WO1987000535A1

WO1987000535A1 - Photo-setting composition

Info

Publication number: WO1987000535A1
Application number: PCT/JP1985/000407
Authority: WO
Inventors: Satoshi Maruyama; Yoshihisa Yokota; Masataka Goto
Original assignee: Showa Denko Kabushiki Kaisha
Priority date: 1984-01-20
Filing date: 1985-07-19
Publication date: 1987-01-29

Abstract

A photo-setting composition prepared by compounding a polymerizable monomer and/or oligomer with (1) an UV absorber having extinction coefficients of 2,000/M.cm or more at 300 to 350 nm and 1,000/M.cm or less at 360 nm and (2) a photopolymerization initiator having an extinction coefficient of 10/M.cm or less at 390 nm. A colorless, transparent, thick setting product uniformly set to the core can be obtained by irradiating the composition with UV rays from a light source emitting light of 360 to 380 nm.

Description

Willow willow

Photo-curable composition technology field

The present invention is a photocuring method suitable for producing a cured product having a thickness of, for example, 2 mm or more, which is hardly transparent to ultraviolet light having a wavelength of 350 nm or less when irradiated with ultraviolet light and is colorless and transparent to the naked eye. And a method for producing such a cured product. Background technology

Conventionally, in window glass, daylighting materials, eyeglass lenses, etc., from the viewpoint of safety to skin and eyes and prevention of discoloration of stored objects, additives are often added so as not to transmit ultraviolet rays, for example, a large absorption mask in the ultraviolet. An ultraviolet absorber having a torr is included.

In order to incorporate an ultraviolet absorber, a method is used in which a polymer is previously compounded in a polymer when the polymer is molded into a desired shape by injection molding. When a monomer such as methyl rilomer is polymerized into a desired shape by a thermal polymerization method, a method in which an ultraviolet absorbent is dissolved in the monomer in advance has been adopted.

However, in the case of photopolymerizing a photocurable composition in which an ultraviolet absorber is previously blended with a monomer, inconvenience often arises. That is, in the conventional photocurable composition, consideration is given to the number of light-absorbing elements of the ultraviolet absorber and the photopolymerization initiator to be blended. Therefore, if the photocurable composition is irradiated with ultraviolet light during polymerization, the ultraviolet light absorber in the composition absorbs the ultraviolet light, and therefore the light quantity is sufficient to decompose the photopolymerization initiator and generate radicals. Is not obtained and polymerization slows down. In addition, when manufacturing a thick cured product, for example, a cured product having a thickness of 2 mm or more, only the surface is cured and the interior is likely to be insufficiently cured.

In view of the above-mentioned drawbacks of the related art, an object of the present invention is to provide a photocurable composition capable of producing a colorless and transparent cured product that cures uniformly to the inside and does not transmit ultraviolet light, and a photocurable composition thereof. An object of the present invention is to provide a method for producing such a cured product. Disclosure of the invention

In one aspect of the present invention, the polymerizable monomer and the ノ-or oligomer have (1) an extinction coefficient at 300 to 350 nm.

Above 2,000 / Mcm and extinction coefficient at 360 nm of 1,000 / M

• A UV absorber of less than cm and (2) a photopolymerization initiator with an extinction coefficient of at least 50 / M · cm at 360-380 tim and an extinction coefficient at 390 nm of less than 10 / M · cm Provided is a photocurable composition.

In another aspect, the present invention provides a photocurable composition as described above.

Provided is a method for producing a cured product, which comprises irradiating and curing ultraviolet light using a light source having an optical band at 360 to 380ηιη. According to the method of the present invention, curing is uniform to the inside and ultraviolet light is provided. Thick cured product that does not pass through, for example, a cured product with a thickness of 2 mm or more and no UV transmittance, which was difficult to obtain a uniform cured product in the past BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, the term “extinction coefficient” means that the ultraviolet absorber 5 and the photopolymerization initiator are each dissolved in ethanol, the light intensity (I.) before passing through the solution, and the light passing through the solution. Light intensity after

(I), the solution concentration C (M, mol / liter), and the optical path length of the measuring cell, £ (cm), are calculated by the following formula.

£ o _g (I o / I) = s-C-£

10 The reasons for using an ultraviolet absorber and a photopolymerization initiator having specific absorption coefficients in the present invention are as follows. When an ultraviolet absorber or a photopolymerization initiator having an extinction coefficient outside the range of the present invention is used, it is necessary to produce a colorless and transparent cured product which is uniformly cured to 內 parts and does not transmit ultraviolet rays. It is difficult.

