JP2013054275A - Dyed lens and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dyed lens excellent in short wavelength light absorption performance of 380 to 450nm, and a method of manufacturing the same.SOLUTION: A dyed lens is dyed using a compound represented by the general formula [I], where Rrepresents alkyl group or aralkyl group which may be branched, Rrepresents -CN or -COOR, Rrepresents alkyl group or aralkyl group which may have substituent group (excluding ethyl group in the case of Rbeing methyl group).

Description

  The present invention relates to a dyed lens and a manufacturing method thereof.

In recent years, plastic lenses are frequently used for spectacle lenses because of their advantages of being lightweight, excellent in impact resistance and easy to dye.
Ultraviolet rays are said to have various adverse effects on the human body, and there is an increasing demand for ultraviolet cut lenses for protecting eyes from ultraviolet rays in eyeglass lenses. As a method for imparting ultraviolet cut ability to a plastic lens, a method is disclosed in which a specific ultraviolet absorber is added to a plastic lens monomer and polymerized to form a plastic lens (see Patent Document 1).

Japanese Patent No. 4681820

Recent research has revealed that not only ultraviolet rays but also the blue region (380 nm to 500 nm) of visible light is cut to reduce glare and improve visibility and contrast.
In addition, it is said that the blue region of visible light has strong energy for the health of the eyes, causing damage to the retina, eye diseases, flickering of the visual field, and a decrease in contrast. Damage caused by blue light is called “blue light hazard”, and it is said that it is desirable to cut off the light in this region.

Furthermore, it is generally known that light energy is half proportional to the wavelength of light, and the scattered light energy of Rayleigh scattering is known to be half proportional to the fourth power of the wavelength. Therefore, it is considered that reducing the light energy received by the eyes by cutting light with a short wavelength of 380 to 450 nm is an effective measure for damage to the retina, eye diseases, flickering of the visual field, and contrast reduction.
However, the conventional dyeing lens does not yet have a cutting ability of 380 nm to 450 nm, and development of a dyeing lens that effectively cuts light in this region is desired.

  This invention is made | formed in view of the said situation, and aims at providing the dyeing | staining lens excellent in the short wavelength light absorption performance of 380 nm-450 nm, and its manufacturing method.

In order to solve the above problems, the dyed lens of the present invention comprises a compound represented by the following general formula [I] (wherein R ¹ is an alkyl group or aralkyl group which may be branched, R ² is —CN or -COOR ³ and R ³ are characterized by being dyed using an alkyl group or an aralkyl group which may have a substituent (excluding an ethyl group when R ¹ is a methyl group).

  In order to solve the above problems, a method for producing a dyed lens according to the present invention is a method for producing the dyed lens according to the present invention, wherein at least one surface of the plastic substrate is represented by the above general formula [I]. It is characterized by dyeing | staining using a compound.

  ADVANTAGE OF THE INVENTION According to this invention, the dyeing | staining lens excellent in the short wavelength light absorption performance of 380 nm-450 nm and its manufacturing method can be provided.

2 is a transmittance curve of the dyed lenses of Example 1 and Comparative Example 1. FIG. 6 is a transmittance curve of the dyed lens of Example 2. FIG. It is the transmittance | permeability curve of the dyeing lens of Examples 3-6 and the plastic lens of the comparative example 2. It is the transmittance | permeability curve of the dyeing | staining lens of Example 7 and Comparative Example 3. FIG. It is the transmittance | permeability curve of the dyeing | staining lens of Example 8 and Comparative Example 4. FIG.

Hereinafter, the dyeing lens of the present invention and the manufacturing method thereof will be described in detail.
In order to develop a dyed lens excellent in absorption performance in the short wavelength region (380 to 450 nm) of visible light, the present inventors use various compounds having the property of absorbing light in the short wavelength region of visible light. A method for dyeing a plastic substrate was examined. As a result, it has been found that a dyed lens having desired light transmittance characteristics cannot be obtained simply by dyeing using a compound having a light absorption ability in the short wavelength region. More specifically, as shown in Comparative Example 4 described later, when a plastic substrate is dyed with a dye having a light absorption ability in a short wavelength region, the obtained dyeing lens has a short wavelength light with a wavelength of 380 to 450 nm. However, there is also a problem that a dyed lens is easily colored and a lens having a desired color cannot be obtained. As a result of intensive studies, the present inventors provide a dyed lens that effectively cuts only short-wavelength light of 380 nm to 450 nm when a plastic substrate is dyed using a compound represented by the following general formula [I]. It has been found that it can be done, and has reached the present invention.

