JP2001002635A - New polyisocyanate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject new compound useful as a monomer for a high- refractive index urethane-based transparent resin, a transparent optical material and a plastic lens, capable of satisfying the thinning of plastic lens and improvement in refractive index. SOLUTION: This polyisothiocyanate is shown by the formula such as 2,4-bis(isothiocyanatomethyl)norbornane, etc. The polyisocyanate of the formula can be obtained, for example, by reacting bis(aminomethyl)norbornane synthesized as a starting raw material with carbon disulfide in the presence of a base to give a dithiocarbamate, then reacting the dithiocarbamate with phosgene or an alkyl chloroformate, etc., and then thermally decomposing the resultant substance. The polyisocyanate of the formula is polymerized with a polythiol [e.g. pentaerythritol poly(3-mercaptopropionate, etc.), to provide a polyurethane- based transparent resin, a transparent optical material, a plastic lens, etc., having improved refractive index.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a urethane-based transparent resin, a polyisothiocyanate useful as a monomer for a transparent optical material and a plastic lens, a urethane-based transparent resin obtained by polymerizing the polyisothiocyanate, and a transparent optic. It relates to materials and plastic lenses.

[0002]

2. Description of the Related Art Urethane-based plastic lenses are now widely used by taking advantage of their tough properties. Above all, a urethane-based plastic lens using bis (isocyanatomethyl) norbornane gives a higher refractive index and a higher heat resistance than a plastic lens using other alicyclic polyisocyanate (Japanese Patent Publication No. 7-68326). For this reason, it is known as an excellent plastic lens.

[0003]

However, in recent years,
The demand for further reduction in the thickness of plastic lenses has become extremely strong, and the above-mentioned proposals alone have not been able to respond sufficiently to the demand for thinning because the refractive index is insufficient.

[0004]

[Means for solving the problem] In order to answer the request,
The present inventors have conducted intensive studies to further improve the refractive index while maintaining the excellent characteristics of a urethane-based plastic lens using bis (isocyanatomethyl) norbornane, and as a result, the following formula (1)

Embedded image If the new polyisothiocyanate represented by is polymerized with polythiol, the refractive index will be significantly improved, not only to meet the demand for thinner, but also to require a high refractive index other than plastic lenses. The present inventors have found that the present invention is useful for optical applications, and arrived at the present invention.

That is, the present invention provides a compound represented by the following formula (1):

Embedded image And a high-refractive-index urethane-based transparent resin, a transparent optical material, and a plastic lens obtained by reacting the polyisothiocyanate of the formula (1) with a polythiol.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The polyisothiocyanate of the formula (1) of the present invention is an organic compound in which two isothiocyanatomethyl groups are bonded to a norbornane skeleton. Therefore, the isothiocyanatomethyl group may be bonded to any position of the norbornane skeleton. If a typical compound is illustrated, for example, 2,4
-Bis (isothiocyanatomethyl) norbornane, 2,
5-bis (isothiocyanatomethyl) norbornane,
3,4-bis (isothiocyanatomethyl) norbornane, 3,5-bis (isothiocyanatomethyl) norbornane and the like can be mentioned.

The polyisothiocyanate of the formula (1) of the present invention is synthesized, for example, by the following method. In this method, bis (aminomethyl) norbornane is synthesized as a starting material, carbon disulfide is reacted in the presence of a base to produce a dithiocarbamate, and then phosgene or an alkylchloroformate is reacted to thermally decompose. .

[0008] Bis (aminomethyl) norbornane as a raw material is an organic compound in which two aminomethyl groups are bonded to a norbornane skeleton, like the polyisothiocyanate of the present invention. Therefore, the aminomethyl group may be bonded to any position of the norbornane skeleton. If a typical structure is illustrated, for example, 2,4-bis (aminomethyl) norbornane, 2,5-bis (aminomethyl) norbornane, 3,4-bis (aminomethyl) norbornane, 3,5-bis (Aminomethyl) norbornane.

When carbon disulfide is reacted with the starting diamine, a strong base is usually used. For example, sodium hydroxide, potassium hydroxide, aqueous ammonia and the like can be mentioned, and sodium hydroxide is preferably used.

The alkyl chloroformate to be reacted with the dithiocarbamate includes, for example, methyl chloroformate, ethyl chloroformate, propyl chloroformate, isopropyl chloroformate, butyl chloroformate and the like.

By reacting the above-mentioned alkylchloroformate or phosgene with a dithiocarbamate and then pyrolyzing it, or by sequentially pyrolyzing it while reacting,
The polyisothiocyanate of the present invention represented by the formula (1) is obtained.

As another typical method, there is a method of reacting thiophosgene with a diamine as a raw material.

The polyisothiocyanate represented by the formula (1) thus obtained is usually purified by distillation.