15 UV absorber extinction coefficient 300～350N _m is is 2,000 / M. Cm or more on, and is of the absorption coefficient 1, 000 / M · cm or less at 360 nm. When an ultraviolet absorber having a number of light-absorbing particles at 300 to 350 nm of less than 2,000 / i1 * _cm is used, the obtained cured product does not have sufficient ultraviolet shielding property. In addition, when an ultraviolet absorber having an extinction coefficient 20 at 360ηπι exceeding 1,000 / M · cm is used, not only the ultraviolet polymerization is remarkably slowed down, but also only the surface is cured and the interior is insufficiently cured. Has difficulties that remain.

V.

Examples of the ultraviolet absorber having the above-mentioned extinction coefficient include 2,4-dihydroxybenzobenzophenone, 2-hydroxy25shi-4-octadesiloxybenzobenzophenone, and 2-hydroxybenzophenone. — 4—Methoxybenzophenone 1—5—Sulfonic acid, 2—Hydroxy 1—4—Methoxy benzophenone, 2′—Ethylhexyl—2—Cyano—3—Phenylcinname And these may be used as a mixture of two or more.

The compounding amount of the ultraviolet absorber is 0.01 to 1% by weight, preferably 0.02 to 0.5% by weight, based on the total amount of the polymerizable monomer and phenol or oligomer. If the blending amount of the ultraviolet absorber is less than 0.01% by weight, there is almost no ultraviolet absorbing effect. On the other hand, when the blending amount of the ultraviolet absorber exceeds 1% by weight, not only the polymerization becomes remarkably slow, but also the obtained cured product has problems such as opacity and it is difficult to obtain a completely cured product.

The photopolymerization initiator has an extinction coefficient at 360 to 380 nm of 50 / M · cm or more and an extinction coefficient at 390 nm of 10 / M * cm or less. When a photoinitiator having an extinction coefficient of less than 50 / M 未 cm at 360 to 380 nm is used, the polymerization rate is slow, and only the surface is hardened and the inside is hard to harden. When a photopolymerization initiator having an absorption coefficient at 390 nm exceeding 10 / -cm is used, the cured product is colored, and it is difficult to obtain a colorless and transparent cured product.

Examples of the photopolymerization initiator having the above extinction coefficient include benzoinoresimetyl ketal, benzophenone, 4,4'-bisdimethylmethylaminobenzophenone, 2-carboxymethylbenzobenenophen, and benzoin. Benzoin ethyl ether, benzoin sodium, ether, benzoin isobutyl ether, and the like. These photopolymerization initiators can be used as a mixture of two or more. ffl may be.

The compounding amount of the photopolymerization initiator is from 0.01 to 2% by weight, preferably from 0.03 to 0.5% by weight, based on the total amount of the polymerizable monomer and phenolic monomer. If the amount of the initiator is less than 0.01% by weight, the polymerization rate is so slow that a completely cured product cannot be obtained, whereas if the amount of the photoinitiator exceeds 2% by weight, The obtained cured product is colored.

The polymerizable monomer or oligomer used in the present invention may be any colorless and easily polymerizable monomer, but preferably has an absorption coefficient at 390 nm.

10 / M ♦ cm or less. The following are specific examples.

(1) Photopolymerizable bullet monomer

Vinyl esters such as vinyl esters of linear saturated fatty acids having 2 to 5 carbon atoms such as vinyl acetate and vinyl propionate and vinyl esters of branched saturated fatty acids having 8 to 12 carbon atoms; Methyl methacrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, acryl Alkyl groups such as dibutyl, butyl methacrylate, hexyl acrylate, and hexyl methacrylate having 1 to 10 carbon atoms. Alkyl esters of acrylic acid, glycidyl acrylate, glycidyl methacrylate, etc. Esters, diethyl glycol , Diethyl Les Nguri co-one Norejime data click Li rate, door Li methylotrophic over Lubronitol triacrylate, Trimethylol reprorate, Pentaerythritol Tetracreterate Pentaerythritol Tetramethacrylate, Dipentaeryte Acrylic acid of straight-chain or branched alcohol with 16 to 16 carbon atoms, such as hexyl acrylate and dipentaerythritol Or acrylates or methacrylates such as methacrylate, etc .; aromatic butyl hydrocarbons such as styrene, alkyl styrene, dibutylbenzene; chloronostyrene, chlorolac Chlorobutyl compounds such as ester acrylate; Fluoro π styrene, Fluoroalkyl acrylate, Fluoroleate Yo I Do 舍Fu Mmoto Bulle compounds of Rekinore; and mixtures thereof and the like are used.

