JPS5911665B2 - Manufacturing method for lighting reflector with excellent heat resistance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for manufacturing a reflecting mirror for lighting, and more particularly, a metal plating layer is formed on a metal surface, particularly a chromate-treated metal surface, by a vacuum evaporation method, thereby producing a thin film with a metallic luster. The present invention relates to a method of manufacturing a lighting reflector having excellent heat resistance.

It is well known that metal plating has been conventionally performed on metal surfaces by vacuum deposition using metals such as aluminum, copper, 15 chromium, nickel, etc., or alloys thereof.

The thickness of the metal plated body produced by this vacuum evaporation method is much thinner than 1 micron, so if the metal plated layer is formed directly on the bare surface of the metal adherend, the appearance will be significantly affected due to scratches on the bare surface, lack of smoothness, etc. Furthermore, there were drawbacks such as detachment of the metal plating layer due to extremely poor adhesion between the bare surface of the adherend and the metal plating layer.

In order to compensate for these defects, a resin film with a thickness of about 30 to 50 microns is interposed as a base coat layer between the bare surface of the adherend and the metal plating layer, and a metal plating layer is formed on the surface of the resin film. This is commonly done. The base coat layer is spray-coated with a resin solution prepared by dissolving melamine-alkyt resin, melamine-acrylic resin, acrylic resin, etc. in an organic solvent,
A method is used in which the material is solidified by heat treatment at 0° C. for about 30 minutes. However, this method requires heat treatment at high temperature for a long time, which requires a huge amount of thermal energy and has problems in terms of production efficiency.Also, because it contains a large amount of organic solvent, it is difficult to obtain a thick film. This resulted in poor finished appearance of the metal plated body and also caused problems in terms of resource conservation.

In recent years, in order to solve the above-mentioned problems, many attempts have been made to apply a resin liquid having an unsaturated group as a base coat layer and to treat it quickly and efficiently using active energy of ionizing radiation or electromagnetic waves. However, due to various problems, most of them have not reached the practical stage. In other words, one of the problems is to take an automobile's headlamp reflector as an example.The reflecting surface is made of an aluminum layer made by vacuum evaporation, but during the installation process to the automobile body, one end of the electric circuit cord is attached to the back of the reflector. It is necessary to solder or seal with waterproof adhesive, but the heat will cause a multicolored rainbow pattern or wrinkles on the surface of the aluminum plating layer that hits the reflective surface.
The biggest drawback was that the aluminum plating lost its original shine due to cracks and caused diffuse reflection, making it unable to function as a reflector for a headlamp. The present invention aims to solve these problems, bring the use of ultraviolet energy to a practical stage, and provide a method for efficiently manufacturing a lighting reflector with excellent heat resistance in a short time. (a) A resin liquid whose basic components are (1) a polymerizable polymer and/or a polymerizable oligomer and a polymerizable monomer containing a phosphorous element in the molecule, or (4) a (b) applying a resin liquid whose basic component is a polymerizable polymer and/or a polymerizable oligomer having at least one phosphorous element, solidifying it by irradiating it with ultraviolet rays, and (b) obtaining the base coat layer; The present invention relates to a method for producing a lighting reflector with excellent heat resistance, which comprises the step of vacuum depositing on the surface of a base coat layer at a vacuum degree of 1 x 10-5 T0rr or more to obtain a metal plating layer.

The "resin liquid" used in the present invention has (1) a polymerizable polymer and/or a polymerizable oligomer and a polymerizable monomer containing a phosphorus element in its molecule as basic components, and if necessary, A composition formed by mixing other polymerizable monomers, organic solvents, other photosensitizers, etc., or (4) a polymerizable polymer having at least one phosphorus element in the molecule and/or
Or, it consists of a composition consisting of a polymerizable oligomer as a basic component and optionally mixed with a polymerizable monomer having a phosphorus element, other polymerizable monomers, an organic compound, other photosensitizers, etc. .

More specifically, the polymerizable polymer and/or
Or the oligomer is a polymer and/or oligomer having at least one unsaturated group in the molecule.