The dyed lens of the present invention comprises a compound represented by the following general formula [I] (wherein R ¹ is an alkyl group or an aralkyl group which may be branched, R ² is —CN or —COOR ³ , R ³ is It is characterized by being dyed using an alkyl group or an aralkyl group which may have a substituent (excluding an ethyl group when R ¹ is a methyl group).

In the above general formula [I], R ¹ includes an alkyl group having 1 to 12 carbon atoms or an aralkyl group which may have a branched chain shape. Specifically, methyl group, ethyl group, propylene group, isopropyl group, isobutyl group, tert-butyl group, n-butyl group, pentyl group, hexyl group, heptyl group, octyl group, 2-ethylhexyl group, dodecyl group, A benzyl group etc. are mentioned.
R ² is a nitrile group (—CN) or an ester group (—COOR ³ ). As R < ³ >, the C1-C20 alkyl group or aralkyl group which may have a substituent is mentioned. Specific examples of R ³ include those exemplified for R ¹ and the β-cyanoethyl group, β-chloroethyl group, ethoxypropyl group, hydroxyalkyl group, alkoxyalkoxyalkyl group, and alkoxyalkyl group. However, when R ¹ is a methyl group, R ³ is not an ethyl group.

  The dye lens of the present invention is obtained by dyeing at least one surface of a plastic substrate serving as a lens substrate with a dye solution containing a compound represented by the above general formula [I].

Plastic base materials are, for example, transparent plastics such as acrylic resins, thiourethane resins, methacrylic resins, allyl resins, episulfide resins, polycarbonate resins, polyurethane resins, polyester resins, polyester resins, and polystyrene resins. Resin, episulfide resin, polyethersulfone resin poly-4-methylpentene-1 resin, diethylene glycol bisallyl carbonate resin (CR-39), polyvinyl chloride resin, allyl diglycol carbonate resin, halogen-containing copolymer, sulfur-containing copolymer It is formed of a polymer or the like.
Moreover, in this embodiment, as a refractive index (nd) of a plastic base material, what was selected from 1.50, 1.60, 1.67, and 1.74 is used, for example. When the refractive index of the plastic substrate is 1.60 or more, allyl carbonate resin, acrylate resin, methacrylate resin, thiourethane resin, episulfide resin, etc. should be used as the plastic substrate. Is preferred.

  In the present invention, the composition of the staining solution used for dyeing the plastic substrate is not particularly limited as long as it contains the compound represented by the above general formula [I], but the compound represented by the above general formula [I] And a binder resin and a solvent. It is also preferred that the dyeing solution further contains a dye.

  The content of the compound represented by the general formula [I] in the staining liquid is not particularly limited, but is preferably 0.01% by mass to 10% by mass, and more preferably 0.05% by mass to 5% by mass. By setting the content of the compound represented by the general formula [I] in the staining solution in the above range, it is possible to obtain a dyed lens having an effective short wavelength cutting ability and less coloring.

In the present invention, the binder resin contained in the dyeing solution includes vinyl chloride resin, vinyl acetate resin, polyamide, polyethylene, polycarbonate, polystyrene, phenol resin, polypropylene, fluororesin, butyral resin, melamine resin, polyvinyl alcohol, and cellulose resin. Alkyd resin, acrylic resin, epoxy resin, urethane resin, polyester resin, silicon resin and the like. These resins can be used singly or in combination of two or more, and a copolymer can also be used.
Although content in particular of binder resin in a dyeing liquid is not restrict | limited, 0.01 mass%-5 mass 5 are preferable, and 0.05 mass%-3 mass% are more preferable. By setting the content of the binder resin in the dyeing liquid in the above range, workability at the time of dyeing at least one surface of a plastic base material to be a lens base material is improved.

