JPS5998842A - Manufacture of reflecting mirror - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a reflecting mirror for a lighting device.

Reflectors for lighting equipment with HID light sources, such as outdoor sports lighting, factory lighting, road lighting, square lighting, etc., have been manufactured by the following method. The first method is to separately polish the metal base material, electrolytically polish it, and then perform alumite processing.

This method requires time and effort for separate cloth polishing, uses various harmful substances in electrolytic polishing, requires measures to prevent pollution, which increases costs, and has the disadvantage that the resulting reflector lacks corrosion resistance. There is. The second and third methods are methods in which an organic paint coating or an inorganic paint coating is applied in place of the alumite treatment in the first method. These methods, like the first method, have the disadvantages of separate cloth polishing and electrolytic polishing, and the resulting reflector lacks heat resistance or corrosion resistance (the inorganic protective coating is generally based on silicate). Because of this, it has the disadvantage of being susceptible to whitening due to moisture. A fourth method is to apply an organic base coat to the substrate followed by A1 deposition and a further organic paint coating. This method requires an enormous amount of money to treat the organic solvent, and the resulting reflective mirror lacks heat resistance (silicone paints have good heat resistance, but their high cost limits their use). have.

This invention was made in view of the above circumstances, and the following component (A) is applied to the surface of the base material in an amount of 30 to 7 on a solid content basis.
0% by weight and 30 to 70% by weight of component (B) based on solid content.
A base layer is formed using a water-soluble thermosetting acrylic paint containing 0 to 35% by weight of component (C), and a glittering metal film is formed on this base layer by vapor deposition. The feature is that the reflective mirror is obtained by forming an oxide protective film on the mirror by vapor deposition.

(A) A main component consisting of a water-soluble resin obtained by water-solubilizing a copolymer of an α,β-unsaturated alcohol, an α,β-unsaturated carboxylic acid, and a vinyl monomer copolymerizable with these by alkali neutralization.

(B) Alkyl etherified melamine resin.

Alkyl etherified urea resin and Alkyl etherified Henzoguanamine at least one selected from the group consisting of resins It is also a kind of water-soluble alkyl etherification A hardening agent made of mino resin.

(C) At least one of an extender pigment and titanium oxide with a particle size of 15 μm or less.

That is, according to the present invention, an increase in cost can be avoided because separate cloth polishing and electrolytic polishing are not required, and the base layer,
Excellent adhesion due to the combination of bright metal film and oxide protective film forming a mirror surface.

A reflective mirror with high heat resistance, corrosion resistance, and specularity (reflectance) can be provided. Furthermore, since the present invention uses a water-soluble paint for the base layer, it has the advantage that it does not require a huge amount of expense for anti-pollution measures.

Next, this invention will be explained in detail.

The base material used for the reflecting mirror according to the present invention includes At,
A plate material made of A1 alloy, Fe, or Fe alloy that is finished into a predetermined reflecting mirror shape by a forming method such as press forming or spatula drawing is used.

The paint used for the base layer includes the above component (A) and (
A water-soluble thermosetting acrylic paint containing component B) and component (C) in a predetermined ratio is used, and is used after dissolving 7g in a water-based solvent such as water-ethylene glycol monobutyl ether solvent. be done. Here, α in the component (A).

The β-unsaturated alcohol has the following general formula R,R'-H
or CH3 n = 1 to 6, for example, ethylene glycol monoacrylate and monomethacrylate, propylene glycol monoacrylate and monomethacrylate, β-hydroxyethyl monoacrylate and monomethacrylate, β-hydroxypropyl monoacrylate and monomethacrylate, which can be used alone or in combination. Examples of α,β-unsaturated carboxylic acids include acrylic acid, methacrylic acid, and crotonic acid.

