JPS5952783A - Outside case for timepiece - Google Patents

Abstract

PURPOSE:To provide a case with superior surface hardness, wear resistance, chemical resistance, corrosion resistance, weather resistance, etc., by coating a case surface with a mixture which contains a specified compound, heating it for cross-link curing, to form a film. CONSTITUTION:One kind of the compounds among a silicide containing an epoxy group or its partial hydrolysate shown by a formula 1, a silicide or its partial hydrolysate shown by a formula 2, a halide, an oxyhalide, or a metallic alcoholate of the atoms in the group IV of the periodic table, and a metallic chelated compound having a ligand is used. Then, 88pts. gamma glycidoxy propyl trimethoxy silane and 80pts. tetramethoxy silane are dissolved in 100pts. isopropyl alcohol and a 50pts. solution of 0.05N hydrochloric acid is added and stirred for partial hydrolysis; and aging is carried out and 0.3pts. Sncl2 and a silicone block copolymer are added to prepare a treating solution, which is coated over the case and baked to form a cured film.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to metals. The present invention relates to exterior parts for watches manufactured from plastics, wood, etc., which have a crosslinked cured film that has improved surface hardness (9), abrasion resistance, chemical resistance (9), corrosion resistance, weather resistance, etc.

The part is a case for a mobile watch (hereinafter abbreviated as case).
Taking this as a typical example, cases have conventionally been made of metal, plastic, and some wood, processed into a case shape, and finished with plating or the like. However, the abrasion resistance of each surface was poor, and the initial aesthetic appearance could not be maintained for a long period of time. In recent years, cases made of cemented carbide or intermetallic compounds with improved fixation points, and cases in which the surface of the case is coated with cemented carbide or intermetallic compounds using P'VD or OVD methods have become popular on the market. However, all of them have color tone limitations and are expensive, so they are only used in a limited range. In addition, the former especially has drawbacks such as limited shape and poor impact resistance.

The present invention improves the above-mentioned drawbacks, and provides a case with excellent surface hardness, wear resistance, and chemical resistance.

It has been successfully coated with a specific cross-linked cured film that provides corrosion resistance, weather resistance, etc. Here, the present invention uses materials conventionally used (metals, plastics) as a case used as a base material.

Since it can be applied to all cases made of wood (wood, etc.) and surface treated (plated, painted, etc.), there are of course no restrictions on the material, shape, color tone, etc. of the case, and furthermore, the crosslinked cured film has the ability to be dyed. By imparting the ability to dye, the degree of freedom in tone can be extended to a range that cannot be obtained in the conventional case.In other words, the present invention , R1 is an organic group having an epoxy group, R2 is hydrogen or a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group, α is 1, 2, b is 0.1. an epoxy group-containing silicon compound or a partial hydrolyzate thereof represented by α+b≦2.

CB) General formula (2), R3cmSi-X4-,
(In the formula, R3 is hydrogen, a hydrocarbon group having 1 to 4' carbon atoms,
A silicon compound or a partial hydrolyzate thereof, which represents a mercapto group or an organic group having chlorine, or a hydrolyzable group, and C is 0 to 2.

(0) /% rogenide of atoms of group Ⅰ of the periodic table.

At least one compound of an oxyhalide, a metal alcoholade, or a metal chelate compound having a ligand.

A case characterized by having a coating obtained by uniformly coating the surface of a ready-made case with a mixture containing at least the above (A)I (B)#Co), and then crosslinking and curing by heating. Representative examples of the epoxy group-containing silicon compound represented by the general formula (1) are shown below.

β-glycidoxyethyltrimethoxysilane γ-glycidoxypropyltrimethoxysilane bis(glycidoxymethyl)dimethoxysilane 3.4-epoxycyclohexylmethyltrimethoxysilane 3.4-epoxycyclohexylmethyltriethoxysilane, etc. be.

Further, typical examples of the silicon compound represented by the general formula (2) are shown below.

