JPH07117602B2 - Method for manufacturing colored plastic lens - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a colored plastic lens.
The colored plastic lens obtained by the present invention is preferably used as an eyeglass lens.

[Prior Art] Plastic lenses are lighter in weight, more resistant to impact, less likely to break, and easier to process than glass lenses, and therefore the amount of plastic lenses used has been rapidly increasing in recent years. The material of the plastic lens is polymethylmethacrylate,
Polystyrene, cellulose propionate, polycarbonate, diethylene glycol bisallyl carbonate polymer (CR-39), etc. are available, and since these are excellent in dyeability and can be freely dyed, we supply fashionable lenses according to customer's taste. It has become possible, and the fashion of eyeglasses is becoming more sophisticated every year.

Under these influences, spectacle lens manufacturers are required to uniformly and mass-produce plastic lenses with various colors in a large amount. A conventional method for dyeing a plastic lens is to use a disperse dye, a basic dye or the like to immerse the plastic lens in a dyeing solution at a predetermined temperature and a predetermined dye concentration as disclosed in JP-A-58-5716. Is.

[Problems to be Solved by the Invention] However, the above-mentioned dyeing method of immersing the dyeing solution in the dyeing solution involves variations in dye concentration in the dyeing solution, amount of auxiliary agent, temperature of the dyeing solution and degree of aging, and dyeability of the plastic lens substrate. Therefore, it is difficult to color the plastic lens uniformly and in large quantities because the color tone is likely to change greatly.In addition, the plastic lens colored by this method requires color correction in order to obtain a uniform color. It also causes a big hindrance in work efficiency. As a method for solving this problem, for example, it is possible to control the above factors to be constant, but it is substantially difficult to control these factors, and it has not yet been possible to color the plastic lens uniformly in a large amount and stably. .

Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to provide a large amount and stably of uniformly colored colored plastic lenses.

[Means for Solving the Problem] The above object of the present invention is to provide a method for producing a colored plastic lens having a multi-layer antireflection film having at least one colored layer on a plastic lens substrate, wherein the colored layer is metallic chromium. And a silicon dioxide mixture by vapor deposition to form a chromium oxide layer.

That is, in the method for producing a colored plastic lens of the present invention, at least one layer of the multilayer antireflection film is a colored layer containing a metal or a metal oxide colorant, so that the antireflection film also has a function as a colored layer. It is based on a unique idea that has never existed before.

Hereinafter, the present invention will be described in detail.

Examples of the plastic lens substrate provided with the multilayer antireflection film in the present invention include conventionally known polymethyl methacrylate, polystyrene, cellulose propionate, polycarbonate, and diethylene glycol bisallyl carbonate polymer (CR-39).

These plastic lens substrates may be subjected to a surface treatment, and specific examples of the surface treatment include a surface made of an organic substance (for example, an organic silicon compound), an inorganic substance (for example, colloidal silica) or a mixture thereof on the plastic lens substrate. Forming a treated film can be mentioned.

On the plastic lens substrate or the surface-treated plastic lens substrate, further, in order to improve the adhesion between the substrate and the antireflection film and to increase the hardness of the plastic lens surface, silicon monoxide or silicon dioxide is used. Alternatively, an inorganic cured film made of a mixture of these may be formed to have an optical film thickness of λ to 5λ depending on the surface condition of the plastic lens substrate.

The method for producing a colored plastic lens of the present invention comprises the above-mentioned plastic lens substrate (as described above, if necessary, the plastic lens substrate is subjected to surface treatment, and the plastic lens substrate or the surface-treated plastic lens substrate is subjected to monoxide treatment). A multilayer antireflection film may be formed by vapor deposition on an inorganic cured film formed of silicon, silicon dioxide, or a mixture thereof, and at least one layer of the multilayer antireflection film is used as a chromium oxide-based coloring layer. The chromium-based colored layer is formed by subjecting a mixture of metallic chromium and silicon dioxide to vapor deposition.

The multilayer antireflection film is a two-layer equivalent film (refractive index of about 1.65) consisting of a high-refractive index material layer (preferred optical film thickness 0.04λ) and a low-refractive index material layer (0.08λ of the same). A high refractive index layer (same λ / 4), a colored layer and a high refractive index layer (same λ / 4), and a low refractive index layer (same λ / 4) made of a low refractive index material in this order It is preferably formed on the substrate directly or through the surface-treated film and / or the inorganic cured film.

As the high-refractive index material forming each layer of the antireflection film, one or more selected from titanium oxide, cerium oxide, zirconium oxide, indium oxide, neodymium oxide, tantalum oxide and silicon monoxide is used. To be As the low refractive index substance, one or two selected from magnesium fluoride and silicon dioxide are used.

The chromium oxide-based colored layer forming a part of the multilayer antireflection film having the above-mentioned structure is formed by subjecting a mixture of metallic chromium and silicon dioxide to vapor deposition. That is, when a mixture of metallic chromium and silicon dioxide is heated to a temperature of less than about 1500 ° C. for vapor deposition, the silicon dioxide decomposes to produce non-evaporable metallic silicon and oxygen, which oxygen and metallic chromium. Only the chromium oxide produced by the reaction is deposited. Since this chromium oxide is a brown or brown high refractive index substance, it serves as both the colored layer and the high refractive index layer.