Examples include maleic acid, fumaric acid, and itaconic acid, which may be used alone or in combination. Monomers copolymerizable with the above two components are, for example, aromatic vinyl compounds such as styrene, α-methylstyrene, vinyltoluene, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, Alkyl esters of acrylic acid or methacrylic acid such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, vinyl acetate, vinyl ethyl ether, etc. are used alone or in combination. As a water-soluble thermosetting acrylic paint, the above α, β-unsaturated alcohol 10 to 40
Weight% (hereinafter abbreviated as "%").

α, β-unsaturated carboxylic acid 3-10%, vinyl monomer 5
It is preferable to use a copolymer containing 0 to 80% of a copolymer made water-soluble by alkali neutralization as the main ingredient. If the amount of α,β-unsaturated alcohol is less than the above range, the curability and specularity after vapor deposition of a metal film etc. will deteriorate, and if it exceeds the above range, heat crack resistance and adhesion will decrease. Also, the amount of α, β-unsaturated carboxylic acid is
If it is below the above range, it will not become water soluble, and if it is above the above range, the adhesion after vapor deposition will decrease. Furthermore, the amount of vinyl monomer should be within the above range so that the hardness and flexibility of the base layer satisfies the adhesion and crack resistance of the deposited film, and when it is out of the above range, the adhesion and crack resistance will decrease. become. Therefore, it is preferable to prepare a copolymer by setting the amount of α, β-unsaturated alcohol, etc. within the above-mentioned range, and use the copolymer made water-soluble by alkali neutralization as the main ingredient. Examples of the alkali used for the alkali neutralization include dimethylamine, diethylamine, and triethylamine.

Monoethanolamine, triethanolamine and ammonia are used. In addition, the molecular weight (Mw) of the water-soluble copolymer
) is preferably between 15,000 and 25,000.

If it exceeds this range, it will be difficult to obtain the reflective mirror that is the object of this invention in terms of adhesion, heat resistance, and specularity.

The main ingredient (A), the curing agent (B), and the (C) component contain 30 to 30% of the component (A) on a solid content basis.
70%, (B) component is 30-70%.

(C) component is set to 0 to 35%. That is, (A
It is necessary that the amount of the base resin, which is the component (), falls within the above range, and the amount of the curing agent, which is the component (B), also needs to be set within the above range.

If the amount of the curing agent is less than the above range, the curing properties will be insufficient and the heat crank resistance will be reduced, and if it exceeds the above range, the adhesion of the deposited film will be reduced.

The amount of pigment, component (C), must be set within 35%; if it exceeds 35%, mirror and surface properties will deteriorate. Further, the particle size of this pigment is required to be 15 microns or less, and if it exceeds 15 microns, the specularity will deteriorate.

Extender pigments include precipitated barium sulfate, zinc white, and calcium carbonate.

As the bright metal used for the bright metal film, A1+Ag
+Cr, Ni, etc. However, from the viewpoint of reflectance, cost, ease of vapor deposition, etc., it is most practical to use the old one.

The oxide used for the oxide protective film is SiO+Si.
Examples include O□, TiO□+Al103, and the like. However, in terms of transparency, stability, and economy, it is most practical to use SiO□.

The reflecting mirror of the present invention is manufactured using the raw materials as described above, for example, in the following manner. That is, a metal base material is degreased and dried in advance, and a water-soluble thermosetting acrylic paint is applied thereto by a method such as a spray method, an electrostatic coating method, and a dipping method. In this case, it is preferable to set the coating film thickness to 5 to 15 μm. When the coating thickness is less than 5 μm, specularity becomes insufficient if the surface of the base material is rough. Moreover, if it exceeds 15 μm, gas may remain in the coating film depending on the degree of baking when the coating film is baked in a subsequent step, causing inconvenience (occurrence of clouding) in the next step of vapor deposition, and also being disadvantageous in terms of cost. Next, the water-soluble thermosetting acrylic paint film is baked to form a base layer. The baking is preferably performed at 180 to 200°C for 20 minutes or more. However, the present invention is not limited thereto, and it is preferable to set the baking conditions to a temperature as low as possible and for a short time as long as it is possible to eliminate any residual volatile matter in the coating film that adversely affects vapor deposition in the subsequent process. Then, a bright metal is deposited on this underlayer. Vapor deposition may be performed by a normal method. That is, a bright metal is evaporated by resistance heating or electron beam heating under a vacuum of lo-4 to 10' Torr to form a metal film on the underlayer. This film thickness is 30
It is preferable to set the number in the range of 0 to 1000 people. When the film thickness is less than 300 mm, the base layer becomes transparent and the reflectance becomes low. On the other hand, even if the number of participants exceeds 1,000, no further increase in effectiveness can be expected and it becomes uneconomical in terms of cost. Note that, if necessary, bombardment treatment may be performed immediately before vapor deposition in order to improve the adhesion between the base layer and the metal film. Next, an oxide is deposited on the metal film.

