| PATENT NUMBER | This data is not available for free |
| PATENT GRANT DATE | March 14, 2000 |
| PATENT TITLE |
Compound, a process for the preparation thereof, and a resin composition |
| PATENT ABSTRACT | Novel polyester compounds having a benzotriazole group of the invention are obtained by a ring-opening addition-polymerisation of lactones with the alcoholic hydroxyl group of 3-(5-chloro-2H-benzotriazol-2-yl)-5-(1,1-dimethyl-ethyl)-4-hydroxy-benzene -propanol, 3-(2H-benzotriazol-2-yl)-4-hydroxy-benzene-ethanol, 3-(5-methyl-2H-benzotriazol-2-yl)-5-(1-methyl-ethyl)-4-hydroxy-benzene-pro panolbis[3-(2H-benzotriazol-2-yl)-4-hydroxy-benzene-ethanol]methane or the like. These compounds are used as ultraviolet-rays absorbents for thermoplastic resins. The resulting resin composition has an excellent light resistance and chemical resistance |
| PATENT INVENTORS | This data is not available for free |
| PATENT ASSIGNEE | This data is not available for free |
| PATENT FILE DATE | October 1, 1998 |
| PATENT CLAIMS |
We claim: 1. A polyester or ester compound having a benzotriazole group, of formula (1) or (1') ##STR3## wherein R.sup.1 is hydrogen atom, halogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.2 is hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.3 is an alkyl group having 1 to 10 carbon atoms; R.sup.4 to R.sup.5 are a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; n is an integer of 4-8; m is a number of 1-20. 2. A method of synthesizing a compound according to claim 1, characterized in that a compound of formula (2) or (2') is allowed to react with a lactone compound of formula (3) resulting in a ring opening of the lactone (3) compound ##STR4## wherein: R.sup.1 is hydrogen atom, halogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.2 is hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.3 is an alkyl group having 1 to 10 carbon atoms; R.sup.4 to R.sup.5 are a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; n is an integer of 4-8; m is a number of 1-20. 3. An ultraviolet-rays absorbent characterised in that it comprises a polyester or ester compound according to claim 1 or obtained by the method of claim 2. 4. A resin composition characterised in that it contains a synthetic resin and an ultraviolet-rays absorbent according to claim 3. 5. The resin composition according to claim 4, characterised in that said synthetic resin contains at least one kind of resin selected from the group consisting of a polyvinyl-chloride, a polyvinylidene-chloride, a polyolefin, a polycarbonate, a polystyrene, an acrylic resin, a methacrylic resin, a polyamide, a polyester, an acrylonitrile-butadiene-styrene resin and a thermoplastic urethane resin. |
| PATENT DESCRIPTION |
The present invention relates to new polyester compounds having a benzotriazole group and a preparation method thereof. The present invention concerns also an ultraviolet-rays absorbent comprising one of the above-mentioned polyester compounds and a resin composition containing an ultraviolet absorbent which is very light resistant and chemical resistant. Synthetic resins having a great strength, a great durability and that can be used in industrial mold processes are commonly used in various industrial fields, such as, for example, the car industry, electrical and electronical industries, or the construction industry. However, these synthetic resins have several drawbacks. When these synthetic resins are exposed to a light containing ultraviolet rays, such as sunlight, they are deteriorated by the ultraviolet rays and their colour changes. Consequently, the resulting reduction of their molecular weight leads to a drop in their strength. In order to improve the resistance of these synthetic resins to ultraviolet rays, an ultraviolet-rays absorbent is usually added. For example, 2-(2'-hydroxy-5'-methyl-phenyl)benzotriazole, 5-chloro-2-(2'-hydroxy-3', 5'-di-tert-butyl-phenyl)benzotriazole or other benzotriazole like compounds and 2,4-dihydroxy-benzophenone, 2-hydroxy-4octyl-oxy benzophenone or other benzophenone-like compounds known as ultraviolet-rays absorbents. However, these ultraviolet-rays absorbents used in the prior art have a low molecular weight and therefore a low- boiling point. Consequently, the addition of such compounds into synthetic resins involves various drawbacks. For example, when the ultraviolet-rays absorbent is added in a large amount, there is a phase separation between the synthetic resin and the ultraviolet-rays absorbent, thereby reducing the transparency of the