JP2006321950A - Optical polyurethane resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical polyurethane resin which satisfies optical characteristics at practical levels and has excellent mechanical properties such as impact resistance. <P>SOLUTION: This optical polyurethane resin is characterized by reacting a polyisocyanate component comprising at least one non-aromatic polyisocyanate selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, araliphatic polyisocyanates and their modified products with a polylol component comprising an aromatic ring-containing polyol having a phenolic hydroxyl group content of ≤0.5 mol. %. This optical polyurethane resin has a pot life, when cast and then molded in a mold, and therefore gives molded articles having excellent optical characteristics such as transparency, color tones and striae and excellent mechanical physical properties such as impact resistance. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical polyurethane resin, and more particularly to an optical polyurethane resin suitable for optical lenses, optical components, and the like.

Cast polyurethane molded by the prepolymer method or the one-shot method is excellent in mechanical properties such as wear resistance and impact resistance, and is used in various industrial applications as industrial products such as rolls and belts.
On the other hand, in optical applications such as optical lenses and optical parts, in recent years, not only excellent optical properties but also mechanical properties excellent in impact resistance and the like have been demanded. Therefore, cast polyurethane is used for optical applications. Is being considered.

For example, an optical component containing, as essential components, a prepolymer obtained by reacting an aliphatic cyclic polyisocyanate having two or more isocyanate groups, a polyol having two or more hydroxyl groups, an internal release agent, and a decolorized aromatic diamine. It has been proposed to mold an impact-resistant lens from a polyurethane resin composition for lens molding (see, for example, Patent Document 1).
JP 2003-301025 A

However, in the polyurethane resin composition for molding an optical lens described in Patent Document 1, the optical properties such as color tone and striae cannot satisfy the requirements of practical level, and further improvement of the optical properties is achieved. In addition, development of an optical polyurethane resin having excellent mechanical properties is eagerly desired.
An object of the present invention is to provide an optical polyurethane resin that satisfies optical properties at a practical level and is excellent in mechanical properties such as impact resistance.

  In order to achieve the above object, the optical polyurethane resin of the present invention comprises at least one non-aromatic compound selected from the group consisting of aliphatic polyisocyanates, alicyclic polyisocyanates, araliphatic polyisocyanates, and modified products thereof. By reacting a polyisocyanate component containing an aromatic polyisocyanate with a polyol component containing an aromatic ring-containing polyol having a phenolic hydroxyl group defined in JIS K0102-1986 (28. phenols) of 100 ppm or less in terms of cresol. It is characterized by being obtained.

In the optical polyurethane resin of the present invention, it is preferable that the aromatic ring-containing polyol does not substantially contain a phenolic hydroxyl group.
In the optical polyurethane resin of the present invention, the aromatic ring-containing polyol is obtained by a reaction between an aromatic ring-containing initiator and an oxygen atom-containing compound that is polymerized with a reaction of the aromatic ring-containing initiator as an initiation reaction. Is preferred.

In the optical polyurethane resin of the present invention, it is preferable that the polyol component further contains a macropolyol.
The optical polyurethane resin of the present invention preferably has a haze value of 0.5 or less.

  The optical polyurethane resin of the present invention has a long pot life during molding. Therefore, it has excellent optical properties such as transparency, color tone and striae, and excellent mechanical properties such as impact resistance. Therefore, for example, it can be suitably used for optical lenses such as transparent lenses, sunglasses lenses, and polarizing lenses, and optical parts such as protective glasses, hoods, protective shields, automobile security parts, and lighting parts.

The optical polyurethane resin of the present invention can be obtained by reacting a polyisocyanate component containing a non-aromatic polyisocyanate and a polyol component containing an aromatic ring-containing polyol.
In the present invention, the non-aromatic polyisocyanate as the polyisocyanate component is a polyisocyanate other than the aromatic polyisocyanate, and is an aliphatic polyisocyanate, an alicyclic polyisocyanate, an araliphatic polyisocyanate, or a modified product thereof. Selected.

  Examples of the aliphatic polyisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1, , 3-butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanate methyl caproate and the like.

Examples of the alicyclic polyisocyanate include 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (IPDI), 4,4'-methylenebis (cyclohexyl isocyanate) (H ₁₂ MDI), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 1,4-bis (isocyanatomethyl) cyclohexane (H ₆ XDI) And alicyclic diisocyanates such as bis (isocyanatomethyl) norbornane (NBDI).

