JP2016101188A - Molded body for medical use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molded body for medical use, in which generation of a crack of the molded body due to storage and/or usage under a low temperature of -30°C or lower is reduced.SOLUTION: The molded body for medical use, which is to be used and/or stored under the temperature of -30°C or lower, is obtained by molding a copolymerized polyethylene terephthalate comprising a glycol component (component A) and a dicarboxylic acid component (component B) where the glycol component is an ethylene glycol (component A-1), and the dicarboxylic acid component is a dicarboxylic acid comprising 94 to 99 mol% of a terephthalic acid (component B-1) and 1 to 6 mol% of an isophthalic acid (component B-2).SELECTED DRAWING: None

Description

  The present invention is a molded article obtained by molding a copolymerized polyethylene terephthalate obtained by copolymerizing isophthalic acid as a part of a dicarboxylic acid component, and is used and / or stored at a low temperature of less than -30 ° C. The present invention relates to a molded product for medical use in which cracking of the material is suppressed.

In recent years, in medical containers and medical devices used in the medical field, the material switching from glass to resin has been progressing because it is difficult to break when dropped. In particular, medical containers such as vacuum blood collection tubes and prefilled syringes are easily damaged during transportation and handling operations, and therefore, resin containers such as polyethylene, vinyl chloride, and polyethylene terephthalate are preferred. Among them, polyethylene terephthalate which is excellent in gas barrier properties and visibility and does not generate chlorine gas during combustion is particularly preferred and used.
By the way, the blood collected by the vacuum blood collection tube is stored frozen to maintain freshness. Conventionally, the storage temperature at the time of freezing storage is −10 to −20 ° C. However, in recent years, it has been stored at a low temperature below −30 ° C. due to the advancement of the freezing storage technology. Along with this, at a low temperature of less than −30 ° C., the vacuum blood collection tube is broken due to the embrittlement of polyethylene terephthalate and the stress caused by the freezing and expansion of blood, and the blood is scattered.

  Patent Document 1 discloses a technique in which a copolymerized polyethylene terephthalate copolymerized with 5 to 15 mol% of isophthalic acid as an acid component is used in a vacuum blood collection tube, and Patent Document 2 copolymerizes polyethylene terephthalate and isophthalic acid. Techniques have been shown for using a mixture of polyethylene terephthalate in a vacuum blood collection tube. However, in any case, the purpose of copolymerizing isophthalic acid is to improve gas barrier properties, and there is no suggestion of the problem of cracking at low temperature storage below -30 ° C. Therefore, it is desired to develop a vacuum blood collection tube in which the generation of cracks is suppressed even at temperatures lower than −30 ° C.

JP 2003-102709 A Japanese Patent Laid-Open No. 3-222942

  An object of the present invention is to provide a medical molded article in which occurrence of cracks when used and / or stored at a low temperature of less than -30 ° C is suppressed.

  As a result of intensive research aimed at achieving the above-mentioned object, the present inventors have used a molded product obtained by molding a copolymerized polyethylene terephthalate obtained by copolymerizing isophthalic acid in a specific range at less than -30 ° C. It was discovered that cracking when used for storage was suppressed, and the above problem could be solved.

  That is, a copolymerized polyethylene terephthalate comprising a glycol component (A component) and a dicarboxylic acid component (B component), wherein the glycol component is ethylene glycol (A-1 component), and the dicarboxylic acid component is terephthalic acid ( B-1 component) 94-99 mol% and isophthalic acid (B-2 component) 1-6 mol% dicarboxylic acid copolymerized polyethylene terephthalate obtained by molding and used and / or stored below -30 ° C A medical molded body to be used is provided. Examples of the medical molded body include petri dishes, centrifuge tubes, flasks, containers, medical tubes, infusion bags, and the like in addition to the vacuum blood collection tube. The present invention includes a method of using and / or storing the medical molded body at a temperature below -30 ° C.