(2) Monomers capable of photoaddition reaction

Refers to the combination of an unsaturated compound that generates ^ -polymer in a photoaddition reaction and mercaptan. Examples of the unsaturated compound include, in addition to the above-mentioned vinyl-based monomer, polyvalent aryl compounds such as divinyl phthalate and trilinoleic acid cyanate; diarydenpentapentalysate; Compounds having at least two cycloacetal groups in one molecule, such as litol, are used. As the mercaptan, a polyvalent thiol such as trimethylol bronitol trithiopropionate, pentaerythritol tetrathioglycolate, or dipentaerythritol hexatiodalicholate is used. The mixing ratio of the unsaturated compound to mercaptan is equivalent ratio of 3: 7 to 7: 3, preferably 4: 6 to 6: 4. A) Oligo Gomer ''

Photocurable oligomers having a molecular weight of 200-3000 are used, and are typically epoxy acrylate, epoxy methacrylate, polyester acrylate, Polyester methacrylate, polyether acrylate, polyether methacrylate, urethane ♦ acrylate, urethane meta Crylate, Silicone's Crylate, Silicone.metarate, etc.

Of these monomers and oligomers, the monomer capable of photoaddition reaction ( ² ) is preferable, and particularly, a compound (A) having at least two cycloacetal groups in one molecule. ), A mixture of a polyvalent thiol (B) and an acrylate or a methacrylate (C) is preferred because it gives a cured product having excellent transparency and hardness. The mixing ratio of the above (の), (Β) and (C) is preferably 1: 0.7 to 1.2: 0.5 to 3 in equivalent ratio.

The above (1), (2) and (3) may be used as a mixture, and the mixing ratio is arbitrary.

The above-mentioned photocurable composition is an ultraviolet absorber having the specified absorption coefficient and a photopolymerization initiator having the specified absorption coefficient with respect to a polymerizable monomer and a monomer or an oligomer. And uniformly mixed.

The photocurable composition thus obtained, when irradiated with ultraviolet light, hardly transmits ultraviolet light of 3.50 or less, and produces a colorless and transparent cured product with the naked eye. In the present invention, "hard" The “compound” means a thick cured film or cast product formed on the surface of a substrate. That is, the present invention includes a method for producing a cured film having a thickness of 2 mm or more on the surface of a base material and a method for producing a cast product having a thickness of 2 mm or more. The method of the present invention is particularly useful as a method for producing a cast product having a thickness of 2 mm or more.

The method of the present invention can of course be applied to a method of forming a thin-walled cured film on the surface of a substrate or to the production of a thin-walled cast product.

In order to manufacture a casting using the photocurable composition, the photocurable composition is poured into a transparent mold having an arbitrary shape to a thickness of 2 mm or more, and is cured by irradiating ultraviolet rays. A method of removing the product by removing the mold is adopted. Further, in order to form a cured film on the surface of the substrate using the photocurable composition, the photocurable composition is coated on the substrate using a roller, spray, or the like, and then For the method, a method is used in which a substrate is immersed in a photocurable composition, squeezed with a mouth to a predetermined amount, and then cured by irradiating ultraviolet rays. This makes it possible to provide a transparent thick cured film on the surface of the base material.

In the above method, as a light source for curing the photocurable composition, an ultraviolet lamp having an emission band at 360 to 380 tim is used. UV lamps include, for example, metal-halide lamps. The irradiation time varies depending on the type of lamp and the distance from the lamp to the photocurable composition, but is generally between 1 second and 10 minutes.

Light source with almost no emission band from 360 to 380 nm was used In this case, hardening of the photocurable composition hardly occurs. For example, when an incandescent lamp having an emission band at 400 to 660 nm is used as a light source, the photocurable composition hardly cures even if the incandescent lamp is irradiated for a long time such as 30 minutes.

When curing the photocurable composition, the light source may be irradiated from one side or both sides of the photocurable composition, but preferably from both sides.

