JPS62783B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a synthetic material with excellent surface properties, namely abrasion resistance, scratch resistance, smoothness, and optical properties, as well as excellent flexibility, (hot) water resistance, and weather resistance. Related to resin laminate molded products. Today, synthetic resins are used in a wide range of fields as fibers, films, sheets, and other molded products, but they are also used in optical applications such as organic glasses, optical lenses, various display devices, decorative items, and various other products. When used in optical films, the lack of surface hardness is a fatal flaw. In other words, because the surface hardness is insufficient, the surface is easily scratched by contact with other objects, collisions, and attraction, resulting in loss of aesthetic appearance and deterioration of optical properties. In order to improve this drawback, conventional silicone hardened coatings, melamine resin hardened coatings,
Attempts have been made to form a cured film of a polyfunctional (meth)acryloyl group on the surface of a synthetic resin molded article. However, when using these methods to form a coating with high surface hardness on the surface of a synthetic resin molded product, increasing the hardness makes the coating brittle and prone to cracking, and the adhesion to the synthetic resin molded product is impaired. It is normal to be Therefore, the current situation is to improve flexibility and adhesiveness at the expense of surface hardness. In particular, it is possible to form a cured film that has excellent crack resistance, scratch resistance, abrasion resistance, adhesion, as well as water resistance, weather resistance, etc. on films and sheets that require flexibility. It had not been done. The present inventors conducted extensive research to solve the above problems, and were able to obtain a synthetic resin molded product with excellent scratch resistance, abrasion resistance, crack resistance, adhesion, water resistance, and weather resistance. . That is, the present invention provides: (1) An isocyanate group-containing compound is applied to the surface of a synthetic resin molded product at a solid content of 0.01 g/m 2 to ² g/m2.
Coated and laminated to a thickness of m ² , and on top of that,
A laminate molded product in which a compound containing three or more acryloyloxy groups or/and methacryloyloxy groups in the molecule is coated and cured so that the film thickness after curing is 1 μ to 20 μ. 98% by weight of the raw material forming a cured product of a compound containing 3 or more acryloyloxy groups and/or methacryloyloxy groups
The present invention relates to a laminate molded product which is a compound based on an unsaturated monomer containing three or more methacryloyloxy groups and/or acryloyloxy groups. The present invention involves coating and laminating an isocyanate group-containing compound on a synthetic resin molded article, and then forming a high hardness coating mainly composed of a cured coating of a compound containing three or more (meth)acryloyloxy groups. It is characterized by being forced. By coating and laminating this isocyanate group-containing compound thinner than a specific thickness, it is possible to improve adhesive properties (especially adhesive resistance (heat resistance)).
It is possible to form a high-hardness coating with extremely excellent crack resistance, etc., and the hardness of the high-hardness coating can be designed to be even harder than before. The present invention will be explained in more detail. In the present invention,
Synthetic resin molded products are fibers, films, sheets, lenses, pipes, bottles, containers, and other molded products molded from ordinary synthetic or semi-synthetic thermoplastic resins or thermosetting resins, and especially films, Film-like molded products such as sheets, lenses, pipes, and hollow containers are suitable. The thickness of these films is usually 3μ to 5μ
mm, preferably 4 μ to 1 mm. These molded products may be molded by conventional molding methods such as extrusion and injection. The surface of the obtained molded article may be subjected to pretreatments such as cleaning, etching, corona discharge, flame treatment, printing, etc. Examples of thermoplastic resins include polyolefins such as polyethylene and polypropylene, polysubstituted olefins such as polymethyl methacrylate, polyacrylonitrile, polystyrene, and polyvinyl chloride, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polycarbonate, poly-ε-caprolactam, and polyester. Examples include polyamides such as hexamethylene adipate and cellulose derivatives such as cellulose triacetate. These also include copolymers (including block and graft copolymers), blends (blends of rubber components, etc.), and polymer reactants (polyvinyl butyral, etc.). Examples of thermosetting resins include unsaturated polyester resins, phenolic resins, urea resins, melamine resins, and epoxy resins. Isocyanate-containing compounds include (1) compounds having two or more isocyanate groups in the molecule, or (2) compounds (low molecular weight or/and It mainly includes compositions containing (high molecular weight compounds). Compounds having two or more isocyanate groups include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and cyclohexane-bis-(methylene isocyanate).
