JP7083350B2 - Plastic base material, plastic lens - Google Patents

Description

The present disclosure relates to a plastic substrate and a plastic lens.

As a plastic base material having a high cut rate of blue light, there is a plastic base material containing a benzotriazole compound (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-148877

The present disclosure relates to a plastic base material containing a compound represented by the formula (1) described later, and a plastic lens containing the plastic base material.

Hereinafter, the plastic base material and the plastic lens of the present embodiment will be described in detail.
In addition, in this specification, "-" is used in the meaning which includes the numerical values described before and after it as the lower limit value and the upper limit value.

From the viewpoint of improving visibility and contrast and reducing eye health hazards such as blue light hazards, it is desired that the plastic substrate has excellent visual transmittance and blue light blocking ability. There is. Here, the blue light is intended to be light in the wavelength range of 380 to 500 nm.
The plastic base material and the plastic lens of the present embodiment are excellent in visual transmittance and also excellent in blue light blocking ability.
In the following, first, the components contained in the plastic base material will be described in detail.

<Compound represented by the formula (1)>
The plastic substrate contains a compound represented by the formula (1). The compound represented by the formula (1) is a so-called benzotriazole-based compound, and has excellent blue light absorption characteristics. Therefore, with a small amount of use, an excellent blue light-cutting ability can be imparted to the plastic base material, and a reduction in the visual transmittance can be prevented.

In the formula, R ¹ and R ³ each independently represent a hydrogen atom or an alkoxy group. However, at least one of R ¹ and R ³ represents an alkoxy group.
The number of carbon atoms of the alkoxy group is not particularly limited, but 1 to 12 is preferable, 1 to 6 is more preferable, 1 to 3 is further preferable, and 1 is particularly preferable.
Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group, and a nonyloxy group.

R ² represents a hydrogen atom, an alkyl group or an alkoxy group. Of these, a hydrogen atom is preferable.
The number of carbon atoms of the alkyl group is not particularly limited, but 1 to 12 is preferable, 1 to 6 is more preferable, 1 to 3 is further preferable, and 1 is particularly preferable.
Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, and an n-. Examples thereof include an octyl group, a 1,1,3,3-tetramethylbutyl group and a nonyl group.
The preferred embodiment (carbon number, specific example) of the alkoxy group is the same as the preferred embodiment (carbon number, specific example) of the alkoxy group represented by R ¹ and R ³ above.

Among them, as the compound represented by the formula (1), one of R ¹ and R ³ represents an alkoxy group, the other of R ¹ and R ³ represents a hydrogen atom, and R ² represents a hydrogen atom. Aspects are mentioned. More specifically, R ¹ in the formula (1) represents an alkoxy group, R ³ represents a hydrogen atom, and R ² represents a hydrogen atom, and R ¹ in the formula (1) represents a hydrogen atom. It is preferable that R 3 represents a hydrogen atom, R ³ represents an alkoxy group, and R ² represents a hydrogen atom.

The content of the compound represented by the formula (1) contained in the plastic base material is not particularly limited, but the resin described later is described in that the balance between the visual permeability of the plastic base material and the blue light blocking ability is better. With respect to 100 parts by mass, 0.01 to 1.5 parts by mass is preferable, 0.05 to 1.0 part by mass is more preferable, and 0.05 to 0.5 parts by mass is further preferable.

<Resin>
The plastic substrate preferably contains a resin. The resin functions as a matrix for dispersing the compound represented by the formula (1).
The type of resin is not particularly limited, and examples thereof include thiourethane resin, urethane resin, episulfide resin, polycarbonate resin, polyamide resin, acrylic resin, vinyl resin, and polyester resin. Among them, when the plastic base material is used for the plastic lens, the resin is preferably at least one selected from the group consisting of thiourethane resin, urethane resin, and episulfide resin, and is preferably thiourethane resin. More preferred.