Examples include unsaturated polyester resins, unsaturated acrylic resins, polyester-modified acrylic resins, epoxy-modified acrylic resins, urethane-modified acrylic resins, alkyd-modified acrylic resins, unsaturated group-containing polyolefin resins, and drying oils. Examples of unsaturated polyester resins include Rigolak 2460uv (Showa Kobunshi) and Polylite CH.
-303 (Dainippon Ink), Diabeam K-8303 (Mitsubishi Rayon) as an unsaturated acrylic resin, Aronix M8O3 as a polyester-modified acrylic resin.
O, Aronix M8O6O (Toagosei Chemical Industry Co., Ltd.), etc. Also, as an epoxy modified acrylic resin, UcOat
2Ol (Toho Chemical Industry), Datecrite UE8lOO
, Deitzkulite UE82OO (Dainippon Ink & Chemicals), etc. As a urethane modified acrylic resin, XP-
1077-40-2 (Nippon Gosei), XP-51-3
7-70-2 (Nippon Gosei Kagaku), etc. Examples of alkyd-modified acrylic resins include XP-14-22 (Nippon Gosei Kagaku). Among the above polymers and/or oligomers, particularly preferred are polyester-modified acrylic resins and/or epoxy-modified acrylic resins. In addition, as the polymerizable monomer containing phosphorus element in the molecule,
For example, mono(2-hydroxyethyl acrylate) acid phosphate, mono(2-hydroxyethyl methacrylate) acid phosphate, mono(3-hydroxypropyl acrylate) acid phosphate, mono(3
-hydroxypropyl methacrylate) acid phosphate, di(2-hydroxyethyl acrylate) acid phosphate, di(2-hydroxyethyl methacrylate) acid phosphate, di(3-hydroxypropyl acrylate) acid phosphate, di(3-hydroxy Phosphoric acid esters of acrylic acid or methacrylic acid containing hydroxyl groups such as proyl methacrylate) acid phosphate, acrylic alcohol acid phosphate, vinyl phosphate, vinyl phosphonic acid, mono(2
-hydroxyethyl acrylate) acid phosphite, di(2-hydroxyethyl acrylate) acid phosphite, di(2-hydroxyethyl methacrylate)
acidophosphite, etc., and their salts and esters, or a mixture of two or more thereof, and particularly preferred are mono(2-hydroxyethyl acrylate) acid phosphate and mono(2-hydroxyethyl methacrylate) acid phosphate. , di(2-hydroxyethyl acrylate) acid phosphate and other phosphoric acid esters of acrylic acid or methacrylic acid containing a hydroxyl group. The polymerizable polymer or oligomer containing at least one phosphorus element in the molecule may be a polymer or oligomer obtained from a polymerizable monomer containing phosphorus element in the molecule, or an epoxy Alternatively, a polymer modified with polyester or the like may be used.

By using a resin liquid containing phosphorus in the present invention, the adhesion of a film obtained from the resin liquid to a metal material can be significantly improved.

Moreover, as a result, physical and chemical properties such as corrosion resistance can be improved. On the other hand, other polymerizable monomers used as optional components for these components are monomers having at least one unsaturated group in the molecule, such as (a) (meth)acryloyl group-containing monomers. body,
(b) An aromatic vinyl group-containing monomer or (c) an aliphatic vinyl group-containing monomer. Among the above (a), examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate. Examples of ether compounds of the above-mentioned hydroxyl group-containing monomer and alkyl alcohol or cyclic alkyl alcohol include methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, and tetrahydrofurfuryl acrylate. Furthermore, as an ester compound of (meth)acrylic acid and alkyl alcohol, (
Methyl acrylate, butyl (meth)acrylate,
Neopentyl glycol di(meth)acrylate, 1-
Examples include 6-hexanediol di(meth)acrylate and trimethylolpropane tri(meth)acrylate. Examples of the aromatic vinyl group-containing monomer (b) include styrene and vinyltoluene, and examples of the aliphatic vinyl group-containing monomer (c) include vinyl acetate and vinylidene chloride. Particularly preferred among the above polymerizable monomers are ether compounds of hydroxyl group-containing monomers and alkyl alcohols in group (a), and esters of hydroxyl group-containing monomers and (meth)acrylic acid and alkyl alcohols. It is a compound.