Examples of the araliphatic polyisocyanate include araliphatic diisocyanates such as 1,3- or 1,4-xylylene diisocyanate (XDI) or a mixture thereof, and tetramethylxylylene diisocyanate (TMXDI).
Examples of the modified non-aromatic polyisocyanate include non-aromatic diisocyanate derivatives such as dimers, trimers, biurets, allophanates, carbodiimides, uretdiones, and oxadiazine triones of the above-mentioned non-aromatic diisocyanates. Further, for example, by reacting the above-mentioned non-aromatic diisocyanate or its derivative with a low molecular weight polyol at an equivalent ratio in which the isocyanate group of the non-aromatic diisocyanate or its derivative is in excess of the hydroxyl group of the low molecular weight polyol. Examples of the resulting polyol adducts are given.

  Examples of the low molecular weight polyol include ethylene glycol, propanediol, 1,4-butylene glycol, 1,3-butylene glycol, 1,2-butylene glycol, 1,6-hexanediol, neopentyl glycol, alkane ( C7-C22) diol, diethylene glycol, triethylene glycol, dipropylene glycol, cyclohexanedimethanol, alkane-1,2-diol (C17-C20), bisphenol A, hydrogenated bisphenol A, 1,4-dihydroxy-2-butene , 2,6-dimethyl-1-octene-3,8-diol, bishydroxyethoxybenzene, xylene glycol, bishydroxyethylene terephthalate and other low molecular weight diols such as glycerin, 2-methyl-2- Droxymethyl-1,3-propanediol, 2,4-dihydroxy-3-hydroxymethylpentane, 1,2,6-hexanetriol, 1,1,1-tris (hydroxymethyl) propane (TMP), 2,2- Low molecular weight triols such as bis (hydroxymethyl) -3-butanol and other aliphatic triols (C8-C24) such as tetramethylolmethane, pentaerythritol, D-sorbitol, xylitol, D-mannitol, D-mann And low molecular weight polyols having 4 or more hydroxyl groups such as knit.

These non-aromatic polyisocyanates can be used alone or in combination of two or more. Of these, HDI, H ₁₂ MDI, H ₆ XDI, NBDI, XDI, TMXDI, HDI trimer, HDI biuret, and HDI-TMP adduct are preferable.
Further, the polyisocyanate component is substantially composed of the non-aromatic polyisocyanate described above.

  In the present invention, the aromatic ring-containing polyol as a polyol component is a polyol having an aromatic ring in the molecular chain and having two or more hydroxyl groups at the molecular ends, and is JIS K0102-1986 (28. Phenols). The phenolic hydroxyl group defined in) is 100 ppm or less in terms of cresol, preferably 50 ppm or less, more preferably 30 ppm or less, and particularly preferably a polyol substantially free of phenolic hydroxyl groups. When the phenolic hydroxyl group exceeds the above ratio, the resin may be colored during curing when cured at a high temperature of 100 ° C. or higher. If the phenolic hydroxyl group is less than the above-mentioned ratio, even if cured at a high temperature of 100 ° C. or higher, coloring of the resin during curing is remarkably suppressed, and a cured product that does not generate color or does not substantially color is obtained. Can do.

Such an aromatic ring-containing polyol can be obtained, for example, by a reaction between an aromatic ring-containing initiator and an oxygen atom-containing compound that is polymerized with the reaction of the aromatic ring-containing initiator as an initiation reaction.
Examples of the aromatic ring-containing initiator include a phenol compound having a phenolic hydroxyl group and a xylene compound having a benzyl alcoholic hydroxyl group.

  Examples of phenolic compounds include 4,4′-isopropylidenediphenol (common name: bisphenol A) and 4,4′-isopropylidene-bis (2,6-dibromophenol) (common name: tetrabromobisphenol A). ), 4,4 ′-(hexafluoroisopropylidene) bisphenol (common name: bisphenol AF), 4,4 ′-(1-phenylethylidene) bisphenol (common name: bisphenol AP), 4,4 ′-(1- Methylpropylidene) bisphenol (common name: bisphenol B), bis (4-hydroxyphenyl) -2,2'-dichloroethylene (common name: bisphenol C), 1,1 '-(4-hydroxyphenyl) ethane (common name) : Bisphenol E), 4,4'-methylene bisphenol (common name: bisphenol) F), bis (4-hydroxy-3,5-dimethylphenyl) methane (common name: tetramethylbisphenol F), 4,4 '-(1,3-ferene isopropylidene) bisphenol (common name: bisphenol M) ), 4,4 '-(1,4-ferenediisopropylidene) bisphenol (common name: bisphenol P) 4,4'-dihydroxydiphenyl sulfone (common name: bisphenol S), 4,4'-cyclohexylidene Examples thereof include bisphenols such as bisphenol (common name: bisphenol Z) and 4,4′-dihydroxybiphenyl.

