JPH08201735A - Plastic lens for sunglass - Google Patents

Abstract

PURPOSE: To provide such an acryl resin plastic lens for sunglasses that is light n weight and excellent in durability and can be easily worked by such as forming, cutting and grinding and that the contour of the objective can be more clearly recognized and problems of dazzling is improved without much decreasing the transmitted amt. of visible rays. CONSTITUTION: This lens consists of 100 pts.wt. of copolymer described below and 0.1-12 pts.wt. metal ions essentially comprising manganese ion and containing neodymium ion. The copolymer is an acryl resin having 0.5-60wt.% phosphate group or preferably such a copolymer obtd. by copolymn. of monomers expressed by PO(OH)n R3-n with monomers which are copolymerizable with those. In formula, R is CH2 =CXCOO(C2 H4 O)m <-> , X is hydrogen atom or methyl group, and (m) is an integer 0 to 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic lens for sunglasses, and more particularly to a plastic lens for sunglasses which has excellent visibility and antiglare property.

[0002]

2. Description of the Related Art Heretofore, many attempts have been made to introduce metal ions into a plastic material to impart an optical function thereto. As a carrier for this metal ion, optical properties such as transparency and mechanical properties such as strength are provided. Acrylic resins with excellent properties are widely used. As metal ions, manganese ions are dispersed in inorganic glass, and optical materials utilizing the light absorption characteristics of manganese ions, for example, sunglasses have been developed, but this inorganic glass optical material is heavy,
It also has the performance drawback of being brittle, and is
In addition to having many processing defects such as polishing, since the light rays in the entire visible light region are largely cut, the amount of light rays transmitted is reduced, the visibility is darkened, and it tends to be difficult to see. Especially, it is difficult to see the color of the signal of the road sign through sunglasses,
Alternatively, there is a problem such as an increase in risk due to a sudden decrease in the brightness of the field of view when a car is driven into a tunnel.

[0003]

It is known that manganese ion has a characteristic of absorbing a short wavelength region of visible light region, while neodymium ion has an absorption at a wavelength of about 580 nm. If both these ions are used together with manganese ion as the main component, the outline of the object can be more clearly identified without significantly reducing the light transmission amount in the entire visible light region, that is, without significantly reducing the brightness of the visual field. It has become clear that it is possible to improve the glare. The present invention has been made on the basis of such findings, the object thereof, it is possible to more clearly identify the contour of the object without significantly reducing the amount of transmission of visible light, and An object of the present invention is to provide a lens for sunglasses made of an acrylic resin, which has improved glare, excellent durability, is lightweight, and is easy to be processed in molding, cutting, polishing and the like.

[0004]

The plastic lens for sunglasses of the present invention comprises 100 parts by mass of an acrylic resin having a phosphate group content of 0.5 to 60% by mass, manganese ion (Mn ²⁺ ), and neodymium. It is characterized in that it is composed of ions (Nd ³⁺ ) and 0.1 to 12 parts by mass of metal ions whose main component is manganese ion. The mixing ratio of manganese ion and neodymium ion is preferably 1 to 12 in mass ratio, and the acrylic resin is composed of a monomer represented by the following chemical formula 2 and a monomer copolymerizable therewith. It is preferably a copolymer.

[0005]

Embedded image PO (OH) _n R _3-n [wherein R is CH ₂ ═CXCOO (C ₂ H ₄ O) _m — (X represents a hydrogen atom or a methyl group, and m is an integer of 0 to 5) , And n is 1 or 2. ]

Hereinafter, the present invention will be described in detail. The plastic lens for sunglasses of the present invention comprises a resin component which is an acrylic copolymer having a specific phosphoric acid group and an ionic metal component containing manganese ions as a main component and neodymium ions.

The phosphoric acid group contained in the resin component constituting the plastic lens for sunglasses of the present invention is a chemical compound containing a phosphoric acid group or in the molecule of the monomer constituting the resin component. May be present in the resin component in a state of being physically bonded. However, since the ionic metal component containing manganese ion as a main component, which will be described later, is dispersed in a state of being coordinated with the phosphoric acid group in the acrylic resin, in order to enhance the uniform dispersibility of the ionic metal component, the phosphoric acid group Is preferably uniformly dispersed and bonded in the resin.

As described above, the acrylic resin component constituting the plastic lens for sunglasses according to the present invention is preferably a polymer containing the monomer represented by the above chemical formula 2 as an essential component. As a monomer, (1) uniformly dissolve and mix with the monomer represented by Chemical formula 2, (2) have good radical copolymerizability with the monomer, and (3) be optically transparent. Any copolymer can be used without particular limitation as long as it can obtain a copolymer.