When the photocurable composition is cured under the same conditions as above, it can be uniformly cured to the inside, the cured product is visually colorless and transparent, and has a thickness of 2 mm measured at a wavelength of 550 nm. Although the light transmittance of the flat plate depends on the refractive index of the photocurable composition, it is generally about 88 to 93%. On the other hand, when an ultraviolet absorber or a photopolymerization initiator out of the range of the present invention is used, the following problems occur: the curing speed is remarkably slow, the interior is not sufficiently cured, or the coloring is performed.

The photocurable composition of the present invention may be added with additives such as a leveling agent and a pressing agent as long as the object of the present invention is not violated.

Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1

A mixture consisting of 90 g of methyl methacrylate and 10 g of poly (ethylene glycol) acrylate (molecular weight: 350) was used as a UV absorber as a UV absorber. 2—Hydroxy-14-Methoxybenzophenone (The extinction coefficient at 324 nm was 10,000 / M · cm, and the extinction coefficient at 360 nm was 500 / M · cm.) 0.1 g was dissolved. Next, benzoethyl ether (absorption coefficient at 360 nm) was used as the photopolymerization initiator. Was dissolved in 100 / M.cm, 390 nm, 0. 05 g to prepare a photocurable composition. After thoroughly defoaming the composition, it is poured into a mold having a thickness of 3 mm, a width of 500 mm, and a length of 500, and from the top (one side) using a metal-halide dram having a shining band at 360-380 nra. Irradiated with ultraviolet light. The output of the metal halide lamp was 80 W / cm, and the above mold was placed at a distance of 15 cm from the light source. It was completely cured by irradiation for 30 seconds. The obtained cured flat plate with dimensions of about 3 X 500 X 500 mm was irradiated with ultraviolet light of 350ηιη in the direction of 3 mm in thickness direction, and the transmittance of ultraviolet light was measured. It was found that the ultraviolet light was blocked.

Further, when the light transmittance at 550 nm of this cured flat plate was determined, the light transmittance was 92.3%, and it was found that visible light was sufficiently transmitted when surface reflection was considered. The cured plate was colorless and transparent to the naked eye.

Furthermore, the hardened flat plate was sliced from the surface to a certain thickness, and the Barcoal hardness (BH) of the sliced surface was measured. The surface layer was BH38, and the 1 mm sliced surface was BH37, 2 mm. The sliced surface was BH37.

From the above results, the cured flat plate obtained by the present invention has hardly uniform surface and inside hardness, hardened uniformly to the inside, was visually colorless and transparent, and blocked ultraviolet light. 1

In Example 1, instead of 2-hydroxy-4-methoxybenzophenone, phenylzarylate (absorbance at 350 nm) was used. A photocurable composition was prepared in exactly the same manner as in Example 1 except that 0.1 g of an extinction coefficient at 360 nm of a coefficient of 20 / M · cm. 360 nm was used.

This composition was cured under exactly the same conditions as in Example 1 to prepare a cured plate. When the ultraviolet transmittance at 350 nm in the thickness direction of the obtained cured flat plate was measured, the ultraviolet transmittance was 80.7%, and the ultraviolet shielding property was insufficient.

In the above method, when the amount of phenol salicylate was increased and 1.0 g was used, the polymerization was not sufficiently completed due to a significant delay in the polymerization, and the UV transmittance of the cured plate was 350%. At 12.6%, the ability to block ultraviolet light was not yet satisfactory.

Comparative Example 2

In Example 1, 0.05 g of 2,1-getylthioxanthone (extinction coefficient at 3601 ^ is 4.000 / cm, extinction coefficient at 390 nm is 6.800 / Mcm) in place of benzo'ethyl ether A photocurable composition was prepared in exactly the same manner as in Example 1 except for the above. This composition was cured under exactly the same conditions as in Example 1 to prepare a cured plate.

The obtained cured plate was colored yellow and had a light transmittance of 62.6% at 550 nm in the thickness direction, which violated the object of the present invention to obtain a colorless and transparent cured product.

Comparative Example 3

In Example 1, 2-benzoyl-2-methyl-1-one-propenyl-1-one (absorption coefficient at 360 nm was 21 / M · cm, absorbance at 390 nm) was used in place of benzoethyl ether. A photocurable composition was prepared in the same manner as in Example 1 except that 0.05 g of the coefficient was used. This composition was cured under exactly the same conditions as in Example 1 to prepare a cured plate.