The thiourethane resin is obtained by reacting a polyisocyanate compound with a polythiol compound.
The polyisocyanate compound is a compound having two or more isocyanate groups. The type of the polyisocyanate compound is not particularly limited, and examples thereof include known compounds. For example, 3-isocyanatemethyl-3,5,5-trimethylcyclohexylisocyanate, 4,4'-methylenebis (cyclohexylisocyanate), 1,3- or 1,4-bis (isocyanatemethyl) cyclohexane, and bis (isocyanatemethyl). ) Alicyclic polyisocyanate compounds such as bicyclo [2,2,1] heptane; aromatic polyisocyanate compounds such as diphenylmethane diisocyanate, phenylenediisocyanate, and naphthalenediocyanate; 1,3-xylylene diisocyanate, and 1,4. -Aromatic aliphatic polyisocyanate compounds such as xylylene diisocyanate; aliphatic polyisocyanate compounds such as hexamethylene diisocyanate (HDI) can be mentioned.
Of these, bis (isocyanatemethyl) bicyclo [2,2,1] heptane or 1,3-xylylene diisocyanate is preferable.

From the viewpoint of pot life, the isocyanate group of the polyisocyanate compound may be protected by a blocking agent.

The polythiol compound is a compound having two or more thiol groups. The type of the polythiol compound is not particularly limited, and examples thereof include known compounds. For example, ethylene glycol bis (3-mercaptopropionate), trimethylolpropanebis (2-mercaptoacetate), trimethylolpropanebis (3-mercaptopropionate), pentaerythritol tetrakis (2-mercaptoacetate), pentaerythritol. Aliphatic polythiol compounds such as tetrakis (3-mercaptopropionate), 4-mercaptomethyl-3,6-dithia-1,8-octanedithiol, and tetrakis (mercaptomethyl) methane; 1,3,5-tri Mercaptobenzene, 1,2,3-tris (mercaptomethyl) benzene, 1,2,4-tris (mercaptomethyl) benzene, 1,3,5-tris (mercaptomethyl) benzene, 1,2,3-tris ( Mercaptoethyl) benzene, 1,2,4-tris (mercaptoethyl) benzene, 1,3,5-tris (mercaptoethyl) benzene, 2,5-toluenedithiol, 3,4-toluenedithiol, 1,3-di (P-methoxyphenyl) Benzene-2,2-dithiol, 1,3-diphenylpropane-2,2-dithiol, phenylmethane-1,1-dithiol, and 2,4-di (p-mercaptophenyl) pentane Examples thereof include aromatic polythiol compounds such as.
The aliphatic polythiol compound and the aromatic polythiol compound may have a sulfur atom in addition to the thiol group.

The content of the resin contained in the plastic base material is not particularly limited, but 90 mass with respect to the total mass of the plastic base material in that the balance between the visual transmittance of the plastic base material and the blue light blocking ability is better. % Or more is preferable, and 95% by mass or more is more preferable. The upper limit is not particularly limited and may be 99.99% by mass or less.

The plastic base material may contain components other than the compound represented by the above formula (1) and the resin. Other components include, for example, internal mold release agents, light stabilizers, fillers, antioxidants, optical brighteners, brewing agents, polymerization catalysts, dyes and the like.

The refractive index of the plastic substrate is not particularly limited, and is preferably 1.55 or more, more preferably 1.60 or more. The upper limit is not particularly limited and may be 1.70 or less.
The above-mentioned refractive index is a refractive index at a wavelength of 546.1 nm, and the refractive index is measured using a precision refractometer KPR-20 manufactured by Carnew Optical Industry Co., Ltd.

The thickness of the plastic base material is not particularly limited, and may be, for example, about 1 to 30 mm from the viewpoint of handleability.
The shape of the plastic base material is not particularly limited. For example, when applied to a plastic lens for eyeglasses, the shape of the plastic base material has a convex surface on the object side (object side surface) and an eyeball side surface (eyeball side surface). A meniscus shape with a concave surface is common.

The method for producing the plastic base material is not particularly limited, and a known method can be adopted.
For example, a method of mixing a compound represented by the formula (1) with a monomer forming a resin to form a composition and polymerizing the monomer in the composition can be mentioned. The polymerization method is not particularly limited, but when forming a plastic lens, cast polymerization is preferable.
For example, a composition containing a compound represented by the formula (1), a polythiol compound, and a polyisocyanate compound is prepared, and this composition is injected into a lens molding mold at a predetermined temperature (for example, −20). By heating at ~ 150 ° C.), a plastic substrate containing the compound represented by the formula (1) and the thiourethane resin can be obtained.
As another method for producing the plastic base material, the plastic base material is immersed in a liquid in which the compound represented by the formula (1) and the surfactant are dissolved or dispersed in water, and the formula (1) is used. Also mentioned is a method of infiltrating the represented compound into a plastic substrate.

