JP3298247B2 - Synthetic resin molded article with improved surface properties and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to surface hardness, abrasion resistance,
The present invention relates to a synthetic resin molded article having improved surface properties such as scratch resistance, weather resistance, stain resistance and transparency, and a method for producing the same.

[0002]

2. Description of the Related Art General-purpose synthetic resins such as polycarbonate resin, vinyl chloride resin, methacrylic resin, AS resin, ABS resin, polypropylene resin, polyester resin, nylon resin, polyacetal resin, polystyrene resin, noryl resin, and PBT resin have strength, Shows excellent properties such as water resistance, cold resistance, weather resistance, etc., and is widely used as a molding material.However, it has low surface hardness and is easily scratched. There is an easy disadvantage. Further, when the contaminated surface is washed once, the smoothness of the surface is impaired, so that the transparency is reduced and the contamination resistance is further deteriorated.

As a method for improving these disadvantages, a method of coating the surface of a synthetic resin molded article with various coating materials has been proposed, but it is not always satisfactory. For example, as a typical method of a hard coat, a method of applying a (meth) acrylic acid ester and curing it with ultraviolet rays, and a method of applying a silicone monomer and curing it with heat are known. However, the former method has insufficient surface hardness, water resistance, weather resistance, etc., and the latter method cannot achieve reproducibility of performance unless applied in a completely humidified atmosphere, and the weather resistance is extremely unsatisfactory. In addition to these levels, the impact resistance is often significantly reduced.

[0004] In recent years, as the use of synthetic resin molded products has expanded in a wide range of fields such as home appliances, sporting goods, civil engineering, construction, and vehicles, there has been a strong demand for the improvement of the above surface properties.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to overcome the above-mentioned drawbacks of the conventional coated synthetic resin molded article, and to achieve surface hardness, abrasion resistance, abrasion resistance, weather resistance and weather resistance by a simple operation. It is an object of the present invention to provide a coated synthetic resin molded article having excellent surface properties such as contamination and a method for producing the same.

[0006]

Means for Solving the Problems In view of the problems of the prior art, the present inventors have conducted intensive studies on coating materials applied to the surface of a synthetic resin molded product, and as a result, have found that a coating composition capable of achieving the above object is obtained. The inventors have found that a resin molded product can be obtained, and have completed the present invention.

That is, the present invention relates to a polyorganosilsesquioxane wherein at least one of the side chain organic groups is a vinyl group or an organic group having a vinyl group as a substituent on the surface of the synthetic resin molded article. The present invention relates to a synthetic resin molded article having a coating layer comprising a copolymer resin of a polydialkylsiloxane having at least one vinyl substituent per molecule and a vinyl monomer or a cured product of a composition containing this resin.

[0008] The present invention also provides a synthetic resin molded product having a surface
A polyorganosilsesquioxane wherein at least one of the side chain organic groups is a vinyl group or an organic group having a vinyl group as a substituent, and a polydialkyl having at least one vinyl substituent per molecule. Coating a solution of a copolymer resin of siloxane and vinyl monomer or a composition containing this resin, and performing volatilization and three-dimensional curing of the solvent. It relates to a manufacturing method.

The synthetic resin constituting the synthetic resin molded article of the present invention includes polycarbonate resin, vinyl chloride resin,
General-purpose synthetic resins such as methacrylic resin, AS resin, ABS resin, polypropylene resin, polyester resin, nylon resin, polyacetal resin, polystyrene resin, noryl resin, and PBT resin are exemplified. In particular, the present invention relates to a polyorganosilsesquioxane wherein at least one of the side chain organic groups of the present invention is a vinyl group or an organic group having a vinyl group as a substituent, and at least one vinyl group per molecule. Not only is the coating layer made of a copolymer resin of a polydialkylsiloxane having a substituent and a vinyl monomer or a cured product of a composition containing this resin extremely high in transparency, but also by coating, Since transparency higher than that of the synthetic resin can be realized, it can be particularly effectively applied to a resin requiring transparency such as a polycarbonate resin, a vinyl chloride resin, a methacryl resin, an AS resin, and a polystyrene resin.

The polyorganosilsesquioxane of the present invention can be produced by hydrolyzing and co-condensing several kinds of corresponding trialkoxysilanes and / or trichlorosilanes.

