JPH02133415A - Production of high refractive index plastic lens - Google Patents

Abstract

PURPOSE:To improve the moldability by copolymerizing a specific di(meth) acrylate with a radical-polymerizable compd. in the presence of a polymn. initiator and a polymn. regulator. CONSTITUTION:1-99wt.% di(meth)acrylate contg. an arom. ring (e.g., 1,4- dimethacryloxybenzene) is copolymerized with 99-1wt.% compd. radical copolymerizable with said di(meth)acrylate (e.g., styrene) in the presence of 0.1-10wt.% (based on the total components) polymn. initiator, org. peroxide with a decomposition temp. to obtain a 10hr half life of 50-120 deg.C, and 0.1-20wt.% (based on the total components) polymn. regulator, 2,4-diphenyl-4-methyl-1- pentene of the formula, at 50-140 deg.C for 2-4hr.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a straw-dust refractive index plastic lens with excellent moldability.

(Prior Art) In the past, many studies and proposals have been made on plastic lenses to replace inorganic glass lenses, but compared to inorganic glasses, the refractive index of a polymer such as diethylene glycol bisallyl carbonate is 1.49. low. In recent years, there have been proposals to further improve the refractive index of plastic lenses and to manufacture high refractive index plastic lenses. For example, Japanese Patent Publication No. 55
-13747 and %Kaisei No. 54-77686.

In order to obtain a high refractive index resin, it is necessary to use a high refractive index compound, and generally diacrylates and dimethacrylates having all aromatic rings, and 1 having aromatic
Functional vinyl compounds, acrylates and A-tacrylic V
-) has been proposed as an appendage.

(Problems to be Solved by the Invention) However, although the refractive index of the above-mentioned high refractive index resins has improved to 1.58 to 1.61, diacrylates and dimethacrylates having aromatic Because it is the main component, the curing speed of the resin is fast and the curing shrinkage rate is large. A compound having an aromatic ring has a problem in that it has poor sealing force with the mold, and in particular, the surface condition of the cast heavy body becomes poor, and the surface becomes uneven due to shrinkage during polymerization.

To solve this problem, a method has been proposed in which acrylates or methacrylates having an alcoholic hydroxyl group are added to the product compound in order to improve the adhesion with the mold (
For example, Japanese Patent Application Laid-Open No. 58-76410) is not effective in controlling the curing shrinkage rate, and therefore, the above-mentioned cast polymerization is generally carried out after curing at a relatively low temperature for a long time, followed by a short period of time. Methods are used to suppress the rapid curing shrinkage of M resin, such as post-curing at high temperatures, but even then, unevenness occurs on the surface of the cast polymer due to shrinkage, resulting in loss of commercial value as a lens. In addition, the polymerization cycle was long, so it was not possible to quickly respond to the need for ammonium water for two customers.

(Means for Solving the Problems) The present inventors used an organic filtrate as a polymerization initiator to obtain a half-life of J41110 hours when producing a high refractive index plastic lens. By using an oxide and further adding a compound of the following structural formula as a polymerization modifier, plastic nons with high refractive index and excellent moldability can be obtained without deterioration of other properties. This discovery led to the present invention.

H3 Diacrylate or dimethacrylate having an aromatic ring used in the present invention (AI is a general term including its nuclear halogen substituted products, and known ones can be used without particular restriction. Preferred use is 8 Typical examples include:
For example, 1,4-dimethacryloxybenzene, 1,6-diacryloxybenzene, 2,2-his(4-methacryloxy-2-enyl)propane, 2,2-bis(4-acryloxyethoxyphenyl)propane, Bis(4-methacryloquine phenylnesulfone, bis(4-acryloxyethoxyphenyl)sulfone) is substituted with nuclear halogen (excluding fluorine) in the diacrylate and dimethacrylate mentioned above in the present invention. In the case of using a plastic lens, it is possible to obtain a glass lens with flame retardancy and a high refractive index.As such a nuclear halogen substituted substance, for example, 1,4-diacrylate-2,6,5 ,6
-Tetrafrombenzene, dimethacrylate (4-
chlorophenyl)methane, tetrabromophthalic acid-di(
2-acryloxyethyl), 2.2bis(4-acryloxyethyl-3,5-dibromphenyl)propane,
Bis(4-methacryloxyethoxy-5-bromo2enyl)sulfone, bis(4-methacryloki7ethyne-6
, 5-dichlorophenyl) sulfone, bis(4-methacrylates "roboquine-3,5-dichlorophenylsulfone", etc.) are used.