  The present invention can suppress cracking of a molded article for medical use that is used and / or stored at temperatures below -30 ° C. In addition, since isophthalic acid is copolymerized, it has excellent gas barrier properties and is effective for maintaining the degree of vacuum.

It is a perspective view of the vacuum blood collection tube concerning this invention. It is a longitudinal cross-sectional view of the vacuum blood collection tube concerning this invention.

  Hereinafter, a method for preparing a copolymerized polyethylene terephthalate used in the medical molded article of the present invention and a molding method will be sequentially described.

The copolymerized polyethylene terephthalate used in the present invention comprises ethylene glycol (A-1 component) as a glycol component (A component), 94 to 99 mol% of terephthalic acid (B-1 component) as a dicarboxylic acid component, and isophthalic acid (B- It is a copolymerized polyethylene terephthalate using a dicarboxylic acid consisting of 2 to 6 mol%.
The copolymerization ratio of terephthalic acid (B-1 component) and isophthalic acid (B-2 component) in the dicarboxylic acid is preferably 94 to 98 mol% for the B-1 component, 2 to 6 mol% for the B-2 component, The B-1 component is preferably 95 to 98 mol%, the B-2 component is 2 to 5 mol%, and most preferably the B-1 component is 95 to 97 mol%, and the B-2 component is 3 to 5 mol%. When the ratio of the B-2 component is outside the range of 1 to 6 mol%, cracking is not suppressed when stored and used at less than -30 ° C.

  The intrinsic viscosity (IV) of the copolymerized polyethylene terephthalate is preferably 0.5 to 0.8 dl / g. The range of the intrinsic viscosity is more preferably 0.55 to 0.75 dl / g, still more preferably 0.55 to 0.7 dl / g. If the intrinsic viscosity is greater than 0.8 dl / g, it is necessary to increase the cylinder temperature due to a decrease in fluidity during injection molding, which may result in a longer molding cycle. On the other hand, if the intrinsic viscosity is less than 0.5 dl / g, the toughness is lowered, and cracking at a low temperature of less than −30 ° C. is likely to occur. The intrinsic viscosity is 0.6 g of the resin heated and melted in 50 ml of a phenol / tetrachloroethane = 3/2 (weight ratio) mixed solvent, cooled to room temperature, and the viscosity of the obtained resin solution is the Ostwald viscosity. Measurement is performed at a temperature of 35 ° C. using a tube, and the obtained solution viscosity data is used.

The copolymerized polyethylene terephthalate of the present invention can be produced by either a transesterification method or a direct esterification method. In the case of producing by the transesterification method, a transesterification reaction catalyst is required.
The transesterification reaction catalyst is not particularly limited, and manganese compounds, calcium compounds, magnesium compounds, titanium compounds, zinc compounds, sodium compounds, potassium compounds, cerium compounds, lithium compounds, etc. that are generally widely used as transesterification catalysts for polyethylene terephthalate Is mentioned. Further, a cobalt compound may be contained as a transesterification reaction catalyst that also acts as a color adjusting agent.

  When the copolymerized polyethylene terephthalate of the present invention is produced by a direct esterification method, it is not necessary to deactivate the catalyst because a transesterification reaction catalyst is not used as in the case of the above transesterification method. It is preferable to add such that the remaining amount of the compound is 5 to 100 mmol% with respect to the total acid component. If the residual amount of the phosphorus compound is in the above range, it is preferable in terms of heat resistance and hue.

  As the polycondensation catalyst, a titanium compound, an antimony compound and a germanium compound are preferably used. Examples of the antimony compound include antimony oxide, antimony acetate, and antimonic acid glycolate, among which antimony trioxide is preferably used. When the antimony compound is contained, the content of the antimony compound is preferably 5 to 40 mmol% based on the total acid component in terms of antimony trioxide. When the content of the antimony compound is less than 5 mmol%, the polymerization activity is low, the polycondensation time becomes long, and it is not preferable from an economic viewpoint such as a decrease in production cycle. Since it is inferior also in quality, it is not preferable. When the content of the antimony compound exceeds 40 mmol%, it is not preferable from the viewpoint that the amount of side reaction products due to acceleration of the hue surface and decomposition reaction such as blackening due to precipitation of the antimony compound increases.