In the present invention, the molecular weights of the polyorganosilsesquioxane and the polydialkylsiloxane are determined by the number average molecular weight measured using a gel permeation chromatography (GPC) apparatus and a standard molecular weight substance, respectively.
(Mn) is preferably about 500 to 10,000. The molecular weight distribution is preferably as narrow as possible, and Mw / Mn is preferably from 1 to 3. When the molecular weight distribution is widened, those having a high molecular weight become polyfunctional more than necessary, and are likely to gel during vinyl copolymerization.

Examples of trialkoxysilane and / or trichlorosilane having a vinyl group or an organic group having a vinyl group as a substituent include the following. Vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrichlorosilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrichlorosilane, γ- Acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane.

In the present invention, the number of vinyl groups per molecule of the polyorganosilsesquioxane or polydialkylsiloxane is preferably 1 to 2, and more preferably 1.3 to 1.8. If it is two or more, gelation tends to occur during vinyl copolymerization. If the number is less than one, the ratio of those not incorporated into the polymer at the time of vinyl copolymerization increases, and the adverse effects associated therewith cannot be avoided.

In the polyorganosilsesquioxane of the present invention, the side chain other than a vinyl group or an organic group having a vinyl group as a substituent is an alkyl group having 1 to 8 carbon atoms or a substituted or unsubstituted phenyl group. Containing 50% by mole or more of methyl groups,
Particularly preferred in terms of hardness and the like. Examples of the corresponding trialkoxysilane and / or trichlorosilane include the following. Methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrichlorosilane, ethyltrimethoxysilane, ethyltriethoxysilane, trichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenyltrichlorosilane, phenyltrimethoxysilane, Phenyltriethoxysilane.

The polydialkylsiloxane having at least one vinyl substituent per molecule used in the present invention has a vinyl substituent at a terminal and / or a side chain, and specific examples thereof include the following. Can be X-22-174D manufactured by Shin-Etsu Chemical Co., Ltd. If necessary, it may be induced by a polymer reaction. For example, polydimethylsiloxane having terminal hydroxyl groups (X-22-170B manufactured by Shin-Etsu Chemical Co., Ltd.) may be reacted with an unsaturated isocyanate such as isocyanateethyl methacrylate.

The hydroxyl group and / or the terminal of the side chain and / or the terminal of the polymethylsilsesquioxane having a vinyl group or an organic group having a vinyl group as a substituent used in the present invention.
Alternatively, it is also possible to further increase the stability of the vinyl copolymer resin having polymethylsilsesquioxane used in the present invention in the molecular structure by trimethylsilylation of the alkoxy group.

In the present invention, vinyl monomers which are copolymerized with a polyorganosilsesquioxane containing a vinyl group or an organic group having a vinyl group as a substituent and a polydialkylsiloxane having a vinyl substituent are as follows. Can be exemplified. Of course, the present invention is not limited to these exemplified monomers at all. Methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-methacrylic acid 2-
Acrylic acid or methacrylic acid such as ethylhexyl, lauryl acrylate, lauryl methacrylate, stearyl acrylate, stearyl methacrylate and the like, and one carbon atom
Esters with a monohydric alcohol of -22, styrene, vinyltoluene, α-methylstyrene, acrylonitrile,
Other vinyl monomers such as vinyl acetate and vinyl chloride.

In the present invention, in order to three-dimensionally cure the coating film, a vinyl monomer having the following crosslinkable reactive group can be copolymerized and used as a part of the vinyl monomer. Hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate,
Alcohol-containing vinyl monomers such as acrylic acid, methacrylic acid, itaconic acid, maleic anhydride, etc .; vinyl monomers containing epoxy groups such as glycidyl acrylate and glycidyl methacrylate; acrylamide, methacrylamide, N Amide group-containing vinyl monomers such as -methylolamide and N-methylolmethacrylamide; dimethylaminoethyl methacrylate, 2-diethylaminoethyl methacrylate,
Amine-based vinyl monomers such as tert-butylaminoethyl methacrylate; sulfonic acid groups such as vinylsulfonic acid and vinylsulfonyl chloride; and vinyl monomers containing chlorosulfonic acid groups; other mercapto groups and amide oxime groups;
Aldehyde group, acetylacetonate group-containing vinyl monomer, etc.

The content of the polyorganosilsesquioxane in the vinyl copolymer resin of the present invention is 1 to 50% by weight, preferably 2 to 40% by weight.
Modification such as weather resistance becomes insufficient, and it is too fragile, and the followability to substrate deformation is deteriorated. In addition, the polydialkylsiloxane is 1 to 40% by weight, preferably 2 to 30% by weight.
When the amount is too small, the ability to follow the deformation of the base material is deteriorated. When the amount is too large, hardness is not obtained and the stain resistance is lowered.
Further, the content of the vinyl monomer is from 10 to 98% by weight, preferably from 20 to 80% by weight. When the amount is too small, the coating properties deteriorate, and when the amount is too large, the weather resistance and stain resistance become low.