Methyltrimethoxysilane, methyltriethoxysilane, mercaptopropyltrimethoxysilane, chloroprobyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, and the like. The silicon compounds of general formulas (1) and (2) are hydrolyzed individually or after being mixed, if necessary.

Hydrolysis is carried out by adding pure water or an acidic aqueous solution such as hydrochloric acid or sulfuric acid and stirring. Hydrolyzed K11Jl
Since alcohols, alkoxy alcohols, organic carboxylic acids, etc. are produced, it is possible to hydrolyze without a solvent, but it is also possible to hydrolyze after adding an appropriate solvent. Depending on the purpose, it is also possible to use the product after hydrolyzing it without a solvent and removing an appropriate amount of the resulting alcohol, alkoxy alcohol, organic carboxylic acid, water, etc. by heating and/or under reduced pressure. It is also possible to substantially replace the solvent by adding a suitable solvent to it. Solvents include alcohols, cellosolves, ethers, and esters.

Carboxylic acids, halogenated hydrocarbons, aromatics, ketones, etc. can be used alone or in a mixed solvent. Furthermore, if necessary, various surfactants and flow control agents may be used to improve the appearance of the crosslinked cured film. Examples of hydrolyzable groups include alkoxy groups, acyloxy groups, amide groups, and aminooxy groups.

Next, regarding the curing catalyst, conventionally Lewis acids such as BF, Brønsted acids such as hydrochloric acid and sulfuric acid are used.

Ammonium salts such as ammonium chloride and ammonium perchlorate. Carbonates such as sodium carbonate are known, but when used for the above (A) w (B) component),
The resulting crosslinked cured film has insufficient hardness and poor abrasion resistance, chemical resistance, etc., and cannot be used practically as a curing catalyst. In order to achieve the object of the present invention, a 7-halogenide, an oxyno-logenide, a metal alcoholade, or a metal chelate compound having a ligand of a metal element in group Ⅰ of the periodic table is essential as a catalyst. Examples include stannous chloride, stannic chloride, tin bromide, zinc chloride, titanium tetrachloride,
Titanium bromide. Thallium bromide, germanium chloride, phenium chloride, lead chloride, etc., tin oxychloride, niobium oxychloride, aluminum oxychloride, etc., and metal alcoholade monomers such as tetrabutoxytitanium, tetrabutoxyzirconium, pentaethoxytantalum, tetrabutoxyhafnium, etc. Effective are chelate compounds or multimers, and furthermore, chelate compounds having a ligand such as acetylacetone, methyl acetoacetate, or lactic acid. The amount of this curing catalyst used is 0.01 to 10% of the total amount of components (A) and 9 and (B).
If it is less than 0.01 part by weight, the hardness will be insufficient, requiring a long time and high temperature for curing, and if it is more than 10 parts by weight, the impact resistance of the crosslinked cured film will be reduced. The hardness decreases and cracks are more likely to occur.

In addition, (A) 9 (B) component, (A') component is 20 to 9
If component (A) is less than 20 parts by weight, the resulting film will have poor impact resistance, and if it is more than 90 parts by weight, Poor hardness and wear resistance.

In addition, for the purpose of imparting dyeability to the cured film, the above (A) #
(B)# In addition to component (0), it is possible to add various monomers and polymers having polyfunctional groups, and the obtained cured film can be easily dyed with various disperse dyes. Typical examples of the monomers and polymers include ethylene glycol diglycidyl ether, polyethylene A glycol diglycidyl ether, glycerin diglycidyl ether, glycidyl ether of bisphenol A, diglycidyl ethers of aromatic and alicyclic compounds, and Polyhydric alcohols and hydroxycelluloses.

Hydroxyacrylics, etc., and these include (A), (
B) It may be added in an amount of 20 to 60 parts by weight per 100 parts of the total weight of the components. If it is less than 20 parts by weight, the ability to dye is poor;
If the amount exceeds 1 part by weight, the hardness and abrasion resistance of the resulting coating will be reduced.