As the germanium compound, germanium dioxide is preferably used. When a germanium compound is contained, the content of the germanium compound is preferably 15 to 50 mmol% with respect to the total acid component. If it is less than 15 mmol%, the polymerization activity is low, the polycondensation time becomes long, and it is not preferable in terms of economy such as a decrease in production cycle, etc., but it is also inferior in terms of quality such as increase of side reaction products and deterioration of hue, etc. Absent. When the content of the germanium compound exceeds 50 mmol%, it is not preferable in that the side reaction product increases due to the promotion of the decomposition reaction.
Tetraalkyl titanate is preferably used as the titanium compound. When a titanium compound is contained, n-butyl phosphate is required as a stabilizer. It is necessary that the molar ratio (P / Ti) of phosphorus atoms to titanium atoms contained is 1 to 3. When P / Ti is less than 1, the phosphorus atom concentration is relatively reduced, so that the hue of the resulting polymer becomes inadequate and yellowish, and its heat resistance may be lowered. . On the other hand, if the value of P / Ti exceeds 3, the phosphorus atom concentration is relatively increased, which is not preferable in terms of economics such as a decrease in polymerizability, that is, a polycondensation reaction rate. Moreover, it is preferable that it is 2-40 mmol% as content of a titanium compound with respect to all the acid components. When the content of the titanium compound is less than 2 mmol%, the polymerization activity is low, the polycondensation time becomes long, and this is not preferable in terms of economy such as a reduction in production cycle. When the content of the titanium compound exceeds 40 mmol%, the resulting polymer has an insufficient hue and becomes yellowish, which may reduce its practicality.

In order to adjust the copolymerized polyethylene terephthalate to a desired intrinsic viscosity, solid phase polymerization can be further applied. The reaction temperature in the solid phase polymerization is preferably 230 ° C. or lower. When the solid-state polymerization reaction temperature is carried out exceeding 230 ° C., the degree of crystallinity of the resulting polymer is increased, the appearance of the molded product is impaired, and it acts as a nucleating agent, resulting in whitening of the molded product. .
In addition, the polyethylene terephthalate of this invention can contain each additive, such as antioxidant and a mold release agent, in the range which is not contrary to the meaning of this invention.

<Antioxidant>
In the present invention, as the antioxidant, at least one antioxidant selected from the group consisting of hindered phenol compounds, phosphite compounds, phosphonite compounds, and thioether compounds can be used. By blending an antioxidant, not only is the hue and fluidity at the time of molding stabilized, it is also effective in improving hydrolysis resistance.