The plastic base material containing the compound represented by the formula (1) can be applied to various uses, and is preferably applied to a plastic lens, more preferably to a plastic lens for eyeglasses.
The plastic lens may contain the above-mentioned plastic base material, and may contain another functional layer on the plastic base material.
When the plastic lens is for spectacles, the functional layer may be arranged on one surface of the object side surface and the eyeball side surface of the plastic substrate, or may be arranged on both surfaces.
Examples of the functional layer include one or more layers selected from the group consisting of a primer layer, a hard coat layer, an antireflection layer, and a water- and oil-repellent layer. The functional layer may include a plurality of the above layers.

The primer layer is a layer that is arranged between the two layers and improves the adhesion between the two layers.
The material constituting the primer layer is not particularly limited, and examples thereof include known materials.

The hard coat layer is a layer that imparts scratch resistance to a plastic lens. In addition, in this specification, a hard coat layer is defined as having the hardness of "H" or more by the pencil hardness by the test method defined in JIS K5600.
As the hard coat layer, a known hard coat layer can be used, and examples thereof include an organic hard coat layer, an inorganic hard coat layer, and an organic-inorganic hybrid hard coat layer.

The antireflection layer is a layer having a function of preventing reflection of incident light. In the present specification, the antireflection layer is defined as a layer exhibiting a reflection characteristic in which the reflectance is reduced to about 5% or less in the visible light region of 400 to 700 nm.
The structure of the antireflection layer is not particularly limited, and may be a single-layer structure or a multi-layer structure.
In the case of a multi-layer structure, a structure in which low refractive index layers and high refractive index layers are alternately laminated is preferable. Examples of the material constituting the high refractive index layer include titanium, zirconate, aluminum, tantalum, and lanthanum oxide. Further, as a material constituting the low refractive index layer, silica and the like can be mentioned.

The water- and oil-repellent layer can reduce the surface energy of the plastic lens and impart the function of preventing contamination to the plastic lens.
The water- and oil-repellent layer contains a water- and oil-repellent component. The type of the water-repellent and oil-repellent component is not particularly limited, and examples thereof include a fluorine-containing compound, a silicone compound, and a compound having a long-chain alkyl group.

The plastic base material constituting the plastic lens is preferably transparent. Transparency is intended to have a visual transmittance of 82.0% or more.
Further, the visual transmittance of the plastic lens in which the functional layer is arranged on at least one of the side surface of the object and the side surface of the eyeball is preferably 94.0% or more, more preferably 95.5% or more. preferable. The upper limit is not particularly limited and may be 99.9%.
In the present application, the visual transmittance is defined as Y (%) using the tristimulus value Y in the CIE color system, and the spectral transmittance of the plastic lens is measured by the spectrophotometer U4100 manufactured by Hitachi High-Technologies. , D65 Light source Y is adopted in a 10 ° field of view.

The light ray cut rate in the wavelength range of 380 to 500 nm of the plastic base material constituting the plastic lens is preferably 29.0% or more, more preferably 40.0% or more, and 50.0% or more. It is more preferable to have. The upper limit is not particularly limited and may be 60.0% or less.
The light ray cut rate in the wavelength range of 380 to 500 nm of the plastic lens is preferably 20.0% or more, more preferably 30.0% or more, still more preferably 40.0% or more. The upper limit is not particularly limited and may be 60.0% or less.
The method for measuring the light transmittance is first represented by the following equation weighted by the irradiance distribution of sunlight (under the environment of Air Mass 2.0) and its radiation spectral risk (blue light hazard and its function). The spectral transmittance τ _sb (wavelength range 380 to 500 nm, 5 nm pitch) is calculated.

In the above equation, τ (λ) represents the transmittance, _ESλ (λ) represents the spectral irradiance of sunlight, and B (λ) represents the blue light hazard function.
Further, in the above equation, WB _λ (λ) represents a weighting function, and the weighting function is described in JIS T7333: 2005 Annex CC. It is described in paragraph 1.

Next, the value obtained by (100-τ _sb ) is taken as the light ray cut rate (%).

Hereinafter, the plastic substrate and the plastic lens will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

The visual transmittance and the light ray cut rate (blue light cut rate) in the wavelength range of 380 to 500 nm in Examples and Comparative Examples described later were measured by the above-mentioned method.