In the present invention, the dyes that may be contained in the dyeing liquid include disperse dyes, reactive dyes, direct dyes, composite dyes, acid dyes, metal complex dyes, vat dyes, sulfur dyes, azo dyes, fluorescent dyes, resin coloring Dyes, other functional dyes, and the like. Other than these, any dye can be used without particular limitation. These dyes may be used alone or in combination of two or more.
When the dyeing solution contains a dye, the content of the dye in the dyeing solution can be 0.1 to 99.9% by mass, preferably 0.001 to 10% by mass, and more preferably. Is 0.01% by mass to 5% by mass. When the content of the dye in the dyeing liquid is less than the above range, it may be difficult to obtain a sufficient dyed lens. Moreover, when there is more dye than the said range, depending on dye, aggregation etc. may arise and it may become difficult to use.

  In the present invention, examples of the solvent contained in the staining solution include methanol, ethanol, methyl ethyl ketone, ethylene glycol monoethyl ether, acetone, isobutyl alcohol, ethyl ether, chlorobenzene, isobutyl acetate, isopropyl acetate, isopentyl acetate, ethyl acetate, acetic acid. Butyl, pentyl acetate, methyl acetate, cyclohexanol, 1,4-dioxane, N, N-dimethylformamide, tetrahydrofuran, 1,1,1-trichloroethane (methyl chloroform), toluene, 1-butanol, 2-butanol, methyl isobutyl Ketones, methylcyclohexanone, methylbutylketone, acetophenone, benzoic acid ester, methylcyclohexane and the like, and the compounds and dyes represented by the above general formula [I] As long as they are partial dissolution may be any, as may be used singly or as a mixture of two or more thereof.

  Various additives such as a pH adjusting agent, a viscosity adjusting agent, a leveling agent, a matting agent, a stabilizer, an ultraviolet absorber, and an antioxidant may be used in combination in the staining solution as necessary.

Examples of a method for dyeing at least one surface of a plastic substrate using a dyeing solution containing the compound represented by the above general formula [I] to obtain a dyed lens include the following two methods.
(1) Method of coating the surface of a plastic substrate (lens) with a dyeing solution and heating to dye the lens surface in the dyeing solution (coating method)
(2) Method of dyeing the lens surface by immersing a plastic substrate (lens) in the dyeing solution (dip method)
Of these two methods, the coating method (1) is preferred because the amount of dyeing solution used is small and production costs can be reduced.

  As a method for coating (coating) the dyeing liquid onto the plastic substrate in the coating method, a usual coating method such as brush coating, dip coating, spin coating, roll coating, spray coating, flow coating, or ink jet coating can be used. . As for the coated surface, it may be coated on one side of a plastic substrate (lens) or may be coated on both sides in order to further increase the dyeing density. The coating thickness of the dyeing liquid on the plastic substrate is not particularly limited and can be appropriately adjusted. For example, the coating thickness can be in the range of 0.01 μm to 10 μm.

  In the dyeing by the coating method, when dyeing (coloring processing) with a uniform dyeing concentration on the entire surface of the plastic substrate (lens), the lens liquid is coated on the lens surface and then heat-treated, so that It is preferable that the compound represented by the above general formula [I] and the dye penetrate and diffuse on the lens surface. As heating conditions for the plastic substrate (lens) coated with the staining solution, the heating temperature is preferably 70 ° C. to 180 ° C., and the heating time is preferably 10 to 180 minutes. As a heating method, in addition to air oven heating, far infrared irradiation heating, UV irradiation heating, or the like can also be used.

  In the case of dyeing by coating method, when dyeing (coloring processing) with a gentle density gradient on a plastic substrate (lens substrate), after coating the lens with a staining solution, the coating solution surface (staining solution surface) Is heated while gradually changing the heating region, the amount of dye corresponding to the density gradient can be permeated into the lens substrate.