The "resin liquid" of the present invention includes a polymerizable polymer and/or oligomer and a polymerizable monomer having a phosphorus element in the molecule, or a polymerizable polymer and/or a polymerizable polymer containing at least one phosphorus element in the molecule. With oligomers as the basic ingredient,
Depending on the difficulty of the coating work, the surface condition of the coating film, etc., the viscosity and properties of the resin liquid are adjusted by appropriately combining the above-mentioned polymerizable monomers.

In particular, when a low viscosity resin liquid is required, an organic lubricant is also used. In the present invention, the resin liquid includes (1) a polymerizable polymer and/or a polymerizable oligomer (a);
When the basic component is a polymerizable monomer (b) containing a phosphorus element in the molecule, the ratio of both is (a)/(b)-99.
/1 to 70/30 (wt%), preferably 95/5 to 8
0/20 (wt%), and if necessary, other polymerizable monomers are added to the total amount of monomers in the entire composition of the resin liquid (the sum of the phosphorus element-containing polymerizable monomer and other polymerizable monomers). ) is 50 weight? It can be added within the following range.

In addition, when the resin liquid has (4) a polymerizable polymer and/or oligomer containing at least one phosphorus element in the molecule as a basic component, 5% of the total composition of the resin liquid may be added as necessary.
0 weight? The following phosphorus element-containing polymerizable monomers and/or other polymerizable monomers can be contained.

However, when a polymerizable monomer containing phosphorus element in the molecule is used, the monomer should be in the range of 1 to 30% by weight in the total resin liquid composition. The basic component (1) above, which has a large adhesion imparting effect, is more preferred.

However, in (1) above, if the amount of the polymerizable monomer containing phosphorus element in the molecule is less than 1% by weight, the effect of imparting adhesion to the metal surface will be small, and if it exceeds 30% by weight, the water resistance of the coating film will deteriorate. This is not preferable because it lowers the temperature. As mentioned above, the resin liquid for the base coat layer of the present invention uses an epoxy-modified acrylic resin and/or a polyester-modified acrylic resin as a polymerizable polymer and/or oligomer, and uses a polymerizable monomer containing a phosphorus element in its molecule. Things (2-
Hydroxyethyl acrylate) acid phosphate,
Mono(2-hydroxyethyl methacrylate) acid phosphate, di(2-hydroxyethyl acrylate)
A phosphoric acid ester monomer of (meth)acrylic acid containing a hydroxyl group such as acid phosphate or di(2-hydroxyethyl methacrylate) acid phosphate is used, and if necessary, a (meth) acryloyl group is added as another polymerizable monomer. Most preferred is a composition containing one type of polymerizable monomer or a mixture of two or more types thereof.

The polymerizable polymer and/or oligomer, the phosphorus element-containing polymerizable monomer, and the other polymerizable monomers are not limited to only one type, but may be used in an appropriate combination of two or more, and each It is also possible to show characteristics. Furthermore, since ultraviolet rays are used as an energy source for solidifying the resin liquid of the present invention, it is necessary to add a photosensitizer.

For example, photosensitizers include benzoin, benzoin methyl ether, benzoin isopropyl ether, benzyl, benzophenone, anthraquinone, naphthoquinone,
Examples include chloranthraquinone, tetramethylthiuram disulfide, diphenyl disulfide, 2,2-diethoxyacetophenone, benzoin peroxide, azobisisobutyronitrile, 2,2-azobispropane, etc. The amount used is 0.05 to 15 parts by weight, preferably 2 to 5 parts by weight, based on 100 parts by weight of the total amount of polymerizable polymer and/or oligomer and polymerizable monomer in the resin liquid. Other additives such as a leveling agent, a polymerization inhibitor, an anti-sagging agent, etc. can be added to the resin liquid of the present invention as necessary, and on the other hand, talc, calcium carbonate, magnesium carbonate, silica, barium sulfate, etc. Extender pigments such as
It is also possible to mix it with coloring pigments, antirust pigments, etc. and use it in the same form as known coating compositions.