Examples of phenolic compounds include dihydroxybenzenes such as hydroquinone, resorcin, catechol, and methyl t-butylhydroquinone, and polyhydroxybenzenes such as trihydroxybenzenes such as pyrogallol and phloroglucin.
Examples of xylene compounds include xylene glycol.

Examples of the oxygen atom-containing compound include alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide.
The reaction between the aromatic ring-containing initiator and the oxygen atom-containing compound may be performed in accordance with a known method. For example, by reacting a bisphenol with an alkylene oxide to cause ring-opening polymerization of the alkylene oxide, A ring-containing polyol can be obtained.

In this reaction, the oxygen atom-containing compound is added in an amount of, for example, 2.0 to 20 mol, preferably 2.1 to 10 mol, with respect to 1 mol of the aromatic ring-containing initiator.
The aromatic ring-containing polyol thus obtained has a number average molecular weight of, for example, 150 to 2500, preferably 200 to 1500, and a hydroxyl group equivalent of, for example, 95 to 1200, preferably 100 to 700. .

  Among these, Preferably, an alkylene oxide adduct of bisphenols in which alkylene oxides are added to bisphenols, and more preferably, bisphenol A ethylene oxide and / or propylene oxide added to bisphenol A and And / or a propylene oxide adduct.

  Moreover, as an aromatic ring containing polyol, the bisphenol type compound shown by following General formula (1) can also be mentioned.

(Wherein X1 represents a carbon-carbon bond, a divalent hydrocarbon which may contain a C1-30 halogen atom, dihalovinylidene or sulfonyl. X2 represents a hydrogen atom, a C1-4 alkyl group or Y represents a halogen atom, and Y represents a monovalent hydrocarbon group which may contain C1-100 oxygen.)
Examples of the C1-30 divalent hydrocarbon represented by X1 include methylene, methylmethylene, dimethylmethylene, methylethylmethylene, methylphenylmethylene, ditrifluoromethylmethylene, phenylenediisopropylidene, cyclohexylidene and the like. It is done.

Examples of the dihalovinylidene represented by X1 include dichlorovinylidene.
Examples of the C1-4 alkyl group represented by X2 include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl and the like.
Examples of the halogen atom represented by X2 include fluorine, chlorine, bromine and iodine.

Examples of the C1-100 monovalent hydrocarbon group represented by Y include polyoxyalkylenes such as polyoxyethylene, polyoxypropylene, poly (oxyethylene / oxypropylene), and polyoxybutylene.
The general formula (1) includes the above-described alkylene oxide adduct of bisphenols and is a higher-level conceptual compound of the alkylene oxide adduct of bisphenols.

  Such aromatic ring-containing polyols are commercially available. For example, bisol 2PN (manufactured by Toho Chemical Co., Ltd., bisphenol A-propylene oxide 2.2 mol adduct), Adeka polyol BPX-33 (manufactured by Asahi Denka Kogyo Co., Ltd.) Bisphenol A-propylene oxide 6 mol adduct), Newpol BPE-20T (manufactured by Sanyo Chemical Industries, bisphenol A-ethylene oxide 2.1 mol adduct), Newpol BP-23T (manufactured by Sanyo Chemical Industries, bisphenol) A-propylene oxide 2.3 mol adduct), Newpol BP-2P (manufactured by Sanyo Chemical Industries, bisphenol A-propylene oxide 2.0 mol adduct), SEO-2 (manufactured by Nikka Chemical Co., Ltd., bisphenol S-) Ethylene oxide 2-mol adduct) and the like.

The aromatic ring-containing polyol can be used alone or in combination of two or more.
In the present invention, the polyol component may further contain a macropolyol.
Examples of the macropolyol include polyether polyol, polyester polyol, polycarbonate polyol, acrylic polyol, epoxy polyol, natural oil polyol, silicon polyol, fluorine polyol, and polyolefin polyol.