The molecular weight of the vinyl copolymer of the present invention is GPC
Is from 3,000 to 500,000, preferably from 10,000 to 100,000. If the molecular weight is less than this, the smoothness during coating is poor and the solvent resistance of the cured film is poor. On the other hand, if it is more than this, the viscosity becomes high and the coating workability is adversely affected.

In order to three-dimensionally cure the vinyl copolymer resin having a molecular structure of the polyorganosilsesquioxane and the polydialkylsiloxane of the present invention, it is necessary to react with the above-mentioned crosslinkable reactive group to form a crosslink. After coating as a composition with a suitable crosslinking agent, the composition can be cured under predetermined curing conditions. As the curing method, it is possible to use a method generally used such as room temperature curing, heat curing, photopolymerization, and in that case, an initiator, a catalyst, and an auxiliary agent suitable for each curing method are used in combination. Can accelerate curing.

Particularly, in the present invention, since heat curing can be performed, it is extremely convenient when photopolymerization or the like is inappropriate, and furthermore, the weather resistance and the like can be improved. The conditions for heat curing differ depending on the reaction mode, but are, for example, at about room temperature for 2-3 hours, at 80 ° C for 20 minutes, at 200 ° C.
And various conditions such as 60 seconds can be applied.

When coating the surface of a synthetic resin molded article with the resin or the resin composition as described above,
Various solvents can be used. Solvents include alcohols such as propanol and butanol, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ethers such as cellosolve acetate and methyl cellosolve, esters such as ethyl acetate and butyl acetate, and aromatics such as toluene and xylene. Group hydrocarbons and the like. Of course, these solvents may be used as a mixture of two or more.

In the present invention, as a method for coating the surface of a synthetic resin molded article with a solution of a copolymer resin of polyorganosilsesquioxane, polydialkylsiloxane and vinyl monomer or a composition containing this resin, A commonly used coating method such as spray coating, roll coating, dipping, and flow coating can be employed.

In the present invention, when a solution of the resin or the resin composition as described above is coated on the surface of a synthetic resin molded product, a product having good adhesion and transparency can be obtained by direct coating. Of course, in order to further improve the adhesiveness, or when there is whitening due to a solvent and the transparency is impaired, the surface of the synthetic resin molded product is subjected to a primer treatment in advance, and then coated with the resin solution of the present invention. Three-dimensional curing is also possible.

The copolymer resin of the polyorganosilsesquioxane, the polydialkylsiloxane and the vinyl monomer of the present invention includes an extender, a thickener, a color pigment, an ultraviolet absorber, an antioxidant, a leveling agent, It can also be used as a resin composition to which a foaming agent and the like are added.

The synthetic resin molded article with improved surface properties according to the present invention can be used in a wide variety of forms such as molding materials, sheets, films and the like. In addition, these uses
Extensive development can be expected in home appliances, civil engineering and construction applications, vehicles, machinery, etc.

[0028]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to the following Examples.
In addition, each physical property value in an Example was measured according to the following method.

[Surface hardness] It was measured according to JIS K5401 using a pencil scratch tester for paint. [Transparency] Using a haze meter, the light transmittance was measured according to JIS K7105.

[Weather Resistance] A carbon arc sunshine weather meter test was performed according to the provisions of JIS B7753. After 2,000 hours, the surface of the test specimen was observed and compared with that before the test to evaluate. The polymethylsilsesquioxane having a vinyl group used in the examples was synthesized as follows.

[Synthesis of methacryl-reactive polymethylsilsesquioxane] In a 2 liter flask equipped with a thermometer, a stirrer and a reflux condenser, 50 g (0.2 mol) of γ-methacryloxylpropyltrimethoxysilane, methyl Triethoxysilane 445 g (2.5 mol) Phenyltrimethoxysilane 20 g (0.1 mol) Acetone 200 g, hydrochloric acid 0.02
Mol, and 54 g (3 mol) of water.
The temperature was raised to 60 ° C. and maintained for 3 hours with stirring. continue
After raising the temperature to 70 ° C and reacting for 1 hour, 0.03 mol of KOH was added dropwise, and the reaction was further neutralized for 2 hours, washed with water and toluene, and then washed with a solvent and water using a rotary evaporator. After removal of these substances, a viscous liquid having a viscosity of 1450 cps at 25 ° C. was quantitatively obtained. The GPC curve of this was a single peak, and no residual peak derived from the monomer was observed. Therefore, the monomer is considered to be completely co-condensed, and the molar ratio of the side chain methyl group, γ-methacryloxypropyl group, and phenyl group is derived from the raw material molar ratio,
5: 2: 1. The molecular weight is determined by GPC.
(Mn) was 3,200. This is designated as polymer A-1.