The treatment liquid composed of the above components is applied to the case by a known method such as spraying, and heated at 80 to 250°C for 20 minutes to 3 hours to form a three-dimensional, dense crosslinked cured film on the case surface. to form. As described above, since the treatment liquid materials are inexpensive and the method is simple, a cured film can be formed at low cost. The thickness of the crosslinked cured film is preferably 1 to 50 μm,
If it is less than 1 μm, the properties such as wear resistance cannot be fully exhibited, and if it is more than 50 μm, the smoothness of the coating gradually deteriorates.

The resulting crosslinked cured film has excellent transparency and smoothness, and does not impair the finish, color tone, or other appearance of the case. In addition, as mentioned above, the coating is dense, its surface hardness is high, and it has excellent wear resistance and
Shows excellent properties such as chemical resistance, weather resistance, and corrosion resistance.

I have talked about the case above, but the dial.

The present invention can be applied to all exterior parts for watches such as bands. Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto. Further, parts in the examples indicate parts by weight.

The obtained exterior parts were evaluated using the method shown below.

Adhesion: Bend the exterior part to an angle of 90 degrees and examine the state of the coating at the bending point.

Abrasion resistance: Apply a load of 5001 to the exterior part and press it against the cowhide surface, and after 15000 recovery wear with a stroke of 6 cm, the worn surface is examined.

Corrosion resistance: After immersing the exterior part in artificial sweat at a liquid temperature of 40°C for 48 hours, the degree of discoloration and corrosion of the exterior part and the state of the coating are examined.

Weather resistance: The exterior part is left in a fetometer tester for 200 hours, and the exterior appearance of the exterior part surface and film, such as discoloration and fading, is examined.

Pinhole check: The exterior parts are exposed to a concentrated nitric acid atmosphere (at room temperature) for 1 hour, and the presence or absence of pinholes is examined based on the degree of corrosion.

Chemical resistance: The exterior parts can be exposed to commonly used chemicals such as trichloride, ethyl alcohol, thinner, and benzine at room temperature.
After soaking for a period of time, check for changes in appearance.

Impact resistance (for cases and bands): After repeatedly dropping the exterior part 5 times from a height of 1rIL onto a seed plate fixed to concrete, check whether there are any cracks or dents in the coating at the impact point. investigate.

Example 1 A case is manufactured using a brass plate by a normal case processing method such as pressing, cutting, and polishing. The case was thoroughly cleaned, copper strike plating (film thickness: 0.1 μm), nickel base plating (film thickness: approx. 3 μfrL), and black Or plating (gamma glycide in 100 parts of isopropyl alcohol according to the film thickness method) were applied as the final finishing plating. 88 parts of xyprobyltrimethoxysilane.

80 parts of tetramethoxysilane was dissolved, 50 parts of 0.05N aqueous hydrochloric acid solution was added, and the mixture was stirred at room temperature for 2 hours to perform partial hydrolysis, followed by aging at room temperature for 2 hours. After that, 5n0
7. 0.3 parts of silicone block copolymer Y70
A small amount of 06 (manufactured by Nippon Unitika) was added and stirred to prepare a treatment liquid.

The treatment liquid was applied to the case by a spray method. 60°
After pre-baking at C for 20 minutes, the temperature was gradually raised to 180°C.
Two pieces were fired for 1 hour, and then slowly cooled to room temperature.

The obtained cured film was transparent and had a film thickness of 5 μm.

Also, the surface was extremely smooth, and there was no change in color tone of the black Or plating color.

As a result of the quality evaluation, the case coated with the cured film met all the criteria and showed good results. As a comparative product, a case not covered with the cured film was examined, and in the abrasion resistance test, the brass base material was exposed on the worn surface after 1 ooo reciprocating abrasion.