or reaction products of these isocyanates and polyols (trimethylolpropane, pentaerythritol, etc.) in which the main free radicals are
Compounds having an NCO group, which are commercially available under trade names such as Desmodyur (L, R, type), Coronate (L, HL, R type), Millionate MR, Takenate, etc., can be used. A compound having an active hydrogen terminal that can react with an isocyanate group has a low molecular weight or/
and high molecular weight polyols, polyamines, etc. Polyester diols and polyether diols are mainly used. The isocyanate-containing compound is usually diluted with an organic solvent, applied on a synthetic resin molded article in a conventional manner, and heated to evaporate the organic solvent and at the same time react some or all of the isocyanate groups. , to form a thin, uniform and strong layer on the surface of a synthetic resin molded product. In this case, the organic solvents used include ester-based solvents such as ethyl acetate, ketone-based solvents such as methyl ethyl ketone, chlorine-based solvents such as methylene chloride, and hydrocarbon-based solvents such as toluene. Heating is usually 40℃~180℃, preferably 50℃~160℃
It is ℃. The thickness of the laminated layer has an important meaning in the present invention, and is usually 0.01 g/m ² to 2 as solid content.
g/m ² , preferably 0.1 to 0.5 g/m ² . 0.01
If it is thinner than 2g/ ^m2 , it is difficult to layer it uniformly, and if it is more than 2g/ ^m2 , even if a polyfunctional unsaturated monomer cured film is formed on it, it will not have good wear resistance or scratch resistance. It is difficult to obtain a laminate molded product with excellent properties and crack resistance, which is undesirable. By coating and laminating an isocyanate group-containing compound as an intermediate layer, the adhesiveness of the polyfunctional unsaturated monomer cured film can be improved.
Since the (boiling) water resistance and crack resistance are improved, it is possible to select a polyfunctional monomer composition that forms a highly hard film that was previously not applicable due to adhesion and crack resistance. It is. Compounds containing at least three or more acryloyloxy groups and/or methacryloyloxy groups in the molecule (hereinafter sometimes referred to as polyfunctional (meth)acryloyloxy group-containing compounds) are polyfunctional unsaturated monomers or/and A composition containing the initial radical reactant as a main component, in which a polyfunctional unsaturated monomer containing at least three or more (meth)acryloyloxy groups in the molecule is combined with a total unsaturated monomer. Refers to a composition comprising an unsaturated monomer mixture and/or its initial radical reactant, containing 50% by weight or more, preferably 70% by weight, particularly preferably 90% by weight or more. Examples of polyfunctional unsaturated monomers containing three or more (meth)acryloyloxy groups in the molecule include pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, and trimethylolpropane tri(meth)acrylate. , trimethylolethane tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like. Unsaturated monomers that can be used together with these include unsaturated monomers having two or one (meth)acryloyloxy group in the molecule and other vinyl monomers. The above bifunctional monomer is a hydrocarbon residue, a polyether residue, or a polyester residue in which the group bonding between each (meth)acryloyloxy group in one molecule contains 100 or less carbon atoms. Certain monomers are preferred. For example, ethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate , polyester diol di(meth)acrylate, etc. As the monofunctional monomer, 2-hydroxymethyl (meth)acrylate, glycidyl (meth)acrylate, (meth)acrylic acid, quaternary ammonium salts of (meth)acrylic esters, etc. can be used. These unsaturated monomers can be applied as they are, but they can also be used after being diluted with an organic solvent.
