JP2001226601A - Glossy resin composition and molded product therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily obtain a resin molded product having high-grade pearl-glossy tone and expressing a deepness and high glossiness. SOLUTION: This glossy resin composition is obtained by compounding a glossy pigment into a thermoplastic resin. As the glossy pigment, scaly particles obtained by covering the surface of flaky glass with a metal oxide having a higher refractive index than the glass. The glossy resin molded product is obtained by injection molding of the glossy resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-grade pearly glossy resin composition useful for automobile parts, home electric appliances (including lighting fixtures such as lighting umbrellas), OA equipment, cosmetic containers, and miscellaneous goods. The present invention relates to an article and a glossy resin molded article obtained by molding the article.

[0002]

2. Description of the Related Art Conventionally, as a method for obtaining a resin molded product having a pearlescent appearance, a method of applying a paint containing a pearlescent pigment on the surface of the resin molded product, or a method of synthesizing with a pearlescent pigment. A method of melting and molding after mixing with a resin has been adopted. As a pearlescent pigment, pearl mica in which mica is coated with titanium dioxide has been generally used (JP-A-63-46266).

Japanese Unexamined Patent Publication (Kokai) No. 62-187770 describes an ultraviolet shielding pigment obtained by coating flaky glass with fine titanium dioxide. However, the pigment described in the publication has a coating amount of titanium dioxide. No pearlescent luster is exhibited.

[0004]

Conventionally, pearl mica, which is generally used as a pearly luster pigment, has a step on the surface because mica as a base material has cleavage nature by nature. Since the smoothness is poor and the glitter is weak, a product having sufficient gloss cannot be obtained.

[0005] Of the above-mentioned conventional methods, the method using coating has a problem that the cost is high because it takes time and effort.

[0006] On the other hand, a molded article using an existing pearlescent pigment has a problem in that it has a poor sense of depth compared to a painted article. In order to give deepness and stronger gloss by molding,
If the amount of the existing pearly luster pigment, for example, pearl mica, is increased, when pearl mica is added to the resin and kneaded, since it has cleavage properties, it is easily damaged, peeling and cracking occur, and as a result, As a result, the gloss is remarkably lost, and the inherent properties and physical properties of the resin are adversely affected.

The present invention solves the above-mentioned conventional problems and provides a glossy resin composition capable of easily obtaining a high-grade pearlescent resin molded product exhibiting a deep feeling and a high glossiness. An object of the present invention is to provide a glossy resin molded product obtained by molding the composition.

[0008]

The glossy resin composition according to the present invention is a glossy resin composition comprising a thermoplastic resin and a glossy pigment, wherein the glossy pigment covers the surface of the flaky glass with the flakes. It is a flaky particle coated with a metal oxide having a higher refractive index than the glass of the glass flakes.

The glossy resin composition of the present invention using flaky particles obtained by coating the surface of a flake-like glass with a metal oxide having a higher refractive index than that of the glass, as the gloss pigment, has a high luster. The feeling is remarkably superior to the brilliant feeling of the glossy resin composition using the conventional gloss pigment, and has a shining and deep feeling, that is, from a group of particles dispersed in the resin. It is possible to obtain a beautiful pearly-gloss molded article with rich gloss and high quality, in which gloss pigment particles are observed three-dimensionally.

[0010] In addition, a metal oxide coating such as titanium dioxide can obtain various interference colors having a brilliant effect by changing the thickness of the layer. A glossy resin molded product that exhibits various colors from chromatic to chromatic and has excellent glitter is obtained.

The glossy resin molded article of the present invention is obtained by injection molding such a glossy resin composition.

The scaly particles of the gloss pigment used in the present invention are:
Average thickness 0.5 ~ 15μm, average particle size 10 ~ 600μ
m, the average shape ratio, that is, the ratio of the average thickness to the average particle size (average thickness / average particle size) is less than 1/9. ~ 0.8
It is preferable that a coating layer having a thickness of μm is formed.

[0013] The content of the gloss pigment in the glossy resin composition is from 0.05 to 100 parts by weight of the thermoplastic resin.
It is preferably 10 parts by weight.

[0014]

Embodiments of the present invention will be described below in detail.

First, the gloss pigment according to the present invention will be described.

