JPS59161416A - Resin having high refractive index and its preparation - Google Patents

Abstract

PURPOSE:To obtain a resin having high refractive index, useful as plastic lens, etc., having improved transparency, by copolymerizing a styrene (derivative) with a metal salt of (meth)acrylic acid, a metal salt of an aromatic carboxylic acid, and (meth)acrylic acid. CONSTITUTION:A monomer shown by the formula I (X is H, chlorine, bromine, iodine, methoxy, amino, nitro, phenyl or phenoxy; a is 1 or 2) is copolymerized with a monomer shown by the formula II (M is metal; R1 is H, or methyl; m is oxidation number of metal), a monomer shown by the formula (R2COO)nM(R2 is benzene nucleus-containing group; n is as shown for m), and a monomer shown by the formula III, to give the desired resin consisting of a copolymer containing repeating units shown by the formula IV-formula VII. An amount of the methacrylic acid shown by the formula III is preferably 1.05-2 times the amount wherein number of moles of total carboxylic acid is equimolar to number of moles of metal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a high refractive index resin with excellent transparency and particularly suitable for use in glass lenses, and a method for producing the same.

[Prior art]

Plastic lenses have come to be widely used as optical components, taking advantage of the advantages of being lightweight, easy to mold, and highly safe. There are already resins for plastic lenses such as polymethyl methacrylate and polydiethylene glycol bisallyl carbonate, which are also used for eyeglass lenses, but these resins have a low refractive index (nD# 1.49 to 1.50). ,
When used as a camera lens, it is necessary to reduce the radius of curvature of the lens, resulting in larger aberrations than inorganic glass, making it difficult to increase the aperture and magnification. Polycarbonate (np=1.58) and polystyrene (nD:
1.59), but it is still small compared to the refractive index of glass. Furthermore, these thermoplastic resins tend to exhibit birefringence due to orientational strain during injection molding.
Variations in optical properties pose a problem.

Therefore, its use is limited to safety glasses, sunglasses, etc. Recently, the refractive index of resin has been increased,
No proposal was made to produce a resin with a high refractive index. For example, JP-A-57-2312, JP-A-57-54901, JP-A-57-28117, JP-A-56-1662j4 and JP-A-5
There are resins made from brominated compounds described in each publication No. 7-2-8118. However, since these resins are generally susceptible to desorption of bromine, there is a problem in that plastic lenses formed by injecting the monomer into a lens mold and then thermosetting them are colored yellow. In order to avoid this problem, a colorless and transparent plastic lens can be obtained by lowering the curing temperature, but in this case,
Since the curing time must be increased, there is a problem in mass production. Similarly, there are also problems in terms of light resistance, such as yellowing during use due to desorption of bromine.

On the other hand, one of the effective methods to increase the refractive index of plastics is to introduce heavy metals into them.
It is one. JP-A-56-147101 and JP-A-57-5705 as technology related to metal-containing plastic lens materials.
No. 57-28115, No. 57-28115, etc. However, monomers with covalently bonded metals or metal salts of carboxylic acids containing double bonds generally have poor solubility in styrene or styrene derivatives. Further, even if only one of these metal salts of carboxylic acid is used and copolymerized with a reactive monomer such as chlorostyrene, the transparency of the resin is poor and there is still a problem as a plastic lens material. Also, if you want to maintain a high level of resin transparency,
Since the amount of metal contained in the resin must be extremely small, it is not possible to sufficiently increase the refractive index of the plastic.

Therefore, the present inventors have conducted extensive research on resins that contain a sufficient amount of metal in the polymer to exhibit a sufficient effect of increasing the refractive index of the resin, and that also have a high degree of optical transparency. As a result, in addition to styrene and/or styrene derivatives and metal salts of acrylic acid and/or metal salts of methacrylic acid, a new combination of metal salts of carboxylic acids having a group containing a benzene nucleus and acrylic acid and/or methacrylic acid was added. The inventors have discovered that a resin with a high refractive index and excellent transparency can be obtained by using a copolymer, and have arrived at the present invention.

[Purpose of the invention]

An object of the present invention is to provide a metal-containing resin for plastic lenses that maintains a high degree of optical transparency and has a high refractive index, specifically a refractive index of nD=1.60 or more, and a method for producing the same. .