  Examples of the hindered phenol compound include α-tocopherol, butylhydroxytoluene, sinapyl alcohol, vitamin E, n-octadecyl-β- (4′-hydroxy-3 ′, 5′-di-tert-butylfel) propionate. 2-tert-butyl-6- (3′-tert-butyl-5′-methyl-2′-hydroxybenzyl) -4-methylphenyl acrylate, 2,6-di-tert-butyl-4- (N, N-dimethylaminomethyl) phenol, 3,5-di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert-butylphenol), 4,4′-methylenebi (2,6-di-tert-butylphenol), 2,2′-methylenebis (4-methyl-6-cyclohexylphenol), 2,2′-dimethylene-bis (6-α-methyl-benzyl-p-cresol) ) 2,2′-ethylidene-bis (4,6-di-tert-butylphenol), 2,2′-butylidene-bis (4-methyl-6-tert-butylphenol), 4,4′-butylidenebis (3- Methyl-6-tert-butylphenol), triethylene glycol-N-bis-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, 1,6-hexanediol bis [3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate], bis [2-tert-butyl-4-methyl 6- ( -Tert-butyl-5-methyl-2-hydroxybenzyl) phenyl] terephthalate, 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1 , 1, -dimethylethyl} -2,4,8,10-tetraoxaspiro [5,5] undecane, 4,4′-thiobis (6-tert-butyl-m-cresol), 4,4′-thiobis (3-methyl-6-tert-butylphenol), 2,2′-thiobis (4-methyl-6-tert-butylphenol), bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide, 4 , 4′-di-thiobis (2,6-di-tert-butylphenol), 4,4′-tri-thiobis (2,6-di-tert-butylphenol) ), 2,2-thiodiethylenebis- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis (n-octylthio) -6- (4-hydroxy -3 ′, 5′-di-tert-butylanilino) -1,3,5-triazine, N, N′-hexamethylenebis- (3,5-di-tert-butyl-4-hydroxyhydrocinnamide), N, N′-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butyl Phenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tris (3,5-di-tert-butyl) 4-hydroxyphenyl) isocyanurate, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6- Dimethylbenzyl) isocyanurate, 1,3,5-tris 2 [3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl isocyanurate, and tetrakis [methylene-3- (3 ′, 5′-di-tert-butyl-4-hydroxyphenyl) propionate] methane and the like. Among the above compounds, tetrakis [methylene-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate] methane, octadecyl-3- (3,5-di-tert-butyl-) is used in the present invention. 4-hydroxyphenyl) propionate and 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4 , 8,10-Tetraoxaspiro [5,5] undecane is preferably used. Particularly preferred is octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate. All of these are readily available. The said hindered phenol type compound can be used individually or in combination of 2 or more types.

  Phosphite compounds include triphenyl phosphite, tris (nonylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl mono Phenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, tris (diethylphenyl) phosphite, tris (di-iso-propylphenyl) phosphite, tris (di-n-butylphenyl) ) Phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tris (2,6-di-tert-butylphenyl) phosphite, distearyl pentae Thritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis ( 2,6-di-tert-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite, phenylbisphenol A penta Examples include erythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, and dicyclohexylpentaerythritol diphosphite. Furthermore, as other phosphite compounds, those that react with dihydric phenols and have a cyclic structure can be used. For example, 2,2′-methylenebis (4,6-di-tert-butylphenyl) (2,4-di-tert-butylphenyl) phosphite, 2,2′-methylenebis (4,6-di-tert- Butylphenyl) (2-tert-butyl-4-methylphenyl) phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, and the like. Suitable phosphite compounds are distearyl pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methyl). Phenyl) pentaerythritol diphosphite, and bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite.

  Also, for example, 2,4,8,10-tetra-t-butyl-6- [3- (3-methyl-4-hydroxy-5-t-butylphenyl) propoxy] dibenzo [d, f] [1,3 , 2] dioxaphosphine [commercially available as “Sumilyzer GP” (manufactured by Sumitomo Chemical Co., Ltd.). 2,10-dimethyl-4,8-di-t-butyl-6- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propoxy] -12H-dibenzo [d, g] [1,3,2] dioxaphosphocin, 2,4,8,10-tetra-t-butyl-6- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propoxy] dibenzo [D, f] [1,3,2] dioxaphosphine, 2,4,8,10-tetra-t-pentyl-6- [3- (3,5-di-t-butyl-4- Hydroxyphenyl) propoxy] -12-methyl-12H-dibenzo [d, g] [1,3,2] dioxaphosphocin, 2,10-dimethyl-4,8-di-t-butyl-6- [3 -(3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -12H Dibenzo [d, g] [1,3,2] dioxaphosphocine, 2,4,8,10-tetra-t-pentyl-6- [3- (3,5-di-t-butyl-4- Hydroxyphenyl) propionyloxy] -12-methyl-12H-dibenzo [d, g] [1,3,2] dioxaphosphocin, 2,4,8,10-tetra-t-butyl-6- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -dibenzo [d, f] [1,3,2] dioxaphosphine, 2,10-dimethyl-4,8-di -T-butyl-6- (3,5-di-t-butyl-4-hydroxybenzoyloxy) -12H-dibenzo [d, g] [1,3,2] dioxaphosphocin, 2,4,8 , 10-Tetra-t-butyl-6- (3,5-di-t-butyl-4- Roxybenzoyloxy) -12-methyl-12H-dibenzo [d, g] [1,3,2] dioxaphosphocin, 2,10-dimethyl-4,8-di-t-butyl-6- [3- (3-Methyl-4-hydroxy-5-t-butylphenyl) propoxy] -12H-dibenzo [d, g] [1,3,2] dioxaphosphocine, 2,4,8,10-tetra-t -Butyl-6- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propoxy] -12H-dibenzo [d, g] [1,3,2] dioxaphosphocine, 2,10 -Diethyl-4,8-di-t-butyl-6- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propoxy] -12H-dibenzo [d, g] [1,3 2] Dioxaphosphocin, 2,4,8,10-tetra-t-butyl Ru-6- [2,2-dimethyl-3- (3-t-butyl-4-hydroxy-5-methylphenyl) propoxy] -dibenzo [d, f] [1,3,2] dioxaphosphine And so on. All of these are readily available. The above phosphite compounds can be used alone or in combination of two or more.