Next, the polyurethane-based transparent resin of the present invention,
A method for manufacturing a transparent optical material and a plastic lens will be briefly described using a plastic lens as an example. The polyisothiocyanate represented by the formula (1) of the present invention, polythiol, and if necessary, other monomers and additives are mixed and homogenized, and defoaming is performed by stirring under reduced pressure or the like. Thereafter, the defoaming liquid is poured into a glass mold mainly composed of a glass mold and a resin gasket or tape, and is cured mainly by heat.

The heating condition is such that the temperature is gradually raised from a low temperature to a high temperature in a temperature range of about 0 to 200 ° C., and the heating is completed in about 1 to 100 hours. When a radiation polymerizable monomer is used as the other monomer, radiation irradiation may be used in combination. When irradiating radiation, ultraviolet rays of 400 nm or less are mainly used. Irradiation conditions of ultraviolet rays are approximately 1 to 1000 mJ.
In many cases, irradiation is carried out at an intensity of 1 / sec to 7200 sec. In some cases, cooling is performed before irradiation or irradiation is performed in several times for the purpose of heat removal or obtaining an optically uniform molded product. There is also.

The polythiol used as a monomer for the urethane-based transparent resin, transparent optical material and plastic lens of the present invention is an organic compound having two or more mercapto groups in a molecule, and examples thereof include the following compounds. Can be For example, pentaerythritol poly (3-mercaptopropionate), pentaerythritol poly (thioglycolate), 4- (mercaptomethyl)-
3,6-dithiaoctane-1,8-dithiol, 4,8
-Bis (mercaptomethyl) -3,6,9-trithiaundecane-1,11-dithiol, 2,5-bis (mercaptomethyl) -1,4-dithiane, trithioglycerin, 1,1,3,3 -Tetrakis (mercaptomethyl)
-2-thiapropane and the like. In addition, this invention is not limited only to these listed compounds.

As other monomers added as required, for example, polyiso (thio) cyanates other than the formula (1), (meth) acrylic compounds, allyl or vinyl compounds, (thio) epoxy compounds and the like can be mentioned.

Examples of the polyiso (thio) cyanate other than the formula (1) include m-xylylenediiso (thio) cyanate, α, α, α ′, α′-tetramethyl-m-xylylenediiso (thio) Cyanate, 1,3-bis (iso (thio) cyanatomethyl) cyclohexane, isophoronediiso (thio) cyanate, bis (4-iso (thio)
Cyanatocyclohexyl) methane, hexamethylenediiso (thio) cyanate, trimethylhexamethylenediiso (thio) cyanate, bis (isocyanatomethyl) norbornane, bis (isocyanatomethylthio) methane and the like. In addition, this invention is not limited only to these listed compounds.

As the (meth) acrylic compound, for example, ethylene glycol di [(meth) acrylate],
Diethylene glycol di [(meth) acrylate], butanediol di [(meth) acrylate], neopentyl glycol di [(meth) acrylate], trimethylolpropane tris [(meth) acrylate], pentaerythritol tris [(meth) acrylate] Pentaerythritol tetrakis [(meth) acrylate], dipentaerythritol hexa [(meth) acrylate], 2,2-bis [(meth) acryloylethoxyethoxyphenyl] propane, 2,2-bis [(meth) acryloylethoxyphenyl ] Propane, bis [(meth) acryloylethoxyethoxyphenyl] methane, bis [(meth) acryloylethoxyphenyl]
Methane, bis [(meth) acryloylmethyl] tricyclodecane, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, ethanedithioldi [(meth) acrylate] , 3-thiaheptane-1,5-dithioldi [(meth) acrylate], 2,5-bis [(meth) acryloylthiomethyl] -1,4-dithiane and the like. In addition, this invention is not limited only to these listed compounds.

Examples of the allyl or vinyl compound include, for example, diethylene glycol bis (allyl carbonate), diallyl sulfide, styrene, isopropenylbenzene, divinylbenzene, vinylcyclohexene oxide, diisopropenylbenzene, 3-isopropenyl-α, α-dimethyl Benzyl isocyanate and the like. In addition, this invention is not limited only to these listed compounds.

Examples of (thio) epoxy compounds include bisphenol A diglycidyl ether, bisphenol A bis [3-glycidyloxy-2-hydroxy-1-propyl ether], 3,4-epoxycyclohexylcarboxylic acid 3,4- Epoxycyclohexylmethyl ester, 1,4-butanedicarboxylic acid di3,4-epoxycyclohexylmethyl ester, vinylcyclohexene dioxide, diglycidyl sulfide, bis (epithiopropyl) sulfide, bis (epithiopropyl)
Disulfide and the like. In addition, this invention is not limited only to these listed compounds.

In the production of the transparent resin, transparent optical material and plastic lens of the present invention, if necessary, a heat catalyst, a photocatalyst, an ultraviolet absorber, an internal mold release agent, an antioxidant, a polymerization inhibitor, an oil-soluble agent Known additives such as dyes, fillers and plasticizers may be added.

