JP2001124904A - Photo-curing plastic lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high refractive index photo-curing plastic lens having low specific gravity and a high Abbe's number, excellent in shock resistance, dyeability, transparency, etc., and easy to photopolymerize. SOLUTION: This photo-curing plastic lens comprises a copolymer obtained by photopolymerizing a composition, consisting of 10-90 wt.% phenyl phenol ethoxy acrylate of formula, 10-90 wt.%, another compound having a (meth) acrylic group and 0-50 wt.% monomer copolymerizable with these and has a refractive index of 1.58 or higher, specific gravity of 1.4 or lower and an Abbe's number of 30 or larger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens made of a synthetic resin, and more particularly, to a lens made of a photocurable resin having a high refractive index, which is suitable for mass production because the manufacturing process can be simplified.

[0002]

2. Description of the Related Art Conventionally, various inorganic glasses and synthetic resins have been used as optical lens materials. Various physical properties are required for optical lens materials. For example, in the field of spectacle lenses, high refractive index, high Abbe number, and low specific gravity are extremely important. In other words, if the lens used has a high refractive index and a low specific gravity, the lens can be made thinner and lighter, and if the lens has a high Abbe number, light dispersion is small and a comfortable wearing feeling can be obtained. Because.

In the field of spectacle lenses, as a material of a synthetic resin lens, there is a material called "CR-39" made from diethylene glycol bisallyl carbonate as a typical example at the beginning. The material was very lightweight compared to previous inorganic glass lenses, so it quickly penetrated the world. However, since this material has a low refractive index of about 1.50, the thickness of the entire lens becomes large, and it has never been satisfactory as a spectacle lens. Therefore, in order to reduce the thickness of the lens, research on increasing the refractive index has been actively conducted.
As a result, for example, a urethane resin material obtained by polymerizing thiol and isocyanate (Japanese Unexamined Patent Publication No.
And Japanese Patent Application Laid-Open No. 9-71580) achieves a refractive index of 1.60 or more, and further achieves a refractive index of 1.70 or more in an episulfide resin material containing an episulfide compound (JP-A-9-71580). The thinning of lenses has been rapidly accelerated. In fact, some of these have been put to practical use as high refractive index and ultra high refractive index resins.

[0004]

However, the above high refractive index resin is a synthetic resin obtained by a urethane reaction, and the ultra high refractive index resin is a synthetic resin obtained by an episulfide ring opening reaction, and both require a long heat curing time. , A synthesis method by thermal polymerization was required. For example, in the field of spectacle lenses, the polymerization time is as long as about 10 to 20 hours, so that the glass mold used in manufacturing the lens has a long time, which is not suitable for mass production.

On the other hand, a method for producing a spectacle lens using photopolymerization is suitable for mass production because the polymerization time is as short as about several minutes, and the time for occupying a glass mold is short.

Here, as a material capable of photopolymerization, for example, a material obtained by preparing a prepolymerized product (prepolymer) of a thiol and a vinyl monomer (JP-A-4-578)
No. 31) and a material using a novel sulfur compound (JP-A-8-183816) are proposed. These materials are high-refractive-index materials capable of photopolymerization as well as thermal polymerization, and in fact, some of them have a refractive index of 1.60.
Some have achieved the above.

However, for example, in a material obtained by preparing a prepolymerized product of a thiol and a vinyl monomer,
Since a complicated preliminary polymerization step is required during photopolymerization, there is a problem that the lens manufacturing time is not shortened much,
In addition, mass production technology has not been established for materials using new sulfur compounds because of the new substances. In addition, costs are high, specific gravity is high, and impact resistance, Abbe number, dyeability, transparency, etc. At present, there are numerous problems, such as insufficient characteristics required for the optical lens.
Actually, only a lens made of a photocurable resin employing photopolymerization and having a low refractive index has been put to practical use.

As described above, high-refractive-index materials that have been put to practical use so far have a problem in mass productivity due to the difficulty of photopolymerization, and high-refractive-index materials that can be photopolymerized are: There are many problems such as insufficient properties required for optical lenses such as impact resistance and Abbe number, and complicated manufacturing steps are required, so that the production time is not shortened much. Was difficult.

Accordingly, an object of the present invention is to provide a high-refractive-index photocurable resin lens having a low specific gravity, a high Abbe number, excellent impact resistance, dyeability, transparency, etc., and easy photopolymerization. To provide.

[0010]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies on such a situation, and as a result, it has been found that a copolymer containing an acrylic compound having a specific structure is synthesized by thermal polymerization. However, even though the heat resistance and impact resistance of the optical lens could not be achieved, when synthesized by photopolymerization, the properties required for the optical lens, such as heat resistance and impact resistance, were also sufficient. The present invention has been found to be very excellent, and the present invention has been completed.