Specific examples of these copolymerizable monomers include:
Alkyl groups such as methyl acrylate, methyl methacrylate, ethyl acrylate, and ethyl methacrylate having a carbon number of 1 to 8 or lower alkyl acrylates, or alkyl groups such as ethoxyethyl acrylate and ethoxyethyl methacrylate through an ethylene oxide group. A monofunctional acrylate or monofunctional methacrylate such as a modified alkyl acrylate or a modified alkyl methacrylate in which an alkyl group is substituted with a glycidyl group such as a lower alkyl acrylate having a group, a lower alkyl methacrylate, glycidyl acrylate, or glycidyl methacrylate.

Ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 2 , 2-bis [4-acryloxyethoxyphenyl] propane, 2,2-bis [4- (methacryloxyethoxyphenyl] propane, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, Multifunctional acrylates such as pentaerythritol tetramethacrylate or multi-functional There is a methacrylate and the like.

R of the monomer represented by the chemical formula 2 is an acryloyloxy group (when X is a hydrogen atom) or a methacryloyloxy group (when X is a methyl group) to which an ethylene oxide group is bonded. Here, the repeating number m of the ethylene oxide group is an integer of 0 to 5. When the value of m exceeds 5, the hardness of the obtained copolymer is significantly reduced, and the practical use as a lens for sunglasses is lacking.

The number n of hydroxyl groups is 1 or 2,
The specific phosphoric acid group-containing monomer in which the value of n is 1, that is, the monomer in which the number of radically polymerizable ethylenically unsaturated bonds bonded to the phosphorus atom is 2, has crosslinkability, On the other hand, the specific phosphoric acid group-containing monomer having a value of n of 2 has the number of the ethylenically unsaturated bonds of 1 and has a large bondability with an ionic metal component such as manganese ion. . Therefore, in order to mold the plastic lens for sunglasses of the present invention by an injection molding method or an extrusion molding method which is a general molding method of a thermoplastic resin,
It is preferable to use a specific phosphoric acid group-containing monomer having a large mixing ratio of the monomer having a value of n of 2. On the other hand, in order to improve the binding property with manganese ions and obtain a plastic lens for sunglasses having a large surface hardness, the value of n is 1
It is preferable to mold the lens at the same time as the polymerization of the monomer by the cast polymerization method using the specific phosphoric acid group-containing monomer having a large mixing ratio of the monomer. However, the molding method is not limited to these.

As described above, the value of n and the mixing ratio thereof can be selected according to the performance of the plastic lens for sunglasses, the molding method and the purpose of use, but the value of n is 1.
Is preferably used in combination with a specific phosphoric acid group-containing monomer having a value of n of 2. In particular, these two kinds of specific phosphoric acid group-containing monomers are particularly preferable. It is more preferable to use the monomers in a ratio such that the monomers are substantially equimolar since the solubility of the metal compound containing a manganese compound described below as a main component in the mixed monomer is improved.

The acrylic resin, which is the resin component of the plastic lens for sunglasses of the present invention, may be, if necessary, other monomer copolymerizable with the above-mentioned acrylate monomer, such as acrylic acid or methacrylic acid. It may be a copolymer with a carboxylic acid such as an acid, an aromatic vinyl compound such as styrene, α-methylstyrene, a halogenated styrene, methoxystyrene or divinylbenzene.

The proportion of the phosphate group-bonded monomer used is at least 3% by mass, preferably 3 to 80% by mass, more preferably 30 to 30% by mass of the mixed monomer with the copolymerizable monomer.
It is 80 mass%. These acrylic group-bonded acrylic monomers are radically polymerizable monomers, so most of the monomers used with the copolymerizable monomers are polymerized and converted into copolymers. From the chemical formula 2, the amount of the phosphoric acid group is 0.5 to 60% by mass in the obtained acrylic copolymer. When the proportion of the monomer having the phosphate group bonded is less than 3% by mass,
It becomes difficult to disperse the required amount of metal ions containing manganese ions as a main component in the acrylic resin, and the plastic lens for sunglasses does not have the characteristics of sunglasses with excellent visibility clearness.

Next, the plastic lens for sunglasses of the present invention contains, as a constituent component, a mixed metal ion with a neodymium ion containing manganese ion as a main component.
Such a metal ion composed of manganese ion and neodymium ion is copolymerized by adding a mixed metal compound of a neodymium compound containing a manganese compound as a main component to the above acrylic resin or a monomer mixture thereof. As a result, it can be contained in the acrylic resin.