  Examples of the polyether polyol include polyethylene glycol, polypropylene glycol and / or polyethylene polypropylene glycol (polyethylene glycol, and / or polyethylene polypropylene glycol (obtained by addition reaction of alkylene oxide such as ethylene oxide and / or propylene oxide) using the above-described low molecular weight polyol as an initiator. Random or block copolymer). Examples thereof include polytetramethylene ether glycol obtained by ring-opening polymerization of tetrahydrofuran.

  Examples of the polyester polyol include one or more of the above-described low molecular weight polyols and, for example, oxalic acid, malonic acid, succinic acid, methyl succinic acid, glutaric acid, adipic acid, 1,1-dimethyl-1,3. -Dicarboxypropane, 3-methyl-3-ethylglutaric acid, azelaic acid, sebacic acid, other aliphatic dicarboxylic acids (C11-C13), hydrogenated dimer acid, maleic acid, fumaric acid, itaconic acid, orthophthalic acid , Carboxylic acids such as isophthalic acid, terephthalic acid, toluene dicarboxylic acid, dimer acid and het acid, and acid anhydrides derived from these carboxylic acids such as oxalic anhydride, succinic anhydride, maleic anhydride, Phthalic anhydride, 2-alkyl (C12-C18) succinic anhydride, tetrahydrophthalic anhydride , Trimellitic anhydride, and further, an acid halide derived from such these carboxylic acids, such as oxalic acid dichloride, adipic acid dichloride, and polyester polyols obtained by the reaction of such sebacic acid dichloride. Also, for example, lactone-based polyesters such as polycaprolactone polyols and polyvalerolactone polyols obtained by ring-opening polymerization of lactones such as ε-caprolactone and γ-valerolactone using the above low molecular weight polyol as an initiator. A polyol etc. are mentioned.

Examples of the polycarbonate polyol include polycarbonate polyols obtained by ring-opening polymerization of carbonates such as ethylene carbonate and dimethyl carbonate using the above-described low molecular weight polyol as an initiator.
Examples of the acrylic polyol include a copolymer obtained by copolymerizing a polymerizable monomer having one or more hydroxyl groups in the molecule and another monomer copolymerizable therewith. . Examples of the polymerizable monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, 2,2-dihydroxymethylbutyl (meth) acrylate, and polyhydroxy. Examples thereof include alkyl maleates and polyhydroxyalkyl fumarate. Moreover, as another monomer copolymerizable with these, for example, (meth) acrylic acid, alkyl (meth) acrylate (C1 to C12), maleic acid, alkyl maleate, fumaric acid, alkyl fumarate, Itaconic acid, alkyl itaconate, styrene, α-methylstyrene, vinyl acetate, (meth) acrylonitrile, 3- (2-isocyanato-2-propyl) -α-methylstyrene, trimethylolpropane tri (meth) acrylate, pentaerythritol Examples include tetra (meth) acrylate. The acrylic polyol can be obtained by copolymerizing these monomers in the presence of an appropriate solvent and a polymerization initiator.

Examples of the epoxy polyol include an epoxy polyol obtained by reacting the above-described low molecular weight polyol with a polyfunctional halohydrin such as epichlorohydrin or β-methylepichlorohydrin.
Examples of the natural oil polyol include hydroxyl group-containing natural oils such as castor oil and coconut oil.

As the silicon polyol, for example, a copolymer obtained by using a vinyl group-containing silicon compound such as γ-methacryloxypropyltrimethoxysilane as a copolymerizable monomer in the copolymerization of the acrylic polyol described above. Examples thereof include polymers and terminal alcohol-modified polydimethylsiloxane.
As the fluorine polyol, for example, a copolymer obtained by using a vinyl group-containing fluorine compound, for example, tetrafluoroethylene, chlorotrifluoroethylene, or the like as a copolymerizable monomer in the copolymerization of the acrylic polyol described above. Examples include coalescence.

Examples of the polyolefin polyol include polybutadiene polyol, partially saponified ethylene-vinyl acetate copolymer, and the like.
These macropolyols have a number average molecular weight of, for example, 200 to 5000, preferably 300 to 2000, and a hydroxyl group equivalent of, for example, 50 to 2500, preferably 150 to 1000.

