JPS6280602A - Plastic lens having high refractive index - Google Patents

Abstract

PURPOSE:To form a plastic lens having high refractive index and >=35 Abbe's number and >=1.60 refractive index by constituting the lens of specified recurrent structural units as principal component. CONSTITUTION:A plastic lens is constituted of recurrent structural units expressed by the formula I as principal component. In the formula I, -CHmHnXp is a halogen-contg. aliphatic and/or halogen-contg. alicyclic group; R is H or methyl; X is a halogen atom except F; l is 1-3; m is 1-12; n+p is an integer 1-25. Since the plastic lens has >=1.60 refractive index, the thickness of the external periphery of the lens can be made thin. Further, since the lens has >=35 Abbe's number, the chromatic aberration of the lens is made smaller than the chromatic aberration of conventional lenses having high refractive index.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plastic lens with a high refractive index, excellent transparency and heat resistance, and with less noticeable chromatic aberration.

[Conventional technology]

Plastic lenses have become more widely used in optical products in recent years because they are superior to glass lenses in terms of light weight, workability, impact resistance, dyeability, etc. Among these, there is a particularly high demand for lightweight lenses for eyeglass lenses, and currently 40% of lenses are replaced by plastic.

Conventionally, diethylene glycol bisallyl carbonate resin (also referred to as OR-39) and polymethyl methacrylate (PMMA) have been mainly used as resins for eyeglass plastic lenses.

In particular, diethylene glycol bisallyl carbonate resin has excellent transparency and a beautiful appearance, has a crosslinked structure, has high surface hardness, and is excellent in processability. It is used a lot.

Furthermore, as prior art to the present application, Japanese Patent Publication No. 58-14449
Publication No. 17081/1981, Japanese Patent Publication No. 17081/1983
13747, JP 56-36601, JP 60-69114, JP 60-51706
There are publications, etc.

[Problem that the invention seeks to solve]

However, diethylene glycol bisallyl carbonate resin has a refractive index of 1.49 to 1.50, which is lower than the refractive index of ordinary glass lenses (1.5 to 1.6), so
When a lens is made of this resin, the outer periphery of the lens is thicker than that of glass, resulting in poor visibility. This is particularly noticeable when the power of the lens increases.

In addition, PMMA has the same problems as the diethylene glycol bisallyl carbonate resin, and since it is a two-dimensional polymer and thermoplastic, it has poor processability and is only used in some sunglass lenses and safety glasses. There is.

On the other hand, in the prior art, the refractive index (nO) is 1.
A resin with a fairly high refractive index around 6 (') was obtained, and the drawback of the increased thickness of the diethylene glycol bisallyl carbonate periphery was almost solved. Therefore, it had the disadvantage that chromatic aberration was relatively noticeable.A concrete example of the prior art is Japanese Patent Application Laid-Open No. 60-69114.
In Example 3 of the publication, a copolymer of dimethacrylate of a tetrabromobisphenol A derivative and methacrylate of a tribromophenol derivative has a refractive index (N, >1
．． 608 and is described as having an Abbe number (νo) of 34.

Furthermore, in Example 1 of JP-A No. 60-51706, a polymer of a reaction product of polyfunctional isocyanate and monohydroxy monoacrylate-1- of a tetrabromobisphenol A derivative has a refractive index (N,) of 1.61. and the Atsbe number (ν,
) 34.

Both resins are considerably lower than the number 58 of diethylene glycol bisallyl carbonate resin,
Chromatic aberration is relatively noticeable.

In view of the above drawbacks, the present invention aims to provide a high refractive index plastic lens having a refractive index of 1.60 or more and an Abbé number of 35 or more.

[Means for solving problems]

In order to achieve the above object, the present invention consists of the following configuration.

``A high refractive index plastic lens characterized by having a repeating structural unit represented by general formula I as a main component.

(In the formula, -CIIIH, xD represents a halogen-containing aliphatic group and/or a halogen-containing alicyclic group, R is hydrogen or a methyl group, X is a halogen atom excluding fluorine, Q = 1 to
3, m=1 to 12, and n+p=1 to 25.

)" That is, the present invention relates to a plastic lens having a structure obtained by reacting halogen-containing aliphatic or halogen-containing alicyclic (meth)acrylate.

1 of the halogen-containing aliphatic or halogen-containing alicyclic (meth)acrylate residues is not particularly limited, but 30% by weight or more is particularly effective. At 80% or more, when the monomer used is monocyclic (meth)acrylate, the properties as a thermoplastic resin are emphasized, so it is necessary to select the use of the plastic lens, the molding method, etc.

The halogen-containing aliphatic or alicyclic (meth)acrylate residue constituting the present invention can be achieved by polymerizing using the following monomers. For example, tribromneopentyl (meth)acrylate, trichlorneopentyl (meth)acrylate, dibromopropyl (meth)acrylate, dichloropropyl (meth)acrylate, brompropyl (meth)acrylate, chlorpropyl (meth)acrylate, trichlor These include ethyl (meth)acrylate, tribromoethyl (meth)acrylate, bromoethyl (meth)acrylate, dibromneopentyl glycol di(meth)acrylate, and mixtures thereof.

Particularly preferred among these is tribrome neopentyl methacrylate! - Libromneopentyl acrylate, dibrompropyl acrylate-1, dibromneopentyl glycol dimethacrylate.

The present invention uses 70% of other monomers copolymerizable with the above monomers.
It can be used within the range of heavy violence% or less. Examples of copolymerizable monomers include styrene and halogen-substituted styrene, and halogen-substituted phenol derivatives (
meth)acrylate, di(meth)acrylate of tetrabromobisphenol A derivative, monohydroxymono(meth)acrylate of tetrabromobisphenol A derivative, di(meth)acrylate-1~ of tetrabromobisphenol sulfone derivative, alkylene glycol di(meth) ) acrylate, diallylphthale-1-, diethylene glycol bisallyl carbon-1-, divinylbenzene, etc., and mixtures thereof.