On the other hand, when silicon monoxide structurally closely related to silicon dioxide is used together with metallic chromium instead of silicon dioxide,
Unlike silicon dioxide, silicon monoxide is vapor-deposited below the temperature at which metallic chromium or chromium oxide is vapor-deposited, and the obtained silicon monoxide vapor-deposited layer has a unique color that is unsuitable as a coloring layer. The use of silicon should be avoided.

The multilayer antireflection film may have the following layer structure.

That is, an inorganic cured film made of silicon monoxide, silicon dioxide, or a mixture thereof is formed on a plastic lens substrate having an optical film thickness of λ to 5λ depending on the state of surface treatment. / 6 high refractive index material layer, optical thickness λ / 3 low refractive index material layer, optical thickness λ / 4 colored layer and high refractive index layer 3 layers in this order Is 1.65
This is a multilayer antireflection film obtained by forming an equivalent film layer to a certain degree and then forming a low refractive index substance layer having an optical film thickness of λ / 4.

In the specific examples of the above two antireflection films, the high refractive index layer contains a metal or metal oxide-based coloring substance to serve also as the coloring layer, but the low refractive index layer contains the above coloring substance. ,
You may make it serve also as a coloring layer.

[Operation] It is widely practiced to provide a multilayer antireflection film on a plastic lens substrate, but the method for producing a colored plastic lens of the present invention is not limited to the multilayer antireflection film provided on the plastic lens substrate. At least one layer is formed by a colored layer containing a metal or a metal oxide-based coloring substance, and the antireflection film functions as a colored layer in addition to the original antireflection function.

Also, since the colored layer is formed by vapor deposition,
As compared with the case where a colored plastic lens is obtained by immersing in a dyeing solution, there is no unevenness in color, variation in color tone, etc., and the uniformity of coloring is secured.

[Examples] Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited to the examples.

Plastic lens (Hoya Co., Ltd. Hi-Lux lens,
A coating solution containing alkoxysilane as an organosilicon compound is applied to the surface of the material diethylene glycol bis-allyscarbonate polymer (CR-39), refractive index 1.499) and heated at 120 ° C for 2 hours to give a film thickness of 2-3μ. A surface treatment film was formed.

Next, the surface-treated plastic lens substrate obtained is placed in a vacuum chamber, and while the substrate surface is kept below 120 ° C, silicon dioxide is heated to a temperature above 1500 ° C and evaporated to form an inorganic cured film. Let

Next, a multilayer antireflection film was formed on the obtained plastic lens substrate having the inorganic cured film as follows.
That is, first, zirconium oxide is used as the high refractive index substance, and silicon dioxide is used as the low refractive index substance, and the former is first deposited, and then the latter is deposited. A two-layer equivalent film of 0.08λ (refractive index 1.65) was formed.

Next, zirconium oxide was used as the high-refractive index material, and this was evaporated to form a high-refractive index layer having an optical film thickness of λ / 4 on the two-layer equivalent film.

Next, a mixture of metallic chromium and silicon dioxide is used, and the mixture is heated to a temperature of less than about 1500 ° C., for example, 1000 to 1400 ° C. to perform a vapor deposition process, and the silicon dioxide decomposes to form non-evaporable metallic silicon. Oxygen is generated, and oxygen is generated by reacting with metallic chromium, and only brown or brown chromium oxide is vapor-deposited on the high refractive index layer to obtain an optical film thickness of λ / 4.
The colored layer and the high refractive index layer were formed.

Finally, use silicon dioxide as the low refractive index material
A low refractive index layer having an optical thickness of λ / 4 was formed on the colored layer / high refractive index layer by heating at a temperature of 1500 ° C. or higher and vapor deposition.

Since the antireflection film was formed by the vapor deposition method, a large amount of the antireflection film could be stably formed.

The spectral reflectance curve in the visible region of the colored plastic lens thus obtained is shown in FIG. 1, and the spectral transmittance curve in the visible region is shown in FIG. From FIG. 1, it is clear that the plastic lens of the present invention has a reflectance of 5% or less in the entire visible region and has an excellent antireflection function. From Fig. 2, the wavelength is about 60.
Since the transmittance gradually decreases from 0 nm toward the lower wavelength, it is clear that the colored layer is formed. Further, since the transmittance sharply decreases from a wavelength of about 400 nm toward a short wavelength, the colored plastic lens of the present invention,
It became clear that harmful ultraviolet rays can be cut.

The obtained colored lens of this example was visually inspected, but no color unevenness was observed.

[Advantages of the Invention] In the colored plastic lens obtained by the present invention, the multilayer antireflection film not only functions as an original antireflection function but also functions as a coloring layer, and the coloring layer is formed by vapor deposition. Unlike a plastic lens dyed with a dye, the uniformity of coloring is ensured.

In addition, since the colored layer is simultaneously formed in the process of forming the antireflection film by vapor deposition without providing a separate dyeing step with a dye, the method for producing a colored plastic lens of the present invention is excellent in mass productivity and can be produced stably. There is an advantage that you can.

[Brief description of drawings]

FIG. 1 is a spectral reflectance curve diagram of the colored plastic lens obtained in the example of the present invention, and FIG. 2 is a spectral transmittance curve diagram of the colored plastic lens.

Claims (1)

[Claims] 1. A method for producing a colored plastic lens having a multilayer antireflection film having at least one layer consisting of a colored layer on a plastic lens substrate, wherein the colored layer is vapor-deposited with a mixture of metallic chromium and silicon dioxide. A method for manufacturing a colored plastic lens, which is provided by forming a chromium oxide layer.