That is, the present invention provides a phenylphenol ethoxy acrylate 10 represented by the following structural formula (1).
To 90% by weight, another 10 to 90% by weight of a compound having a (meth) acrylic group, and 0 to 50% by weight of a monomer copolymerizable therewith. A lens made of a photocurable resin, which is made of a united material, has a refractive index of 1.58 or more, a specific gravity of 1.4 or less, and has an Abbe number of 30 or more.

[0012]

Embedded image (In the formula, n represents an integer of 1 to 3.) In the present invention, the above-mentioned excellent physical properties are obtained by photopolymerizing a composition that is easily photopolymerizable and composed of a specific component. Resin is easily manufactured in a short time.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The photocurable resin of the present invention is obtained by adding phenylphenol ethoxy acrylate of the structural formula (1) to 1
The content is 0 to 90% by weight, preferably 20 to 80% by weight. The reason is that when the amount of phenylphenol ethoxy acrylate is less than 10% by weight, it is difficult to achieve the high refractive index which is a feature of the present invention. This is because it becomes difficult to maintain mechanical properties required for the optical lens, such as heat resistance and impact resistance. Further, when n exceeds 3,
Since it becomes difficult to achieve a high refractive index which is a feature of the present invention, it is necessary that n = 1 to 3.

Further, the photocurable resin of the present invention contains a compound having a (meth) acryl group other than those described above in an amount of 10 to 90% by weight, preferably 20 to 80% by weight. The reason is that if it is less than 10% by weight, it becomes difficult to maintain the properties required for the optical lens such as heat resistance and impact resistance, and if it exceeds 90% by weight, This is because it is difficult to achieve a high refractive index which is a feature of the present invention.

At this time, any compound having a (meth) acryl group can be used. Examples include monofunctional acrylic compounds such as hydroxyethyl acrylate (HEA), hydroxypropyl acrylate (HPA), phenoxy polyethylene glycol acrylate (PEA), ethylene glycol diacrylate (EDA), neopentyl glycol diacrylate (NPG), polyethylene Polyfunctional acrylic compounds such as glycol diacrylate (PEDA), tetramethylolmethane triacrylate (TMM), bis-2-acryloylthioethyl sulfide (A-TES), 1,4-bisacryloylthiobenzene (BATB), and hydroxyethyl Monofunctional methacrylic compounds such as methacrylate (HEMA), hydroxypropyl methacrylate (HPMA) and benzyl methacrylate (BZMA); Call dimethacrylate (ED), 2
-Hydroxy-1,3-dimethacrylate (HDP),
2,2-bis (4-methacryloxypolyethoxyphenyl) propane (BPE), trimethylolpropane trimethacrylate (TMPT), bis-2-methacryloylthioethyl sulfide (TES), 1,4-bismethacryloylthiobenzene (BMTB) ) And the like, but are not limited thereto.

The compound having a (meth) acrylic group to be contained at this time is not necessarily required to be one kind, and if necessary, two or more kinds can be used in combination. In addition, since the phenylphenol ethoxy acrylate of the structural formula (1), which is an essential component in the present invention, is a monofunctional acrylic compound, the compound having a (meth) acryl group contained at this time has many It is preferable that a functional (meth) acrylic compound is contained.

The photocurable resin of the present invention may further comprise, if necessary, a monomer copolymerizable with these components in addition to the above components in order to impart various properties to the obtained resin. it can. However, if it is added in excess of 50% by weight, it becomes difficult to obtain sufficient impact resistance as an optical lens, so the addition amount is 0 to 50% by weight.

The monomer at this time may be any monomer as long as it can be copolymerized with the above components. However, in order to achieve the high refractive index characteristic of the present invention, the monomer itself must be used. It is preferable that the refractive index is as high as possible. Examples include styrene (St), vinyl compounds such as α-methylstyrene dimer (MSD), allyl benzoate (AK
A), allyl esters such as diallyl phthalate (FDA), polyfunctional thiols such as pentaerythritol tetrakisthioglyconate (PETG), pentaerythritol tetrakisthiopropionate (PETP), and the like, but are not limited thereto. Not something.

The photocurable resin of the present invention can reduce the viscosity of the composition by a combination of the above-mentioned components, and make the composition sufficiently flowable. After the injection, it is possible to carry out the photopolymerization collectively, and therefore, it is possible to produce easily and at low cost.

The present invention is a copolymer comprising the above composition. However, when the above composition is polymerized by thermal polymerization, heat resistance and impact resistance are insufficient, and only when polymerized by photopolymerization, the heat resistance and impact resistance required for an optical lens are obtained. be able to. Therefore, the present invention is characterized in that it is a copolymer obtained by photopolymerizing the above composition.

For the photopolymerization, a known photopolymerization technique can be applied. That is, for example, after injecting the composition into a casting container or the like, a high molecular weight copolymer can be obtained by a method of irradiating a light beam such as an ultraviolet ray or an electron beam.