The luster pigment used in the present invention is a scale-like particle obtained by coating the surface of a flake-like glass with a metal oxide having a higher refractive index than glass (hereinafter referred to as "high-refractive-index metal oxide"). In other words, it is a flaky particle in which flake glass is used as a base material (core portion) and the surface thereof is provided with a coating layer of a high refractive index metal oxide.

Here, examples of the high refractive index metal oxide include anatase type titanium dioxide, rutile type titanium dioxide, zirconium dioxide, iron oxide and the like.
In particular, because it is practical in terms of cost, quality, etc., anatase type titanium dioxide or rutile type titanium dioxide,
Particularly, rutile type titanium dioxide is preferable.

The flake glass at the core is scale-like glass particles whose size is average particle size (longitudinal dimension).
Is preferably 10 to 600 μm, the average thickness is 0.5 to 15 μm, and the average shape ratio is less than 1/9.

If the average particle size is less than 10 μm, the glossiness is weak, and it is difficult to obtain a deep, high-grade pearly luster. There is no point in increasing the size. Further, those having an average thickness of less than 0.5 μm are easily crushed, while if the average thickness exceeds 15 μm or the average shape ratio becomes 1/9 or more, the number of particles per charged weight of the flake glass is reduced. Due to the reduction, the glitter effect is reduced, resulting in a loss of good pearlescent appearance. The glass composition of the flake glass is not particularly limited, and is mainly composed of SiO ₂ ,
Those containing a small amount of l ₂ O ₃ , CaO, B ₂ O ₃ and other components are exemplified.

The refractive index of such a glass flake is usually about 1.5 to 1.6, and the high refractive index metal oxide coating the surface of the glass flake has a refractive index of 2.0.
A range of about to 3.0 is preferable. The refractive index of anatase type titanium dioxide is about 2.5, the refractive index of rutile type titanium dioxide is about 2.7, and the refractive index of zirconium dioxide is about 2.1.

As a method of coating the surface of such a flake glass with a metal oxide having a high refractive index, for example, anatase or rutile type titanium dioxide, a sol-gel method and a liquid phase method are known. For example, Japanese Patent Application Laid-Open No. 9-176515 describes that a metal oxide-coated flake glass having an average shape ratio (average thickness / average particle size) of 1/9 to 1 and an average particle size of 25 to 500 μm can be obtained by a sol-gel method. Have been.
U.S. Pat. No. 5,753,371 discloses that, as an example of the liquid phase method, flake glass having a C glass composition is dispersed in an acidic aqueous solution, and ferric chloride and zinc chloride or tin chloride are added thereto, followed by stirring. While adjusting the pH, a titanium tetrachloride (TiCl ₄ ) aqueous solution is poured, and when a predetermined interference color is reached, the reaction is terminated, and the mixture is filtered, washed with water, and then heated and calcined at a predetermined temperature to coat the metal oxide. A method for obtaining flaked glass is described.

The present inventors have disclosed in US Pat.
By further developing the method described in Japanese Patent Laid-Open No. 1-2005, the following method capable of uniformly and stably coating a high refractive index metal hydroxide film without unevenness has been developed.

First, as a pretreatment, a flaky glass is surface-treated with tin chloride in an aqueous hydrochloric acid solution.
Treat with hexachloroplatinic acid. Next, this flaky glass is added to a hydrochloric acid aqueous solution adjusted to a pH of 1.3 or less, for example, about 1.0, and the temperature of the slurry liquid is reduced to 55-8.
The temperature is raised to 5 ° C., for example, 75 ° C., to adjust the pH to 0.5 to 1.3.
While adjusting the pH, an aqueous solution of TiCl ₄ is added and reacted until a predetermined interference color is reached. Then, the reaction product is filtered, washed with water, and then heated and calcined at a predetermined temperature, for example, 600 ° C. According to this method, US Pat.
The rutile-type titanium dioxide coating can be formed more uniformly and more stably without unevenness than the method described in JP-A-53371. Although the details of the reason why such an excellent rutile-type titanium dioxide film is formed by this method are not clear, in this method, platinum adheres to the surface of the flake glass, and the action of this platinum causes It is considered that the adhesion of the metal oxide is promoted and a uniform high-refractive-index metal oxide film without spots is formed.