The obtained cured flat plate had a Barcol hardness of BH38 on the surface, but the Barcoll hardness of the surface slicing 1 from the surface was BH30 and the Barcoll hardness of the surface slicing 2 mm from the surface was BH14. Yes, the surface had sufficient hardness, but the internal hardness was insufficient.o

In the above method, the curing time is extended to 10 minutes, or the curing amount is increased to 2 g by increasing the amount of 2-hydroxy-12-methynole-1-1-phenylpronon-1-one to 2 g. When a flat plate was prepared, the bar call hardness of the 1 mm and 2 mnr slice surfaces from the surface of the hardened flat plate did not increase, and the hardened flat plate was colored pale yellow.

Example 2

To a monomer mixture consisting of 100 g of diary pentapentyl erythritol, 100 g of pentaerythritol tetrathioglycolate and 200 g of trimethyl phenol triacrylate, 200 g of triacrylate 2 -Hydroxy-4- 4-methoxybenzophenone-5 -Sulfonic acid as an ultraviolet absorber (absorption coefficient at 320 nm is 9.000 / M · cm- 360ηηι is 800 / M · cm) 0. Dissolve 1 and then dissolve 0.05 g of benzyldimethyl ketone (absorption coefficient at 360 nm is U0 / Mcm, extinction coefficient at 390ηπι is 2 / Mcm) Was prepared. This composition was molded into a 6 mm thick, 100 mm wide, 100 vertical glass After pouring into a mold and defoaming sufficiently, ultraviolet rays were irradiated from above and below (both sides) by a metal halide lamp having an emission band at 360 to 380nra. The output of the metal halide lamp was 120 W / cm, and the above mold was placed at a distance of 15 cm from the light source. It was completely cured by irradiation for 30 seconds. When the transmittance of 350 nm ultraviolet light was measured in the direction of 6 mm thickness of the obtained hardened flat plate with dimensions of about 6 x 100 x 100 mm, the transmittance was 0.1%, and almost no ultraviolet light was blocked. Was admitted. When the light transmittance of this cured plate at 550 tim was measured, the light transmittance was 92.0%, and it was found that visible light was sufficiently transmitted when surface reflection was considered. The cured plate was visually colorless and transparent.

Next, the hardened flat plate was sliced from the surface to a certain thickness, and the bar call hardness of the slice surface was measured.The surface layer was BH45, the 1 mm slice surface was BH44, and the 2 mm slice. The stainless steel surface was BH44 and the 3 mm slice surface (center) was BH42.

From the above results, the cured flat plate obtained according to the present invention has almost the same hardness on the surface and inside, hardened uniformly to the inside, was colorless and transparent to the naked eye, and blocked ultraviolet light. . Comparative Example 4

In Example 2, 2—hydroxy-4-methoxybenzophenone—5—instead of sulfonate (2—hydroxy—5—tert-hydroxy) Liazole (extinction coefficient at 345 ηηι is 16.000 / Mcm, extinction coefficient at 360 nm is 10.000 / Mcm) Similarly, a photocurable composition was prepared. This composition was cured under exactly the same conditions as in Example 2 to prepare a cured plate.

The hardened flat plate obtained had a bar-coal hardness of BH45 on the surface, and the surface hardness was 2H, and the Norcoal hardness of the sliced surface of 2 mm and 3 mm was BH 35 and B, respectively. H20. BH13. The surface had sufficient hardness, but the internal hardness was insufficient.

In the above method, the curing time can be extended to 10 minutes or the amount of (2-hydroxyl-5-tert-butyl) -benzotriazole can be reduced to 0.01 g. When a hardened flat plate was prepared by reducing it, the bar call hardness of the slice surface inside the hardened flat plate did not increase.

Comparative Example 5

In Example 2, 1-hydroxycyclohexyzolevidine (the extinction coefficient at 360 nm is cm and the extinction coefficient at 390 nm is 1 / Mcm) instead of benzyldimethylmethylketal

A photocurable composition was prepared in exactly the same manner as in Example 2 except that 0.05 g was used. This composition was cured under exactly the same conditions as in Example 2 to produce and form a cured plate.

The obtained hardened flat plate had a surface Barcol hardness of BH44, but the surface force and the Norco-Hardness of the surface sliced with lmm, 2mm and 3mm were BH35, BH22 and BH, respectively. The surface had sufficient hardness, but the internal hardness was insufficient.