  These macropolyols can be used alone or in combination of two or more. Of these, polyether polyol, polyester polyol, and polycarbonate polyol are preferable. More preferably, examples of the polyether polyol include polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. Examples of the polyester polyol include adipate polyester diol and polycaprolactone diol. Examples of the polycarbonate polyol include polycarbonate diol.

When the polyol component contains the macropolyol, the blending ratio of the macropolyol is, for example, 1000 parts by weight or less, preferably 500 parts by weight or less with respect to 100 parts by weight of the aromatic ring-containing polyol.
In the present invention, the polyol component may further contain the above-described low molecular weight polyol depending on the purpose and application. The low molecular weight polyol is preferably a low molecular weight triol such as glycerin, TMP, or pentaerythritol, or a low molecular weight tetraol from the viewpoint of improving the hardness and chemical resistance of the resulting optical polyurethane resin.

When the low molecular weight polyol is included in the polyol component, the blending ratio of the low molecular weight polyol is, for example, 500 parts by weight or less, preferably 300 parts by weight or less with respect to 100 parts by weight of the aromatic ring-containing polyol.
And the optical polyurethane resin of this invention can be obtained by making the above-mentioned polyisocyanate component and a polyol component react. In order to react the polyisocyanate component and the polyol component, for example, a casting polyurethane molding method such as a one-shot method or a prepolymer method can be used.

  In the one-shot method, for example, the above-mentioned polyisocyanate component and polyol component have an equivalent ratio of the isocyanate group in the polyisocyanate component to the hydroxyl group in the polyol component (NCO / OH equivalent ratio) of, for example, 0.5 to 2 0.0, preferably formulated (mixed) so as to be 0.75 to 1.25, and then poured into a mold, for example, at room temperature to 150 ° C., preferably at room temperature to 120 ° C., for example, 10 The curing reaction is carried out for minutes to 72 hours, preferably 4 to 24 hours. The curing temperature may be a constant temperature or may be raised and cooled stepwise.

In this curing reaction, the polyisocyanate component and / or the polyol component are preferably heated and mixed after being reduced in viscosity, and then defoamed as necessary, followed by preheating. Inject into mold.
And after inject | pouring into a shaping | molding die and making it react, if it demolds, the polyurethane resin for optics shape | molded by the desired shape can be obtained. In addition, after demolding, as needed, it can also be heat-formed within about 7 days at room temperature.

  The prepolymer method is used when the polyol component contains a macropolyol. For example, the isocyanate component and the macropolyol are first reacted to synthesize an isocyanate group-terminated prepolymer having an isocyanate group at the molecular end. . Next, the obtained isocyanate group-terminated prepolymer is reacted with an aromatic ring-containing polyol and, if necessary, a low molecular weight polyol to cause a curing reaction.

  In order to synthesize an isocyanate group-terminated prepolymer, a polyisocyanate component and a macropolyol have an equivalent ratio (NCO / OH equivalent ratio) of an isocyanate group in the polyisocyanate component to a hydroxyl group in the macropolyol of, for example, 1.1. To 20 and preferably 1.5 to 10 in a reaction vessel, for example, room temperature to 150 ° C., preferably 50 to 120 ° C., for example 0.5 to 18 The reaction is performed for a time, preferably 2 to 10 hours. In this reaction, a known urethanization catalyst such as an organic metal type or an amine type may be added if necessary, and after the reaction is completed, if necessary, an unreacted non-aromatic catalyst. You may remove polyisocyanate by well-known means, such as distillation and extraction, for example.

The obtained isocyanate group-terminated prepolymer has an isocyanate equivalent of, for example, 80 to 2000, preferably 100 to 1000, and the viscosity of the prepolymer is, for example, 10 to 10 It is 10,000 mPa · s, preferably 10 to 5,000 mPa · s.
Next, in order to react the obtained isocyanate group-terminated prepolymer with an aromatic ring-containing polyol and, if necessary, a low molecular weight polyol, the isocyanate group-terminated prepolymer, the aromatic ring-containing polyol and, if necessary, a low molecular weight polyol, The equivalent ratio (NCO / OH equivalent ratio) of the isocyanate group of the isocyanate group-terminated prepolymer to the total hydroxyl groups of the ring-containing polyol and, if necessary, the low molecular weight polyol is, for example, 0.5 to 2.0. Formulated (mixed) to be 75 to 1.25, poured into a mold, for example, room temperature to 150 ° C., preferably room temperature to 120 ° C., for example, 5 minutes to 72 hours, preferably 1 Allow to cure for ~ 24 hours.

