JPH11167006A - Synthetic resin lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a lens which may be easily produced and has optical characteristics and mechanical characteristics good at a high refractive index and low sp. gr. and has good dyeability by consisting of the lens of a specific copolymer. SOLUTION: The phenethyl alcohol of the formula is defined as a component A, a compd. contg. a radial polymerizable unsatd. group and a hydroxyl group as a component B and thiol of >=20% in sulfur content as component C. The copolymer constituting the lens is obtd. by copolymerizing a compsn. consisting of 20 to 80 wt.% component E which is the reaction product obtd. by reaction of 80 to 100 wt.% of the total weight of the hydroxyl groups of the component A and the component B and a mercapto group of the component C with the isocyanate group of the arom. diisocyanate compd. not contg. the radical polymerizable unsatd. group and 80 to 20% monomer copolymerizable with the component E. The refractive index thereof is >=1.58, the sp.gr. <=1.2. The weight ratio of the component A and the component B is 20:80 to 80:20 and the weight ratio of the component A and the component C is 20:80 to 100:0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin lens, and more particularly to a lightweight synthetic resin lens made of a copolymer having good optical and mechanical properties.

[0002]

2. Description of the Related Art Conventionally, various inorganic glass lenses have been used in optical lenses.
Synthetic resin lenses have begun to be widely used together with inorganic glass lenses because of their light weight, processability, stability, dyeability, mass productivity, cost reduction, and the like.

Although various physical properties are required for optical lens materials, it is particularly important that they have a high refractive index, a low dispersion and a low specific gravity. That is, if the lens used is made of a material having a high refractive index and a low specific gravity, for example, a microscope, a camera, a thinner lens system occupying an important position in an optical device such as a telescope or an eyeglass lens,
It is possible to reduce the weight.

[0004] Therefore, there is a tendency to further reduce the specific gravity of the lens material made of synthetic resin and emphasize the superiority over the inorganic glass lens material.

For example, a diethylene glycol bisallyl carbonate resin called "CR-39" is currently most widely used as a lens material made of synthetic resin for spectacles. However, the specific gravity of this resin is 1.31 (temperature 20 ° C.
Means the value at. The same applies hereinafter. ) And relatively high.

On the other hand, as lens materials made of synthetic resin having a relatively low specific gravity, thermoplastic resins such as polystyrene (specific gravity; 1.02), polymethyl methacrylate (specific gravity; 1.20), and polycarbonate (specific gravity; 1.19) are used. However, these do not have sufficient dyeability and workability required practically as eyeglass lenses.

On the other hand, as a synthetic resin lens material having excellent physical properties such as heat resistance, solvent resistance and mechanical strength, a copolymer having a crosslinked structure is introduced.
A lens material made of a sulfur-containing urethane resin proposed in JP-A-46213 and JP-A-2-270859 has been put to practical use. However, since the synthetic resin lens material has poor storage stability of raw materials, it is necessary to store isocyanate and thiol separately. Therefore, the isocyanate and the thiol must be mixed immediately before use. Further, by mixing the isocyanate and the thiol, the viscosity of the mixed solution increases with time, and finally, the mixture may not be able to be injected into the mold due to the high viscosity. As described above, this synthetic resin lens material is extremely inconvenient to handle during use.

[0008]

As described above, the conventional synthetic resin lens material does not achieve a sufficiently low specific gravity or is extremely inconvenient in handling raw materials, so that it has a high refractive index and a low refractive index. There is a strong demand for the development of an optical material having a specific gravity and easy handling of a raw material when used, and also having good optical characteristics. The present invention has been made based on such circumstances, and the purpose is to eliminate the necessity of mixing the two liquids immediately before use and to avoid the inconvenience of thickening during operation, thereby facilitating production. Another object of the present invention is to provide a synthetic resin lens having a high refractive index, a low specific gravity, and good optical properties, mechanical properties and good dyeability.

[0009]

In the synthetic resin lens of the present invention, the weight ratio of phenethyl alcohol of the component A to the compound containing both the radically polymerizable unsaturated group and the hydroxyl group of the component B is A: B = 20:80 to 80:20, the weight ratio of the thiol compound having a sulfur content of 20% or more of the component A and the component C is A: C = 20: 80 to 100: 0, and
A reaction product in which 80 to 100% by weight of the total amount of the hydroxyl group of the component, the hydroxyl group of the component B, and the mercapto group of the component C reacts with the isocyanate group of the aromatic diisocyanate compound containing no radically polymerizable unsaturated group of the component D. A copolymer obtained by copolymerizing a composition consisting of 20 to 80% by weight of component E as a product and 80 to 20% by weight of component F as a monomer copolymerizable with component E. Wherein the lens is made of a synthetic resin.

