JPH08311275A - Resin composition for syringe - Google Patents

Abstract

PURPOSE: To obtain a resin compsn. for syringe which retains its excellent sliding properties and clarity even after being subjected to radiation sterilization. CONSTITUTION: This compsn. comprises a propylene-ethylene random copolymer having a haze of 50% or lower at a thickness of 1mm, a satd. fatty acid monoamide, and an ultraviolet absorber and/or an ultraviolet stabilizer and has a coefficient of static friction between the compsns. of 0.3 or lower and a coefficient of static friction between the compsns. after being irradiated with γ-rays of 0.4 or lower.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for a syringe, and more particularly to a resin composition for a syringe having excellent slidability and transparency even after radioactive sterilization.

[0002]

BACKGROUND OF THE INVENTION Polypropylene resins have been widely used in molding methods such as film molding and blow molding since they are excellent in heat resistance, chemical resistance and processability. Its applications also include medical instruments and scientific and laboratory instruments. However, when the polypropylene resin composition is used in a syringe, there is a problem that the slidability is not sufficient.

In order to impart slidability, secondary processing such as applying silicone oil to a molded product or coating another material having excellent slidability is performed. However, products coated with silicone oil are not preferable in terms of surface appearance and safety. Further, when the secondary processing such as fluororesin coating is performed after the molding, there is a problem that the working process becomes complicated and the manufacturing cost becomes high. Further, a method of adding a sliding agent such as oleic acid amide to the resin to impart slidability can be mentioned. However, a molded article obtained from such a resin composition has a remarkable slidability when irradiated with γ-rays. There is a problem of decrease.

Therefore, an object of the present invention is to provide a resin composition for a syringe which has excellent slidability and transparency even after radioactive sterilization treatment.

[0005]

As a result of earnest research in view of the above problems, the present inventors have found that by blending a specific compound with a polyolefin-based resin, a resin composition for a syringe having excellent slidability is obtained. The inventors have found that a product can be obtained, and completed the present invention.

That is, the resin composition for a syringe of the present invention has (a) a haze value of 50% when the thickness is 1 mm.
A propylene-ethylene random copolymer which is the following,
(b) saturated fatty acid monoamide, and (c) UV absorber and / or
Alternatively, a resin composition comprising an ultraviolet stabilizer, wherein the static friction coefficients of the resin compositions are 0.3 or less, and the static friction coefficients of the resin compositions after γ-ray irradiation are 0.
It is characterized by being 4 or less.

The present invention will be described in detail below. [1] Components of Resin Composition for Syringe (A) Polyolefin Resin The polyolefin resin used in the present invention is propylene-
The ethylene random copolymer is a homopolymer or a mixture thereof with another polyolefin.

(A) In case of propylene-ethylene random copolymer alone The propylene-ethylene random copolymer is a copolymer obtained by coexisting propylene and ethylene, and the ethylene content of the copolymer is 0. 0.1 to 10% by weight is preferable, and 0.5 to 5% by weight is particularly preferable. If the ethylene content is less than 0.1% by weight, the randomness in the copolymer will be lost, while if it exceeds 10% by weight, the mechanical strength will decrease.

The haze value (ASTM D when the thickness of the propylene-ethylene random copolymer is 1 mm)
1003-61) is 50% or less, preferably 40
% Or less, more preferably 20% or less, and it has transparency. Furthermore, the melt flow rate of propylene-ethylene random copolymer (MFR, 230 ° C,
(Measured at 2.16 kg) is preferably 0.1 to 100 g / 10 minutes, and particularly preferably 0.5 to 80 g / 10 minutes. M
When FR is less than 0.1 g / 10 minutes, moldability is low,
On the other hand, if it exceeds 100 g / 10 minutes, the mechanical strength will decrease.

The method for producing the propylene-ethylene random copolymer is not particularly limited, but it can be obtained by applying a gas phase polymerization method in which propylene and ethylene are simultaneously supplied in the presence of a stereoregular catalyst. As the stereoregular catalyst, titanium trichloride, titanium tetrachloride, titanium halide compounds such as trichloroethoxy titanium, transition metal components such as a contact product of the titanium halide compound and a magnesium compound represented by magnesium halide. Alkyl aluminum compounds or their two-component catalysts with halides, hydrides, alkoxides and other organometallic components, and electron donating compounds containing nitrogen, carbon, phosphorus, sulfur, oxygen, silicon, etc. There are also three-component catalysts.