In this curing reaction, an isocyanate group-terminated prepolymer and / or an aromatic ring-containing polyol and, if necessary, a low-molecular-weight polyol are preferably mixed by heating to lower the viscosity, and then if necessary. After defoaming, it is poured into a preheated mold.
And after inject | pouring into a shaping | molding die and making it cure-react, if it demolds, the optical polyurethane resin shape | molded by the desired shape can be obtained. In addition, after demolding, as needed, it can also be heat-formed within about 7 days at room temperature.

The optical polyurethane resin thus obtained has a long pot life at the time of molding after injection of the mold, so that it is excellent in optical properties such as transparency, color tone and striae, and in addition to conventional thiol resins. Even compared, it is excellent in mechanical properties such as impact resistance.
More specifically, this optical polyurethane resin has a hardness of 30 to 100 in the hardness (HSD) of JIS K7312-1996, and has excellent impact resistance by a falling ball test. Can be evaluated.

Moreover, this optical polyurethane resin has a haze value of 0.5 or less, preferably 0.3 or less in terms of optical characteristics, has a colorless color tone, and can visually confirm striae. Can not.
Therefore, this optical polyurethane resin satisfies optical characteristics at a practical level and is excellent in mechanical properties such as impact resistance. For example, an optical lens such as a transparent lens, a sunglasses lens, a polarizing lens, For example, it can be suitably used for optical parts such as protective glasses, hoods, protective shields, automobile security parts, and lighting parts.

Such optical polyurethane resins include, for example, internal mold release agents, plasticizers, antifoaming agents, leveling agents, matting agents, flame retardants, thixotropic agents, tackifiers, Known additives such as a sticking agent, a lubricant, an antistatic agent, a surfactant, a reaction retarding agent, a dehydrating agent, an antioxidant, an ultraviolet absorber, a hydrolysis inhibitor and a weathering stabilizer can be appropriately blended.
For example, when an internal mold release agent is blended, examples of the internal mold release agent include a fatty acid ester type, a phosphate ester type, and an alkyl phosphate type, and specifically, Zelec NE (Stepan). Etc.) are used. By blending such an internal mold release agent, the mold can be easily released from the mold and a cured product having a small haze value can be obtained.

The present invention will be specifically described below with reference to examples and comparative examples. In the examples, “%” and “parts” are based on weight.
Preparation Example 1 (Preparation of isocyanate group-terminated prepolymer A)
950 parts of polytetramethylene ether glycol having a number average molecular weight of 661 (manufactured by Hodogaya Chemical Co., Ltd., PTG-650SN) is added to a 2 L 5-diameter round flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a Dimroth, Was stirred for 2 hours at 110 ° C. while bubbling (flow rate: 10 L / min), and then dehydrated. Thereafter, 1050 g of H ₁₂ MDI (manufactured by Sumitomo Bayer Urethane, Desmodur W) was added and reacted at 110 ° C. for 4 hours to obtain an isocyanate group-terminated prepolymer A.

The obtained isocyanate group-terminated prepolymer A was colorless and transparent, and had an isocyanate equivalent of 395, a viscosity of 12000 mPa · s at 25 ° C., and a viscosity of 1200 mPa · s at 60 ° C.
Preparation Example 2 (Preparation of isocyanate group-terminated prepolymer B)
To a 2 L 5-diameter round flask equipped with a thermometer, stirrer, nitrogen inlet tube, and Dimroth, polyethylene adipate having a number average molecular weight of 550 (polyester polyol obtained by reaction of adipic acid and ethylene glycol, manufactured by Mitsui Takeda Chemical Co., Ltd., 893 parts of Takelac U-550) was added, and the mixture was stirred at 110 ° C. for 2 hours while bubbling nitrogen (flow rate: 10 L / min), and then dehydrated. Thereafter, 1107 g of H ₁₂ MDI (manufactured by Sumitomo Bayer Urethane, Desmodur W) was added and reacted at 110 ° C. for 3 hours to obtain an isocyanate group-terminated prepolymer B.

