JPS61235802A - Mirror coated plastic lens - Google Patents

Abstract

PURPOSE:To enhance strength of coat films and their adhesion to a base by forming a mirror coat layer of multilayer structure comprising a layer made of metal oxide or metal on a specified org. hard coat film formed on the surface of a lens. CONSTITUTION:The mirror coat layer of multilayer structure comprising a layer made of metal oxide and a layer made of metal or metal oxide are formed on the org. hard coat of a silicone type represented by formula (1) or (2) (R1 is 1-4C alkyl and R2, R3 are each 1-4C alkyl) or acrylic type, epoxy type, or melamine type formed on the surface of the plastic lens. The second SiO2 layer has an optical film thickness of lambda/4, lambda being 450-550nm, the third layer is made of Cr or Cr lower oxide, the fourth ZrO2 layer has an optical film thickness of lambda/4, the fifth layer is made of Cr or its lower oxide, the sixth SiO2 layer has an optical film thickness of lambda/4, and the seventh SiO layer has an optical film thickness of lambda/4, thus permitting the obtained coating films to have high mechanical strength, and low reflectivity and the obtained mirror coat film to have good reproducibility and strong adhesion to the plastic base.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a plastic mirror-coated lens that is resistant to scratches and reduces reflection on the surface side.

[Prior Art] Various types of sunglasses for leisure use are on the market, but recently, especially overseas, there has been an increase in the number of sunglasses whose glass surfaces are coated with a mirror coating to give them a metallic luster. However, since the base material of these mirror-coated sunglasses is glass, they are heavy and break easily, so they are often unsuitable for active leisure activities. In order to solve these problems, it is possible to make the base material organic.
Some mirror-coated lenses made of organic base materials are also commercially available. However, such mirror-coated lenses still have problems in terms of heat resistance of the material, and also have insufficient adhesion to metals, resulting in extremely poor scratch resistance of the lenses.

However, with recent advances in vacuum deposition methods, methods for improving the adhesion of metals to plastic materials have gradually been put into practical use. An example of applying these technologies to plastic mirror-coated sunglasses is JP-A-55-4671.
Publication No. 3, JP-A-55-46714, JP-A-55
It is disclosed in Japanese Patent Laid-open No. 46715-46715 and Japanese Patent Application Laid-Open No. 55-46716. These publications describe Cu%Au%M%Ti%N1, C, which are metals that can be used as mirror coats.
Various types of plastics are coated with r%CC01A and the like using high frequency ion derating to improve their adhesion.

[Problem that the invention seeks to solve]

However, for the actual use of eyeglass lenses and sunglasses, improving the adhesion of the coating film alone is not enough; especially in the case of plastic lenses, it is important to have sufficient scratch resistance on the surface. This has become a major issue. Furthermore, if a plastic lens is simply coated with metal, the reflection on both surfaces of the coating film will be strong, which will be disadvantageous in use as a mirror coated lens, and will reduce its commercial value.

[Means for solving problems]

In order to solve the above-mentioned problems of the conventional technology, the present inventors conducted a study, and as a result, applied an organic hard coat film with good scratch resistance as a base layer to the surface of plastic, and Focusing on the method of applying a mirror coat to the surface, an organic hard coat film made of silicone, acrylic, epoxy, melamine, etc. is applied as a base layer, giving flexibility, heat resistance, and weather resistance to this organic hard coat film. It has been found that if a mirror coat is then applied, the surface hardness of the mirror coat film can be kept high. It has also been found that by forming the mirror coat film into a multilayer film including a layer made of a metal oxide and a layer made of a metal or metal oxide, it is possible to reduce the reflection on the opposite surface while increasing the reflection on the coated surface.

The present invention was made based on such knowledge, and
An organic hard coat made of silicone, acrylic, epoxy, melamine, etc. is applied to the surface of a plastic lens, and a layer made of metal oxide and a layer made of metal or metal oxide are formed on the surface of the organic hard coat film. This is a plastic mirror-coated lens that is characterized by a multi-layered mirror coating.

In the present invention, the base layer provided on the surface of the plastic lens is silicone-based, acrylic-based, 2-epoxy-based,
This is an organic hard coat film made of melamine or other materials that has excellent flexibility, heat resistance, and weather resistance. In addition to diethylene glycol bisallyl carbonate polymer (CR-39), there are also materials that are difficult to dye, such as polystyrene and polycarbonate, for the substrate (plastic lens) on which the organic node coating film is provided. In this case, a silicone-based organic hard coat film is effective from the viewpoint of film hardness and dyeability. In addition, acrylics are preferred in terms of quick curing time for the organic hard coat film, and epoxy and melamine are more preferred in terms of film hardness.