[Summary of the invention]

To summarize the present invention, the first invention of the present invention relates to a high refractive index resin, which has the following general formulas [1] to [4]: [wherein X is hydrogen, chlorine, bromine, iodine, methoxy group, amino group, nitro group, phenyl group or phenoxy group, a represents 1 or 2] 1 [In the formula, M represents a metal element, R1 represents hydrogen or a methyl group, and R represents a benzene nucleus. represents the containing group, n represents the oxidation number of the metal] 1 +cu, -c arrow ... [5] 0
0H [In the formula, R1 has the same meaning as above] 1 basket + 0-OH Tomimo-4) Horse [In the formula, R1 and M have the same meaning as above, and m represents the oxidation number of the metal] It is characterized by being a copolymer containing each repeating unit.

The second invention of the present invention is an invention of a method for producing a high refractive index resin, which has the following general formula [l]: [wherein X is hydrogen, chlorine, bromine, iodine, methoxy group, amino group, Represents a nitro group, a phenyl group or a haphenoxy group, and a is a monomer ore 2
] and the general formula 1: 1 [in the formula, M represents a metal element, R1 represents hydrogen or a methyl group, and m represents the oxidation number of the metal] and the general formula Otori: (R,000)nM ・...(I
I) [In the formula, M has the same meaning as above), R1 represents a group containing a benzene nucleus, and n represents the oxidation number of the metal] and general formula ■: 1 [In the formula, R1 has the same meaning as above] ] is characterized by copolymerizing monomers whose main components are

In the present invention, since the metal salt of (meth)acrylic acid hardly dissolves in the styrene and/or styrene derivative, saturated or unsaturated carbonization containing benzene nuclei is newly added to the monomer mixture. The solubility could be increased by adding a metal salt of a carboxylic acid having a hydrogen group.

Furthermore, it has been found that metal salts of carboxylic acids containing benzene nuclei have the effect of increasing the refractive index of transparent resins. However, when producing plastic lenses by heating and curing these monomers, the transparency cannot be said to be sufficient. That is, when a metal salt of (meth)acrylic acid and a carboxylic acid containing a benzene nucleus is copolymerized with a reactive monomer, the metal salt of a carboxylic acid (m carboxylic acid metal salt to t moles of valent metal)
In this case, the presence of fine particles in the resin causes transmitted light to be scattered, resulting in poor transparency.

They discovered that this problem could be solved by increasing the number of moles of carboxylic acid that ionically bonds with the metal to more than an equimolar number, and decided to add (meth)acrylic acid.

However, if the amount of (meth)acrylic acid is too large, the resin will become cloudy. The amount of (meth)acrylic acid varies depending on the metal and the type of carboxylic acid containing a benzene ring, but is 1.05 to zO times the amount at which the number of moles of total carboxylic acid is equivalent to the number of moles of metal. It is preferable to mix them so that the ratio is as follows.

Examples of metal salts of carboxylic acids having a group containing a benzene nucleus in the present invention include metal salts of carboxylic acids represented by the following general formula.

Engineering a H H0OOH R@000 H 00H! [In the above formulas v to (i), Y represents hydrogen, chlorine, bromine, iodine, methoxy group, amino group, nitro group, or cyano group, and R3
represents an alkyl group, an alkenyl group, an aryl group, an aralkyl group, a cyclohexyl group, - and a horse represent hydrogen, a methyl group, chlorine, bromine or a cyano group, - represents a phenyl group,
Represents a benzyl group or a 7enethyl group. Further, a represents 1 or 2, ) represents 0 to 5, and d represents 1 to 5. ] Examples of formula V include benzoic acid, phenylacetic acid, hydrocinnamic acid, 4-phenylbutyric acid, 5-phenylvaleric acid H1O2mtl) -chlorophenylacetic acid fL 2-phenylpropionic acid, 2
-phenyl-n-butyric acid, 3-phenyl-n-butyric acid, etc. Examples of formula (1) include phenoxyacetic acid, 5-phenoxypropionic acid, 0sP-chlorophenoxyacetic acid, and the like. Examples of formula ■ are monoethyl phthalate, monobenzyl phthalate, monoallyl phthalate, monovinyl phthalate,
Examples include monocyclohexyl phthalate, monomethyl terephthalate, monoethyl terephthalate, and monocyclohexyl terephthalate. Examples of formula (2) include cinnamic acid, α-methylcinnamic acid, β-methylcinnamic acid, α-cyanocinnamic acid, and the like. Examples of formula ■ are monophenyl maleate,
Examples include monobenzyl maleate. Examples of formula X include monophenyl fumarate, monobenzyl fumarate, and the like.