In the method for producing a metal plated body of the present invention, first, a cutting resin liquid is applied to a metal surface by a known method such as a roll coater, spray, curtain flow coater, or brush coating to a desired film thickness, preferably about 30 to 50 microns. Apply and irradiate with ultraviolet rays after setting if necessary.

Next, a metal plating layer having a thickness of about 200 to 500 λ made of metals such as aluminum, chromium, nickel, copper, and alloys thereof may be formed on the surface of the solidified base coat layer by vacuum evaporation. As mentioned above, conventional metal plating bodies obtained by using known ionizing radiation or electromagnetic wave active energy irradiation and solidification as a base coat layer have poor heat resistance and have not been put to practical use. However, as a result of research into the causes of defects such as multicolored rainbow patterns, wrinkles, cracks, etc., the inventors have found that the cause is a trace amount of polymerizable monomer remaining in the base coat layer after solidification. Ivy.

As a method for removing the residual polymerizable monomer, an attempt was made to extend the ultraviolet irradiation time, but this had little effect. The present inventors filed an application for a method of removing residual polymerizable monomers by heat-treating a base coat layer in a pre-process to form a metal plating layer.

After that, as a result of various studies, we found that the same effect can be obtained by maintaining the degree of vacuum during vacuum evaporation at 1 x 10-5T0rr or higher, and then applying heat treatment by applying a metal plating layer using the vacuum evaporation method. We have arrived at the heading Invention.

Conventionally, the degree of vacuum in known vacuum evaporation plating is generally about 3 x 10-4 to 7 x 10-5T0rr, but at this level of vacuum, residual polymerizable monomers in the base coat layer are removed. Removal is completely ineffective.

It is presumed that by maintaining the base coat layer under a high degree of vacuum as in the present invention, there is an effect of suctioning and removing a small amount of the polymerizable monomer remaining in the base coat layer, and thus the surface of the base coat layer from which the remaining polymerizable monomer has been removed. A metal plating layer applied to the base coat layer is extremely effective in significantly improving the mutual adhesion between the base coat layer and the metal plating layer.

The metal-plated body thus obtained has extremely excellent heat resistance, with no multicolored rainbow patterns, wrinkles, cracks, etc. observed even when heated. Since the metal plating layer of the metal plating body obtained by the method of the present invention is an extremely thin film, for the purpose of protecting the plating layer and preventing surface contamination, a coat of the same type as that used for the base coat described above is applied to the surface of the metal plating layer. Apply a resin liquid of It is also possible to provide a surface protective layer by applying and solidifying a thermosetting resin liquid such as a liquid or a room temperature curing resin liquid such as a polyurethane resin liquid or an epoxy resin liquid.
Next, specific effects of the present invention will be explained by giving examples. "Part" or "?" means "part by weight" or "% by weight"
shows. Example 1 (1) UCOat2Ol [manufactured by Toho Chemical Industry Co., Ltd.] Each of the above resin liquids was spray-painted on the surface of a polished and cleaned cold-rolled steel sheet and a chromate-treated steel sheet to a dry film thickness of 50 microns, and the coating was applied for 10 minutes at room temperature. After setting, lamp input 8
Irradiation distance 20CT with one 0W/Cm high pressure mercury lamp
! A base coat layer was obtained by irradiating with L for 60 seconds.

Next, the surface of the base coat layer is coated with a vacuum degree of 1 using a vacuum evaporation method.
An aluminum plating layer of 500λ was formed under the conditions of x10-5T0rr to obtain a metal plating body. Example 2 The resin liquid was sprayed onto the surface of a polished and cleaned cold-rolled steel sheet and a chromate-treated steel sheet to a dry film thickness of 50 microns. After painting and setting in a hot air drying oven at 50℃ for 5 minutes,
A base coat layer was obtained by irradiating for 60 seconds at an irradiation distance of 20 crIL using one high-pressure mercury lamp with a lamp input of 80 W/Cm.