  After heat-treating the plastic substrate (lens substrate) coated with the staining solution, the lens substrate is washed to remove the coating layer (the applied staining solution) on the lens substrate surface. The dyeing lens of the invention can be obtained. The method for cleaning the lens substrate after the heat treatment is not particularly limited as long as the coating layer (the applied dyeing solution) on the surface of the lens substrate can be removed, but wiping with an organic solvent or cleaning with an alkaline cleaner is preferable. . Among these, it is more preferable to wipe off using acetone or methyl ethyl ketone as the organic solvent.

When dyeing a plastic substrate (lens substrate) by the dip method, the compound represented by the above general formula [I] in the staining solution is immersed in the staining solution by immersing the lens substrate in the staining solution and A dyed lens can be obtained by penetrating and diffusing the dye.
In dyeing by the dip method, it is preferable to immerse the lens substrate in a dyeing liquid heated to 80 ° C. to 95 ° C.
The dyed lens of the present invention can be obtained by washing the lens substrate after the immersion, for example, by washing with water or wiping with a solvent to remove the dyeing solution adhering to the outer surface of the lens.

  The dyed lens of the present invention is dyed with the compound represented by the above general formula [I], so that the general formula [I] is introduced from the surface of the plastic base material (lens base material) to the inside of the lens base material. The compound represented by is penetrating and diffusing.

The dyeing lens of the present invention effectively cuts light in the short wavelength region (380 nm to 450 nm) of visible light, and is excellent in short wavelength light absorption performance.
Further, the dyed lens of the present invention has a light transmittance (%) converted to a thickness of 2 mm, plotted against the wavelength (nm), the light transmittance (%) as the vertical axis, and the wavelength (nm) as the horizontal axis. It can also have spectral characteristics in which the average slope of the rate curve (light transmittance curve, spectral transmittance curve) in the wavelength range of 420 nm to 440 nm is in the range of 0.7 to 3.0 (% / nm). Here, the light transmittance curve shows what was obtained by measuring the transmittance curve of the dyed lens and then converting it to the transmittance per 2 mm of the lens thickness. The light transmittance at the center of the lens is measured, and a transmittance curve in which the light transmittance (%; vertical axis) is plotted with respect to the wavelength (nm; horizontal axis) can be used as it is.

In the present invention, the “average slope of the transmittance curve at wavelengths from ₄₂₀ nm to 440 nm” means that the light transmittance at a wavelength of 420 nm is T ₄₂₀ (%) and the light transmittance at a wavelength of 440 nm is T ₄₄₀ (%). And represented by the following formula (A).
Average slope (% / nm) = (T ₄₄₀ −T ₄₂₀ ) / (440−420) Expression (A)

  The dyeing lens of the present invention having such light transmission performance is capable of absorbing short-wavelength light of 380 nm to 450 nm, which is said to cause and cause damage to the retina and the like, eye diseases, flickering of vision, and contrast reduction. Since it is particularly excellent, it is particularly suitable as a spectacle lens.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to a following example.

Example 1
A dyeing solution was prepared from the compound represented by the above general formula [I], a dye, a binder resin, and a solvent. Kayalon Polyester Yellow AL Dye 0.1% by weight as Yellow Dye, Kayalon Polyester Red AUL-S Dye 0.2% by weight as Red Dye, Kayalon Polyester Blue AUL-S Dye as Blue Dye (Made by Yakuhin Co., Ltd.) 0.3% by mass, 0.5% by mass of the compound represented by R ¹ = —CH ₃ and R ² = —CN in the above general formula [I], 20% by mass of polyvinyl alcohol, 73% by mass of methyl ethyl ketone The dyeing solution was prepared by stirring all day and night.

  The prepared staining solution is spin-coated on the entire surface of a plastic lens having a refractive index of 1.67 (manufactured by Nikon Essilor, Nikonlite 4AS, size 80φ, center thickness 2 mm), and a coating layer having a thickness of about 0.3 μm is formed. Formed. A plastic lens having a coating layer formed on the surface was heated in an air oven at 150 ° C. for 2 hours, and the lens surface was dyed by allowing the dye and the compound represented by the above general formula [I] to permeate and diffuse. Thereafter, the lens was cooled and wiped with acetone to remove the surface resin layer (coat layer).