  Examples of the phosphonite compound include tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3′-biphenyl. Range phosphonite, tetrakis (2,4-di-tert-butylphenyl) -3,3'-biphenylene diphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,4'-biphenylene diphospho Knight, tetrakis (2,6-di-tert-butylphenyl) -4,3′-biphenylene diphosphonite, tetrakis (2,6-di-tert-butylphenyl) -3,3′-biphenylene diphosphonite, Bis (2,4-di-tert-butylphenyl) -4-phenyl-phenylphosphonite, bis (2,4- -Tert-butylphenyl) -3-phenyl-phenylphosphonite, bis (2,6-di-n-butylphenyl) -3-phenyl-phenylphosphonite, bis (2,6-di-tert-butylphenyl) Examples include -4-phenyl-phenyl phosphonite, bis (2,6-di-tert-butylphenyl) -3-phenyl-phenyl phosphonite. Tetrakis (di-tert-butylphenyl) -biphenylenediphosphonite, bis (di-tert-butylphenyl) -phenyl-phenylphosphonite are preferred, and tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite Knight and bis (2,4-di-tert-butylphenyl) -phenyl-phenylphosphonite are more preferred. Such a phosphonite compound is preferable because it can be used in combination with a phosphite compound having an aryl group in which two or more alkyl groups are substituted. The phosphonite compound is preferably tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite, and stabilizers based on the phosphonite are Sandostab P-EPQ (trademark, manufactured by Clariant) and Irgafos. P-EPQ (trademark, manufactured by CIBA SPECIALTY CHEMICALS) is commercially available and any of them can be used. The said phosphonite type compound can be used individually or in combination of 2 or more types.

  Specific examples of thioether compounds include dilauryl thiodipropionate, ditridecyl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerythritol-tetrakis (3-lauryl thiopropionate), Pentaerythritol-tetrakis (3-dodecylthiopropionate), pentaerythritol-tetrakis (3-octadecylthiopropionate), pentaerythritol tetrakis (3-myristylthiopropionate), pentaerythritol-tetrakis (3-stearylthio) Propionate) and the like. The said thioether type compound can be used individually or in combination of 2 or more types.

The content of the antioxidant is preferably 0.01 to 2 parts by weight, more preferably 0.03 to 1 part by weight, and still more preferably 0.05 to 0.5 parts by weight with respect to 100 parts by weight of the copolymerized polyethylene terephthalate. Part. When the content of the antioxidant is less than 0.01 parts by weight, the antioxidant effect is insufficient, and not only the hue and fluidity at the time of molding become unstable, but also the hydrolysis resistance may deteriorate. . In addition, when the content is more than 2 parts by weight, the reaction component derived from the antioxidant may be deteriorated and the hydrolysis resistance may be deteriorated.
Further, it is preferable to use a combination of one or more of the hindered phenol compounds and phosphite compounds, phosphonite compounds, and thioether compounds. By using a combination of one or more of hindered phenol compounds and phosphite compounds, phosphonite compounds, and thioether compounds, a synergistic effect as a stabilizer is exhibited, and hue and flow during molding are further improved. It is effective in stabilizing the properties and improving the hydrolysis resistance.