In addition, in order to improve the flatness of the cured coating film, a trace amount of photopolymerization initiator and/or radical initiator is added to the unsaturated monomer solution, and the solution is heated at room temperature to 100°C (preferably below 50°C). It is preferable to carry out the radical (polymerization) reaction at temperature (precure). This reaction is carried out under an inert gas atmosphere, and oxygen-containing gas is blown in to stop the reaction before gel is formed. Preferred organic solvents include ketone solvents such as methyl ethyl ketone and ether solvents such as methyl cellosolve. In order to efficiently cure the polyfunctional unsaturated monomer and/or its initial radical reactant used in the present invention after application, a photopolymerization initiator or/and radical initiator is usually used as a curing catalyst to fully unsaturated monomers and/or their initial radical reactants. 0.01 to 10% by weight, preferably 0.1 to 10% by weight, based on the monomer or/and its initial radical reactant
Add 5% by weight. Examples of photopolymerization initiators include benzoin (or its ethers) such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether, benzophenone,
Benzophenone series such as p-chlorobenzophenone and p-methoxybenzophenone, naphthoquinone series, anthraquinone series, 3,3',4,4'-benzophenone tetracarboxylic acid derivatives, and tetramethylthiuram disulfide. Examples include sulfur compounds such as hydride, tetramethylthiuram monosulfide, and the like. As a radical initiator, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, benzoyl peroxide, t-
Examples include peroxides such as butyl peroxybenzoate, methyl ethyl ketone peroxide, and di-t-butyl peroxide, and azo compounds such as azobisisobutyronitrile and azobis-2,4-dimethylvaleronitrile. Of course, it may be used in combination with amines and the like. The polyfunctional (meth)acryloyloxy-containing compound may further contain an ultraviolet absorber, a dye, a lubricant, and the like. The method for applying the compound containing the polyfunctional unsaturated monomer of the present invention or/and its initial radical reactant as a main component to a synthetic resin molded article is as follows:
Conventionally commonly used dip methods, spray methods, or roll coating methods such as gravure coating, reverse roll, and kiss roll methods can be arbitrarily applied. After coating the compound, heating and/or irradiation with actinic rays is used to cure the coating, with or without drying the solvent. Curing conditions by heating vary depending on the type and concentration of the radical initiator contained in the compound, but are usually 70°C to 200°C, preferably 80°C.
℃~180℃ for 10 seconds to 10 minutes, preferably 20 seconds~
It's 2 minutes. Curing by irradiation with actinic light is usually
Commonly used high-pressure mercury lamps, low-pressure mercury lamps,
This is carried out by irradiating light with a wavelength of 200 mμ to 800 mμ using a xenon lamp or the like. Irradiation conditions vary depending on the type and concentration of the photopolymerization initiator contained in the compound, the irradiation atmosphere, etc., but usually a high-pressure mercury lamp is used at an intensity of 50 W/m ² to 400 W/m ² for 1 irradiation.
It can be cured by irradiation for 1 second to 1 minute. The thickness of the cured film is usually 1 to 20 microns, preferably 3 to 6 microns. If it is less than 1μ, it is wear resistant.
Scratch resistance is poor, and if it exceeds 20μ, the cured film will have poor flexibility and cracks will easily occur, which is not preferable. The laminate molded product of the present invention has surface hardness, wear resistance,
It has excellent scratch resistance, and the hardened film formed on the surface has excellent flexibility and adhesion, so the film will not peel, craze, or crack even under harsh conditions, making it suitable for window glass and lenses. It is effectively used in applications such as watches, instrument covers, and mirrors. or,
One of the preferred embodiments of the laminate molded product of the present invention is a film-shaped molded product, which can be applied to window glass for purposes such as scatter prevention and sunlight control, and can be used as labels, stationery, daily necessities, toys, stamping foil, etc. For use as various photographic and video films, for decoration and displays by pasting on glass or metal plates,
Effectively used for various surface protection purposes. The contents of the present invention will be explained in more detail below with reference to Examples. In addition, various evaluations in the examples were performed by the following methods. (1) Abrasion resistance (a) Scratch test......on #0000 steel wool
A load of 100 g/cm ² was applied to the coating, and the coating was rubbed back and forth 10 times at a distance of 10 cm to see if it would cause scratches. (b) Sand drop method...80° on the coating surface tilted at 45°.