As a silicone-based organic hard coat film, the general formula (
1) and general formula (2) [where R1 is an alkyl group having 1 to 4 carbon atoms, R2, R3
is an organic group selected from an alkyl group having 1 to 4 carbon atoms, -CH=CH2. ] A hydrolyzed wire mesh of one or two alkoxysilanes of Group A represented by, or one or two alkoxysilanes of Group A and an alkoxysilane represented by the general formula (3) % formula % (3) Alternatively, a coating obtained by applying and curing a coating liquid mainly composed of a hydrolyzed metal mesh with colloidal silica is particularly effective.

Here, the alkoxysilanes of Group A include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxyzolobyltrimethoxysilane, γ-glycyVxypropyltriethoxysilane , γ-glycidoxyzolobylmethyldimethoxysilane, γ-methacryloxyzolopyltrimethoxysilane, r-methacryloxypropylmethyltrimethoxysilane, dimethyldimethoxysilane, dimethyldimethoxysilane, phenyltriethoxysilane, cyclohexyltrimethoxysilane, Examples include γ-aminozologyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, r-chlorozolopyltrimethoxysilane, and r-mercaptopropyltriethoxysilane.

Examples of the alkoxysilane represented by the general formula (3) include tetramethoxysilane and tetraethoxysilane. The colloidal silica preferably has a particle size of about 5 mμ to 30 mμ when dispersed in water or alcohol. Hydrochloric acid and acetic acid are preferred as acids for hydrolyzing these alkoxysilanes or colloidal silicas. Although imidazole derivatives and the like are available as curing agents used in alkoxysilane or colloidal silica coating solutions, acetylacetone metal salts are particularly effective. The amount added is sufficient to harden the colloidal silica and the hydrolyzate of the organosilicon compound, for example, 1 to 1 g per 1 mole of the total of colloidal silica (5in2 equivalent) and the hydrolyzate of the organosilicon compound. be.

Examples of the solvent used in the coating liquid include lower alcohols, esters, ethers, and ketones, and particularly preferred are inpropyl alcohol citanol, methyl cellosolve, and the like.

A silicone surfactant can also be added to the coating liquid for the purpose of improving the smoothness of the coating film. Furthermore, it is also possible to add ultraviolet absorbers, antioxidants, etc. for the purpose of improving weather resistance or preventing deterioration of the coating film.

Furthermore, various additives can be added for the purpose of improving practicality such as improving adhesion with the substrate (plastic lens) and physical properties.

Furthermore, the addition of sodium acetate, which is generally used to stabilize the coating liquid or as a catalyst, is not preferred. The reason for this is that sodium acetate tends to precipitate toward the film surface after the coating composition is applied and cured, which has a negative effect on the film formation of vapor-deposited substances. This is because even if it is left in place, it will cause the same adverse effects as precipitation due to vacuum or heating.

The composition obtained above is then applied onto a plastic lens by a commonly used method such as the dipping method (dippinog method), the sugino coater method, the roll coater method, or the spray method.

The composition applied to the plastic lens is cured mainly by heat treatment, and the heating temperature can be varied over a wide range, but is preferably 40°C.
-150°C1 Particularly preferably 80°C - 120°C. A heating time of 1 to 4 hours or more gives good results.

The organic hard coat film obtained by heat curing treatment is
It has excellent wear resistance (hardness), flexibility (flexibility), heat resistance, and chemical (alkali) resistance.

Before applying the coating liquid, the plastic lens is preferably pretreated by an alkali treatment, a plasma treatment, an ultraviolet irradiation treatment, or the like.

The base material on which the organic hard coat film as described above is applied is diethylene glycol bisallyl carbonate polymer (C
R-39), polymethyl methacrylate (PMMA)
, polycarbonate, polystyrene, and the like. By providing such a plastic lens with the above-mentioned organic hard coat film, the surface hardness of the plastic lens can be increased without impairing its optical properties.

The mirror coat film provided on the base layer has a multilayer structure including a layer made of metal oxide and a layer made of metal or metal oxide. Here, the metal oxide is silicon monoxide (Si
O), silicon dioxide (8102), titanium dioxide ('ri
o2), zirconium dioxide (ZrO2), titanium trioxide (Ti2O3), -titanium oxide (TiO), Cr
Examples of metals include lower oxides of Cr.
Alternatively, Ti can be mentioned. As a result of examining various metal oxides and metals that can more fully maintain the adhesion and scratch resistance of the mirror coat film, we found that when forming the mirror coat film by vacuum evaporation, 5iO1S102, ZrO2, Ti
A combination of O2 metal oxide and Or or T1 metal is effective.

In addition, in the present invention, a multilayer structure including a base layer is used. , it is preferable to have seven two-coat layers.