  Next, a urethane-based impact resistance improving coat having a thickness of about 1 μm and a silicone-based scratch resistance improving hard coat having a thickness of about 2 μm were formed on the surface of the dyed plastic lens. Further thereon, a multilayer lens antireflection coating formed of an inorganic oxide having a thickness of about 0.3 μm was formed by vacuum deposition to obtain a dyed lens.

  The spectral transmittance at the center of the obtained dyed lens was measured, and the transmittance curve is shown in FIG. As a result, the stained lens of Example 1 effectively cuts short-wavelength light with a wavelength of 380 nm to 450, and the average slope of the transmittance curve at a wavelength of 420 nm to 440 nm was 1.9 (% / nm). .

(Comparative Example 1)
A dyeing solution was prepared from a dye, a binder resin, and a solvent. Kayalon Polyester Yellow AL 0.1% by weight as yellow dye, Kayalon Polyester Red AUL-S dye 0.2% by weight as red dye, Kayalon Polyester Blue AUL-S dye as blue dye (all dyes are Nippon Kayaku Co., Ltd.) A dyeing solution was prepared by stirring 0.3% by mass of (made by company) with 20% by mass of polyvinyl alcohol and 73.5% by mass of methyl ethyl ketone all day and night.

  The prepared staining solution is spin coated on the entire surface of a plastic lens (Nikon Essilor, Nikonlite 4AS, size 80φ, center thickness 2 mm) having a refractive index of 1.67 to form a coating layer having a thickness of about 0.3 μm. did. The plastic lens having a coating layer formed on the surface was heated in an air oven at 150 ° C. for 2 hours to allow the dye to penetrate and diffuse into the lens surface to stain the lens surface. Thereafter, the lens was cooled and wiped with acetone to remove the surface resin layer (coat layer).

  Next, on the surface of the plastic lens dyed in the same manner as in Example 1, a urethane-based impact resistance improving coat having a thickness of about 1 μm and a silicone-based scratch resistance improving hard coat having a thickness of about 2 μm were formed. Further, a multilayer lens antireflection coating formed of an inorganic oxide having a thickness of about 0.3 μm was formed thereon by vacuum vapor deposition to obtain a dyed lens.

  The spectral transmittance at the center of the obtained dyed lens was measured, and the transmittance curve is shown in FIG. As a result, the short wavelength light having a wavelength of 430 nm or less was not effectively cut in the stained lens of Comparative Example 1, and the average slope of the transmittance curve at a wavelength of 420 nm to 440 nm was 0.6 (% / nm). .

(Example 2)
By mixing the compounds shown in Table 1 with R ¹ = -CH ₃ and R ² = -CN in the above general formula [I], polyvinyl alcohol, and methyl ethyl ketone, and stirring for a whole day and night, the dyeing solution Was prepared.

  The prepared dyeing solution is spin-coated on the entire surface of one side of a plastic lens (Nikon Essilor, Nikonlite 3AS, size 75φ, center thickness 2 mm) with a refractive index of 1.60 to form a coating layer having a thickness of about 0.3 μm. did. The plastic lens having a coating layer formed on the surface was heated in an air oven at 150 ° C. for 2 hours to dye the lens surface. Thereafter, the lens was cooled and wiped with acetone to remove the surface resin layer (coat layer).

  Next, a dyed lens was obtained by depositing an impact resistance improving coat, a scratch resistance improving hard coat and a multilayer antireflection coating on the surface of a plastic lens dyed in the same manner as in Example 1.

The spectral transmittance at the center of the obtained dyed lens was measured, and the transmittance curve is shown in FIG. The average slope of the transmittance curve of each sample at wavelengths of 420 nm to 440 nm is also shown in Table 1.
From the results shown in FIG. 2 and Table 1, the stained lenses of Sample 1 to Sample 6 stained with the staining liquid containing the compound represented by the above general formula [I] are effective in using short wavelength light with a wavelength of 380 nm to 450 nm. I was cutting it.

(Example 3)
A dyeing solution is prepared by stirring 0.5 parts by mass of the compound of the above general formula [I] where R ¹ = -CH ₃ and R ² = -CN with 20 parts by mass of polyvinyl alcohol and 73 parts by mass of methyl ethyl ketone overnight. did.