<Release agent>
In the present invention, a release agent can be used. Specific examples of release agents include fatty acids, fatty acid metal salts, oxy fatty acids, paraffins, low molecular weight polyolefins, fatty acid amides, alkylene bis fatty acid amides, aliphatic ketones, fatty acid partial saponified esters, fatty acid lower alcohol esters, fatty acid polyvalents. Examples include alcohol esters, fatty acid polyglycol esters, and modified silicones. By blending these, a molded product excellent in mechanical properties, moldability, and heat resistance can be obtained.

Fatty acids having 6 to 40 carbon atoms are preferred. Specifically, oleic acid, stearic acid, lauric acid, hydroxystearic acid, behenic acid, arachidonic acid, linoleic acid, linolenic acid, ricinoleic acid, palmitic acid, montan Examples thereof include acids and mixtures thereof. The fatty acid metal salt is preferably an alkali (earth) metal salt of a fatty acid having 6 to 40 carbon atoms, and specific examples include calcium stearate, sodium montanate, and calcium montanate.
Examples of the oxy fatty acid include 1,2-oxysteric acid. Paraffin having 18 or more carbon atoms is preferable, and examples thereof include liquid paraffin, natural paraffin, microcrystalline wax, petrolactam and the like.

As the low molecular weight polyolefin, for example, those having a molecular weight of 5000 or less are preferable, and specific examples include polyethylene wax, maleic acid-modified polyethylene wax, oxidized type polyethylene wax, chlorinated polyethylene wax, and polypropylene wax. Fatty acid amides having 6 or more carbon atoms are preferred, and specific examples include oleic acid amide, erucic acid amide, and behenic acid amide.
The alkylene bis fatty acid amide is preferably one having 6 or more carbon atoms, and specifically includes methylene bis stearic acid amide, ethylene bis stearic acid amide, N, N-bis (2-hydroxyethyl) stearic acid amide and the like. As the aliphatic ketone, those having 6 or more carbon atoms are preferable, and examples thereof include higher aliphatic ketones.

Examples of the fatty acid partial saponified ester include a montanic acid partial saponified ester. Examples of the fatty acid lower alcohol ester include stearic acid ester, oleic acid ester, linoleic acid ester, linolenic acid ester, adipic acid ester, behenic acid ester, arachidonic acid ester, montanic acid ester, isostearic acid ester and the like.
Examples of fatty acid polyhydric alcohol esters include glycerol tristearate, glycerol distearate, glycerol monostearate, pentaerythritol tetrastearate, pentaerythritol tristearate, pentaerythritol dimyristate, pentaerythritol Examples include tall monostearate, pentaerythritol adipate stearate, sorbitan monobehenate and the like. Examples of fatty acid polyglycol esters include polyethylene glycol fatty acid esters, polytrimethylene glycol fatty acid esters, and polypropylene glycol fatty acid esters.

Examples of the modified silicone include polyether-modified silicone, higher fatty acid alkoxy-modified silicone, higher fatty acid-containing silicone, higher fatty acid ester-modified silicone, methacryl-modified silicone, and fluorine-modified silicone.
Of these, fatty acid, fatty acid metal salt, oxy fatty acid, fatty acid ester, fatty acid partial saponified ester, paraffin, low molecular weight polyolefin, fatty acid amide, and alkylene bis fatty acid amide are preferable, and fatty acid partial saponified ester and alkylene bis fatty acid amide are more preferable. Of these, montanic acid ester, montanic acid partially saponified ester, polyethylene wax, oxidized polyethylene wax, sorbitan fatty acid ester, erucic acid amide, and ethylene bisstearic acid amide are preferable, and montanic acid partially saponified ester and ethylene bisstearic acid amide are particularly preferable.
A mold release agent may be used by 1 type and may be used in combination of 2 or more type. The content of the release agent is preferably 0.01 to 3 parts by weight, more preferably 0.03 to 2 parts by weight, with respect to 100 parts by weight of the copolymerized polyethylene terephthalate.