[Synthesis of copolymer resin of polyorganosilsesquioxane, polydialkylsiloxane and vinyl monomer] A thermometer, a stirrer, and a reflux condenser were installed.
The following composition was placed in a liter flask, and reacted at 85 ° C. for 5 hours under reflux in a nitrogen stream.
The reaction rate by GPC was 97%. Polymer A-1 100 parts by weight One-terminal methacryl-modified polydimethylsiloxane (X-22-174D manufactured by Shin-Etsu Chemical) 40 parts by weight Methyl methacrylate 100 parts by weight Butyl methacrylate 55 parts by weight 2-ethylhexyl acrylate 45 parts by weight Hydroxy methacrylate 75 parts by weight of ethyl 10 parts by weight of t-butyl dodecanethiol 5 parts by weight of azobisisobutyronitrile 400 parts by weight of butyl acetate Polymer A-2 having a number average molecular weight of 23,000 and a weight average molecular weight of 95,000 was thus obtained.

Example 1 The following components were mixed uniformly, and a polycarbonate resin plate (
(5 mm thick) The surface was coated with a roll coater and then cured at 80 ° C. for 30 minutes. As a result, a 15 μm thick film was obtained which was extremely transparent and had good adhesion. Polymer A-2 40 parts by weight Polyisocyanurate (N-3500 manufactured by Sumitomo Bayer Co.) 10 parts by weight butyl acetate 50 parts by weight Table 1 shows the data of surface pencil hardness, light transmittance and weather resistance of this cured film.

Example 2 In place of the polycarbonate resin plate of Example 1, the surface of the methacrylic resin vacuum-formed body was spray-coated with the resin solution of Example 1 and then cured at 80 ° C. for 30 minutes. A film having a good adhesion and a thickness of 14 microns was obtained. The surface pencil hardness of this cured film,
Table 1 shows data of light transmittance and weather resistance.

[0035]

[Table 1]

Example 3 A polyester resin film was prepared by uniformly mixing the following components:
(200 μm thick) After dip coating on the surface, it was cured at 160 ° C. for 3 minutes to obtain a 7 μm thick film which was extremely transparent and had good adhesion. Polymer A-2 42 parts by weight Butylated melamine 18 parts by weight Butyl acetate 50 parts by weight Paratoluenesulfonic acid 0.2 parts by weight This cured film shows extremely excellent magic stain resistance, and the mark marked with red magic is 24 hours. Later, it could be completely wiped off by simply rubbing with tissue paper.

[0037]

According to the present invention, a synthetic resin molded article having a surface coated with a coating according to the present invention has excellent surface properties which are difficult to realize with a synthetic resin molded article, such as surface hardness, abrasion resistance, scratch resistance, and the like. Since it has weather resistance, stain resistance, and transparency, it can be expected to be applied to a wide range of applications in a wide range of fields such as home electric appliances, sporting goods, civil engineering, architecture, and vehicles.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-51424 (JP, A) JP-A-4-33936 (JP, A) JP-A-6-256445 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C08J 7/04 C08F 299/08 C09D 183/00

Claims (2)

(57) [Claims] 1. A polyorganosilsesquioxane wherein at least one of the side chain organic groups is a vinyl group or an organic group having a vinyl group as a substituent, and at least one vinyl substituent per molecule. What is claimed is: 1. A synthetic resin molded article having a coating layer comprising a copolymer resin of a polydialkylsiloxane and a vinyl monomer as described above or a cured product of a composition containing the resin. 2. A polyorganosilsesquioxane in which at least one of the side chain organic groups is a vinyl group or an organic group having a vinyl group as a substituent is provided on the surface of the synthetic resin molded article. Coating a solution of a copolymer resin of a polydialkylsiloxane having at least one vinyl substituent per molecule with a vinyl monomer or a composition containing this resin, and performing volatilization of the solvent and three-dimensional curing. A method for producing a synthetic resin molded product.