<Example 1>
Bis (isocyanis methyl) bicyclo [2,2,1] heptane (50.6 parts by mass) as a polyisocyanate compound, and pentaerythritol tetrakis (3-mercaptopropionate) (23.9 parts by mass) and 4 as polythiol compounds. -Mercaptomethyl-3,6-dithia-1,8-octanedithiol (25.5 parts by mass), dibutyltin dichloride (0.08 parts by mass) as a polymerization catalyst, and internal release containing a phosphate ester as a main component. The agent (0.1 part by mass) and 2- (2'-hydroxy-5'-methoxyphenyl) -5-chlorobenzotriazole as an ultraviolet absorber were mixed uniformly to prepare a composition. .. The 2- (2'-hydroxy-5'-methoxyphenyl) -5-chlorobenzotriazole is 0.09 parts by mass with respect to the total mass (100 parts by mass) of the polyisocyanate compound and the polythiol compound. used.
Next, after degassing the obtained composition, the degassed composition was injected into a glass mold and subjected to thermal polymerization curing. After the curing was completed, the mold was released, the obtained plastic substrate was washed, and further annealed.
Then, a primer layer, a hard coat layer and an antireflection layer were arranged in this order on both sides of the obtained plastic base material to obtain an evaluation lens.
The procedure for forming the primer layer, the hard coat layer and the antireflection layer was as follows.
Specifically, by the dipping method, a urethane-based impact resistance improving coat (primer layer) with a thickness of about 1 μm and a silicone-based scratch resistance improving hard coat (hard coat) with a thickness of about 2 μm are applied to the surface of the plastic base material. Layers) and were laminated in this order.
Next, a multilayer film antireflection coating (antireflection layer) made of an inorganic oxide having a thickness of about 0.3 μm was formed on a silicone-based scratch-resistant hard coat by a vacuum vapor deposition method.

As a result of measuring the spectral transmittance at the center of the lens of the obtained plastic substrate, the visual transmittance at 2.0 mm thickness was 88.8%, and the blue light cut rate (light ray cut rate in the wavelength range of 380 to 500 nm). Was 31.0%.
As a result of measuring the spectral transmittance at the center of the obtained evaluation lens, the visual transmittance of the S-0.00 (D) lens 2.0 mm thick was 97.0%, and the blue light cut rate (380 to 380 to). The light cut rate in the wavelength range of 500 nm) was 25.1%.
2- (2'-Hydroxy-5'-methoxyphenyl) -5-chlorobenzotriazole was dissolved in a chloroform solution at a concentration of 10 ppm, and the obtained solution was used for 2- (2'-hydroxy-5. The maximum absorption wavelength of ′ -methoxyphenyl) -5-chlorobenzotriazole was measured and found to be 366 nm.

<Examples 2 to 6>
An evaluation lens was prepared according to the same procedure as in Example 1 except that the amount of 2- (2'-hydroxy-5'-methoxyphenyl) -5-chlorobenzotriazole was changed to the value shown in Table 1. Then, various evaluations were carried out.

<Example 7>
M-xylylene diisocyanate (52.1 parts by mass) as a polyisocyanate compound, 4-mercaptomethyl-3,6-dithia-1,8-octanedithiol (47.9 parts by mass) as a polythiol compound, and dibutyltin as a polymerization catalyst. An evaluation lens was prepared and various evaluations were carried out according to the same procedure as in Example 1 except that dichloride (0.01 parts by mass) was used.

<Example 8>
As episulfide compounds, bis (β-epithiopropyl) sulfide (78.5 parts by mass), sulfur powder (reagent with a purity of 98% or more) (14.3 parts by mass), and xylylene thiol (2.5 parts by mass). , 2- (2'-Hydroxy-5'-methoxyphenyl) -5-chlorobenzotriazole (0.07 parts by mass) was added as an ultraviolet absorber, and the mixture was stirred at 60 ° C. until it was dissolved.
Subsequently, 0.2 parts by mass of 2-mercapto-1-methylimidazole was added to this mixed solution as a pre-reaction catalyst, a pre-reaction was carried out at 60 ° C. for 50 minutes, and then the mixture was cooled to 20 ° C.
Next, a solution of triethylbenzylammonium chloride (0.02 parts by mass) as a curing catalyst and dibutyltin dichloride (0.2 parts by mass) as a reaction modifier in xylylene thiol (4.6 parts by mass) was further dissolved. Additions were made to prepare the composition.
After degassing the obtained composition, the degassed composition was poured into a glass mold and subjected to thermal polymerization curing. After the curing was completed, the mold was released, the obtained plastic substrate was washed, and further annealed.
After that, an evaluation lens was prepared and various evaluations were carried out according to the same procedure as in Example 1.