The halogen-containing aliphatic (meth)acrylate residue or halogen-containing alicyclic (meth)acrylate residue constituted by the present invention can be analyzed by FI-IR, NMR, elemental analysis, GC, GC-M
S, can be easily confirmed by conventional analytical means such as HPLC.

The method for manufacturing the plastic lens of the present invention is carried out by a casting polymerization method. That is, halogen-containing aliphatic (meth)acrylate or halogen-containing alicyclic (meth)acrylate and other comonomers are mixed, and then a polymerization initiator, ultraviolet absorber, antioxidant, deodorant, and aroma imparting are added. Add various additives such as coloring agents and coloring dyes and mix and dissolve. After filtering this adjustment solution using a membrane filter, dissolved air and the like are removed under vacuum, and the solution is injected into a lens mold. Polymerization is initially carried out at a relatively low temperature, and the temperature is gradually raised to complete the polymerization. For example, 10 hours at 60℃, 5 hours at 80℃, 100℃
Polymerization was carried out at 110° C. for 5 hours and at 110° C. for 5 hours, followed by slow cooling and mold release.

Various known radical polymerization initiators can be used. For example, diisopropylperoxydicarbonate-1-, t-butylperoxypivale-1-, t-butylperoxyisopropylcarbonate-1-, di-t-
Filter with butyl peroxide, etc.

Preferably t-butyl peroxyisobutyrate, °C
- butylperoxyisopropyl carbonate.

The amount used can range from 0.005 to 3% by weight, but preferably from 0.01 to 0.1% by weight.

Various known additives such as ultraviolet absorbers and antioxidants can be used.

The lens mold consists of two glass plates that form the concave and convex surfaces of the lens, and a polyethylene gasket that holds them.
It is made up of.

The plastic lens of the present invention can be subjected to known surface modifications such as Bartco-1-1 antireflection, antifogging properties, abrasion resistance, and improved chemical resistance.

〔Example〕

Next, the present invention will be illustrated by examples. Various physical properties of the polymers obtained in the Examples were measured by the following test methods.

(1) Refractive index and Atsbe number Using a Pulfritsch refractometer, the wavelength is 589 at a temperature of 20°C.
．． 3 D line, 546.1 E line, 486.1 E
Measured under line conditions.

(2) Color tone The color tone of the lens molded product was visually determined.

(3) Flexural rigidity: Based on JIS K 7203. However, the shape of the test piece was 30 mm x 10 mm x 3 nwn, and the distance between the fulcrums was 22 nwn.

(4) Post-processability The appearance and optical stability of a molded lens after polishing, dyeing, hard coating, anti-reflection, anti-fog properties, etc.

Example 1 60 parts by weight of tribrome neopentyl acrylate, 25 parts by weight of dibrom styrene, and 15 parts by weight of divinylbenzene-HP (trade name: DVB-HP, manufactured by Dow Chemical Company) were mixed, and tert-butyl peroxide was added as a polymerization initiator. 0.03% by weight of oxyisopropyl carbonate was added and mixed well. After filtration using a membrane filter,
Dissolved gas such as air was vacuum degassed and injected into the lens mold.

The injection solution was easy to inject due to its low viscosity.

Polymerization was performed by first solidifying the contents at 60°C for 10 hours.
Polymerization was completed over roughly 5 hours at 80°C, 5 hours at 100°C, and 5 hours at 110°C.

The obtained polymer had a high refractive index (n,) of 1.61 and an excellent Abbe number (νD) of 37.

Other physical properties are shown in Table 1.

Example 2 75 parts by weight of tribromneopentyl methacrylate, 10 parts by weight of pentabromphenoxyethyl acrylate,
Divinylbenzene-HP (Dow Chemical Company product name: DV
B-HP) and 0.03 parts by weight of tert-butyl impropyl carbonate as a polymerization initiator.
% by weight was added.

This mixed solution was polymerized in the same manner as in Example 1,
Table 1 shows the physical properties of the obtained polymer.

It had very excellent optical properties, with a refractive index (n, >1.61) and an Abbe number (νD) of 41.

Examples 3-5. Comparative Examples 1 and 2 Lenses with different compositions were produced by the same method as in Example 1, and the results are shown in Table 1.

As is clear from Table 1, the lens according to the present invention has a high refractive index of 1.60 or more and an excellent Abbe number of 35 or more. Of course, the lens of the present invention was also excellent in casting workability, heat resistance, post-processability, and stability in framing.

(Effects of the Invention) The plastic lens of the present invention has the following characteristics compared to conventional plastic lenses.

■ Since the refractive index is 1.60 or more, the thickness of the outer periphery of the lens can be made thinner. Of course, there is also the advantage that the lens can be made lighter.

■ Since the Abbe number is 35 or more, it is possible to obtain a lens with smaller chromatic aberration than conventional high refractive index lenses.

■ Lenses with excellent heat resistance and post-processability can be obtained.

Claims (2)

[Claims] (1) A high refractive index plastic lens characterized by having a repeating structural unit represented by general formula I as a main component. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (In the formula, -C_mH_nX_p represents a halogen-containing aliphatic group and/or a halogen-containing alicyclic group, R is hydrogen or a methyl group, and X is a halogen atom other than fluorine. , l=1
-3, m=1-12, n+p=1-25. ) (2) The repeating structural unit represented by general formula I is 3 in the resin.
A high refractive index plastic lens according to claim (1), characterized in that the content is 0% by weight or more.