(B) Mixture When a mixture of propylene-ethylene random copolymer and other polyolefin is used as the polyolefin resin, the content of the propylene-ethylene random copolymer is 50% or more. , Preferably 60% or more. If the proportion of the propylene-ethylene random copolymer is less than 50%, the mechanical strength will decrease. The polyolefin to be mixed has a haze value (thickness: 1 mm) of 50% or less, preferably 40% or less, more preferably 20% or less, and has transparency.

The other polyolefin to be mixed with the propylene-ethylene random copolymer is not particularly limited, but it is preferable to use propylene homopolymer, high density polyethylene, low density polyethylene, or a mixture thereof.

When a propylene homopolymer is used, the MFR is 0.1 to 10 from the viewpoint of moldability and mechanical strength.
0 g / 10 minutes is preferable, and 0.5 to 80 g / 10 minutes is particularly preferable. The method for producing the propylene homopolymer is not particularly limited, but a polymerization method using a stereoregular catalyst in the presence of a stereoregular catalyst is preferable. As the stereoregular catalyst, titanium trichloride, titanium tetrachloride, titanium halide compounds such as trichloroethoxy titanium, transition metal components such as a contact product of the titanium halide compound and a magnesium compound represented by magnesium halide. Alkyl aluminum compounds or their two-component catalysts with halides, hydrides, alkoxides and other organometallic components, and to these components an electron donating compound containing nitrogen, carbon, phosphorus, sulfur, oxygen, silicon, etc. is added. Another example is a three-component catalyst.

High density polyethylene has a density of 0.940.
g / cm ³ or more, preferably 0.945 to 0.960 g
/ Cm ³ is a polymer containing a repeating unit derived from ethylene as a main polymerization component. High-density polyethylene can be obtained, for example, by polymerizing ethylene by a low pressure method in the presence of a Ziegler catalyst.

Low density polyethylene has a density of 0.940.
It is a polymer whose main polymerization component is a repeating unit derived from ethylene of less than g / cm ³ , preferably 0.935 g / cm ³ or less. The low density polyethylene can be obtained by polymerizing ethylene by a medium / high pressure method in the presence of a Ziegler catalyst.

The melt index (MI, 190 ° C.,
The measurement (measured at 2.16 kg) is preferably 5 to 30 g / 10 minutes, and particularly preferably 8 to 20 g / 10 minutes.

(B) Saturated Fatty Acid Monoamide The saturated fatty acid monoamide used in the present invention is preferably a saturated fatty acid monoamide having a fatty acid moiety having 8 to 40 carbon atoms, and these may be used alone or in combination. When unsaturated fatty acid monoamides such as oleic acid amide and erucic acid amide are used, the slidability is significantly reduced after irradiation with radiation and heat treatment. The melting point of the saturated fatty acid monoamide is preferably 85 ° C. or higher, and 9
0-110 degreeC is more preferable. The molecular weight is preferably 180 or more, more preferably 190 to 350. However, when using two or more saturated fatty acid monoamides,
The average molecular weight is used as the molecular weight. Examples of such saturated fatty acid monoamide include palmitic acid amide, stearic acid amide, and behenic acid amide.

(C) UV Absorber and UV Stabilizer The UV absorbers used in the present invention include benzophenone-based, benzotriazole-based, salicylate-based, substituted acrylonitrile-based, various metal salts, metal chelates, and triazine-based UV-absorbing agents. Agents are preferred. For example, 2-hydroxy-
4-n-octoxy-benzophenone, 2- (2'-hydroxy-3 ', 5'-di-t-butyl-phenyl)-
5-chlorobenzotriazole etc. are mentioned.

