass) of styrene, and 75 g (15% by mass) of hydroxyethyl methacrylate and 1 g of azobisisobutylnitrile as a polymerization catalyst were mixed, and the inside of the flask was stirred. While maintaining the internal temperature at 80 ° C., the solution was added dropwise at a constant rate for 2 hours. Thereafter, 0.2 g of azobisisobutylnitrile is added 4 times in total every hour, and the mixture is stirred for 6 hours to give a copolymer having a weight average molecular weight of 3.2 × 10 ^{4 in} terms of polystyrene by GPC measurement (Polymer D). Got.

[Example 1]
The raw material of the coating material composition having the composition shown in Table 1 (the numerical value is parts by mass) was put into a stainless steel container and stirred for about 30 minutes until the whole became uniform to prepare the coating material composition (1).

  An undercoat material (trade name: Diabeam UM-479U, manufactured by Mitsubishi Rayon Co., Ltd.) is applied to a test piece of an ABS resin molded product having a width of 5 cm, a length of 9 cm, and a thickness of 3 mm. It was spray painted so that

The test piece coated with the undercoat material was kept in a hot air dryer at 60 ° C. for 5 minutes to volatilize the organic solvent. Next, the undercoat material coated surface of the obtained test piece was irradiated with an active energy ray under the conditions of a wavelength of 340 to 380 nm and an integrated light quantity of 1,000 mJ / cm ² using a high-pressure mercury lamp. A formed test piece was obtained.

  Next, using a vacuum deposition apparatus (trade name: EBX-6D) manufactured by Nippon Vacuum Technology Co., Ltd., tin was vacuum deposited on the surface of the undercoat layer of the test piece so that the tin film thickness was about 100 nm. A test piece on which a tin thin film was laminated was obtained.

  Then, the above-mentioned coating material composition (1) was spray-coated on the surface of the tin thin film of the test piece so that the film thickness after hardening might be 5-10 micrometers.

Furthermore, the test piece on which the coating material composition (1) was spray-coated was kept in a 60 ° C. hot air dryer for 5 minutes to volatilize the organic solvent, and then the test piece coating material composition ( The coating film of 1) was irradiated with active energy rays under the conditions of a wavelength of 340 to 380 nm and an integrated light quantity of 1,000 mJ / cm ² using a high-pressure mercury lamp to obtain a molded product. Table 1 shows the evaluation results of the obtained molded product.

The abbreviations in Table 1 represent the following compounds.
NVC: Vinyl caprolactam UA: Urethane diacrylate (B-1)
PETA: Pentaerythritol tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: NK ester A-TMMT)
DPHA: Dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name: KAYARAD DPHA)
IBXA: Isobornyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name: IBXA)
Ir184: 1-hydroxycyclohexyl phenyl ketone (Ciba Japan Co., Ltd., trade name: Irgacure 184)
MIBK: Methyl isobutyl ketone MEK: Methyl ethyl ketone

[Examples 2 to 4 and Comparative Examples 1 to 6]
A molded product was obtained in the same manner as in Example 1 except that the coating material composition having the composition shown in Table 1 was used. Table 1 shows the evaluation results of the obtained molded product.

  In Examples 1 to 4, it can be seen that the cured layer of the coating material composition on the surface of the molded article is excellent in adhesion to the metal thin film, moisture resistance and hardness.

  In contrast, in Comparative Example 1, since the component A was not blended in the coating material composition, the adhesion and moisture resistance of the cured layer of the coating material composition on the surface of the molded product to the metal thin film were poor. .

  In Comparative Example 2, the amount of component A and component B in the coating composition was too large, the moisture resistance of the cured layer of the coating composition on the surface of the molded product was insufficient, and the hardness was poor. It was.

  Furthermore, in Comparative Example 3, the amount of component B in the coating composition was too small, the adhesion of the cured layer of the coating composition on the surface of the molded product was insufficient, and the moisture resistance was poor.

  In Comparative Example 4, the amount of component A was too large, and the moisture resistance and hardness of the cured layer of the coating material composition on the surface of the molded product were insufficient.

  Further, in Comparative Example 5, the amount of component B was too large, and the hardness of the cured layer of the coating material composition on the surface of the molded product was insufficient.

  Further, in Comparative Example 6, since the A component and the B component were not blended, the adhesion and moisture resistance with the metal thin film of the cured layer of the coating material composition on the surface of the molded product were poor.

Claims (2)

  Vinyl caprolactam (component A), urethane (meth) acrylate having two or more radically polymerizable unsaturated bonds in one molecule (component B), and at least one in one molecule copolymerizable with components A and B A coating composition for a metal thin film containing a compound having a radical polymerizable unsaturated bond (C component), wherein the blending amounts of the A component, the B component and the C component are the sum of the A component, the B component and the C component. A coating material composition for a metal thin film in which the A component is 0.5 to 15% by mass, the B component is 10 to 30% by mass, and the C component is 55 to 85% by mass based on the amount.   The molded product in which the cured layer of the coating material composition for metal thin film according to claim 1 is laminated on the surface of the metal thin film of the metal thin film laminate molded product in which the metal thin film is laminated on the surface of the resin molded product.