In the above method, the curing time was extended to 10 minutes, or the amount of 1-hydroxycyclohexylphenylketone was increased to 2 g to prepare a cured plate. Hardening The bar call hardness of the slicing surface inside the flat plate did not increase, and the hardened flat plate was colored, and the hardened flat plate intended for the present invention could not be obtained.

Example 3

A photocurable composition having exactly the same composition as in Example 2 was prepared and injected into a glass mold for manufacturing spectacle lenses. After sufficient defoaming, ultraviolet rays were irradiated from above and below (both sides) from both sides of the glass mold by means of a metal halide lamp having a luminous dynamism continuous from 360 to 380 nm. The output of the metal halide lamp was 80 W / cm, and the glass mold was placed at a distance of 18 cm from the light source and completely cured in 30 seconds of irradiation.

The obtained lens is colorless and transparent to the naked eye, the Barcol hardness of the surface and the center is BH45sBH41, respectively, and there is almost no change, and ultraviolet light of a wavelength of 350 nm or less is completely. Was shut off.

Example 4

Bisphenol A diglycidyl ester diacrylate ester (molecular weight 520) As 100 g of ultraviolet light, 100 mg of 2-hydroxy-4- 4-methoxybenzophenone (absorbance at 324 nm) 0.1 / g of 10,000 / M · cm. The extinction coefficient at 360 nm is 500 / M · cm.) 0.1 g is dissolved, and then benzyl dimethyl ketal (140 / M 0.05 g of an absorption coefficient at 2 cm / cm and 390 nm) was dissolved to prepare a photocurable composition. This composition is poured into a glass mold having a thickness of 6 n, a width of 100 、 and a height of 100 、, and after sufficient defoaming, Ultraviolet rays were irradiated from above and below (both sides) using a metal halide lamp having an emission band at 360 to 380 nm. The output of the lamp was 30 W / cm, and the mold was placed at a distance of 15 on from the light source, and was completely cured by irradiation for 30 seconds.

When the transmittance of 350 _nm ultraviolet light was measured in the direction of the thickness 6 の of the obtained cured plate having a size of about 6 X 100 X 100 «, the transmittance was 0.1%, and almost the ultraviolet light was blocked. It was recognized that The light transmittance at 550 nm of the cured flat plate was measured, and the light transmittance was 88.5%. It was found that the visible light was sufficiently transmitted in consideration of the surface reflection. The cured plate was visually colorless and transparent.

Next, the hardened flat plate was sliced from the surface to a certain thickness, and the Barcoll hardness of the sliced surface was measured. The surface layer was BH8. The ™™ slice layer was BH48, and the 2 «slice layer was BH47. The 3 slicing layer (center) was BH46.

From the above results, the cured flat plate obtained by the present invention had almost the same hardness on the surface and the inside, hardened uniformly to the inside, was visually colorless and transparent, and blocked ultraviolet rays.

Comparative Example 6

In Example 4, instead of 2-hydroxy-4-methoxybenzophenone, (2-hydroxy 5-tertiary octyl phenyl) monobenzotriazole (the absorption coefficient at 345 nm was 16,000 / Μ). A photocurable composition was prepared in exactly the same manner as in Example 4 except that 0.1 g of the extinction coefficient at 360 nm was used. This composition was prepared under the same conditions as in Example 4. It was cured to form a cured plate.

The obtained cured flat plate had a bar call hardness of BH48 on the surface, but the bar call hardness of the surface sliced 1 M, 2 «, and 3« from the surface was BH40, BH30, and BH15, respectively. The surface had sufficient hardness, but the internal hardness was insufficient.

In the above method, extend the curing time to 10 minutes or reduce the amount of (2-hydroxy-15-tert-octylphenyl) -benzotriazole to 0.01 g. When a hardened flat plate was prepared, the Barcol hardness of the slicing surface inside the hardened flat plate did not change.

Comparative Example 7

In Example 4, 2-benzyl-2-methyl-2-ethylene-1-propanol was used instead of benzyldimethylmethyl ketal, and the extinction coefficient at 390 nm was about 0 / J1'cm at 390 nm. ) A photocurable composition was prepared in the same manner as in Example 4 except that 0.05 g was used. This composition was cured under exactly the same conditions as in Example 4 to prepare a cured plate.