The UV stabilizer is preferably a hindered amine-based light / weather-resistant stabilizer, and particularly preferably a hindered amine-based light / weather-resistant stabilizer having a piperidine structure.
For example, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, bis- (2,2,6,6-tetramethyl-4-N-methylpiperidyl) sebacate, di-
(1,2,2,6,6-pentamethyl-4-piperidyl) -2-n-butyl-2- (3,5-di-t-butyl-4-hydroxybenzyl) malonate, bis- (2,2
2,6,6-Tetramethyl-4-carbonyloxypiperidino) -p-dimethylbenzyl, 2,2,4,4-tetramethyl-7-oxa-3,20-diaza-21-oxo-dispiro [ 5.1.9.19] Heneicosane, bis- (2,2,6,6-tetramethyl-4-piperidyl) sebacate, dimethyl succinate 2- (4-hydroxy-2,2,6,6-) Tetramethyl-1-piperidyl) ethanol condensate and poly [{6- (1,1,
3,3-Tetramethylbutyl) imino} -1,3,5-
Triazine-2,4-diyl- {4- (2,2,6,6
-Tetramethylpiperidyl) imino} -hexamethylene- {4- (2,2,6,6-tetramethylpiperidyl)
Imino}]. Among these, especially bis-
(2,2,6,6-Tetramethyl-4-piperidyl) sebacate and dimethylsuccinate.2- (4-hydroxy-2,2,6,6-tetramethyl-1-piperidyl) ethanol condensate are preferred. .

(D) Other Additives The resin composition for a syringe of the present invention contains a phosphorus-based antioxidant, a phenol-based antioxidant, a sulfur-based antioxidant, a heat stabilizer, a neutralizing agent, and a sorbitol-based agent, depending on the application. An organoaluminum-based or phosphate-based nucleating agent, a pigment, a dye, a filler, an antistatic agent and the like can be added within a range that does not impair the object of the present invention.

[2] Mixing ratio The mixing ratio of each component is not particularly limited as long as the static friction coefficient of the resin composition is within the range described below, but saturated fatty acid is added to 100 parts by weight of the polyolefin resin. The monoamide is preferably 0.01 to 3.0 parts by weight, more preferably 0.05 to 2.0 parts by weight. Further, the ultraviolet absorber and / or the ultraviolet stabilizer is 0.01 to 3.
It is preferably 0 part by weight, more preferably 0.03 to 1.0 part by weight.

The saturated fatty acid monoamide content is 0.01
If it is less than part by weight, the effect of improving the slidability is not sufficient, while if it exceeds 3.0 parts by weight, the molded product becomes sticky and the surface appearance becomes poor. If the amount of the ultraviolet absorber and / or the ultraviolet stabilizer is less than 0.01 parts by weight, the weather resistance is insufficient, while if it exceeds 3.0 parts by weight, the corresponding effect is not improved.

[3] Physical Properties of Resin Composition for Syringe The static friction coefficient between the resin compositions for syringe prepared by blending the above-mentioned respective components is 0.3 or less, preferably 0.2 or less. The static friction coefficient between the resin compositions after irradiation with γ-rays of 2.5 megarad is 0.4 or less, preferably 0.3 or less, and more preferably 0.2 or less. The coefficient of static friction between the resin compositions is 80 mm x 8
Two sheets of 0mm x 1mm are piled up, a weight of 200g is put on the sheet, and the upper sheet is 50mm /
It can be obtained by measuring the tensile load at the start of movement when the sheet is pulled and moved in the horizontal direction at a speed of minutes.

[4] Method for producing polypropylene resin composition for syringes The polypropylene resin composition for syringes of the present invention is prepared by mixing the above components using a Henschel mixer, a super mixer, a ribbon blender, etc. It can be obtained by melt-kneading in a temperature range of 160 to 250 ° C. with a twin-screw extruder, Banbury mixer, Brabender, roll or the like.

[0025]

EXAMPLES The present invention will be described in detail with reference to the following examples and comparative examples, but the present invention is not limited thereto.