That is, the oxide is evaporated by electron beam heating under a vacuum of 10 -4 to 10' Torr to form a predetermined film.

This film thickness is preferably set in a range of 0.3 to 2 μm. If the film thickness is less than 0.3μ, the oxide protective film will have many pinholes, resulting in poor corrosion resistance. On the other hand, if it exceeds 2 μm, no further increase in effect can be expected, and the deposition takes time and is uneconomical. In addition, when forming this oxide protective film,
If necessary, bombardment treatment may be performed before vapor deposition of the oxide to improve the adhesion between the oxide protective film and the metal film.

A reflecting mirror is manufactured in this way. The configuration of this reflecting mirror is shown in FIG. In the figure, ■ is a metal base material, 2 is a base layer, 3 is a metal film, and 4 is an oxide protective coating. This reflective mirror has excellent heat resistance, corrosion resistance, and specularity, so
It is particularly suitable as a reflector for HID light source lighting equipment such as outdoor sports lighting, factory lighting, road lighting, square lighting, etc.

Since this invention manufactures a reflecting mirror in the manner described above, the conventional separate cloth polishing and electrolytic polishing are no longer necessary, thereby avoiding an increase in cost and making it possible to obtain a reflecting mirror with excellent performance. Become. Moreover, since the present invention uses a water-soluble paint for the base layer, it does not require a huge amount of cost for pollution control.

Next, examples will be described together with comparative examples.

[Example 1] The solid content of the main ingredient is a water-soluble resin made by water-solubilizing a copolymer consisting of 12% β-hydroxyl acrylate, 5% methacrylic acid, 65% methyl methacrylate, and 18% styrene using triethylamine. 15% on a solid basis, a curing agent consisting of water-soluble methyl etherified henzoguanamine resin, 15% on a solid basis, and 10% titanium oxide, (water)/(ethylene glycol motuptyl ether) -3
A water-soluble acrylic paint was prepared by mixing it with 60% i agent of /l. Apply this paint to a degreased and dried aluminum base (15
cm x 15 cm x 1 mm) was spray coated to a film thickness of 10μ and baked at 180°C for 40 minutes to form a base layer. The aluminum plate coated with this base layer was set in a vapor deposition apparatus, and high purity aluminum (99,99%) was vapor-deposited by resistance heating in a vacuum of 5 x 10' Torr.
0 aluminum films were formed. Next, increase the vacuum level to 5X
While maintaining the pressure at 10-5 Torr, quartz (SiO□) was deposited by electron beam heating to form 5500 5i02 films. The reflector thus obtained had excellent specularity with a total reflectance of 87% and a diffuse reflectance of 2.0%, and was heated at 200'C.
No changes such as discoloration or clutter were observed even after being left in an atmosphere for 48 hours. Also, JIS H-8617
Salt spray test based on 1o cycle (1 cycle = 8■
No particular change was observed even after r spray + 16 + Ir pause). Humidity test (10"c ~ +60'c, 90~9
8%RH.

There was almost no change after 10 days). Adhesion (tape peel test) was also good both at the initial stage and after each of the above tests.