synthetic resin and the mechanical strength thereof. Therefore, the amount of ultraviolet-rays absorbent to be added must be limited, if possible, to a small amount. However, in such a case, the light-resistance of the synthetic resin cannot be improved in a satisfactory way. Moreover, during the mold process of the synthetic resin, the ultraviolet-rays absorbent is evaporated off or thermally deteriorated. The ultraviolet-rays absorbent leaks out of the surface of the molded articles. It is therefore impossible to confer a light-resistance to these synthetic resins which is stable for a long period of time. In order to solve the above-mentioned drawbacks, there has been tried an attempt (JP-A-60-38411, JP-A-62181360 and JP-A-3-281685) that a group having a polymerizable double bond such as a vinyl group, is added to the above-mentioned ultraviolet-rays absorbents, and then it is polymerised to increase the molecular weight, whereby, compatibility with resins is improved and there are prevented evaporation, thermal decomposition and bleeding of the ultraviolet-rays absorbent. However, the above-mentioned polymerizable ultraviolet-rays absorbents have the following drawbacks, therefore leaving the door open for further improvements. According to the type of the synthetic resin used, the compatibility of the resin and the ultraviolet-rays absorbent may not be sufficient, thereby decreasing the mechanical strength of the resin. This tendency is particularly remarkable in the case of a polyolefin, a polyvinyl-chloride, a polyvinylidene-chloride or other thermoplastic resins. Moreover, a long-term light resistance cannot be obtained. Further, polyvinyl-chlorides, polyvinylidene-chlorides, polycarbonates, polyarnides, polyesters and other thermoplastic resins such as thermoplastic polyurethane resins have an extremely high mechanical strength and are widely used as a variety of materials in mold processes. However, polyvinyl-chlorides, polyvinylidene-chlorides, polycarbonates, polyesters, and thermoplastic urethane resins are degraded by alkaline compounds which reduce their mechanical strength. Resins such as polyamides are soluble in widely-used solvents such as methanol. Improvements regarding the resins' resistance to chemicals such as alkaline compounds and their solvent resistance have been therefore also required. The inventors of the present invention have succeeded in obtaining ultraviolet-rays absorbents which are polymerizable compounds, by using, as starting materials, known ultraviolet-rays absorbents. The compatibility of these polymerizable compounds and the resin is excellent for a wide range of resins. The ultraviolet-rays absorbents of the invention confer an excellent light resistance to the resins without any loss of the desirable features of the resins. The ultraviolet-rays absorbents of the invention are not evaporated off or thermally deteriorated during the mold process and they do not leak out the molded articles. Thus, the inventors discovered how to obtain a synthetic resin having a light resistance stable for a long period of time. Moreover, the inventors discovered that an ultraviolet-rays absorbent containing the above-mentioned specified polymerizable compounds is able to confer an excellent resistance to alkaline compounds and an excellent solvent resistance, to a synthetic resin having a poor resistance to alkaline compounds and a poor solvent resistance. The present invention has been completed by the findings. Formulae (1) and (1') show the polyester compounds provided by a first aspect of the present invention. These polyester compounds have a benzotriazole group. ##STR1## wherein: R.sup.1 is hydrogen atom, halogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.2 is hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.3 is an alkyl group having 1 to 10 carbon atoms; R.sup.4 to R.sup.5 are hydrogen atoms or an alkyl group having 1 to 10 carbon atoms; n is an integer of 4-8; m is a number of 1-20. A second aspect of the present invention also provides a method for preparing the above-mentioned polyester compounds containing a benzotriazole group described in the first aspect of the invention. According to the second aspect of the present invention, these polyester compounds may be obtained by polymerising the compounds of formulae (2) and (2') with a lactone compound of formula (3). This polymerisation reaction is a ring-opening addition-polymerisation of the lactone compound. ##STR2## wherein: R.sup.1 is hydrogen atom, halogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.2 