In the present invention, the sulfur content is a value determined by the following equation.

[0011]

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below.

The copolymer constituting the high-refractive-index, low-specific-gravity resin lens of the present invention is a compound containing both phenethyl alcohol of the following structural formula of the component A and both a radically polymerizable unsaturated group and a hydroxyl group of the component B. And a thiol having a sulfur content of 20% or more of component C and a component E, which is a reaction product of an aromatic diisocyanate compound containing no radically polymerizable unsaturated group of component D, and a copolymerizable monomer F
It is obtained from the components.

[0014]

Embedded image

The hydroxyl group of the compound containing both the phenethyl alcohol of the component A and the radical polymerizable unsaturated group and the hydroxyl group of the component B, and the mercapto group of the thiol having a sulfur content of 20% or more of the component C are the radicals of the D component. A urethane bond is formed with the isocyanate group of the aromatic diisocyanate compound containing no polymerizable unsaturated group, whereby a high refractive index copolymer having dyeability is obtained.

The weight ratio B / A of the component A and the component B is 0.25.
If it is less than 4.0 or more than 4.0, it is difficult to reduce the specific gravity.

The weight ratio C / A of the component A and the component C is 4.
Even when it exceeds 0, it is difficult to reduce the specific gravity.

If the sulfur content of the component C is less than 20%, it is difficult to increase the refractive index.

In the present invention, the compound used as the component A is phenethyl alcohol.

In the present invention, specific examples of the compound containing both a radically polymerizable unsaturated group and a hydroxyl group used as the component B include 2-hydroxy-1,3-dimethacryloxypropane and 2-hydroxy-3. -Acryloyloxypropyl methacrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, and the like. However, it is not limited only to these.

In the present invention, specific examples of the thiol having a sulfur content of 20% or more used as the component C include ethylene glycol dithioglycolate (EGTG) and trimethylolpropane tristhioglycolate (TMT).
G), pentaerythritol tetrakisthioglycolate (PETG), pentaerythritol tetrakis-β
-Thiopropionate (PETP), ethylene glycol dithiopropionate (EDTP), butanediol dithioglycolate (BDTG), dimercaptotriethylene disulfide (DMTDS), dimercaptodiethylene sulfide (DMDS), 1,5,10 -Decanetrithiol, 1,10-decanediol, m-xylylenedithiol, p-xylylenedithiol, and the like, but are not limited thereto.

In the present invention, specific examples of the aromatic diisocyanate compound containing no radically polymerizable unsaturated group used as the component D include m-isopropenyl-α, α-dimethylbenzyl isocyanate and m-xylylene diisocyanate. , 4,4'-diphenylmethane diisocyanate and the like, but are not limited thereto.

The urethane reaction that occurs between the components A, B, C, and D can be carried out without heating under heating, or can be carried out using a catalyst to accelerate the reaction.

As the catalyst, those known in the field of polyurethane chemistry can be used, and a typical example is an organometallic catalyst. Specific examples include, for example, dibutyltin dilaurate, stannas octoate, and other organic tin compounds.

Further, in the present invention, 80% by weight or more of the total amount of the hydroxyl group of the component A and the component B and the mercapto group of the component C is used in addition to the component E which is a reaction product obtained by reacting with the isocyanate group of the component D. The component F, which is a monomer copolymerizable with the component E, is used as an essential component, whereby the characteristics of the finally obtained lens can be improved, and a resin lens having characteristics suitable for the purpose can be obtained. In addition, it is possible to preferably change the conditions for manufacturing the lens. For example, various physical properties required for a lens such as solvent resistance and scratch resistance can be improved, and the viscosity of the E component which is a reaction product can be reduced to facilitate casting polymerization. It can be carried out.

It is preferable that the monomer of the F component does not greatly increase the specific gravity of the lens finally obtained. In particular, the specific gravity of the polymer when polymerized alone is preferably 1. It is desirable to use a monomer having 2 or less as the F component. Examples of the monomer used as the F component include (a) styrene, α-methylstyrene,
Aromatic vinyl compounds such as divinylbenzene, diisopropenylbenzene, and vinyltoluene; various methacrylates or acrylates such as (b) benzyl (meth) acrylate and phenyl (meth) acrylate;
That is, esters of an aromatic compound having a monovalent hydroxyl group with (meth) acrylic acid, and the like can be given. However, it is not limited to only these examples. One or more of the above-described F components can be used in combination depending on the purpose.