[Example 2] A water-soluble resin was prepared in the same manner as in Example 1 except that the same amount of butyl methacrylate was used in place of methyl methacrylate, and this was degreased and dried in the same manner as in Example 1. A base layer was formed on an aluminum base material, and an aluminum film with a thickness of 100 mm and a 5i02 film with a thickness of 5000 mm were formed thereon to obtain a reflecting mirror. This reflecting mirror has a total reflection rate of 89%.
Diffuse reflectance 1.5%, heat resistance test (200"c x 481
1r); No abnormality, salt spray test (10 cycles)
; Almost no change, humidity test (-10℃~+60℃,
(90-98% RI+, 10 days); almost no change; adhesion; excellent with no abnormalities at initial stage or after each test.

[Example 3] The hardening agent of the paint used in Example 2 was changed to a 1:1 mixture of water-soluble methyl etherified melamine resin and water-soluble methyl etherified benzoguanamine resin at 15% based on solid content. Using this, a reflecting mirror was obtained in the same manner as in Example 1. This reflector has a total reflectance of 87%, a diffuse reflectance of 1.9%, and has been tested for heat resistance.

No abnormalities were observed in either the salt spray test or the humidity resistance test. Adhesion was also good.

[Example 4] A parabolic shaped aluminum base molded product with a diameter of 580 m and a depth of 300 m was degreased and dried, and barium sulfate was used instead of titanium oxide in the paint of Example 2, and the amount was 10
%, paint with 50% solvent was applied and baked to create a base layer, and 900 people applied the old paint to this.

A reflecting mirror was obtained by depositing 5000 5i02. This reflecting mirror had a total reflectance of 87% and a diffuse reflectance of 3.6%, with almost no abnormalities observed in both the heat resistance test and the salt spray test 1 moisture resistance test. Adhesion was also good.

[Comparative example]

A base layer was formed on the aluminum base material using the same water-soluble thermosetting paint as in Example 2, and 8! 100 people were deposited. As a protective film, a silicone paint mainly composed of polydimethyl silicone was applied to a thickness of 5μ and heated to 40℃ at 180℃.
I baked it separately. The reflector thus obtained has a total reflectance of 85% and a diffuse reflectance of 5%.

After the heat resistance test (200°C x 48 hours), the surface became cloudy and the specularity decreased. After the salt spray test and the moisture resistance test, spotty corrosion occurred on the deposited film. However, the adhesion was good.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the present invention. 1... Metal base material 2... Base layer 3... Metal film
4... Oxide protective coating agent Patent attorney Takehiko Matsumoto Figure 1

Claims (1)

[Claims] (1) 30 to 70% by weight of the following component (A) on a solid content basis and 30 to 70% of the following component (B) on a solid content basis on the surface of the base material.
A base layer is formed using a water-soluble thermosetting acrylic paint containing 0% by weight and 0 to 35% by weight of component (C), and a glittering metal film is formed on this base layer by vapor deposition. 1. A method for manufacturing a reflecting mirror, characterized in that the reflecting mirror is obtained by forming a protective oxide film on a transparent metal film by vapor deposition. (A) A main component consisting of a water-soluble resin obtained by water-solubilizing a copolymer of an α,β-unsaturated alcohol, an α,β-unsaturated carboxylic acid, and a vinyl monomer copolymerizable with these by alkali neutralization. (B) Alkyl etherified melamine resin. A curing agent comprising at least one water-soluble alkyl etherified amino resin selected from the group consisting of an alkyl etherified urea resin and an alkyl etherified henzoguanamine resin. (C) At least one of an extender pigment and titanium oxide with a particle size of 15 μm or less. f21 The main ingredient (A) is 10 to 40% by weight of α,β-unsaturated alcohol, 3 to 10% by weight of α,β-unsaturated carboxylic acid, and 50 to 80% of vinyl monomer copolymerizable with these. Claim 1 consisting of a water-soluble resin obtained by making a copolymer of % by weight water-soluble by alkali neutralization.
Manufacturing method of the reflecting mirror described in Section 1.