<Manufacture of molded body>
The copolymerized polyethylene terephthalate of the present invention is usually obtained as a pellet, and a molded product can be produced by using various molding methods such as injection molding and extrusion molding using this as a raw material.
In the injection molding, not only a normal cold runner molding method but also a hot runner molding method is possible. In such injection molding, not only a normal molding method but also an injection compression molding, an injection press molding, a gas assist injection molding, a foam molding (including those by injection of a supercritical fluid), an insert molding, depending on the purpose as appropriate. A molded product can be obtained using an injection molding method such as in-mold coating molding, heat insulating mold molding, rapid heating / cooling mold molding, two-color molding, sandwich molding, and ultrahigh-speed injection molding. The advantages of these various molding methods are already widely known.
In extrusion molding, products such as various profile extrusion molded articles, sheets, and films can be obtained. For forming sheets and films, an inflation method, a calendar method, a casting method, or the like can also be used. It is also possible to form a heat-shrinkable tube by applying a specific stretching operation.

By using the copolymerized polyethylene terephthalate of the present invention for rotational molding or blow molding, it is possible to obtain a hollow molded product.
When the copolymerized polyethylene terephthalate of the present invention is processed into a molded body, for example, in the case of injection molding, it is preliminarily dried for 5 hours or more in a hot air dryer at 130 to 160 ° C., and then melted at a cylinder temperature of 260 to 300 ° C. It is preferable to mold by injection into a mold having a mold temperature of 20 to 60 ° C.

  If the predrying temperature is less than 130 ° C, the drying becomes insufficient, the resin may be decomposed by moisture remaining in the pellets, and the intrinsic viscosity may not be stable. If the predrying temperature is higher than 160 ° C, the pellets turn yellow. The appearance of the molded body may be impaired. If the cylinder temperature is less than 260 ° C, fluidity may be lowered or unmelted resin may be generated, and the appearance and physical properties may be impaired. If the cylinder temperature exceeds 300 ° C, the intrinsic viscosity of the molded product may not be stable due to resin decomposition. is there. If the mold temperature is less than 20 ° C., the fluidity is lowered, which is not preferable. If the mold temperature exceeds 60 ° C., the solidification time of the resin becomes long and the molding cycle becomes long.

  Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to these.

1. Production method of copolymerized polyethylene terephthalate Copolymerized polyethylene terephthalate was produced by the method shown in the production examples below. Moreover, the value of the intrinsic viscosity in a manufacture example was calculated | required by the following method.
(1) Intrinsic Viscosity (IV) Measurement Method 0.6 g of resin was dissolved in 50 ml of o-chlorophenol at 100 ° C. for 1 hour by heating and then cooled to room temperature. The viscosity of the resulting resin solution was determined to be Ostwald viscosity. Measurement was performed using a tube under a temperature condition of 35 ° C., and the intrinsic viscosity (IV) of the resin was determined from the obtained solution viscosity data.
(2) Production of polyethylene terephthalate