  The prepared dyeing solution is spin-coated on the entire surface of one side of a plastic lens (Nikon Essilor, Nikonlite 3AS, size 75φ, center thickness 2 mm) with a refractive index of 1.60 to form a coating layer having a thickness of about 0.3 μm. did. The plastic lens having a coating layer formed on the surface was heated in an air oven at 150 ° C. for 2 hours to dye the lens surface. Thereafter, the lens was cooled and wiped with acetone to remove the surface resin layer (coat layer).

  Next, a dyed lens was obtained by depositing an impact resistance improving coat, a scratch resistance improving hard coat and a multilayer antireflection coating on the surface of a plastic lens dyed in the same manner as in Example 1.

Example 4
The same method and procedure as in Example 3 except that the compounding amount of R ¹ = -CH ₃ and R ² = -CN in the above general formula [I] in the staining solution was changed to 1.0 part by mass. A dyed lens was obtained.

(Example 5)
In the above general formula [I], 0.5 parts by mass of a compound in which R ¹ = —CH ₃ , R ² = —COOC ₂ H ₅ is stirred overnight with 20 parts by mass of polyvinyl alcohol and 73 parts by mass of methyl ethyl ketone. A liquid was prepared.

  The prepared dyeing solution is spin-coated on the entire surface of one side of a plastic lens (Nikon Essilor, Nikonlite 3AS, size 75φ, center thickness 2 mm) with a refractive index of 1.60 to form a coating layer having a thickness of about 0.3 μm. did. The plastic lens having a coating layer formed on the surface was heated in an air oven at 150 ° C. for 2 hours to dye the lens surface. Thereafter, the lens was cooled and wiped with acetone to remove the surface resin layer (coat layer).

  Next, a dyed lens was obtained by depositing an impact resistance improving coat, a scratch resistance improving hard coat and a multilayer antireflection coating on the surface of a plastic lens dyed in the same manner as in Example 1.

(Example 6)
The general formula in staining solution except for changing the amount of _{^{R 1 = -CH 3, R 2}} = -COOC 2 H 5 , compound 1.0 part by mass in [I] is the same as in Example 5 A dyed lens was obtained by the method and procedure.

(Comparative Example 2)
Without dyeing, on the surface of a plastic lens having a refractive index of 1.60 (Nikon Essilor, Nikonlite 3AS, size 75φ, center thickness 2 mm), the impact resistance improving coating and scratch resistance were the same as in Example 1. A plastic lens without dyeing was obtained by forming a property improving coat and a multilayer antireflection coating.

  With respect to the obtained stained lenses of Examples 3 to 6 and the plastic lens of Comparative Example 2, the spectral transmittance at the center of the lens was measured, and the transmittance curve is shown in FIG. Table 2 shows the average slopes of the transmittance curves of the stained lenses of Examples 3 to 6 and the plastic lens of Comparative Example 2 at wavelengths of 420 nm to 440 nm. As a result, the dyed lenses of Examples 3 to 6 effectively cut short wavelength light having a wavelength of 380 nm to 450 nm.

(Example 7)
Kayalon polyester yellow AL dye 0.5% by weight as yellow dye, Kayalon polyester red AUL-S dye 1.1% by weight as red dye, Kayalon polyester blue AUL-S dye 0.7% by weight as blue dye (any Of Nippon Kayaku Co., Ltd.), 0.5 part by mass of the compound represented by R ¹ = —CN and R ² = —COOC ₂ H ₅ in the above general formula [I], 20 parts by mass of polyvinyl alcohol, and methyl ethyl ketone 73 The dyeing solution was prepared by stirring with parts by mass overnight.

  The prepared staining solution is spin coated on the entire surface of a plastic lens (Nikon Essilor, Nikonlite 4AS, size 80φ, center thickness 2 mm) having a refractive index of 1.67 to form a coating layer having a thickness of about 0.3 μm. did. The plastic lens having a coating layer formed on the surface was heated in an air oven at 150 ° C. for 2 hours to dye the lens surface. Thereafter, the lens was cooled and wiped with acetone to remove the surface resin layer (coat layer).