The obtained isocyanate group-terminated prepolymer B was colorless and transparent, and had an isocyanate equivalent of 387, a viscosity of 139000 mPa · s at 25 ° C., and a viscosity of 3200 mPa · s at 60 ° C.
Preparation Example 3 (Preparation of non-aromatic polyisocyanate A)
HDI trimer (Takenate manufactured by Mitsui Takeda Chemical Co., Ltd., D-170HN) was used as non-aromatic polyisocyanate A as it was. This non-aromatic polyisocyanate A was colorless and transparent, and had an isocyanate equivalent of 186, a viscosity of 560 mPa · s at 25 ° C., and a viscosity of 80 mPa · s at 60 ° C.

Preparation Example 4 (Preparation of aromatic ring-containing polyol A)
A bisphenol A-propylene oxide 2.2 mol adduct (manufactured by Toho Chemical Co., Ltd., bisol 2PN, phenolic hydroxyl group 47 ppm) was stirred at 110 ° C. for 2 hours while bubbling nitrogen (flow rate 10 L / min), and then dehydrated. As a result, an aromatic ring-containing polyol A was obtained.
Preparation Example 5 (Preparation of aromatic ring-containing polyol B)
After stirring bisphenol A-propylene oxide 6 mol adduct (Asahi Denka Kogyo Co., Ltd., Adekapolyol BPX-33, phenolic hydroxyl group 30 ppm) at 110 ° C. for 2 hours while bubbling nitrogen (flow rate 10 L / min). Then, dehydration was performed to obtain an aromatic ring-containing polyol B.

Preparation Example 6 (Preparation of aromatic ring-containing polyol C)
Bisphenol A-ethylene oxide 2.1 mol adduct (manufactured by Sanyo Chemical Industries, New Pole BPE-20T, phenolic hydroxyl group 20 ppm) was stirred at 110 ° C. for 2 hours while bubbling nitrogen (flow rate 10 L / min). Then, dehydration was performed to obtain an aromatic ring-containing polyol C.

Preparation Example 7 (Preparation of aromatic ring-containing polyol D)
100 parts of a bisphenol A-propylene oxide 2.3 mol adduct (manufactured by Sanyo Chemical Industries, Newpol BP-23T, phenolic hydroxyl group 30 ppm), 200 parts of the above-mentioned Adekapolyol BPX-33, and 30 parts of trimethylolpropane The mixture was stirred at 110 ° C. for 2 hours while bubbling nitrogen (flow rate: 10 L / min), and then dehydrated to obtain an aromatic ring-containing polyol D.

Preparation Example 8 (Preparation of aromatic ring-containing polyol E)
Bisphenol A-propylene oxide 2.0 mol adduct (manufactured by Sanyo Chemical Industries, New Pole BP-2P, phenolic hydroxyl group 258 ppm) was stirred at 110 ° C. for 2 hours while bubbling nitrogen (flow rate 10 L / min). Then, dehydration was performed to obtain an aromatic ring-containing polyol E.

Preparation Example 9 (Preparation of aromatic ring-free polyol A)
Polypropylene glycol having a number average molecular weight of 400 (manufactured by Mitsui Takeda Chemical Co., Ltd., Diol 400) was stirred for 2 hours at 110 ° C. while bubbling nitrogen (flow rate: 10 L / min), then dehydrated, and no aromatic ring-containing polyol A Got.
Preparation Example 10 (Preparation of aromatic polyamine A)
Purified and lightened 4,4-methylenebis (2-chloroaniline) (ISOCROSS WM manufactured by SHUANGBANG Ind. Co.) was used as aromatic polyamine A as it was.

Preparation Example 11 (Preparation of aromatic polyamine B)
4,4-Methylenebis (2-chloroaniline) (Cuamine MT, manufactured by Ihara Chemical Co., Ltd.), which is widely used for casting polyurethane, was used as aromatic polyamine B as it was.
Preparation Example 12 (Preparation of aromatic polyamine C)
Diethyltoluenediamine (Albemarle, Ethacure 100) was used as aromatic polyamine C as it was.

Preparation Example 13 (Preparation of aromatic polyamine D)
Dimethylthiotoluenediamine (manufactured by Albemarle, Ethacure 300) was used as aromatic polyamine D as it was.
Examples and Comparative Examples In general casting (casting) method, as shown in Table 1, isocyanate group-terminated prepolymer A or B or non-aromatic polyisocyanate A is used as a main agent, and an aromatic ring is contained. The polyols A to E, the aromatic ring-free polyol A, or the aromatic polyamines A to D are used as curing agents, and these main agents and curing agents are formulated as shown in Table 1, and the optical properties of the respective examples and comparative examples. A polyurethane resin was molded.