In the present invention, the proportion of the component E as a reaction product needs to be 20 to 80% by weight, preferably 30 to 70% by weight of the whole composition. The amount of the component means that it is in the range of 80 to 20% by weight, preferably 70 to 30% by weight, based on the total amount of the monomer composition including the components A to D. 1 to 1 mole of isocyanate group of component D
By introducing the A component, the B component, and the C component such that 1.25 times the number of moles of hydroxyl groups and mercapto groups are present,
80 of the hydroxyl group of the component A and the component B and the mercapto group of the component C
１００100% by weight reacts with isocyanate groups of component D. In component E, which is a reaction product of components A to D, the number of hydroxyl groups and mercapto groups reacted with isocyanate groups is 8 or less.
If the amount is less than 0% by weight, it is difficult for the resin lens to obtain various physical properties required for the lens, such as heat resistance and impact resistance. When the proportion of the component E, which is a reaction product of the components A to D, is less than 20% by weight, the resin lens can obtain various physical properties required for the lens such as solvent resistance and scratch resistance. , And the polymerization shrinkage increases, resulting in poor moldability and surface accuracy. Conversely, if the component E exceeds 80% by weight, the viscosity of the mixture is too high, resulting in poor workability.

The low-density resin lens of the present invention is produced by reacting and polymerizing an appropriate mixture or composition of the above-mentioned component A to component F which satisfies the above-mentioned conditions. By appropriately combining the above components, the viscosity of the mixture or the composition can be sufficiently reduced and the fluidity can be made sufficiently high. Thus, the low-density resin lens of the present invention has a great advantage in that it can be manufactured very easily and at low cost.

As a casting polymerization method or a casting reaction method using a casting container, a well-known technique can be used as it is. And as a casting container, a plate shape, a lens shape,
A cylinder, prism, cone, sphere, and other molds or molds designed according to the intended use are used. The material may be any suitable material such as inorganic glass, plastic, metal and the like.

In the case where the lens of the present invention is obtained by the cast polymerization method, the components A to F are charged into a suitable casting container as a mixture or separately, together with a polymerization initiator, and the reaction and polymerization are carried out. The reaction may be performed, but the urethane reaction and the radical polymerization may be performed at the same time, or one of the polymerization or the reaction may be performed first, and then the other of the polymerization or the reaction may be performed.

The radical polymerization can be carried out at room temperature or in a heated state using a known radical polymerization initiator, whereby a polymer having a high molecular weight can be obtained.

In carrying out the casting polymerization method, each component may be put into the casting container at once, or a certain amount of polymerization or reaction may be carried out in advance using another container as needed. A lens can be obtained by putting the obtained prepolymer or syrup into a casting container and completing the reaction and polymerization. In addition, the mixture of each component may contain a coloring agent, an ultraviolet absorber, a heat stabilizer, and other auxiliary materials according to the expected use of the obtained lens.

The lens of the present invention is characterized in that the lens material is the above copolymer. Therefore, in addition to the method of directly obtaining a lens by a cast polymerization method, a plate material or other copolymer is obtained. Depending on the method of shaving from this,
Can be manufactured. Also, by dipping the lens in a staining solution or the like, it is possible to make the lens a desired color or apply gradation.

In order to further increase the surface hardness, it is possible to coat an inorganic or organic hard coating agent by means such as vapor deposition or dipping, and to apply a non-reflective coating.

[0035]

The reason why such an effect is obtained is that, in this copolymer, phenethyl alcohol of component A has a dyeing property, is a compound having a higher refractive index, and isocyanate group of aromatic diisocyanate of component D is further added. This makes it possible to obtain a high-viscosity, low-shrinkage reactive compound by further reacting with a copolymerizable and low-specific-gravity monomer, followed by copolymerization.

The high refractive index / low specific gravity resin lens of the present invention has a specific relative ratio of the A component, the B component, the C component, and the D component, and a ratio of the total amount of these four components to the whole. At a ratio within the range, a copolymer obtained by polymerizing with a specific F component,
In this reaction and polymerization, 80 to 100% by weight of the hydroxyl groups of the A component and the B component and the mercapto group of the C component are reacted with the isocyanate group of the D component, and furthermore, by utilizing the radical polymerizability of the B component and the F component. It can be obtained by polymerizing, and forming the thus obtained copolymer resin having a urethane bond into a lens.

[0037]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The measurement methods and evaluation results of various properties of the obtained polymer are as follows.

(1) Refractive index (n _D ) and Abbe number (ν)
_D ) A test piece of 10 mm × 20 mm × 3 mm was prepared, and the refractive index (n _D ) and the Abbe number (ν _D ) at room temperature were measured using “Abe Refractometer 1T” manufactured by Atago. The contact liquid used was α-bromonaphthalene.

(2) Specific gravity A test piece having a size of 10 mm × 20 mm × 3 mm was prepared and measured using “SGM-6” manufactured by METTLER TOLEDO.