Here, "mainly containing manganese ions" means that the proportion of manganese ions in the metal ion components is 50% by mass or more, but manganese ions (Mn ²⁺ ) and neodymium ions are included. When indicating the mixing ratio of the (Nd ³⁺⁾ at a mass ratio (Mn ²⁺ / Nd ³⁺⁾ is preferably 1 to 19, more preferably 1 to 12, more preferably from 1 to 3. When the proportion of manganese ions is less than 50% by mass or Mn ²⁺ / Nd ³⁺ exceeds 19 and becomes large, the amount of visible light transmitted in the low wavelength region becomes too large, or the wavelength of 5
The balance of the amount of light transmission in both wavelength regions is impaired, such as the amount of transmission of wavelengths near 80 nm being too large, and the excellent feature of the present invention is that the brightness of the field of view is well balanced with the clarity and dazzling of the outline of the object. It becomes difficult to obtain the desired effect.
Further, the manganese compound and the neodymium compound used as a source of manganese ions and neodymium ions are mixed and used under conditions satisfying the ratio of the manganese ions. Further, as long as the object and effect of the present invention are not impaired, these metal compounds may contain a small amount of other metal compounds contained as impurities.

As the manganese compound constituting the metal compound, various compounds can be used, and one example thereof is manganese acetate, manganese acetylacetonate,
Ammonium manganese sulfate, manganese benzoate, manganese borate, manganese borofluoride, manganese bromide, manganese carbonate, manganese chloride, manganese 4-cyclohexylbutyrate, manganese 2-ethylhexylate, manganese formate, manganese naphthenate, manganese nitrate, manganese oxalate. Anhydrates and hydrates such as manganese oxide, manganese phosphate, manganese stearate, manganese sulfate, manganese phthalocyanine, manganese salicylate, manganese tartrate, and manganese tetrafluoroborate can be mentioned.

Examples of the neodymium compound include anhydrides such as neodymium acetate, neodymium chloride, neodymium nitrate, neodymium oxide, neodymium-2,4-pentanedionate, neodymium trifluoropentanedionate, neodymium fluoride and neodymium sulfate. A hydrate can be mentioned.

The use ratio of the ionic metal component containing manganese ions as the main component in the plastic lens for sunglasses of the present invention is 0.1 to 12 parts by mass as the amount of metal ion based on 100 parts by mass of the resin component, preferably 1 to
It is 10 parts by mass, more preferably 1 to 7 parts by mass. If the amount of this ionic metal component is less than 0.1 parts by mass, the absorption of the amount of transmitted light in the visible light region will be insufficient and the sunglasses function cannot be obtained. On the other hand, it is difficult to uniformly disperse a large amount of these metal ions in excess of 12 parts by mass in the phosphoric acid group-containing acrylic copolymer which is the resin component of the plastic lens for sunglasses of the present invention.

The plastic lens for sunglasses of the present invention comprises an acrylic copolymer obtained by radical polymerization of a mixed monomer essentially containing the phosphoric acid group-containing acrylic monomer shown in the above Chemical Formula 2, and the above-mentioned acrylic copolymer. Although consisting of an ionic metal component, the radical polymerization is not particularly limited, bulk polymerization using a normal radical polymerization initiator,
It can be carried out by a known polymerization method such as suspension polymerization, emulsion polymerization or solution polymerization. In these polymerization methods, prior to radical polymerization of a mixed monomer, a method of performing radical polymerization after adding and dissolving a metal compound serving as a supply source of the metal ion in the mixed monomer is a metal ion. It is preferable in that the dispersibility of is improved.

A method in which a phosphoric acid group-containing acrylic copolymer is first synthesized from the mixed monomer by a radical polymerization method, then the copolymer is heated and melted, and the metal compound is added and mixed, or The ionic metal component may be dispersed in the phosphoric acid group-containing acrylic copolymer resin component by a method of dissolving the copolymer in an organic solvent and adding and mixing the metal compound to the solution.

However, as a plastic lens for sunglasses of the present invention, from the viewpoint of practical performance, in addition to increasing the surface hardness, increasing the content of ionic metal components,
Moreover, from the viewpoint of improving the uniformity of the dispersion, the phosphoric acid group-containing acrylic monomer represented by Chemical formula 2 is preferably a mixture of n = 1 and 2. Therefore, the obtained phosphoric acid group-containing acrylic copolymer has a cross-linked structure and is difficult to use as a molding material for a molding method involving heating and melting. It is preferable to use a cast polymerization method in which the above forms are directly obtained.

[0024]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited thereto. In the following, "part" means "part by mass".