Examples of Formula I include monophenyl itaconate, monobenzyl itaconate, and the like. An example of such a compound is 3-benzoyl acrylic acid. Examples of formula (1) include diphenylacetic acid (bis-(4-methoxyphenyl)acetic acid).These compounds can be used alone or in combination of two or more.

In the present invention, when producing a metal salt of (meth)acrylic acid and a carboxylic acid having a group containing a benzene nucleus, known methods can be used. That is, after dissolving carboxylic acid in a polar solvent such as water or alcohols or a non-polar solvent such as benzene or toluene, metal oxides, hydroxides, chlorides, nitrates, acetates, carbonates, etc. are added to the solution. The reaction is carried out by slowly adding the metal compound as a solid, in the form of a solution or slurry, at room temperature or in a heated state while stirring. Metal salts of carboxylic acids are formed as precipitates or dissolved in solvents. The precipitated product is filtered and dried under vacuum with heating.

A metal salt of a carboxylic acid dissolved in a solvent can be obtained by removing the solvent by distillation under reduced pressure.

The metal compounds used here include Pb and Ba.

Br, Zn, 8n, 8b, Oa, La,
Ti, Zr.

Compounds such as Ta, Th, Msu, Tt, and G6 can be used. The metal salts of carboxylic acids prepared using these metal compounds may be used alone or in combination of two or more.

Examples of the polymerization initiator used when thermally curing the obtained monomer composition include benzoyl peroxide, lauroyl peroxide, diisopropyl peroxydicarbonate, similistil peroxydicarbonate, and azobisisobutyronitrile. Conventional radical initiators can be used. In addition, when curing with ultraviolet rays, polymerization initiators such as penzoin isoglobyl ether, benzoin ethyl ether, benzoin isobutyl ether, a-allylbenzoin, α-methylpentyne, benzophenone, benzyl 2-ethyl anthraquinone, etc. can be used. These ultraviolet curing type polymerization initiators can not only be used alone, but also thermosetting type polymerization initiators can be used in combination.

Furthermore, the production of the resin for plastic lenses according to the present invention includes:
A mixture of the above monomer composition and a polymerization initiator is poured into a mold (glass or metal mold) and a gasket (K), and heated or irradiated with ultraviolet rays. This is done by curing. Of course, it is also possible to adopt a method of curing by irradiating with radiation without using an initiator.

[Embodiments of the invention]

EXAMPLES In order to explain the present invention more specifically, Examples and Comparative Examples will be described below, but the present invention is not limited to these Examples. The physical properties of the high refractive index plastic lens resins obtained in Examples and Comparative Examples were measured using the following test methods.

(1) Refractive index (nD) and Atsube number The refractive index and Atsube number at 25° C. were measured using Atsube's refractometer. α-monobromonaphthalin was used as the contact liquid.

(2) Light transmittance was measured using a haze meter (manufactured by Suga Test Instruments Co., Ltd.) on a 2-inch thick test piece.

Example 1 Mixed chlorostyrene (ortho/hara: 60/40) 47
(parts by weight, same hereinafter), 13 parts of lead methacrylate, 33 parts of lead hydrocinnamate, and 7 parts of methacrylic acid were mixed at 50°C to obtain a transparent and clear monomer composition. Next, to this monomer composition, as a polymerization initiator, cimilistyl peroxydicarbonate (Perloyl MSP manufactured by NOF Corporation) was added.
．． 25 parts were added and mixed and poured into a casting mold consisting of two glass molds and a gasket. After curing by heating at 55° C. for 4 hours and 90° C. for 3 hours, the transparent polymer lens was taken out. The obtained polymer lens had optical properties (1dn)) = 1.615 and an Abbé number of 31.7, and was sufficiently suitable for practical use as a plastic lens. Furthermore, the light transmittance of a polymer made using this monomer composition was 90%.