In addition, a compound capable of radical polymerization BJ (Bl
Preferred examples include vinyl, methacrylate and azirylate, and 4el, whose homopolymer has a refractive index of 1.
．． Those of 55 or more are preferred. For example, styrene derivatives such as styrene, vinyltoluene, metkinstyrene;
Nuclear halogen-substituted styrenes such as chlorstyrene, bromstyrene, iodostyrene, dichlorostyrene; 2-enyl methacrylate, chlorphenyl methacrylate,
Acrylates and methacrylates such as dibromo phenyl acrylate, metquin phenyl acrylate, benzyl methacrylate, bromobenzyl methacrylate, dibromobenzyl acrylate, tribromobenzyl methacrylate, pentabromo acrylate, trichrome methacrylate; other α-naphthyl methacrylate, β-naphthyl These include methacrylates and mixtures thereof.

Above, aroma f! The blending ratio of the compound (A) whose main component is diacrylate or dimethacrylate having J and the radically polymerizable compound tBJ is 1-
It is most commonly used in amounts of 99X, preferably in the range of 5 to 951%. That is, if less lightning is applied to B, the mechanical properties of the copolymer will deteriorate. Reverse KA
If the amount of the compound used is too large, the crosslinking density becomes too high, which tends to cause the copolymer to become discolored and brittle. Therefore, it is preferable to determine the blending ratio of compound A and compound B in advance depending on the physical properties required for the copolymer.

In the present invention, a high refractive index plastic lens with excellent bottom shape is produced by polymerizing a mixture of the above compounds in the presence of a radical polymerization initiator.

As a result of intensive study as the above radical polymerization initiator, 10
The decomposition temperature to obtain the full half-life is 50℃~120℃
Organic peroxide and polymerization! ! It has been found that very good results are obtained when 2,4-diphenyl-4-methyl-1-pentene is used as the shaving. Organic peroxide whose decomposition temperature is below 50℃? ! If I is used, the crosslinking density of the polymer will be low and the heat resistance will be low, and if an organic peroxide with a temperature of 120° C. or higher is used, the polymer will tend to be colored.

Examples of the organic peroxide include ketone peroxides such as cyclohexanone peroxide and methyl ether ketone peroxide; Peroxyketals such as 1,3゜5-trimethane chlorhexanone, 1,1bis(tert-butylferoxy)cyclohexane, etc. - dikbarber oxide, 2,5-dimethyl-2,5-di(tert-butyl) Dialkyl peroxides such as ferroquine) hexanone, shea/ruver oxides such as acetyl peroxide, lauroyl peroxide, decanoyl peroxide, benzoyl peroxide - tertiary terpterper i quinpivalate, tertiary
Examples include peroxide diesters such as butyl peroxyneodecanoate, tert-hexyl peroxy bivalate, and tert-butyl peroxy-72-ethylhexanoate.

Although it cannot be definitively determined depending on the amount of radical polymerization initiator, the polymerization type 2M conditions, and the type and amount of copolymerization components, it is best to use it in the range of 0.1 to 10% by weight based on the total compound. suitable. Further, the amount of 2,4-diphenyl-4-methyl-1-pentene added is preferably in the range of 0.1 to 20% by weight based on the total compound.

The polymerization method in the present invention is not particularly limited, and any known polymerization method may be employed. Cast polymerization can be cited as a typical polymerization method.

For example, a radical polymerization initiator and 2,4
The mixture of copolymerized compounds containing -diphenyl-4-methyl-1-pentene is injected, cured in a dryer, and then taken out. Among polymerization conditions, temperature in particular affects the properties and polymerization cycle of high refractive index plastic lenses.