Example 1 31.5 parts of a phosphoric acid group-bonded acrylic monomer represented by the following chemical formula 3 and a phosphoric acid group-bonded acrylic monomer represented by the following chemical formula 4 18.5
Parts, 29 parts of methyl methacrylate, 20 parts of diethylene glycol dimethacrylate, and 1 part of α-methylstyrene were thoroughly mixed to prepare a mixed monomer. 30 parts of manganese benzoate tetrahydrate was added to this monomer (the content of manganese ion relative to 100 parts of the mixed monomer was 4.47).
Part) and 1.0 part neodymium acetate monohydrate (mixed monomer 1
Neodymium ion content is 0.425 with respect to 00 parts
Part) was added, and the mixture was stirred and mixed at 70 ° C. and sufficiently dissolved to obtain a monomer mixture in which manganese benzoate and neodymium acetate were dissolved.

[0026]

[CH ₂ = CCH ₃ COOC ₂ H ₄ O] ₂ PO (OH)

[0027]

CH ₂ = CCH ₃ COOC ₂ H ₄ OPO (OH) ₂

To the monomer mixture prepared as above, 2.0 parts of t-butylperoxyoctanoate was added and heated at 45 ° C. for 2 hours and then at 50 ° C. for 2 hours,
By heating from 50 ° C. to 60 ° C. in 6 hours, from 60 ° C. to 80 ° C. in 5 hours, from 80 ° C. to 100 ° C. in 3 hours, and heating at 100 ° C. for 2 hours to perform cast polymerization, A transparent plate-shaped plastic molded product having a thickness of 2 mm and made of an acrylic cross-linked copolymer containing manganese ions and neodymium ions was obtained.

The manganese ion amount (Mn amount) and the neodymium ion amount (Nd amount) in the obtained plastic molded product were 4.5% by mass and 0.43% by mass, respectively. The refractive index was 1.521 and the specific gravity was 1.353.
A spectrophotometer (Hitachi: U
400-450 nm and 555-605 nm from the spectral transmittance curve in the visible light region (wavelength: 400-700 nm) measured using a -4000 type self-recording spectrophotometer)
The transmittances of were 0.22% and 60.3%.

Next, when the object was observed through the same molded article, the glare and sharpness (the extent to which the contour of the object can be clearly discerned) were visually evaluated by the following method, and 1) glare It was confirmed that the sharpness was reduced, and 2) the sharpness of the lamp outline was clearly improved. The results of these measurements are summarized in Table 1.

[Visual test of glare and clarity] JIS C
Whether the narrow band emission type three-wavelength emission type EX-N (27W) fluorescent lamp specified in 7601 is directly viewed through the molded article from a distance of 50 cm, and 1) whether the degree of glare is improved, And 2) Whether or not the sharpness of the contour of the lamp was improved was evaluated according to the following criteria. Evaluation criteria ○: There is an improvement effect. Δ: Both are difficult to judge. X: No improvement is recognized.

Example 2 44.1 parts of the acrylic monomer to which the phosphoric acid group represented by the above Chemical Formula 3 is bonded is added to the above Chemical Formula 4
Acrylic monomer with a phosphate group
In 5.9 parts, 23.5 parts of manganese benzoate tetrahydrate (the content of manganese ion is 3.50 parts with respect to 100 parts of the mixed monomer) and 3.5 parts of neodymium acetate monohydrate ( A transparent plate having a thickness of 2 mm was cast-polymerized in the same manner as in Example 1 except that the content of neodymium ion relative to 100 parts of the mixed monomer was changed to 1.49 parts and diethylene glycol dimethacrylate was excluded. A plastic molded product was obtained.

The amount of manganese ions, the amount of neodymium ions in the obtained plastic molded product, and the refractive index of the molded product,
Specific gravity, further wavelengths 400-450 nm and 555-60
The light transmittance at 5 nm, the glare and the sharpness were measured in the same manner as in Example 1, and the results are shown in Table 1.

[Example 3] Manganese benzoate tetrahydrate was changed to 20 parts and neodymium acetate monohydrate was changed to 7 parts, and "Biosorb 583" (manufactured by Kyodo Yakuhin Co., Ltd.) was newly used as an ultraviolet absorber. ) Was used in the same manner as in Example 1 to obtain a plate-shaped transparent plastic molded product having a thickness of 2 mm.

The amount of manganese ions, the amount of neodymium ions in the obtained plastic molded product, and the refractive index of the molded product,
Specific gravity, further wavelengths 400-450 nm and 555-60
The light transmittance at 5 nm, the glare and the sharpness were measured in the same manner as in Example 1, and the results are shown in Table 1.