The coating amount of the high-refractive-index metal oxide varies depending on the type of the high-refractive-index metal oxide, the required degree of glitter, the desired interference color, and the like.
Preferably, the thickness is 0.8 μm. If the thickness is excessively small, sufficient gloss cannot be obtained, and if the thickness is excessively large, economic efficiency is impaired.

When the thickness of the metal oxide coating layer is changed, the coating layer gradually changes from an achromatic color to a chromatic color as the thickness increases. For example, in the case of flaky glass coated with rutile-type titanium dioxide, a thickness of 0.05
In the vicinity of μm, both the reflected light and the transmitted light were silver, but when the thickness was increased to about 0.14 μm, the reflected light was reddish purple, the transmitted light was blue-green, and the thickness was further reduced to about 0.2 μm. Then, the reflected light changes to yellow-green and the transmitted light changes to red.
The hues of the reflected light and the transmitted light are caused by light interference phenomena, but because the reflected light can prevent light scattering due to the smoothness of the glass surface, both are clearer than mica having irregularities on the surface. And a high brilliancy can be obtained.

The purity of the high refractive index metal oxide such as titanium dioxide to be coated is preferably high, but it is preferably 96 to 99%.
To the extent, impurities containing impurities such as SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , and moisture may be used.

The gloss pigment made of flake glass coated with such a metal oxide can be used as it is. However, in order to improve the chemical resistance, for example, the surface is coated with a SiO ₂ film, Coating agent may be coated and used to enhance kneading with resin,
Providing such a coating film is effective for the present invention.

In the present invention, as the thermoplastic resin,
There is no particular limitation, for example, polyethylene, polypropylene, ethylene-propylene copolymer, polymethylpentene, polystyrene, ABS (acrylonitrile butadiene styrene) resin, AS (acrylonitrile styrene) resin, AES (acrylonitrile EPDM styrene) resin, acrylic resin, methacrylic resin , Polyamide, polyethylene terephthalate, polybutylene terephthalate, polyimide, polyarylate, polyacetal, polycarbonate, polyphenylene ether, polysulfone, polyphenylene sulfide, polyether sulfone, polybutadiene, and the like, or copolymers, mixtures, and modified products of these polymers. Can be In particular, highly transparent resins such as acrylic resin, methacrylic resin, polystyrene, AS resin, and polycarbonate are preferable.

In the present invention, if the amount of the above-mentioned gloss pigment is excessively small, it becomes difficult to obtain a high-quality pearly luster with high gloss and depth, and if it is excessively large, it adversely affects physical properties and the like. Therefore, the gloss pigment is preferably blended in a ratio of 0.05 to 10 parts by weight with respect to 100 parts by weight of the thermoplastic resin.

The glossy resin composition of the present invention contains a plasticizer, a stabilizer, an ultraviolet absorber, a flame retardant, and other property improvers, if necessary, in addition to the thermoplastic resin and the gloss pigment described above. May be.

If necessary, one or more selected from color pigments, other metallic pigments (eg, aluminum pigments, iron oxide pigments, etc.), interference color pigments (eg, mica coated with metal oxides) or Two or more kinds may be blended so as not to impair the glitteriness based on the gloss pigment.

The glossy resin composition of the present invention can be produced by mixing its constituent materials at a predetermined ratio, for example, using a tumbler, a Nauter mixer, a blender, an extruder, or the like.

Then, using the glossy resin composition,
By performing injection molding with an injection molding machine according to a conventional method, a high-quality pearly glossy molded product having a rich glossy depth can be obtained, and the obtained glossy resin molded product can be used for automobile parts and various containers. OA equipment, home appliances (including lighting fixtures such as lighting umbrellas), and miscellaneous goods.

[0034]

The present invention will be described more specifically below with reference to examples and comparative examples. In the following, “parts” and “%” indicate “parts by weight” and “% by weight”, respectively.

The specifications of the gloss pigment used in the examples and comparative examples are as follows.

[0036]

[Table 1]

Example 1 2 parts by weight of metashine RCFSX-5090RS (8073) based on 100 parts by weight of a bisphenol A type polycarbonate resin having the following structure (Idemitsu Carbonate "General grade A-2500" manufactured by Idemitsu Petrochemical Co., Ltd.) Was added and mixed, and a cylinder temperature of 2 was set using an extruder ("VS-30" manufactured by Tanabe Plastic Machinery Co., Ltd.).
Extruded at 90 ° C and pelletized. This pellet is
After drying at 20 ° C. for 5 hours, a flat plate (85 mm × 75 mm × 3 mm) was injection molded by an injection molding machine (“Promat 80/40” manufactured by Sumitomo Heavy Industries, Ltd.) under the following molding conditions.