The obtained cured flat plate had a Barcol hardness of BH 48 on the surface, but had a Barcol hardness of BH38 on the surface sliced 11 »from the surface, and a Barcol hardness of 2 ™ on the surface. BH 23. The bar call hardness of the surface sliced 3 n from the surface was BH 17, and although the surface had sufficient hardness, the internal hardness was insufficient.

In the above method, the curing time can be extended to 10 minutes, or 2-hydroxy 2-methyl 1-phenylamine When the hardened plate was made by increasing the amount of 1-on to 2 g, the Barcol hardness of the 1 «面, 2«, and 3β sliced surfaces from the surface of the hardened plate did not increase. The cured plate was colored pale yellow.

Comparative Example 8

A photocurable composition having the same formulation as in Example 2 was placed in the same glass mold as in Example 2. This mold was placed at a distance of 15 cm from a 500 W incandescent lamp having a main emission band at 400 to 660 nm, and light was irradiated from above and below (both sides). Irradiation was performed for 30 minutes, but no curing was observed. Industrial applications

The photocurable composition of the present invention can be easily and uniformly cured to a deep portion by irradiating ultraviolet rays from an ultraviolet lamp having an emission band at 360 to 380 _nm , and the resulting cured product Are colorless and transparent and do not transmit ultraviolet light, so cast products are windows, skylights such as skylights, vehicle glass substitutes, optical lenses such as eyeglass lenses, camera lenses and condenser lenses, and disc plates. And it can be effectively used for optical materials such as sealing materials.

Claims

The scope of the claims

1. For polymerizable monomers and oligomers,

(1) UV absorption with an extinction coefficient of not less than 2,000 / M ♦ cm at 300-350 nm and an extinction coefficient of not more than 1,000 / Mcm at 360 nm!

(2) A photocurable composition comprising a photopolymerization initiator having an extinction coefficient at 360 to 380 nm of 5Ο / Μ.αη or more and an extinction coefficient at 390 nm of 10 / M.cm or less.

2. The photocurable composition according to claim 1, wherein the polymerizable monomer and the oligomer or oligomer have an extinction coefficient at 390 nm of 10 / cm 2 or less.

3. Polymerizable monomers and oligomers

(i) At least one kind of vinyl selected from among a butyl ester, an acrylate ester, a methacrylate ester, an aromatic vinyl hydrocarbon, a chlorinated vinyl compound and a fluorinated vinyl compound. Nitrile monomer;

(II) Bull ester, acrylate ester, methacrylate ester, aromatic vinyl hydrocarbon, chlorinated vinyl compound, fluorinated vinyl compound, polyvalent aryl compound and at least one molecule A combination of at least one monomer selected from compounds having a cycloacetal group of 2 偭 with mercaptan '; and

(iii) Epoxy, acrylic or meta-relate, polyester-acrylate or meta-relate, polyether or meta-relate, c Recall rate 2. The photocurable composition according to claim 1, wherein the composition is selected from the group consisting of methacrylate, silicone acrylate, and methacrylate. object,

4. Polymerizable monomers include butyl ester, acrylate, methacrylate, aromatic butyl hydrocarbon, vinyl chloride compound, fluorine-containing vinyl compound, and polyvalent compound. And a combination of at least one compound selected from compounds having at least a divalent acetal group in one molecule with a ratio of 37 to 7: 3 (equivalent ratio). Item 2. The photocurable composition according to item 1.

5. Polymerizable monomers and / or oligomers

(A) a compound having at least two cycloacetal groups in one molecule, (B) a mixture comprising a polyvalent thiol and (C) an acrylate ester or a methacrylate ester. 2. The photocurable composition according to item 1, wherein

6. The photocurable composition according to claim 5, wherein the mixing ratio of each monomer is (A) :( B) :( C) = 1: 0.7 to 1.2: 0.5 to 3. Composition.

7. The UV absorber is 2,4-dihydroxybenzophenone 2—hydroxy-4—octadecyloxybenzophenone, 2 hydroxy-4-methoxybenzophenone-1 5—sulfonate, 2 — Claim 1 which is at least one selected from the group consisting of hydroxy 4-methoxybenzophenone and 2'-ethylhexyl-2-cyano-3-phenylphenylamine. A photocurable composition.

8. The photocurable composition according to claim 1, wherein the amount of the ultraviolet absorber is 0.01 to 1% by weight based on the total weight of the polymerizable monomer and / or oligomer.