is hydrogen atom or an alkyl group having 1 to 10 carbon atoms; R.sup.3 is an alkyl group having 1 to 10 carbon atoms; R.sup.4 to R.sup.5 are a hydrogen atom or an alkyl group having 1 to 10 carbon atoms; n is an integer of 4-8; m is a number of 1-20. A third aspect of the present invention also provides ultraviolet-rays absorbents comprising the above-mentioned polyester compounds containing a benzotriazole group described in the first aspect of the present invention. Further, a fourth aspect of the present invention provides synthetic-resin compositions containing a synthetic resin and the above-mentioned ultraviolet-rays absorbents described in the third aspect of the invention. The resin compositions of a fifth aspect of the invention comprise, as a synthetic resin, at least one synthetic resin selected from the group consisting of a polyvinyl-chloride, a polyvinylidene-chloride, a polyolefin, a polycarbonate, a polystyrene, an acrylic resin, a methacrylic resin, a polyamide, a polyester, an acrylonitrile-butadiene-styrene resin or a thermoplastic urethane resin. The resin compositions according to the invention have a high and time-stable light resistance and chemical resistance. FIG. 1 is a graph showing the elongation ratio at rupture, after a light-exposure test, of the products of the prior art (Comparative Example 1) and the products of the present invention (Example 1), respectively; FIG. 2 is a graph showing the colour difference (.DELTA.Eab*), after a light-exposure test, of the products of the prior art (Comparative Example 4) and the products of the present invention (Example 4), respectively; FIG. 3 is a graph showing the colour difference (.DELTA.Eab*), after a light-exposure test, of the products of the prior art (Comparative Example 5 5) and the products of the present invention (Example 5), respectively; FIG. 4 is a graph showing the colour difference (.DELTA.Eab*), after a light-exposure test, of the products of the prior art (Comparative Example 6) and the products of the present invention (Example 6), respectively; FIG. 5 shows the infrared-absorption spectrum of the compound (3) 10 obtained in Synthesis Example 3; FIG. 6 is the .sup.1 H-NMR spectrum of the compound (3) obtained in Synthesis Example 3; FIG. 7 is the ultraviolet and visible light-absorption spectrum of the compound (3) obtained in Synthesis Example 3; FIG. 8 is the ultraviolet and visible light-absorption spectrum of the compound (4) obtained in Synthesis Example 4; FIG. 9 is a graph showing the elongation ratio at rupture, after a light-exposure test, of the products of the prior art (Comparative Example 10) and the products of the present invention (Example 10), respectively; FIG. 10 is a graph showing the colour difference (.DELTA.Eab*), after a light-exposure test, of the products of the prior art (Comparative Example 13) and the products of the present invention (Example 13), respectively; FIG. 11 is a graph showing the colour difference (.DELTA.Eab*), after a light-exposure test, of the products of the prior art (Comparative Example 14) and the products of the present invention (Example 14), respectively; FIG. 12 is a graph showing the colour difference (.DELTA.Eab*) after a 30 light-exposure test, of the products of the prior art (Comparative Example 15) and the products of the present invention (Example 15), respectively; The polyester compounds containing a benzotriazole group of the above-mentioned formulae (1) and (1') of the present invention are novel compounds and may be used as ultraviolet-rays absorbents for synthetic resins. The method of preparing the above-mentioned compounds having a benzotriazole group represented by the above-mentioned formula (1) or (1') is a ring-opening addition-polymerisation of the lactone compound (3) of formula (3) with one of the alcohols of formulae (2) and (2'). In the above-mentioned formulae (1) and (1'), m is an integer which indicates the number of molecules of each polymer. However, regarding the whole polymer, m is not necessarily an integer. When the values of m or m' are less than 1 in the whole polymer, the ultraviolet-rays absorbent tends to leak-out of the surface of the molded articles. On the contrary, when the values of m or m' are greater than 20, the ultraviolet-rays absorbability is unpreferably insufficient. However, regarding the ultraviolet-rays absorbents of formulae (1) and (1'), m and m' are not limited to the above-mentioned values. The alcohols of formula (2) may be, specifically, 