Example 2 A case was manufactured using a nickel silver plate in the same process as in Example 1. Thoroughly wash the case and apply copper strike plating (film thickness: 0.1 μm) and nickel base plating (film thickness: approx. 4 μm).
The final finish 18 was gold plating (film thickness 6 μ%).

A cured film was formed using the treatment solution of Example 1 and the same treatment method. The cured film was extremely transparent, had a smooth surface, and had a film thickness of 3 μm. Due to the formation of a hardened film, the beauty of the gold-plated color was not impaired, and it was difficult to visually identify the presence of a hardened film.The quality evaluation results showed good results in all items. In particular, in terms of wear resistance, the case with a hardened film has a long lifespan of 40,000 times, compared to 16,000 times for a conventional case without a hardened film, maintaining the beauty of gold plating for a longer period of time. It became possible to do.

In addition, other items such as corrosion resistance and chemical resistance fully satisfied the specifications, and exhibited characteristics that were more than twice as good as conventional products that did not form a cured film. Also, in the impact resistance and adhesion tests, no peeling of the cured film was observed after the tests.

Example 6 A case was manufactured by injection molding using polycarbonate resin.

To 100 parts of isopropyl alcohol, 60 parts of γ-glycidoxypropyltrimethoxysilane, 50 parts of tetraethoxysilane, and 65 parts of 1.6 hexanediyl diglycidyl ether were added to 100 parts of isopropyl alcohol. The mixture was stirred at room temperature for 2 hours to perform partial hydrolysis, and further aged at room temperature for 20 hours. Then, 0.2 parts of tin oxychloride and silicone block copolymer L were added.
A small amount of 7604 (Nippon Unicar product) was added and stirred to prepare a treatment liquid.

The above treatment liquid was applied to the case by a spray method, and
After preliminary firing at 120°C for 30 minutes, main firing was performed at 120°C for 2 hours, and then slowly cooled to room temperature. The film thickness was 8 μm.

As a result of quality evaluation, it showed excellent properties, especially in terms of chemical resistance. Trichlene, ethyl alcohol.

After checking the appearance of the case after immersing it in thinner and benzine for 3 minutes (the metal case was immersed for 1 hour as described above), it was found that the case of the conventional product without a hardened film had a rough white surface and part of the surface was dissolved. However, in the product of the present invention, no change in appearance was observed at all.

In terms of abrasion resistance, whereas the conventional product becomes scratched after a few wears, the present invention starts to get scratches after about 1000 wears. Other properties such as adhesion and weather resistance were also good.

Next, the polycarbonate case coated with the above-mentioned cured film can also be dyed. After adding disperse dye, Miketon Polyester Red 4BF (product of Mitsui Toatsu Co., Ltd.) 22 to 1 ton of water, Ravisol (product of NOF Co., Ltd.) 21 was added, stirred thoroughly, and then heated to 80°C. When the case of the present invention was immersed in the solution for 5 minutes, it was dyed pale red.

After dyeing, no deterioration in the properties of the cured film was observed, and no fading or discoloration was observed in the weather resistance test.

In this way, one of the features of the product of the present invention is that it can freely create color tones in the final process, and in combination with the finish pattern and color tone of the base of the cured film, it can be used in an unprecedented variety of colors. This allows us to meet the needs of the market more than ever before.

that's all Applicant: Suwa Seikosha Co., Ltd. Agent Patent Attorney Mogami −Required

Claims (1)

[Claims] is an organic group having an epoxy group, R2 is hydrogen or a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group, α is 1, 2, b is 0, 1, an epoxy group-containing silicon compound or a partial hydrolyzate thereof represented by α+b≦2. (B) General formula (2) R"c-Si -X4-c (wherein R3 is hydrogen, a hydrocarbon group having 1 to 4 carbon atoms, a mercapto group or an organic group having chlorine, or a hydrolyzable (C is 0 to 2. 1. An exterior part for a watch, characterized by being coated and cross-linked with a mixture containing at least one metal chelate compound having a metal chelate compound.