9. The photocurable composition according to claim 1, wherein the amount of the ultraviolet absorber is 0.02 to 0.5% by weight based on the total weight of the polymerizable monomer and the monomer or oligomer.

10. Photopolymerization initiators include benzyldimethyl ketal, benzophenone, 4,4'-bisdimethylaminoaminobenzophenone, 2-carboxymethylbenzophenone, benzoin, benzoinethylatenore, benzoinisopropyl 2. The light-hardening composition according to claim 1, wherein the composition is at least one selected from ether and benzoin-isobutyl ether.

11. The photocurable composition according to claim 1, wherein the amount of the photopolymerization initiator is 0.01 to 2% by weight based on the total weight of the polymerizable monomer and / or oligomer.

12. The photocurable composition according to claim 1, wherein the amount of the photopolymerization initiator is 0.03 to 0.5% by weight based on the total weight of the polymerizable monomer and / or oligomer.

13. For polymerizable monomers and oligomers or oligomers, (1) the absorption coefficient at 300 to 350 nm is 2,000 / Mcm or more and the extinction coefficient at 360 nm is 1,000 / 11 cm or less. An ultraviolet absorber and (2) a photopolymerization initiator having an extinction coefficient at 360-380 nm of 50 / Μ · αη or more and an extinction coefficient at 390 nm of 10 / M.cm or less The photocurable composition is cured by irradiating it with ultraviolet light using a light source having an emission band of 360 to 380 nm. And a method for producing a cured product.

14. The method according to claim 13, wherein the polymerizable monomer and Z or oligomer have an extinction coefficient at 390 nm of 10 / M · cm or less.

15. Polymerizable monomers and phenolic or oligomeric

(i) at least one vinyl selected from the group consisting of vinyl esters, acrylates, methacrylates, aromatic vinyl hydrocarbons, vinyl chloride compounds and fluorine-containing vinyl compounds; System monomer;

(II) Bull ester, acrylic ester, methacrylic ester, aromatic vinyl hydrocarbon, vinyl vinyl compound, vinyl vinyl compound, polyvalent aryl compound and in one molecule A combination of at least one monomer selected from compounds having at least two cycloacetal groups and mercaptan; and

(iii) Epoxy or metal acrylate, polyester or metal acrylate, polyether or metal acrylate, c Selected from the group consisting of methacrylate, methacrylate, and silicone acrylate or methacrylate, with a molecular weight of 200 to 3,000 The production method according to claim 13.

16. The polymerizable monomer is bürether, acrylate, methacrylate, aromatic bule hydrocarbon, chlorovinyl compound, fluorinated vinyl compound, polyvalent allylic compound and one molecule. Having at least a divalent acetal group in it 13. The production method according to claim 13, which is a combination of at least one compound selected from compounds and a ratio of 3: ヒ to ：: 3 (equivalent ratio) with hymercaptan.

17. Polymerizable monomers and / or oligomers are (A) compounds having at least two cycloacetal groups in one molecule, (B) polyvalent thiols and (C) acrylics. 14. The production method according to claim 13, wherein the mixture is a mixture composed of ester of methyl acrylate or ester of methacrylic acid.

18. The method according to claim 1, wherein the mixing ratio of each monomer is (A) :( B) :( C) = 1: 0.7 to 1.2: 0.5 to 3. .

19. The UV absorber is 2,4—dihydroxybenzophenone 2-hydroxy-1-4—octadesiloxybenzophenone, * 2-hydroxy4—methoxybenzophenone-1-5—sulfo Acids 2—Hydroxy 1—4—Methoxy benzophenone and 2′—Ethylhexyl 2—Cyano 1—3—Feninolecin 13. The production method according to paragraph 13.

20. The process according to claim 13, wherein the amount of the ultraviolet absorber is 0.01 to 1% by weight based on the total weight of the polymerizable monomer and / or oligomer.

21. The photopolymerization initiators are benzyldimethyl ketal, benzophenone, 4,4'-bisdimethylaminobenzophenone, 2—potassium benzophenone, benzoin, benzoinethyl ether, benzoin ether. Soprovir ether and 14. The production method according to claim 13, wherein the production method is at least one member selected from the group consisting of benzene and sobutyl ether.

22. The process according to claim 13, wherein the amount of the photopolymerization initiator is 0.01 to 2% by weight based on the total weight of the polymerizable monomer and Z or oligomer.

23. The production method according to claim 13, which produces a cured product having a thickness of 2 mm or more.