Example 2 30 parts of styrene, 50 parts of lead methacrylate, 1 part of lead cinnamate
0 parts of methacrylic acid and 10 parts of methacrylic acid were mixed together at 60'C to obtain a transparent and clear monomer composition. This monomer composition contains diimpropyl peroxycarbonate I as a polymerization initiator,
Two parts were added and mixed, and a plastic lens was cast and molded in the same manner as in Example 1. The obtained polymer lens was transparent, and its optical properties were nD=1.627 and Abbe's number 274. In addition, the light transmittance of this polymer is 88
%Met.

Example 3 Mixed chlorostyrene (ortho/hough = 60/40) 50
15 parts of barium acrylate, 20 parts of lead methacrylate, 10 parts of barium salt of monobenzyl maleate, and 5 parts of acrylic acid were mixed at 50° C. to obtain a transparent and clear monomer composition. 125 parts of cimilistyl peroxydicarbonate as a polymerization initiator was added and mixed to this monomer composition, and a plastic lens was cast-molded in the same manner as in Example 1. The obtained polymer lens was transparent, and its optical properties were nD==1.613 and Abbe's number 296.

Moreover, the light transmittance of this polymer was 90%.

Example 4 Mixed chlorostyrene (ortho/hara=ba/40) 50
5 parts of lanthanum methacrylate, 20 parts of lead methacrylate, 20 parts of lead salt of monoethyl phthalate, and 5 parts of acrylic acid were mixed at 60° C. to obtain a transparent and clear monomer composition. 125 parts of cimilistyl peroxydicarbonate as a polymerization initiator was added and mixed to this monomer composition, and a plastic lens was cast-molded in the same manner as in Example 1. The obtained polymer lens is transparent and its optical properties are np
= 1.622 Atsbe's number was 3α5. Moreover, the light transmittance of this polymer was 88%.

Example 5 Mixed chlorostyrene/(ortho/para=60/40) 47
24 parts of lead methacrylate, 24 parts of 3-phenoxypropionic acid, and 5 parts of methacrylic acid were mixed at 50°C to obtain a transparent and clear monomer composition. Similystyl peroxydicarbonate 125 was added to this monomer composition as a polymerization initiator.
A plastic lens was cast and molded in the same manner as in Example 1. The obtained polymer lens was transparent, and its optical properties were np=1.614 and Abbe's number 52.0. Also, the light transmission type of this polymer is 89
%Met.

Example 6 47 parts of promostyrene, 25 parts of lead methacrylate, 16 parts of lead salt of monobenzyl fumarate, and 14 parts of methacrylic acid were added in 5 parts.
The mixture was mixed at 0°C to obtain a transparent and clear monomer composition. 12 parts of diimprovil diperoxycarbonate as a polymerization initiator was added and mixed to this monomer composition, and a plastic lens was cast-molded in the same manner as in Example 1.

The obtained polymer t/lens was transparent and its optical properties were np: 1.415 and Atsubbe number 31.2.

The light transmittance of this polymer was 89%.

Example 7 Mixed chlorostyrene (ortho/hara=60/4G) 47
23 parts of lead methacrylate, 15 parts of lead salt of monobenzyl itaconate, and 15 parts of methacrylic acid were mixed at 50° C. to obtain a transparent and clear monomer composition. To this composition, 0.5 part of similistil peroxydicarbonate was added and mixed as a polymerization initiator. A plastic lens was obtained in the same manner as in Example 1. The obtained polymer lens was transparent, and its optical properties were nD=1.608 and Abbé number 32.1. The light transmittance of this polymer was 90%.

Example 8 Mixed chlorostyrene (ortho/hara=bo/40) 47
23 parts of lead methacrylate, 16 parts of lead 5-benzoyl acrylate, and 14 parts of methacrylic acid were mixed at 50°C to obtain a transparent and quenchable monomer composition. This monomer composition contains 0.00% of cimilistyl peroxydicarbonate as a polymerization initiator.
25 parts were added and mixed, and a plastic lens was cast and molded in the same manner as in Example 1. The obtained polymer lens was transparent, and its optical properties were nD: t 609 and Abbé number 32.0. The light transmittance of the polymer was 90%.

Example 9 Mixed chlorostyrene/(ortho/rose=60/40) 47
24 parts of lead methacrylate, 20 parts of lead salt of bis=(4-methoxyphenyl)acetic acid, and 9 parts of methacrylic acid were mixed at 60°C to obtain a transparent and clear monomer composition. To this monomer composition were added and mixed 25 parts of Dimyristylbaroxydicarbonate Q as a polymerization initiator, and a plastic lens was cast in the same manner as in Example 1.