Example 4 Manganese benzoate tetrahydrate was changed to 4 parts and neodymium acetate monohydrate was changed to 1 part, and a plate-like transparent plastic having a thickness of 2 mm was prepared in the same manner as in Example 1. A molded product was obtained.

The amount of manganese ions, the amount of neodymium ions in the obtained plastic molded product, and the refractive index of the molded product,
Specific gravity, further wavelengths 400-450 nm and 555-60
The light transmittance at 5 nm, the glare and the sharpness were measured in the same manner as in Example 1, and the results are shown in Table 1.

Example 5 20 parts of diethylene glycol dimethacrylate and 29 parts of methyl methacrylate were mixed in 2 parts.
-Hydroxyethyl methacrylate was changed to 49 parts, and manganese benzoate tetrahydrate was changed to 35 parts and neodymium acetate monohydrate was changed to 11 parts. A plastic molded product was obtained.

The amount of manganese ions, the amount of neodymium ions in the obtained plastic molded product, and the refractive index of the molded product,
Specific gravity, further wavelengths 400-450 nm and 555-60
The light transmittance at 5 nm, the glare and the sharpness were measured in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 1 6.3 parts of the phosphoric acid group-bonded acrylic monomer represented by Chemical Formula 3 above and the phosphoric acid group-bonded acrylic monomer represented by Chemical Formula 4 above 3.7 parts and 20 parts of diethylene glycol glycol dimethacrylate,
29 parts of methyl methacrylate, 40 parts of 2-hydroxyethyl methacrylate, and 1 part of α-methylstyrene were sufficiently mixed to prepare a mixed monomer. In this monomer,
A monomer mixture was prepared by adding and mixing 5 parts of manganese benzoate tetrahydrate. This monomer mixture was cast-polymerized in the same manner as in Example 1 to obtain a transparent plate-shaped plastic molded product having a thickness of 2 mm.

The amount of manganese ions in the obtained plastic molded product, the refractive index and the specific gravity of the molded product, and the wavelength of 4
The light transmittances at 00 to 450 nm and 555 to 605 nm, and the glare and sharpness were measured in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 2 To the same mixed monomer as in Example 1, 10 parts of neodymium acetate monohydrate and 0.2 part of an ultraviolet absorber "Biosorb 583" (manufactured by Kyodo Chemical Co., Ltd.) were added. The resulting mixture was thoroughly dissolved and mixed to prepare a monomer mixture. To this monomer mixture was added t-butyl peroxypivalate 2.0.
Parts were added and cast polymerization was carried out under the same temperature and time conditions as in Example 1 to obtain a transparent plate-shaped plastic molded product having a thickness of 2 mm.

The amount of neodymium ions in the obtained plastic molding, the refractive index and the specific gravity of the molding, and the wavelength of 4
The light transmittances at 00 to 450 nm and 555 to 605 nm, and the glare and sharpness were measured in the same manner as in Example 1, and the results are shown in Table 1.

[0044]

As described above, in the plastic lens for sunglasses of the present invention, the polymer composed of the phosphoric acid group-bonded acrylic monomer is used as the resin component, and the manganese ion is the main component in the resin component. Since the mixed ions with the neodymium ion are dispersed, it can efficiently absorb the short wavelength region of visible light and light in the wavelength range of 555 to 605 nm, and is based on the reduction of scattered light in the short wavelength region of visible light. It also achieves an improvement in sharpness and an improvement in glare at the same time, has a low specific gravity, and is easy to process such as molding, cutting and polishing, and has excellent productivity. Because of these characteristics, it can be preferably used for goggles as well as sunglasses.

[0045]

[Table 1]

Claims (3)

[Claims] 1. A manganese ion as a main component comprising 100 parts by mass of an acrylic resin having a phosphate group content of 0.5 to 60% by mass, manganese ion (Mn ²⁺ ) and neodymium ion (Nd ³⁺ ). A plastic lens for sunglasses, which comprises 0.1 to 12 parts by mass of metal ions. 2. The sunglasses according to claim 1, wherein the mixing ratio (Mn ²⁺ / Nd ³⁺ ) of manganese ion (Mn ²⁺ ) and neodymium ion (Nd ³⁺ ) is 1 to 12 in mass ratio. Plastic lens. 3. The plastic lens for sunglasses according to claim 1, wherein the acrylic resin is a copolymer of a monomer represented by the following chemical formula 1 and a monomer copolymerizable therewith. Embedded image PO (OH) _n R _3-n [wherein R is CH ₂ ═CXCOO (C ₂ H ₄ O) _m − (X represents a hydrogen atom or a methyl group, and m is an integer of 0 to 5) , And n is 1 or 2. ]