Examples 1 and 2, Comparative Examples 1 and 2 1. Raw material (A) Polyolefin (PO) -based resin-RPP1: Ethylene-propylene random copolymer MFR: 30 g / 10 minutes (230 ° C, load 2.16 kg)
Ethylene content: 3 wt% haze value: 41% (according to ASTM D1003-61) RPP2: ethylene-propylene random copolymer MFR: 30 g / 10 min ethylene content: 4 wt% haze value: 36 % -PP: Propylene homopolymer MFR: 30 g / 10 min Haze value: 58% (B) Fatty acid amide-SA: Stearic acid amide-BA: Behenic acid amide-OA: Oleic acid amide-EA: Erucic acid amide (C ) Ultraviolet absorber and / or ultraviolet stabilizer (UV) -T-622 LD: Hindered amine compound (Tinuvin
622 LD, Ciba Geigy) (D) Other additives ・ MARK2112: Phosphorus antioxidant (Asahi Denka Kogyo Co., Ltd.)
IR1010: Phenolic antioxidant (Irganox)
1010, manufactured by Ciba Geigy) ・ Gelol MD: 1,3,2,4-di (p-methylbenzylidene) sorbitol (manufactured by Shin Nippon Rika Co., Ltd.) ・ Ca-St: calcium stearate

2. Kneading and molding method The above raw materials were blended in the proportions shown in Table 1, dry-blended using a super mixer, and then melt-kneaded using a 50 mmφ single-screw extruder. Extruded from the die at a die outlet temperature of 210 ° C, and the obtained pellets were
Injection molding was carried out at a resin temperature of 230 ° C., an injection pressure of 900 kg / cm ² and a mold temperature of 60 ° C. to prepare a sheet having a thickness of 1 mm.

3. Physical property measurement A test piece (thickness: 1 mm) was prepared from the obtained sheet,
The haze value (%) was measured according to ASTM D1003-61. In addition, two sheets of 80 mm x 80 mm x 1 mm are superposed, a weight of 200 g is placed on the sheets, and the upper sheet is pulled by moving horizontally at a speed of 50 mm / min. The load was measured and the static friction coefficient was determined. The coefficient of static friction was determined for the same sheet irradiated with 2.5 megarads of γ-rays. The results of these measurements are shown in Table 1 below.

Table 1 No. Example 1 Example 2 Comparative Example 1 Comparative Example 2 Composition (parts by weight ) (A) PO-based resin RPP1 100 -100 100 RPP2 70 70 PP 30 30 30 (B) Fatty acid amide SA 0.2 ─ BA ─ 0.2 ─ OA ─ ─ 0.2 ─ EA ─ ─ ─ 0.2 (C) UV T-622LD 0.05 0.05 0.05 0.1 (D) Additive MARK2112 0.1 0.1 0.1 0.1 IR1010 0.1 0.1 0.1 0.1 Gelol MD 0.2 0.2 0.2 0.2 Ca-St 0.1 0.1 0.1 0.1 Physical property haze value (%) 10.7 10.9 10.5 10.8 Static friction coefficient Untreated 0.12 0.14 0.08 0.08 After gamma ray irradiation 0.14 0.15 0.65 0.65

As is clear from Table 1, Examples 1 and 2
The resin composition for a syringe has a small coefficient of static friction even after γ-ray irradiation and is excellent in slidability. On the other hand, the resin compositions for syringes of Comparative Examples 1 and 2 have a large static friction coefficient after γ-ray irradiation and a remarkable decrease in slidability as compared with the case where they are not treated.

[0031]

The resin composition for a syringe of the present invention comprises a polyolefin resin containing 50% or more of a propylene-ethylene random copolymer having a haze value of 50% or less when the thickness is 1 mm, Since it contains a saturated fatty acid monoamide and an ultraviolet absorber and / or an ultraviolet stabilizer, it is remarkably excellent in slidability and transparency even after γ-ray irradiation.

Claims (2)

[Claims] 1. A propylene-ethylene random copolymer having (a) a haze value of 50% or less when the thickness is 1 mm, (b) a saturated fatty acid monoamide, (c) an ultraviolet absorber and / or A resin composition comprising an ultraviolet stabilizer, wherein the coefficient of static friction between resin compositions is 0.3 or less, and the coefficient of static friction between resin compositions after γ-ray irradiation is 0.4 or less. A resin composition for a syringe characterized by being present. 2. A polyolefin resin containing (a) 50% or more of a propylene-ethylene random copolymer and having a haze value of 50% or less when the thickness is 1 mm,
(b) saturated fatty acid monoamide, and (c) UV absorber and / or
Alternatively, a resin composition comprising an ultraviolet stabilizer, wherein the static friction coefficients of the resin compositions are 0.3 or less, and the static friction coefficients of the resin compositions after γ-ray irradiation are 0.
A resin composition for a syringe, which is 4 or less.