  Next, a dyed lens was obtained by depositing an impact resistance improving coat, a scratch resistance improving hard coat and a multilayer antireflection coating on the surface of a plastic lens dyed in the same manner as in Example 1.

  The spectral transmittance at the center of the obtained dyed lens was measured, and the transmittance curve is shown in FIG. As a result, the stained lens of Example 7 effectively cuts short-wavelength light with a wavelength of 380 nm to 450 nm, and the average slope of the transmittance curve at a wavelength of 420 nm to 440 nm was 1.6 (% / nm). .

(Comparative Example 3)
A dyed lens was obtained by the same method and procedure as in Example 7 except that the compound represented by the above general formula [I] was not blended in the dyeing solution.

  The spectral transmittance at the center of the obtained dyed lens was measured, and the transmittance curve is shown in FIG. As a result, in the stained lens of Comparative Example 3, short wavelength light with a wavelength of 380 nm to 450 nm was not effectively cut, and the average slope of the transmittance curve at a wavelength of 420 nm to 440 nm was 0.3 (% / nm). It was.

(Example 8)
A dyeing solution is prepared by stirring 0.5 parts by mass of the compound of the above general formula [I] where R ¹ = -CH ₃ and R ² = -CN with 20 parts by mass of polyvinyl alcohol and 73 parts by mass of methyl ethyl ketone overnight. did.

  The prepared staining solution was spin-coated on the entire surface of a plastic lens having a refractive index of 1.60 (Nikon Essilor, Nikonlite 3AS, size 75φ, center thickness 2 mm) to form a coating layer having a thickness of about 0.3 μm. . The plastic lens having a coating layer formed on the surface was heated in an air oven at 150 ° C. for 2 hours to dye the lens surface. Thereafter, the lens was cooled and wiped with acetone to remove the surface resin layer (coat layer).

  Next, a dyed lens was obtained by depositing an impact resistance improving coat, a scratch resistance improving hard coat and a multilayer antireflection coating on the surface of a plastic lens dyed in the same manner as in Example 1.

  The spectral transmittance at the center of the obtained dyed lens was measured, and the transmittance curve is shown in FIG. As a result, the stained lens of Example 8 effectively cuts short-wavelength light with a wavelength of 380 nm to 450 nm, and the average slope of the transmittance curve at a wavelength of 420 nm to 440 nm was 2.1 (% / nm). .

(Comparative Example 4)
Instead of the compound represented by the above general formula [I], 1.5 parts by mass of Kayalon Polyester Yellow AL dye (manufactured by Nippon Kayaku Co., Ltd.), which is a dye having a blue light (short wavelength light) absorption ability, A dyed lens was obtained by the same method and procedure as in Example 8 except that the dyeing solution was prepared by blending.

  The spectral transmittance at the center of the obtained dyed lens was measured, and the transmittance curve is shown in FIG. As a result, the stained lens of Comparative Example 4 is somewhat cut in the short wavelength region of visible light (short wavelength light of wavelength 380 nm to 450 nm), but also has absorption in the vicinity of wavelength 450 nm to 500 nm, and the dyeing of Example 8 Compared with the lens, it was yellowish. The average slope of the transmittance curve of the stained lens of Comparative Example 4 at a wavelength of 420 nm to 440 nm was 0.4 (% / nm).

Claims (4)

Compound represented by the following general formula [I] (wherein R ¹ may be an alkyl group or aralkyl group which may be branched, R ² may be —CN or —COOR ³ , and R ³ may have a substituent) A dyed lens characterized by being dyed using an alkyl group or an aralkyl group (excluding an ethyl group when R ¹ is a methyl group).

  The average slope at a wavelength of 420 nm to 440 nm of the transmittance curve in which the light transmittance (%) converted to a thickness of 2 mm is plotted with respect to the wavelength (nm) is in the range of 0.7 to 3.0 (% / nm). The dyeing lens according to claim 1.   The dyeing lens according to claim 1, wherein the dyeing lens is dyed with the compound represented by the general formula [I] and a dye. A method for producing the dyed lens according to any one of claims 1 to 3,
A method for producing a dyed lens, comprising dyeing at least one surface of a plastic substrate with the compound represented by the general formula [I].

Images