[0038]

Embedded image

[Injection molding conditions] Cylinder temperature: Zone No. 1 = 290 ° C. Zone No. 2 = 305 ° C. Zone No. 3 = 310 ° C. Zone No. 4 = 300 ° C. Zone No. 5 = 300 ° C Mold temperature: 100 ° C Filling pressure: 60kg / cm²  Screw rotation speed: 150 rpm As a result of visual observation of the obtained molded article under natural light,
The reflected light from the body has a strong silver color, and is dull and foreign
A beautiful outside with a deep sparkle and a brilliant gloss
I got a view.

Examples 2 to 5, Comparative Example 1 A molded article was obtained in the same manner as in Example 1 except that the glossy pigments shown in Table 1 were used in the amounts shown in Table 2, and the appearance of the molded articles was observed. Are shown in Table 2 together with the results of Example 1.

Examples 6, 7 Polystyrene resin ("Dialex" manufactured by Mitsubishi Chemical Corporation)
 HF-77 ") 100 parts by weight of glossy face shown in Table 1
After adding and mixing 2 parts by weight of the mixture, the injection molding machine (Sumitomo Heavy Industries, Ltd.)
According to “Promat 80/40” manufactured by Machine Industry Co., Ltd.)
Inject flat plate (85mm x 75mm x 3mm) under molding conditions
Table 2 shows the observation results of the appearance of the molded article obtained by molding.
Was. [Injection molding conditions] Cylinder temperature: Zone No. 1 = 210 ° C. Zone No. 2 = 220 ° C. Zone No. 3 = 225 ° C. Zone No. 4 = 230 ° C. Zone No. 5 = 220 ° C Mold temperature: 50 ° C Maximum filling pressure: 22 kg / cm²  Screw rotation speed: 160 rpm

[0042]

[Table 2]

As is clear from Table 2, according to the present invention, there is no dullness, excellent three-dimensional appearance, and
It can be seen that a beautiful glossy resin molded product can be obtained.

[0044]

As described in detail above, according to the glossy resin composition of the present invention and its molded product, a high-grade pearly glossy resin molded product having a deep feeling and strong gloss can be easily obtained. . ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide high-quality and highly decorative products such as automobile parts, various containers, home appliances (including lighting fixtures such as lighting umbrellas), OA equipment, and miscellaneous goods. it can.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 4F071 AA12 AA15 AA15X AA20 AA20X AA21 AA22 AA22X AA31 AA34X AA45 AA46 AA50 AA51 AA54 AA60 AA77 AA84 AB17 AB28 AD05 AE09 AF31 AH09 AH11 BC01 BB BB BB BB BB BC BC031 BC061 BG041 BG051 BL011 BN061 BN151 BP021 CB001 CF061 CF071 CF161 CG001 CH071 CL001 CM041 CN011 CN031 DE097 DE117 DE137 DL006 FA016 FB076 FD096 GG01 GN00 GQ00

Claims (5)

[Claims] 1. A glossy resin composition comprising a thermoplastic resin and a glossy pigment, wherein the glossy pigment has a higher refractive index on the surface of the flaked glass than on the glass of the flaked glass. A glossy resin composition characterized by being scale-like particles coated with: 2. The scaly particles according to claim 1, wherein the average thickness is 0.5 to 15 μm and the average particle size is 10 to 600 μm.
And a coating layer of the metal oxide having a thickness of 0.03 to 0.8 μm is formed on the surface of flake glass having an average shape ratio (average thickness / average particle size) of less than 1/9. A glossy resin composition comprising: 3. The method according to claim 1, wherein the content of the gloss pigment is 0.05 to 100 parts by weight of the thermoplastic resin.
A glossy resin composition comprising 10 parts by weight. 4. The glossy resin composition according to claim 1, which is a resin composition for injection molding. 5. A glossy resin molded product obtained by injection molding the glossy resin composition according to claim 1.