[Production Example 1: Copolyethylene terephthalate PET-1]
A mixed slurry composed of high-purity terephthalic acid, isophthalic acid and ethylene glycol, prepared in quantities so as to have the polymer composition shown in Table 1, is fed to the esterification reactor at a constant rate and increased to 0.3 MPa at 270 ° C. with stirring. The esterification reaction was carried out while applying nitrogen pressure and distilling off the generated water and ethylene glycol out of the system. The mixed slurry of the same weight was supplied to half of the obtained oligomer, and the esterification reaction was carried out while distilling off the generated water and ethylene glycol under normal pressure at 270 ° C. while stirring. The same operation was repeated 5 times to produce a polyester oligomer with stable quality.
Next, this polyester oligomer was transferred to a polycondensation reaction vessel, and while stirring, a germanium dioxide catalyst as a polycondensation catalyst was added so as to be 25 mmol% with respect to the total dicarboxylic acid component. Then, orthophosphoric acid was added as a stabilizer so that the phosphorus atom was 12.2 mmol% with respect to the total dicarboxylic acid component. Subsequently, the reaction temperature in the system is increased from 270 ° C. to 285 ° C., and the reaction pressure is gradually increased and reduced from normal pressure to 60 Pa, respectively. Went. The degree of progress of the polycondensation reaction was confirmed as a load on the stirring blade, and the reaction was terminated when the desired degree of polymerization was reached. Thereafter, the reaction product in the system was continuously extruded in a strand form from the discharge part, cooled and cut to obtain about 3 mm granular pellets. The obtained composition and physical properties are shown in Table 1.

[Production Examples 2 to 9: Copolymerized polyethylene terephthalate PET-2 to 9]
The procedure was the same as in Production Example 1 except that the quantities of high-purity terephthalic acid and isophthalic acid were changed so that the polymer composition shown in Table 1 was obtained. The results are shown in Table 1.

2. Low temperature storage test in vacuum blood collection tube Using the granular pellets obtained in Production Examples 1 to 9, the bottomed tube 2 was molded at the cylinder temperature and molding cycle shown in Table 2. Next, the plug 3 was inserted into the opening of the bottomed tube 2 and sealed in a sealed box whose pressure was reduced to 35 kPa. This was irradiated with 10 kGy of gamma rays to obtain a vacuum blood collection tube 1.
One of the metal needles was connected to the water tank, the other was pierced through the stopper 3 of the vacuum blood collection tube 1, and 8.5 mL of water was filled in the vacuum blood collection tube 1. Next, the vacuum blood collection tube 1 filled with water was set up vertically using a rack, stored in a freezer for 3 hours while placed on the rack, taken out to room temperature, and counted for leaking water due to breakage. In addition, the temperature in a freezer was set to -20 degreeC, -30 degreeC, -40 degreeC, and -80 degreeC, and the test was done for ten each level. The results are shown in Table 2.

<Examples 1-7>
Examples 1 to 7, in which the content ratio of terephthalic acid (component B-1) and isophthalic acid (component B-2) in the dicarboxylic acid are within the specified range of claim 1, are also stored at less than -30 ° C. Damage to the vacuum blood collection tube was suppressed, and it had excellent properties as a medical molded article.

<Comparative Example 1>
When PET-8 in which the content ratio of isophthalic acid (component B-2) in the dicarboxylic acid exceeds the upper limit of the prescribed range of claim 1, breakage frequently occurred during storage at less than -30 ° C.

<Comparative Example 2>
When PET-9 in which the content ratio of terephthalic acid (component B-1) in dicarboxylic acid was 100 mol%, breakage occurred frequently during storage at less than -30 ° C.

1. 1. Vacuum blood collection tube 2. Bottomed tube Plug

Claims (4)

  A copolymer polyethylene terephthalate comprising a glycol component (component A) and a dicarboxylic acid component (component B), wherein the glycol component is ethylene glycol (component A-1), and the dicarboxylic acid component is terephthalic acid (B- One component) 94-99 mol% and isophthalic acid (component B-2) 1-6 mol% is a dicarboxylic acid copolymerized polyethylene terephthalate obtained by molding and used at less than -30 ° C. Medical molded body.   The medical molded article according to claim 1, wherein the intrinsic viscosity of the copolymerized polyethylene terephthalate is 0.5 to 0.8 dl / g.   The medical molded body according to claim 1 or 2, wherein the medical molded body is a vacuum blood collection tube. The medical molded body according to any one of claims 1 to 3, which is molded by a molding method selected from the group consisting of injection molding, extrusion molding, thermoforming, and blow molding.

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