In this case, if the base layer is the first layer, the second layer is 5iO1T
102 or ZrO2, the third layer is a thin film made of Cr or Ti metal, or a lower oxide of these metals, and the fourth layer is TiO2.
2. A thin film made of one or more metal oxides of ZrO2 or Ti2O3; the fifth layer is made of the same metal or metal oxide as the third layer, and has a thickness approximately twice that of the third layer; The 6th layer is a thin film made of SiO2, and the 7th layer is made of Sin%T.
By sequentially laminating each thin film layer of metal oxide of ie2, ZrO2, 'ri2o3, or TiO with a thickness of 1 m or more, a plastic mirror coated lens having such a multilayer mirror coat layer can be used as an eyeglass lens. As the fourth layer, especially Z
rO2λ/4, Cr or its lower oxide is particularly effective for the fifth layer, SiO2λ/4 is particularly effective for the sixth layer, and S10λ/4 is particularly effective for the seventh layer. At this time, the Cr film thickness is controlled by the transmittance and is 60% to 10%.
It is best to arbitrarily change the mirror strength between 1 and 2 to find the optimum conditions for mirror strength and anti-reflection. Further, it is desirable to provide a film that serves as an antireflection film on the surface of the plastic lens opposite to the surface on which the mirror coat film is provided. As such an antireflection film, SiO, Aj! 203, 5i02, ZrO
2, T10. There is a multilayer film formed by a vacuum evaporation method or the like.

Note that since the mirror coated lens of the present invention is made of plastic, it can be dyed according to preference before coating in order to adjust the transmitted color of the lens.

〔Effect of the invention〕

According to the present invention, it is possible to manufacture a plastic mirror-coated lens that has a high coating mechanical strength, has a mirror coat film with low reflection and good reproducibility on the dish surface, and has high adhesion to a plastic base material. I can do it.

[Embodiments of the invention]

Examples of the present invention will be described below based on the drawings, but the present invention is not limited thereto.

In addition, [parts] in the examples are parts by weight.

Example 1 Colloidal silica (Snowtex-40, Nikki Kagaku)
90 parts, 81.6 parts of methyltrimethoxysilane, 176 parts of γ-glycyVxyzolobylmethyldimethoxysilane,
A solution containing 2.0 parts of 0.5N hydrochloric acid, 20 parts of acetic acid, and 90 parts of water was stirred at room temperature for 8 hours and left at room temperature for 16 hours.

To this hydrolyzed solution, 120 parts of isopropyl alcohol,
120 parts of n-butyl alcohol, 16 parts of acetylacetone, 0.2 parts of a silicone surfactant, and 0.1 part of an ultraviolet absorber were added, stirred for 8 hours, and then aged at room temperature for 24 hours to obtain a coating liquid. .

This coating liquid was applied to a plastic lens (CR-39) 1 shown in FIG. 1 and cured by heating to provide an organic hard coat film 2. The thickness of this organic hard coat film 2 was about 3 μm. Next, 5iO (λ/4, λ: 45o~550
nm) layer 3, Cr(λ) layer 4 with a film thickness of 60% in transmittance
, zro2 (λ/4) layer 5, Cr(λ) layer 6.3i02 (λ/4) layer 7 with a film thickness of 20% in transmittance, Si
A multilayer film was formed by sequentially laminating O(λ/4) layers 8.

The surface of the mirror coat film formed as described above and 1
Characteristic diagrams of the spectral reflectance of the surface are shown in FIGS. 2(a) and 2(b), respectively. In FIG. 2, A is the spectral reflectance after the hard coat film treatment, and B is the spectral reflectance after the mirror coat film treatment. From Figure 2, it can be seen that in the mirror coat film of this example, the reflection on the coated side of the work surface is sufficiently strong over the entire visible range, and despite this, the reflection of the coat film on the first side is around 0.7% ( It can be seen that the lens also has a sufficiently good anti-reflection function, with residual reflection excluding 4% of the reflection from one surface of the lens.

Example 2 236 parts of γ-glycidoxyzolobyltrimethoxysilane, 220 parts of γ-glycylVxyzolylmethyltrimethoxysilane, 2.0 parts of 0.5N hydrochloric acid, 20 parts of acetic acid, 10 parts of water
The solution to which 0 part was added was stirred at room temperature for 8 hours, and the same procedure as in Example 1 was carried out to form a mirror coat multilayer film.

Example 3 r-methacryloxypropyltrimethoxysilane 496
1 part, 2.0 parts of 0.5N hydrochloric acid, 20 parts of acetic acid, and 100 parts of water were stirred at room temperature for 8 hours, and the same procedure as in Example 1 was followed to obtain a mirror coat multilayer film.

Example 4 r-methacryloxypropyltrimethoxysilane 248
Example 1: A solution containing 150 parts of colloidal silica (Snowtex-40, Nichiwa Kagaku), 2.0 parts of 0.5N hydrochloric acid, 20 parts of acetic acid, and 10 parts of water was stirred at room temperature for 8 hours. A mirror coat multilayer film was obtained in the same manner as above.