1000 g of mesh carborundum was dropped from a height of 635 mm, and the haze (%) of the scratches on the surface was measured using a haze meter (Toyo Seiki Haze Meter S-3). (2) Adhesion to the base material Cross-cut peel test......Create 100 squares with a side of 1 mm that reach the base material using a knife on the coating surface, and apply cellophane adhesive tape (Nichiban Co., Ltd., product name: Cellotape) on top of them. Evaluation was made based on the number of coatings remaining after application and rapid peeling. (3) Flexibility: A glass rod was wound around a glass rod with the cured coating surface facing outward, and the minimum diameter of the glass rod without causing cracks was measured. (4) Water resistance: After being immersed in water at 40℃ for 30 days,
It was investigated whether there was a decrease in abrasion resistance, adhesion to substrates, and flexibility. (5) Boiling water resistance: After being immersed in boiling water for 1 hour,
It was investigated whether there was a decrease in abrasion resistance, adhesion to substrates, and flexibility. In addition, pentaerythritol tetraacrylate in Examples and Comparative Examples is manufactured by Shin Nakamura Chemical Co., Ltd.
NK ester A-TMM-T was used. Reference example 1 40 parts of pentaerythritol tetraacrylate and 60 parts of methyl cellosolve in a flask equipped with a stirrer.
1 part, and 0.02 part of benzoin ethyl ether were added to make a homogeneous solution. The viscosity of this solution was 4CPS.
The system is placed in a nitrogen atmosphere and is stirred vigorously.
Ultraviolet rays were irradiated for 1 minute using a 400W high-pressure mercury lamp, and stirring was continued for 18 minutes, after which air was introduced to stop the reaction. The viscosity of the solution at this time was 10 CPS.
Next, 8% by weight of benzoyl peroxide based on pentaerythritol tetraacrylate was added to this solution to prepare a coating composition. Example 1 Takerakatsu A-371, manufactured by Takeda Pharmaceutical Co., Ltd.
15 parts of Takenate A-3 and 3.3 parts of Takenate A-3 were dissolved in 400 parts of methyl ethyl ketone and applied to a 50μ thick biaxially stretched polyethylene terephthalate film using a gravure coater and heated at 160°C for 1 minute to form a thin, uniform coating on the film surface. was formed. The coating amount was 0.2 g/m ² as solid content. Next, the coating composition prepared in Reference Example 1 was applied onto this coating using a gravure coater and heated at 160° C. for 1 minute to form a highly hard coating with a thickness of 3 μm. Comparative Example 1 The coating composition prepared in Reference Example 1 was applied to a polyethylene terephthalate biaxially stretched film with a thickness of 50 μm using a gravure coater and heated at 160° C. for 1 minute to form a high hardness film with a thickness of 3 μm. Comparative Example 2 2 parts of tetra-n-butyl titanate was dissolved in 98 parts of n-hexane and applied to a 50μ thick polyethylene terephthalate biaxially stretched film using a gravure coater, and heated at 130°C for 30 seconds to form a thin, uniform coating on the film. A film was formed. The coating amount was 0.2 g/m ² . The coating composition prepared in Reference Example 1 was applied onto this coating film using a gravure coater and heated at 160° C. for 1 minute to form a highly hard coating film with a thickness of 3 μm. Comparative example 3 80 parts of pentaerythritol tetraacrylate
1.6-20 parts of hexanediol diacrylate to 150 parts
1 part of methyl cellosolve was dissolved in 3 parts of benzoyl peroxide, and the mixture was coated on a 50μ thick polyethylene terephthalate biaxially stretched film using a gravure coater, and heated at 160°C for 1 minute to form a 3μ thick film.
A highly hard coating was formed. The results of Example 1 and Comparative Examples 1 to 3 are shown in Table 1. 【table】

Claims (1)

[Claims] 1. An isocyanate group-containing compound is applied to the surface of a synthetic resin molded product in a solid content of 0.01 g/m ² to 2 g/m ²
The compound is coated and laminated to a thickness of
A cured product of a compound containing three or more acryloyloxy groups and/or methacryloyloxy groups in the molecule, which is a laminate molded product coated and cured so that the film thickness after curing is 1 μ to 20 μ. 1. A laminate molded product characterized in that more than 98% by weight of the raw material to be formed is a compound based on an unsaturated monomer containing three or more methacryloyloxy groups and/or acryloyloxy groups. 2. The laminate molded product according to claim 1, wherein the synthetic resin molded product is a polyester film or sheet.