In the photopolymerization at this time, if necessary, a photopolymerization initiator (photosensitizer) can be added. For example, when performing photopolymerization by a method of irradiating ultraviolet rays, in order to obtain a copolymer in a shorter time, in advance,
It is desirable to add a photopolymerization initiator to the composition. The photopolymerization initiator added at this time is not necessarily required to be one kind, and two or more kinds can be used in combination as needed. However, if the addition amount is too large, the properties required for the optical lens such as the refractive index and impact resistance are reduced. Therefore, the addition amount of the photopolymerization initiator is preferably 10% by weight or less, more preferably 8% by weight. % By weight or less.

As the photopolymerization initiator at this time, known photopolymerization initiators such as acetophenones and benzophenones can be used. Examples of the photopolymerization initiator include α-
Hydroxyisobutylphenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2-hydroxy-2-benzoylpropane, benzyldimethyl ketal, thioxane, 2-chlorothioxanthone, azobisisobutyronitrile, etc. But are not limited to these.

The mixture of the components may contain a coloring agent, a heat stabilizer, and other auxiliary materials, if necessary. Further, a hard coat agent, a non-reflective coat, or another surface coat can be applied to the surface of the obtained copolymer.

The photocurable resin of the present invention is characterized in that it is a copolymer as described above. Therefore, in addition to the casting polymerization method, the photocurable resin is cut after obtaining a plate material or other copolymer. It can also be manufactured by the method of dispensing.

[0026]

The present invention will be described in more detail with reference to the following examples.
The present invention is not limited to these. In addition, the evaluation methods of the obtained various physical properties are as follows.

Refractive index A test piece of 10 mm × 20 mm × 3 mm was prepared, and the refractive index at room temperature (20 ° C.) was measured using “DR-M2” manufactured by Atago, using α-promonaphthaline as a contact liquid. did.

Abbe Number The Abbe number was measured by the same measuring device and measuring method as used for the above-mentioned refractive index measurement.

A test piece having a specific gravity of 10 mm × 20 mm × 3 mm was prepared, and the specific gravity was measured using “SGM-6” manufactured by METTLER TOLEDO.

Impact resistance Ten test samples having a diameter of 78 mm, a radius of curvature of 0.1 m, and a center thickness of 2 mm were prepared, and a steel weighing 16.2 g (about 1.59 cm (10/16 inch) in diameter) was prepared. Sphere 1.
It was dropped from a height of 27 m, and according to the standard of the FDA falling ball impact strength, all of the 10 pieces that did not crack were considered as good.
Any piece that was cracked was regarded as defective.

Stainability A dye solution was prepared by mixing 1 g of Seiko Plux Brown manufactured by Hattori Seiko Co., Ltd. with 1000 ml of pure water and an auxiliary agent, and the obtained lens was added to the dye solution.
Dyeing is performed by immersion at 2 ° C. for 10 minutes, and the total light transmittance is measured using an ultraviolet-visible spectrophotometer “UV-2200” manufactured by Shimadzu Corporation. The ones exceeding the above were regarded as defective.

Transparency A flat plate having a center thickness of 2.0 mm was prepared and “H” manufactured by Suga Test Instruments Co., Ltd.
The haze was measured using "GM-2DP" and the haze was 0.3
The following were rated good, and those exceeding 0.3 were rated poor.

Example 1 50 g of phenylphenol ethoxy acrylate (OPP), 50 g of BPE, and the above were measured in a 200 ml beaker, and then a photopolymerization initiator, IRGACURE 184 (manufactured by Nippon Ciba Geigy).
Was added to a casting mold composed of two glass plates and a gasket, and irradiated by an ultraviolet irradiation device under the conditions of an irradiation dose of 800 mW / cm ² , an irradiation distance of 50 cm, and an irradiation time of 10 min. UV polymerization was performed. Thereafter, the copolymer was taken out of the casting mold to obtain a finished product.

The obtained copolymer has physical properties as shown in Table 1, and has a refractive index of 1.58 or more, an Abbe number of 30 or more,
A molded article having a specific gravity of 1.40 or less and excellent impact resistance, dyeing properties, and transparency was obtained.

Example 2 50 g of phenylphenol diethoxy acrylate (OPP-2) and 50 g of BPE
g, the above was measured in a 200 ml beaker, and then 1000 ppm of a photopolymerization initiator, IRGACURE 184 (manufactured by Nippon Ciba Geigy), was added, and the mixture was stirred sufficiently.
Injected into a casting mold composed of two glass plates and a gasket, and irradiated with an ultraviolet irradiation device at an irradiation dose of 800 mW / cm.
^{2. Under} the condition of irradiation distance 50cm and irradiation time 10min,
UV polymerization was performed. Thereafter, the copolymer was taken out of the casting mold to obtain a finished product.