Example 5 100 parts of pentaerythritol tetraacrylate, 80 parts of trimethylolpropane triacrylate, 20 parts of ethylene glycol diacrylate, and 2.0 parts of benzoylethyl ether were added to obtain an acrylic coating composition that was polymerized by ultraviolet light.

This composition was applied to a CR-39 lens, polymerized and cured by ultraviolet irradiation, and a mirror coat film was applied thereon in the same manner as in Example 1 to obtain a multilayer film.

Comparative Example 1 A mirror film was directly deposited on top of the CR-39 lens by vapor deposition in the same manner as in the example, without providing an organic hard coat film.

The outline of various test methods will be explained below.

(a) Abrasion resistance = Added load 5 to the surface with #0000 steel cool
After rubbing with 00I 1000 times (back and forth), the following judgment was made.

A: It hardly gets scratched.

B: Slight damage.

C: Many scratches occur.

D=Peeling of the film occurs.

(Shun Adhesion 1) 10 x 10 pieces of Ryuhaku bibun were made, and a peel test using cellophane adhesive tape was performed 6 times to determine the number of remaining babun.

The cellophane Teso used was Nichiban JIS-Z-1522.

(C) Appearance Transparency, coloring state, surface state, etc. were examined by visual inspection.

(d) Solvent resistance The mirror sheet multilayer film was immersed in the following solution for 1 hour at room temperature to examine changes in the multilayer film.

Table 1 shows the test results for 1.7 ton solution 2, ethanol solution 6, toluene solution Examples 1 to 5 and comparative example 1.
Shown below.

As is clear from Table 1, it can be seen that the wear resistance of each of the Examples in which the organic hard coat film was applied was improved compared to the Comparative Example. Note that the organic hard coat films of Examples 1 and 2 can be dyed, and therefore, the use of such organic hard coat films is effective for plastic lenses such as polystyrene and polycarbonate that are difficult to dye.

Furthermore, the acrylic bar 2 coat film of Example 5 is cured by ultraviolet rays, so it has the advantage of being able to quickly form a highly hard film.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a partially enlarged sectional view of the machined surface of a lens showing an example of the present invention, and Fig. 2(a) is a partially enlarged sectional view of the machined surface of the mirror coated lens obtained in Example 1. Figure 2 is a reflectance characteristic diagram of the dish surface side of the mirror coated lens obtained in Example 1.

Claims (4)

[Claims] (1) An organic hard coat film made of silicone, acrylic, epoxy, melamine, etc. is applied to the surface of a plastic lens, and a layer made of metal oxide and a layer made of metal or metal oxide are placed on this organic hard coat film. A plastic mirror coat lens characterized by being coated with a multilayer mirror coat film comprising: (2) The silicone-based organic hard coat film has general formulas (1) and (2) “R_2-Si-(OR)_3...(1)”
▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・(2)
” Group A [where R_1 is an alkyl group having 1 to 4 carbon atoms, R_2,
R_3 is an alkyl group having 1 to 4 carbon atoms, -CH=CH_2
, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas, chemical formulas,
There are tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼, -CH_2CH_
2CH_2SH, -CH_2CH_2CH_2Cl, ▲
There are mathematical formulas, chemical formulas, tables, etc. ▼, -CH_2CH_2
CH_2NH_2, -CH_2CH_2CH_2NHC
It is an organic group selected from H_2CH_2NH_2. ] A hydrolyzed condensate of one or two alkoxysilanes from Group A, or one or two alkoxysilanes from Group A and general formula (3) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・...(3) [However, R_1 is an alkyl group having 1 to 4 carbon atoms]
The plastic mirror-coated lens according to claim 1, which is obtained by applying and curing a coating liquid whose main component is a hydrolyzed condensate with an alkoxysilane or colloidal silica represented by: (3) The mirror coat film consists of a second layer of SiO, a third layer of Cr, a fourth layer of ZrO_2, a fifth layer of Cr, a sixth layer of SiO_2, and a sixth layer of SiO_2 on the organic hard coat film (first layer). The plastic mirror coated lens according to claim 1, which is formed by sequentially laminating the seventh layer of. (4) The second layer of SiO has an optical thickness of λ/4 (λ: 450
~500nm), the third layer of Cr has a transmittance (λ) of 60~
50% film thickness, the fourth layer of ZrO_2 has an optical thickness λ/
4. The fifth layer of Cr has a transmittance (λ) of 20 to 10% thickness, the sixth layer of SiO_2 has an optical thickness of λ/4, and the seventh layer of SiO has an optical thickness of λ/4. Claim 3 which is 4
Plastic mirror coated lenses as described in section.