Further, the obtained transparent resin, transparent optical material,
In addition, plastic lenses have surface polishing, antistatic treatment, hard coating, etc. to improve anti-reflection, high hardness, abrasion resistance, chemical resistance, anti-fog, or fashion, if necessary. Physical or chemical treatment such as treatment, anti-reflection coating treatment, and light control treatment can be performed.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below by way of examples and comparative examples using a plastic lens as an example. The refractive index of the obtained plastic lens was measured at 20 ° C. using a Pulfrich refractometer.

Example 1 76.1 g (1.0 mol) of carbon disulfide, 51.7 g of water,
A mixture of 81.6 g (1.0 mol) of 49 wt% aqueous NaOH was mixed with 77.1 g of bis (aminomethyl) norbornane.
(0.5 mol) at 20-30 ° C. over 1 hour,
Aged at 70-80 ° C for 1 hour. To this reaction solution, add water 10
After adding 0 ml and 200 ml of toluene, 100.0 g (1.05 mol) of methyl chloroformate was added to 40 to
The mixture was added dropwise at 55 ° C over 1 hour, and aged at 40 to 50 ° C for 1 hour. The lower aqueous layer was separated and discarded, and the obtained organic layer was dried over anhydrous magnesium sulfate and kept at 90 to 100 ° C. for 2 hours to complete the decomposition. The obtained reaction solution was desolvated under reduced pressure, distillation under reduced pressure was started, and the temperature was reduced to 210 to 220 ° C./5 t.
orr (0.7 kPa) fraction was separated by GC.
35.5 g of bis (isothiocyanatomethyl) norbornane having a purity of 97.2 area% was obtained. The identification data of this fraction is described below. Elemental analysis, Table 1, mass spectrum, FIG. 1, IR spectrum, FIG. 2, NMR spectra, Figure 3 a ¹ H-NMR, ^{1 3} 4 a C-NMR
It described in.

[0026]

[Table 1] Table 1 Elemental analysis

Example 2 bis (isothiocyanatomethyl) norbornane 56.5
g (0.237 mol), dibutyltin dichloride 500
mg (5000 ppm), 2- (2-hydroxy-5-
t-octylphenyl) benzotriazole 50 mg
(500 ppm), di (1,4,7-trimethyl-3,
6,9-Trioxatridecyl) phosphoric acid 150 mg (15 mg
00 ppm), 4,8-bis (mercaptomethyl) -3,6,9-trithiaundecane-1,1
43.5 g (0.119 mol) of 1-dithiol was added to mix and homogenize, and mixed and defoamed under reduced pressure. After the defoaming was completed, the defoaming liquid was poured into a molding mold prepared in advance, and was cured by heating from room temperature to 120 ° C. over 20 hours. The obtained plastic lens was transparent and had a refractive index of 1.695 and a specific gravity of 1.33. The results are shown in Table 2.

Comparative Examples 1 to 3 Instead of bis (isothiocyanatomethyl) norbornane, a general alicyclic polyisocyanate was used, and the amount of dibutyltin dichloride as a catalyst was adjusted to 400 pp.
m, and a plastic lens was manufactured in the same manner as in Example 1. The results are shown in Table 2.

[0029]

[Table 2]

[0030]

According to the present invention, it is possible to provide a novel polyisocyanate, a transparent resin having an improved refractive index, a transparent optical material, and a plastic lens.

[Brief description of the drawings]

FIG. 1 Identification data of Example 1: IR spectrum

FIG. 2 Identification data of Example 1: mass spectrum

FIG. 3 Identification data of Example 1: NMR spectrum ¹
H-NMR spectrum

FIG. 4 Identification data of Example 1: NMR spectrum ¹³
C-NMR spectrum

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshinobu Kanemura 30 Asamuta-cho, Omuta-shi, Fukuoka F-term (reference) 4H006 AA01 AB46 AB84 4J034 BA02 CA04 CA32 CB03 CB04 CB05 CB07 CC03 CC08 CC09 CC12 CC45 CC52 CC62 CC65 DK02 DK03 DK05 DK06 DK08 HA01 HA07 HA11 HB02 HC03 HC12 HC17 HC22 HC45 HC46 HC52 HC54 HC64 HC71 HC73

Claims (4)

[Claims] 1. A compound represented by the following formula (1): A polyisothiocyanate represented by 2. A urethane transparent resin obtained by reacting a polyisothiocyanate represented by the formula (1) with a polythiol. 3. A urethane-based transparent optical material obtained by reacting a polyisothiocyanate represented by the formula (1) with a polythiol. 4. A urethane-based plastic lens obtained by reacting a polyisothiocyanate represented by the formula (1) with a polythiol.