Next, the surface of the base coat layer is coated with a vacuum degree of 3 using a vacuum evaporation method.
An aluminum plating layer of 500λ was formed under the conditions of ×104T0rr to obtain a metal-plated body. Example 3 The resin liquid was spray-painted on the surface of a cold-rolled steel sheet and a chromate-treated steel sheet that had been polished and cleaned to a dry film thickness of 50 microns, and after setting at room temperature for 10 minutes, lamp input 1 was applied.
Irradiation distance 2 with one 60W/C77L high pressure mercury lamp
0? was irradiated for 30 seconds to obtain a base coat layer.

Next, an aluminum plating layer having a thickness of 500λ was formed on the surface of the base coat layer by vacuum evaporation at a vacuum degree of 5×10 4 T0rr to obtain a metal plating body. Example 4 Using the resin solution of Example 1, the surfaces of cold-rolled steel sheets and chromate-treated steel sheets that had been polished and cleaned were spray-painted to a dry film thickness of 30 microns, and after setting at room temperature for 10 minutes,
Lamp input 160W/? A base coat layer was obtained by irradiating with one high-pressure mercury lamp at an irradiation distance of 20 CTIL for 30 seconds.

Next, the surface of the base coat layer is coated with a vacuum degree of 1 using a vacuum evaporation method.
An aluminum plating layer was formed by 300 people under the conditions of x104T0rr to obtain a metal plating body. Comparative Example 1 A test specimen was obtained in the same manner as in Example 1 using a composition obtained by removing mono(2-hydroxyethyl acrylate) acid phosphate from the resin liquid of Example 1.

Comparative Example 2 A test specimen was obtained in the same manner as in Example 2 using a composition obtained by removing di(2-hydroxyethyl acrylate) acid phosphate from the resin liquid of Example 2.

Comparative Example 3 A test specimen was obtained in the same manner as in Example 3 using a composition obtained by removing mono(2-hydroxyethyl methacrylate) acid phosphate from the resin liquid of Example 3.

Comparative Example 4 Using the resin liquid of Comparative Example 1, a test specimen was obtained in the same manner as in Example 4.

Comparative Example 5 A base coat layer was obtained using a resin liquid having the same composition as in Comparative Example 1 and using the same procedure.

Next, the surface of the base coat layer is coated with a vacuum degree of 1 using a vacuum evaporation method.
A metal-plated body was obtained by forming 500 aluminum layers under the conditions of x10-4T0rr. Comparative Example 6 A base coat layer was obtained using a resin liquid having the same composition as in Comparative Example 2 and using the same procedure.

Next, the surface of the base coat layer is coated with a vacuum degree of 5 using a vacuum evaporation method.
A metal-plated body was obtained by forming 500 aluminum layers under the conditions of x10-5T0rr. Comparative Example 7 A base coat layer was obtained using a resin liquid having the same composition as in Comparative Example 3 and using the same procedure.

Next, an aluminum layer of 500 λ was formed on the surface of the base coat layer by vacuum evaporation at a vacuum degree of 7×10 −5 T0rr to obtain a metal-plated body. Table 1 shows the results of comparative evaluation of the effects using the metal plated bodies obtained in Examples 1 to 4 and Comparative Examples 1 to 7.

Claims (1)

[Claims] 1 (a) on the metal surface, (i) a polymerizable polymer and/or
Or a resin liquid whose basic components are a polymerizable oligomer and a polymerizable monomer containing a phosphorus element in the molecule, or (
ii) a step of applying a resin liquid whose basic component is a polymerizable polymer and/or a polymerizable oligomer having at least one phosphorus element in the molecule, and solidifying it by irradiating it with ultraviolet rays to obtain a base coat layer; (b) A method for producing a lighting reflector with excellent heat resistance, comprising the step of performing vacuum deposition on the surface of the base coat layer at a vacuum degree of 1×10^-^5 Torr or more to obtain a metal plating layer. 2 The resin liquid (i) contains 99% to 30% by weight of a polymer and/or oligomer of an epoxy-modified acrylic resin and/or a polyester-modified acrylic resin having at least one unsaturated group in the molecule; and 1% to 30% by weight of a polymerizable monomer containing at least one phosphorus element.
A method for producing a lighting reflector with excellent heat resistance as described in 2. 3. The method for manufacturing a lighting reflector with excellent heat resistance according to claim 1, wherein the metal plating layer is made of aluminum or an alloy thereof.