(3) Solvent Resistance After immersing a -3D lens at 70 mm in a solvent (ethanol, acetone, methyl ethyl ketone, tetrahydrofuran, toluene) for 10 hours, it was determined whether the lens surface was damaged.

(4) Dyeability A 70 mm-thick flat lens is placed in a 90 ° C. dyeing solution (dye Seiko Plassel Brown diluted 1000 times with water).
After dipping for 0 minute, the total light transmittance was measured with an ultraviolet / visible spectrophotometer “UV-2200” manufactured by Shimadzu Corporation. Those having a total light transmittance of 40% or less were regarded as having good dyeability.

Example 1 A component PhA 14.0 g (14.0%), B component 70
2A 18.0 g (18.0%), D component XDI 1
6.0 g (16.0%), F component St 40.0 g (4
0.0%), 12.0 g (12.0%) of DVB, 0.1 g of dibutyltin dilaurate, a urethane polymerization initiator, was added to 100 g of the mixture, and the mixture was stirred at 55 ° C. for 5 hours to form hydroxyl and isocyanate groups. After pre-polymerization,
Radical polymerization initiator t-Butyl peroxy p
Ivalate (PB-ND) (1.0 g) was added, and the completely dissolved resin solution was injected into a casting mold composed of two glass plates and a gasket to perform polymerization. The polymerization was carried out by using a hot-air circulation furnace, gradually raising the temperature from 50 ° C. to 100 ° C. over 10 hours, maintaining the temperature at 100 ° C. for 1 hour, and then gradually cooling to 65 ° C.

The molded product had a refractive index of 1.58 or more and a specific gravity of 1.2 or less, was colorless and transparent, had no striae, distortion, or peeling, and had good dyeability.

Examples 2 to 4 and Comparative Examples 1 to 4 Polymerization compositions were prepared at the composition ratios (weight basis) shown in Tables 1 and 2, and 0.1 g of a urethane polymerization initiator dibutyltin dilaurate was added to 100 g of the polymerization composition. After pre-polymerizing a hydroxyl group and an isocyanate group or a hydroxyl group and a mercapto group and an isocyanate group by stirring at 55 ° C. for 5 hours, a radical polymerization initiator t-Butyl peroxy pi
1.0 g of valate (PB-ND) was added, and the completely dissolved resin solution was injected into a casting mold composed of two glass plates and a gasket to perform polymerization. The polymerization was carried out by using a hot-air circulation furnace, gradually raising the temperature from 50 ° C. to 100 ° C. over 10 hours, maintaining the temperature at 100 ° C. for 1 hour, and then gradually cooling to 65 ° C. The physical properties of the obtained polymer are shown in Tables 1 and 2. In any of the compositions of Examples 2 to 4, a molded article having a refractive index of 1.58 or more and a specific gravity of 1.2 or less, and was colorless and transparent, and free from defects such as striae, distortion, and peeling was obtained.

In Comparative Example 1 in which the weight ratio B / A exceeded 4.0, the molded article had a specific gravity higher than 1.2. Comparative Example 2 in which the weight ratio C / A exceeds 4.0, the F component was 20% by weight.
Comparative Example 3 having a refractive index of less than 1.58 or a specific gravity higher than 1.2 even in Comparative Example 4 using a thiol having a sulfur content of less than 20%. Could not be obtained.

[0046]

[Table 1]

[0047]

[Table 2] PhA (phenethyl alcohol) 702A (2-hydroxy-3-phenoxypropyl acrylate) PETP (pentaerythritol tetrakisthiopropionate) OTG (octyl thioglycolate) XDI (xylylene diisocyanate) TDI (tolylene diisocyanate) St (styrene) DVB (divinylbenzene)

[0048]

The synthetic resin lens according to the present invention has a high refractive index and a low specific gravity, and has good mechanical properties, optical properties and dyeability.

Claims (1)

[Claims] 1. The weight ratio of the phenethyl alcohol of the following structural formula of the component A to the compound containing both the radically polymerizable unsaturated group and the hydroxyl group of the component B is A: B = 20: 80-8.
0:20, and the weight ratio of the A component to the thiol compound having a sulfur content of 20% or more of the C component is A: C = 20: 80 to 1
00: 0, and 80 to 100% by weight of the total amount of the hydroxyl group of the component A and the component B and the mercapto group of the component C is D
20 to 80% by weight of a component E, which is a reaction product obtained by reacting with an isocyanate group of an aromatic diisocyanate compound containing no radically polymerizable unsaturated group, and a monomer F which is copolymerizable with the component E A copolymer obtained by copolymerizing a composition comprising 80 to 20% by weight of a component,
A synthetic resin lens having a refractive index of 1.58 or more and a specific gravity of 1.2 or less. Embedded image