More specifically, first, the main agent is heated to 60 ° C., the curing agent is heated to 120 ° C., and then the heated main agent and the curing agent are placed in a mixing pot kept at 60 ° C. The NCO / OH equivalent ratio was added at a rate of 1.0 and mixed, and after completion of mixing, defoamed for 30 seconds.
Thereafter, a mold that was applied with an external mold release agent (Die Free GA-6010 manufactured by Daikin Industries Co., Ltd.) and subjected to a mold release treatment so as to wipe off with a waste cloth was preheated to 100 ° C. The mixture of agents was injected. After the injection, the mold was removed after curing at 100 ° C. for 20 hours. As a result, the optical polyurethane resin (cured product) molded in each example and each comparative example was obtained.

Evaluation 1) Mold injection property In the above molding, the ease of injection when the 10 g of the mixture of each example and each comparative example is poured into a preheated mold (clearance 3 mm, 147R) is as follows. Evaluated by. The results are shown in Table 1.
A: Injection was completed within 1 minute without entraining bubbles.
○: Injection was completed within 3 minutes without entraining bubbles.
Δ: Time required for injection was 3 minutes or more.
X: Viscosity was high, and it took time for injection, or bubbles remained in the cured product.
2) Pot life In accordance with JIS K7301-1985 (prepolymer test method), in the above molding, the time until the mixture at 100 ° C. reaches 50,000 mPa · s is defined as the pot life (minutes). It measured about the Example and each comparative example. The results are shown in Table 1.
3) Hardness Based on the hardness test of JIS K7312-1996, the hardness (HSD) was measured for the cured products of each Example and each Comparative Example. The results are shown in Table 1.
4) Transparency (haze value)
About each Example and each comparative example, the hardened | cured material of thickness 3mm was measured with the haze meter (Nippon Denshoku Industries Co., Ltd. make, NDH2000). The results are shown in Table 1.
5) Color tone The color tone of the cured product of each example and each comparative example was visually evaluated. The results are shown in Table 1.
6) Striae About each Example and each comparative example, the hardened | cured material of thickness 3mm was visually observed, and the presence or absence of striae was evaluated according to the following reference | standard. The results are shown in Table 1.
○: The striae could not be confirmed.
Δ: Slight striae were confirmed at the top of the cured product (near the inlet).
▲: Slight striae were confirmed throughout the cured product.
X: Striae was clearly confirmed throughout the cured product.
7) Impact resistance (falling ball test)
A falling ball test was performed in accordance with the technique described in the FDA standard (1972) concerning the impact property of spectacle lenses. That is, after dropping a steel ball from a height of 127 cm with respect to the cured product of each example and each comparative example, the appearance change of the cured product was visually observed and the impact resistance was evaluated according to the following criteria. . The results are shown in Table 1.
A: A 1 Kg steel ball was dropped, but no change in appearance could be confirmed.
Δ: A 500 g steel ball was dropped, but no change in appearance could be confirmed.
X: When a 500 g steel ball was dropped, damage and cracks in the cured product were confirmed on the surface.
XX: Cracking of the cured product was confirmed when a 300 g steel ball was dropped.

Claims (5)

A polyisocyanate component comprising at least one non-aromatic polyisocyanate selected from the group consisting of an aliphatic polyisocyanate, an alicyclic polyisocyanate, an araliphatic polyisocyanate, and a modified product thereof;
A polyol component containing an aromatic ring-containing polyol in which the phenolic hydroxyl group defined in JIS K0102-1986 (28. phenols) is 100 ppm or less in terms of cresol;
An optical polyurethane resin obtained by reacting   The optical polyurethane resin according to claim 1, wherein the aromatic ring-containing polyol does not substantially contain a phenolic hydroxyl group.   3. The aromatic ring-containing polyol is obtained by a reaction between an aromatic ring-containing initiator and an oxygen atom-containing compound that is polymerized with a reaction of the aromatic ring-containing initiator as an initiation reaction. The optical polyurethane resin as described.   The optical polyurethane resin according to claim 1, wherein the polyol component further contains a macropolyol.   The optical polyurethane resin according to claim 1, wherein the haze value is 0.5 or less.