The obtained copolymer has physical properties as shown in Table 1, and has a refractive index of 1.58 or more, an Abbe number of 30 or more, and
A molded article having a specific gravity of 1.40 or less and excellent impact resistance, dyeing properties, and transparency was obtained.

Examples 3 to 5 The polymerization compositions were mixed at the composition ratios shown in Table 1 and the photopolymerization initiator IRGACURE1 was used.
84 After stirring thoroughly added 1000ppm (Japan Ciba Geigy Co.), poured into casting molds constituted by two glass plates and a gasket of at ultraviolet irradiation device, irradiation dose 800 mW / cm ^2, irradiation distance Ultraviolet polymerization was performed under the conditions of 50 cm and an irradiation time of 10 min. Thereafter, the copolymer was taken out of the casting mold to obtain a finished product.

The obtained copolymers were able to obtain physical properties as shown in Table 1. In Examples 3 to 5,
All had a refractive index of 1.58 or more, an Abbe number of 30 or more, and a specific gravity of 1.40 or less, and molded articles excellent in impact resistance, dyeing properties, and transparency were obtained.

Comparative Example 1 As shown in Comparative Example 1 of Table 1, phenylphenol ethoxy acrylate (OP
Photopolymerization was carried out in the same manner as in the above example with a composition in which P) exceeded 90% by weight. As a result, not only the Abbe number was 30 or less, but also two out of ten pieces were found to be damaged in the impact resistance test, and it was confirmed that there was a problem in Abbe number and impact resistance.

Comparative Example 2 As shown in Comparative Example 2 in Table 1, phenylphenol ethoxy acrylate (OP
Photopolymerization was carried out in the same manner as in the above example, with the composition of P) being less than 10% by weight. As a result, the refractive index was less than 1.58, and a problem was confirmed in the refractive index.

(Comparative Example 3) As shown in Comparative Example 3 of Table 1, photopolymerization was carried out in the same manner as in the above Example, with a composition of phenylphenolpentaethoxyacrylate (OPP-5) of 50% by weight. As a result, the refractive index was less than 1.58, and a problem was confirmed in the refractive index.

(Comparative Example 4) As shown in Comparative Example 4 in Table 1, the number of monomers copolymerizable with the (meth) acrylic compound was 5
With the composition exceeding 0% by weight, the same photopolymerization as in the above example was performed. As a result, not only the refractive index is less than 1.58 and the Abbe number is less than 30, but also
Eight of the 0 sheets were found to be damaged, confirming that there were problems with the refractive index, Abbe number, and impact resistance.

(Comparative Example 5) The compositions were mixed at the composition ratio as shown in Comparative Example 5 in Table 1 and the thermal polymerization initiators 2, 2
-Azobis (2,4-dimethylvaleronitrile) in 10
00 ppm was added, and the mixture was poured into a casting mold composed of two glass plates and a gasket, and polymerized by a method of thermal polymerization instead of photopolymerization. In the thermal polymerization, the temperature was gradually raised from 45 ° C. to 100 ° C. over 10 hours in a hot air circulating furnace, maintained at 100 ° C. for 2 hours, and then gradually cooled to 65 ° C. Thereafter, the copolymer was taken out of the casting mold to obtain a finished product.

In the impact resistance test, the obtained copolymer was found to be damaged in 3 out of 10 sheets, and it was confirmed that there was a problem in the impact resistance.

[0045]

[Table 1]

[0046]

According to the present invention, an optical lens having a high refractive index can be easily produced in a short time by copolymerizing a material composed of a specific component which is easily photopolymerized. In other words, in a short and simplified process,
In addition to good physical properties such as transparency, dyeability and impact resistance, lenses having a high refractive index can be easily mass-produced.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08F 220: 10 C08F 220: 10 212: 08) 212: 08) (72) Inventor Kenji Uno Bunkyo-ku, Tokyo 2-42, Hongo F-term in the seed company of the stock company (reference) 4J011 QA03 QA09 QA13 QA17 QA34 QA46 SA06 SA14 SA32 SA36 SA54 SA64 SA79 UA01 WA07 4J100 AL08P AL08Q AL09Q AL62Q AL63Q AL66Q AL67Q BA02Q BA03P BA08Q BA08P BA08Q08 DA11 DA63 FA17 JA33

Claims (1)

[Claims] 1. 10 to 90% by weight of phenylphenol ethoxy acrylate represented by the following structural formula (1), 10 to 90% by weight of another compound having a (meth) acrylic group, and a monomer copolymerizable therewith. 0 to 50% by weight
A lens made of a photocurable resin, comprising a copolymer obtained by photopolymerizing the composition of (1), having a refractive index of 1.58 or more, a specific gravity of 1.4 or less, and an Abbe number of 30 or more. Embedded image (In the formula, n represents an integer of 1 to 3.)