The obtained polymer lens was transparent, and its optical properties were nD" 1.618 and Abbe's number 31.5.

Moreover, the light transmittance of this polymer was 89%.

Example 10 Mixed chlorostyrene (ortho/rose = 60740) 4
7 parts of lead methacrylate, 50 parts of parachlorophenylacetic acid, and 7 parts of methacrylic acid were mixed at 50°C to obtain a transparent and clear monomer composition. Next, this monomer composition was added with 0 cimilistyl peroxydicarbonate as a polymerization initiator.
．． 25 parts were added and mixed, and a plastic lens was cast and molded in the same manner as in Example 1. The obtained polymer lens was transparent, and its optical properties were np=t 616 and Atsube's number 31.5, and it was sufficiently suitable for practical use as a plastic lens.

Moreover, the light transmittance of this polymer was 89%.

Comparative Example 1 Mixed chlorostyrene (ortho/rose = 60740) 60
Although 40 parts of lead methacrylate were mixed at 60° C., the lead methacrylate was not completely dissolved and a portion remained as a precipitate. Therefore, the precipitate was removed by subjecting this monomer composition to heat treatment. Thereafter, 25 parts of dimyristyl peroxydicarbonate (L) was added as a polymerization initiator to 100 parts of the monomer composition, and the mixture was poured into a casting mold in the same manner as in Example 1. ℃4 hours, 100℃
After heating and curing for 3 hours, polymerization occurred and the lens was taken out. The obtained polymerized lens was white and translucent and could not be used as a plastic lens.

Comparative Example 2 Mixed chlorostyrene (ortho/hara=6 Q/40)
60 parts, lead methacrylate 2o parts, lead hydrocinnamate 20 parts
The two parts were mixed at 50°C to obtain a monomer composition. This monomer composition did not produce grains, but was a slightly glossy solution.

125 parts of dilysyl peroxydicarbonate as a polymerization initiator was added and mixed to 100 parts of this monomer composition, and a plastic lens was cast-molded in the same manner as in Comparative Example 1. The resulting polymer lens was slightly cloudy;
This was not enough for a plastic lens. The light transmittance of this polymer was 60%.

〔Effect of the invention〕

As described above, 1. Copolymerizing styrene and/or a styrene derivative with a metal salt of acrylic acid and/or a metal salt of methacrylic acid with a metal salt of a carboxylic acid containing a benzene nucleus and acrylic acid and/or methacrylic acid. This has made it possible to manufacture high refractive index plastic lenses with a high degree of optical transparency. Further, since the resin of the present invention is a three-dimensional crosslinked polymer formed by ionic bonding of metals, it not only has good scratch resistance but also has various properties such as being able to be ground with a diamond grindstone.

Patent applicant: Hitachi, Ltd. Agent
Hiroshi Nakamoto

Claims (1)

[Claims] 1. The following general formulas [1] to [4]: [wherein X represents hydrogen, chlorine, bromine, iodine, methoxy group, amino group, nitro group, phenyl group or phenoxy group, a represents 1 or 2] 1 Tsuta [In the formula, M represents a metal element, R1 represents hydrogen or a methyl group, "2 represents a group containing a benzene nucleus, and n represents the oxidation number of the metal] I 00H [In the formula, R1 has the same meaning as above] 藝+c-am, ± 1 (m-1) [In the formula, R1 and M have the same meaning as above, and m represents the oxidation number of the metal] A high refractive index resin characterized by being a copolymer containing repeating units of group, phenyl group or phenoxy group, and a represents 1 or 2] and general formula 11 = M+o -o -'a-cH,),
・(1) Peng [in the formula, M represents a metal element, R1 represents hydrogen or a methyl group, and m represents the oxidation number of the metal] and the general formula H: (R, coo)nM-...(IIl) [In the formula, y has the same meaning as above], s represents a group containing a benzene nucleus, and n represents the oxidation number of the metal] and the general formula ■: HO-1-0 OH!... (IV
)■ A method for producing a high refractive index resin, which comprises copolymerizing a monomer containing as a main component [in the formula, R violet has the same meaning as above].