In the present invention, it is preferable to terminate the polymerization at 50°C to 140°C for 0.5 to 8 hours. Good 4vc to 80℃1
It is preferable to select conditions such that the copolymerization is completed at 20° C. in 2 to 4 hours. In this case, taper polymerization is also a preferred method.

Furthermore, during the copolymerization, additives such as ultraviolet absorbers, antioxidants, various stabilizers, anti-coloring agents, antistatic agents, silicon dyes, etc. may be selected and used as necessary. @ru.

In order to specifically explain the history of the present invention, comparative examples and examples will be described below, but the present invention is not limited to these examples.

In addition, all physical properties of the n-filter refractive index resins obtained in the Examples and Comparative Examples were measured using the following test methods.

(1) Refractive index was measured at 20°C using Atsube's refraction i\t'. J contact A! Motupromnaphthalin was used as the solution Ii.

(2) Surface condition of cast polymer: Visually observe the entire surface (front and back) of the cast polymer. ○ when both the front and back surfaces are smooth, △ when there is some unevenness, and △ if there is unevenness on the entire surface. The case where it was viewed was designated as X. Furthermore, 10
The number of sheets in which 7'Lf of polymerization occurred among the sheets combined trlk
Expressed as n/10.

(3) Cast polymerization, product generation PA temperature center Ji t 5 mm, edge n 7.0, a circumferential constantan thermocouple was installed inside the mold, and the exothermic temperature of the cast polymer when cured at 80°C was measured. did.

(4) Dyeing unevenness when dyed with a dyeable disperse dye at 90'CX for 10 minutes is shown below.

○ indicates that the entire surface is dyed uniformly, △ indicates that the dye is partially unevenly dyed, and × indicates that the entire surface is unevenly dyed.

(Function) It is presumed that the unevenness on the surface of the cast polymer is caused by the hardening and shrinkage of the resin during molding and the separation of the resin from the mold. Furthermore, since the cavities Ji in the mold are non-uniform, the heat generated by the resin 1 is different, and the amount of shrinkage is also different.

Therefore, in order to prevent the occurrence of unevenness on the surface of the perspiration type polymer, it was considered important to make the exothermic temperature of the resin in the cavity as uniform as possible and to equalize the amount of shrinkage as much as possible. 2,4-diphenyl-4-methylpentene used in the present invention acts as a chain transfer agent for radical N4 and suppresses curing heat generation during radical polymerization. As a result, by uniformizing the polymerization heat generation temperature, the lens optical It is thought that the distortion will not improve.

(Example) Examples 1 to 4 To each of the resin compositions No. 1 to 4 shown in Table 1, 1.0 parts by weight of sibiparate in tertiary hexyl silver was added as a radical polymerization initiator, and 2- 2.0 parts by weight of 4-diphenyl-4-methyl-1-pentene was added and thoroughly mixed. This mixed solution was mixed with a glass plate with a diameter of 80mm and a gasket made of ethene-vinyl acetate copolymer, with a center thickness of 1°5tnta-edge thickness 0ffIII.
The mixture was poured into a mold of 1, and cast polymerization was performed. Polymerization was carried out using an air oven, and the mixture was maintained at 80°C for 2 hours, and then at 100°C for 2 hours.

After the polymerization was completed, the mold was taken out from the all-air oven, the gasket was removed, and the polymer was peeled off from the glass plate after being allowed to cool. Various physical properties of the polymer were measured and the results shown in Table 1 were obtained.

Comparative Examples 1 to 4 Examples 1 to 4 except that 2-4-diphenyl-4-methyl-1-pentene was not used in Examples 1 to 4.
4 and all < l? The results are shown in Table 1.

[t°-r' (Effect of the invention) As is clear from the results shown in Table 1, the present invention has the following effects:
It has become possible to mold high refractive index plastic lenses with very good surface conditions in a short time, and the dyeability of the lenses has also been improved.

Claims (1)

[Claims] 1. The diacrylate or dimethacrylate compound (A) having an aromatic ring and the radically polymerizable compound (B) have a decomposition temperature of 50 to 1 to obtain a half-life of 10 hours.
Organic peroxide and 2,4-diphenyl-
A method for producing a high refractive index plastic lens, which comprises copolymerizing in the presence of 4-methyl-1-pentene.