<Comparative Example 1>
Methylenebis (4,1-cyclohexylene) = diisocyanate (58.9 parts by mass) as a polyisocyanate compound and bis (mercaptomethyl) -3,6,9-trithio-1,11-undecandithiol (41. 1 part by mass), dibutyltin dichloride (0.15 part by mass) as a polymerization catalyst, an internal mold release agent containing a phosphoric acid ester as a main component (0.1 part by mass), and 2- (3- (3-part by mass) as an ultraviolet absorber. The mixture was uniformly mixed with tert-butyl-2-hydroxy-5-methylphenyl) -5-chloro-2H-benzotriazole to prepare a composition. In addition, 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chloro-2H-benzotriazole is based on the total mass (100 parts by mass) of the polyisocyanate compound and the polythiol compound. And 0.64 parts by mass was used.
Using the obtained composition, an evaluation lens was prepared according to the same procedure as in Example 1, and various evaluations were carried out.
2- (3-tert-Butyl-2-hydroxy-5-methylphenyl) -5-chloro-2H-benzotriazole was dissolved in a chloroform solution at a concentration of 10 ppm, and the obtained solution was used for 2-. The maximum absorption wavelength of (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chloro-2H-benzotriazole was measured and found to be 353 nm.

<Comparative Example 2>
As an ultraviolet absorber, 2- (4-butoxy-2-hydroxyphenyl) -2H-benzo instead of 2- (2'-hydroxy-5'-methoxyphenyl) -5-chlorobenzotriazole (0.07 parts by mass) An evaluation lens was prepared and various evaluations were carried out according to the same procedure as in Example 8 except that triazole (1.4 parts by mass) was added.

In Table 1, "refractive index" represents the refractive index of the plastic substrate at a wavelength of 546.1 nm. The refractive index was measured using a precision refractometer KPR-20 manufactured by Carnew Optical Industry Co., Ltd.
The "ratio of amount of UV absorber used" is "(amount of UV absorber used (parts by mass)) / (total mass of polyisocyanate compound and polythiol compound (parts by mass))" in Examples 1 to 7. In Example 8, it represents "(amount of ultraviolet absorber used (parts by mass)) / (total mass of bis (β-epitiopropyl) sulfide, xylylene dithiol, and sulfur powder (parts by mass))". .. The total mass of the polyisocyanate compound and the polythiol compound, and the total mass of the bis (β-epitiopropyl) sulfide, the xylylene dithiol, and the sulfur powder are the same as the mass of the resin in the plastic substrate.
In Table 1 below, the evaluation results (visual transmittance, blue light cut rate) of the plastic base material of each example and the comparative example, and the evaluation results (visual transmittance, blue light cut rate) of the evaluation lens are shown. Rate) is shown.

As shown in Table 1 above, in the examples, the desired effects (high visual transmittance, high blue light blocking ability) were shown.

Claims (9)

A plastic base material containing the compound represented by the formula (1).

In the formula, R ¹ represents a hydrogen atom, R ³ represents a methoxy group, and R ² represents a hydrogen atom . The plastic substrate according to claim 1 , further comprising a thiourethane resin. The plastic substrate according to claim 1 or 2 , wherein the light ray cut rate in the wavelength range of 380 to 500 nm is 29.0% or more. The plastic substrate according to any one of claims 1 to 3 , wherein the visual transmittance is 82.0% or more. A plastic lens comprising the plastic substrate according to any one of claims 1 to 4 . The plastic lens according to claim 5 , which is for spectacles. The plastic lens has a functional layer on at least one of the side surface of the object and the side surface of the eyeball.
The plastic lens according to claim 5 or 6 , wherein the light ray cut rate in the wavelength range of 380 to 500 nm is 20.0% or more. The plastic lens according to claim 7 , which has a visual transmittance of 95.5% or more. The plastic lens according to claim 7 or 8 , wherein the functional layer is one or more layers selected from the group consisting of a primer layer, a hard coat layer, an antireflection layer, and a water-repellent oil-repellent layer.