3-(5-chloro-2H-benzotriazol-2-yl)-5-(1,1-dimethyl-ethyl)-4-hydroxy-benzene -propanol3-(2H-benzotriazol-2-yl)-4-hydroxy-benzene-ethanol, 3-(5-methyl-2H-benzotriazol-2-yl)-5-(1-methyl-ethyl)-4-hydroxy-benzene-pro panol or the like. The alcohols of formula (2') may be, for example, bis-[3-(2H-benzotriazol-2-yl)-4-hydroxy-benzene-ethanol]methane or the like. In formula (2') the two benzotriazole rings may be substituted by the group R.sup.1 of formula (2). These two benzotriazole rings may be substituted by similar R.sup.1 groups or by different R.sup.1 groups. In the formulae (2) and (2'), ethanol, propanol or other alcohols which substitute the benzene ring may be linear alcohols or branched alcohols. The above-mentioned alcohols may be synthetic products or tradely available products. Otherwise, they can be obtained by reducing tradely-available benzotriazole-type ultraviolet-rays absorbents by using lithium-aluminium hydride, etc. .epsilon.-caprolactone, trimethyl-.epsilon.-caprolactone, monomethyl-.epsilon.-caprolactone, .gamma.-butyrolactone, .delta.-valerolactone, or the like, may be used as the lactone compound of the above-mentioned formula (3). The catalysts that may be used for the ring-opening addition-polymerisation are, for example, tetraethyl-titanate, tetrabutyl-titanate, tetrapropyl-titanate, or other organic titanate-compounds, stannous octoate, dibutyl-tin-oxide, dibutyl-tin-dilaurate, a n-butyl-tin tris(alkanoate) or other organic tin-compounds, stannous chloride, stannous bromide, stannous iodide or other stannous halide compounds. The amount by weight of catalyst added is 0.1-10,000 ppm and preferably 1-5,000 ppm based on the amount by weight of alcohol used. When the amount of catalyst is less than 0.1 ppm, the ring-opening reaction of the lactones is remarkably slown down which is not economically interesting. On the contrary, when the amount of catalyst is more than 10,000 ppm, the ring-opening reaction occurs quickly but when the obtained polyester compounds containing a benzotriazole group are used to form synthetic resins, these resins have a poor durability and a poor water resistance. The reaction temperature is 90.degree. C.-240.degree. C. and preferably 100.degree. C.-220.degree. C. When the reaction temperature is less than 90.degree. C., the ring-opening reaction of the lactones is remarkably slown down which is not economically interesting. On the contrary, when the reaction temperature is more than 240.degree. C., the polylactones obtained by ring-opening addition-polymerisation are depolymerized which is not desirable. Moreover, when the reaction is performed under an inert gas atmosphere, such as a nitrogen gas atmosphere, particularly good results regarding the colour of the final product can be obtained. The polyester compounds containing a benzotriazole group of the invention may be synthesised according to the aforementioned method. According to the present invention, the synthetic resins that can be synthesised by adding in a resin, as an ultraviolet absorbent, the polyester compounds containing a benzotriazole group of the invention (hereinafter, referred as to ultraviolet-rays absorbable compounds or ultraviolet-rays absorbable polymers), as a ultraviolet-rays absorbable compound, to a resin, are not limited. Any type of known resin may be used. However, the thermoplastic resins are the most suitable because it is very easy to add the polyester compounds containing a benzotriazole group of the invention thereinto. The thermoplastic resins that may be used are, for example, a polyvinyl-chloride, a polyvinylidene-chloride, a polyolefin, a polycarbonate, a polystryrene, an acrylic resin, a methacrylic resin, a polyamide, a polyester, an acrylonitrile-butadiene-styrene resin (ABS), a thermoplastic polyurethane resin, a copolymer of vinyl-chloride and vinylidene-chloride-acrylonitrile resin, an acrylonitrile-styrene resin (AS), a vinyl-acetate resin, a polyphenylene-ether, a polysulphone, a polyether sulphone, a polyether-ether-ketone or other crystalline plastics. Preferably, a polyvinyl-chloride, a poly-vinylidene-chloride, a polyolefin, a polycarbonate, a polystyrene, an acrylic resin, a methacrylic resin, a polyamide, a polyester, an ABS resin and a thermoplastic urethane resin may be, for example, used. Among them, more preferably and, for example, a polyvinyl-chloride, a polyvinylidene-chloride, a polycarbonate, a polyester, a thermoplastic urethane or other thermoplastic resin having a poor alkali resistance and a polyamide or other thermoplastic resin having a poor solvent resistance may be used. According to the present invention, one, two or more kinds of resin may be used. According to the present invention, the relative proportions of the resin and the ultraviolet-rays absorbent of formulae (1) and (1') are not limited. However, usually, the proportions are, in weight ratio: (resin(s) amount (amount by weight): ultraviolet-rays absorbent (amount by weight) 80-99.995:20-0.005 and more preferably, 90-99:10-0.1. The resin compositions of the invention may also optionally contain at least one sort of the following known additives: antioxidants, photostabilisers, process stabilisers, anti-aging agents and compatibilizing agents. The anti-oxidants that can be used are, for example, bis-[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl)1, 6 hexane-diol, 3,5-di-tert-butyl-4-hydroxy-benzyl-phosphonate-diethyl ester or other hindered phenol type anti-oxidants, dilauryl-3,3'-dithio-dipropionate or other organic sulphuric anti-oxidants, trialkyl-phenyl-phosphate or other phosphorous-containing anti-oxidants. As the photostabiliser, for example, bis-(2, 2, 6, 6-tetramethyl-4-piperidyl)sebacate or other hindered-amine photo-stabilisers may be used, as well as dibutyl-dithio-nickel-carbamate or other salts of nickel. As the process stabiliser, for example, tris-(2, 4-di-tert-butyl phenyl)phosphite or other phosphorous-containing process stabilisers may be used. The anti-aging agents may be, for example, 1, 1-bis-(4-hydroxy phenyl)cyclohexene, N,N'-diphenyl-p-phenylene-diamine or the like. The compatibilizing agents may be, for example, a block copolymer of styrene-butadiene-styrene, a block copolymer of styrene-ethylene butylene-styrene or other thermoplastic rubbers. The amount of these additives is not limited but usually, it represents about , 0.01 to 20 weight % based on the synthetic resin. The compositions of the invention can be employed in all uses in which the synthetic resin can be employed. Preferably, the resins of the invention may be used when there are risks in being exposed to a light such as sunlight and ultraviolet rays. Specifically, this means that they can be used as glass-substitute products or as glass coating, for houses, equipment, for windows of means of transport, as a coating for lighting glass and for light-sources protecting glass, as an internal or external painting for means of transport, as a material to produce light sources such as florescent lamps or mercury lamps which emit ultraviolet-rays, for producing precise devices, as a material for electrical or electronic devices, As a material for cutting-off electromagnetic waves or the like which are generated by a variety of displays, for food, for chemicals, pharmaceuticals, as a coating or a container of pharmaceuticals. The compositions of the present invention may be used to produce sheets or films that may be used in the agricultural field. The compositions of the present invention may be used for printing materials, such as colorants, in cosmetics for preventing fading, in creams for stopping sunburn, in shampoos or rinses, or other hair care products, in sponge wears, stockings, for making fibres used to manufacture clothes or other articles such as hats or the like, curtains, carpets, for furniture such as wall paper, for plastic lenses, contact lenses, artificial eyes or other medical devices, optical filters, prisms, mirrors, optical articles for photographic material, tapes, ink or other stationery articles, for marker boards, or as a coating for the surface of marking devices. Although, the present invention will be further explained with reference to the following Synthesis Examples (preparation of an ultraviolet-rays absorbent) Examples (preparation of a synthetic-resin composition) and Comparative Examples, the present invention is not limited by those. It is to be noted that the term % used hereinafter is a % by weight (wt %), unless specified otherwise. (i) Light-exposure test The device used is a dew-cycle sunshine weather-meter WEL-SUN-DC manufactured by Suga Shikenki CO., Ltd. The light source used is a carbon arc with a raining cycle of 18 min per 120 min. The temperature of the black panel was set at 80.degree. C. (ii) Elongation at rupture test The device used is a Shimadzu Autograph DSC of Shimadzu CO., Ltd. The measurement conditions were: 200 kg/FS, cross-head speed=50 mm/min, GL=30 mm. At first, we will describe the ultraviolet-rays absorbent of the formula 1. |
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