JP2002226649A - Outer cylinder for syringe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an outer cylinder for a syringe which is excellent in rigidity and especially in impact resistance while maintaining transparency. SOLUTION: This outer cylinder for a syringe is obtained by molding a resin composition which contains in a specific ratio a specified ethylene- propylene random copolymer and an ethylene-α-olefin copolymer polymerized with use of a specific metallocene catalyst, furthermore, may contain in a specific ratio a specified polypropylene homopolymer and/or a specified polyethylene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a syringe barrel, and more particularly, to a syringe barrel which is superior in rigidity and impact resistance to conventional products while maintaining transparency.

[0002]

2. Description of the Related Art The production cost of medical instruments such as syringe barrels has been reduced compared to the prior art due to the achievement of thinner walls. However, in practical use, the medical device is often kept cool while being filled with a drug or a drug solution, and there is a possibility that an impact is applied in that state. Therefore, the demand for improving the impact resistance of medical instruments, particularly syringe barrels, is becoming very large. Generally, it is possible to improve the impact resistance by using a propylene / ethylene random copolymer or a propylene / ethylene block copolymer having an increased ethylene content as a base material for a syringe barrel. is there. However, a syringe barrel using a propylene / ethylene random copolymer having a high ethylene content as a base material may have a markedly reduced rigidity, which may impair workability when used as a syringe. In the syringe barrel using the propylene / ethylene block copolymer as a base material, the transparency is extremely deteriorated, and the visibility of the contents may be impaired.

For example, JP-A-61-159439 discloses (a) a propylene homopolymer or an ethylene / propylene random copolymer having an ethylene content of 3% by weight or less, (b) an ethylene / propylene random copolymer having an ethylene content of 4 to 15%. % Of ethylene-propylene random copolymer and (c) an organic peroxide, wherein the ethylene content in the total amount of these resins is 1.5 to 4.5% by weight, and A propylene polymer composition in which the mixing ratio of the organic peroxide is 0.001 to 0.25 parts by weight based on 100 parts by weight in total and the melt flow index is 15 g / 10 minutes or more is disclosed. However, the composition disclosed in this publication does not have sufficient transparency, and does not have a sufficient effect of lowering the tensile elastic modulus and impact resistance after γ-ray irradiation. Japanese Patent Application Laid-Open No. 60-215047 discloses a melt flow rate (hereinafter, referred to as a melt flow rate) in the presence of a radical generator.
Abbreviated as "MFR". ) Reduced from 0.05 to 10 g / 10 min to 10 to 100 g / 10 min, 5 to 95% by weight of propylene homopolymer block and ethylene content of 2-1.
100 parts by weight of a propylene-based block copolymer containing 5 to 5% by weight of a propylene / ethylene random copolymer block of 5% by weight;
A polypropylene composition comprising from 0.5 to 0.5 parts by weight is disclosed. However, since the composition disclosed in this publication uses a block copolymer of a propylene homopolymer and a propylene / ethylene random copolymer, it has sufficient transparency for use in medical devices such as syringes. There is a problem of not having. Accordingly, there has been a strong demand for the development of a syringe barrel that is superior in rigidity and significantly superior in impact resistance to conventional products while maintaining transparency.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a syringe barrel which is excellent in rigidity while maintaining transparency, and is particularly excellent in impact resistance.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have found that ethylene / ethylene polymerized using a specific propylene / ethylene random copolymer and a specific metallocene catalyst. Resin composition (1) containing α-olefin copolymer at a specific ratio, and resin containing three components obtained by adding a specific propylene homopolymer to the resin composition (1) at a specific ratio Composition (2),
A resin composition (3) containing, at a specific ratio, three components obtained by further adding a specific polyethylene to the resin composition (1);
In addition, a syringe barrel obtained by molding a resin composition (4) containing a specific ratio of four components obtained by further adding a specific propylene homopolymer and polyethylene to the resin composition (1) has improved transparency. The present invention was found to be excellent in rigidity, and particularly excellent in impact resistance, while maintaining, and completed the present invention.

That is, according to the first aspect of the present invention,
(A) MFR (230 ° C., 2.16 kg load) is 0.5
-100 g / 10 min and ethylene content of 2.0
-5.0% by weight of propylene / ethylene random copolymer: 85-99.8 parts by weight and (B) MFR (1
Ethylene / α-olefin copolymer polymerized using a metallocene catalyst having a temperature of 90 ° C. and a load of 2.16 kg) of 5 to 50 g / 10 min and a density of 0.860 to 0.913 g / cm ³ : 0 A syringe barrel formed by molding a resin composition containing 0.2 to 15 parts by weight.

Further, according to the invention of Brother 2 of the present invention,
(A) MFR (230 ° C., 2.16 kg load) is 0.5
-100 g / 10 min and ethylene content of 2.0
-5.0% by weight of a propylene / ethylene random copolymer: 50-98.8 parts by weight, (B) MFR (190
° C., 2.16 kg load) a 5 to 50 g / 10 min, an ethylene · alpha-olefin copolymer density is polymerized by using a metallocene catalyst is 0.860~0.913g / cm ^3: 0. 2 to 15 parts by weight and (C) MFR
(230 ° C., 2.16 kg load) 0.5 to 100 g /
A syringe barrel formed by molding a resin composition containing 1 to 49 parts by weight of a propylene homopolymer for 10 minutes is provided.

According to a third aspect of the present invention,
(A) MFR (230 ° C., 2.16 kg load) is 0.5
-100 g / 10 min and ethylene content of 2.0
-5.0% by weight of a propylene / ethylene random copolymer: 85-99.7 parts by weight, (B) MFR (190
° C., 2.16 kg load) a 5 to 50 g / 10 min, an ethylene · alpha-olefin copolymer density is polymerized by using a metallocene catalyst is 0.860~0.913g / cm ^3: 0. 2 to 15 parts by weight and (D) MFR
(190 ° C., 2.16 kg load) 10 to 50 g / 10
Min and a density of 0.940 to 0.980 g / cm ³
Polyethylene: 0.1 to 1.0 parts by weight of a resin composition is provided.

Further, according to a fourth aspect of the present invention,
(A) MFR (230 ° C., 2.16 kg load) is 0.5
-100 g / 10 min and ethylene content of 2.0
Propylene / ethylene random copolymer in an amount of 50 to 98.7 parts by weight, and (B) MFR (190
° C., 2.16 kg load) a 5 to 50 g / 10 min, an ethylene · alpha-olefin copolymer density is polymerized by using a metallocene catalyst is 0.860~0.913g / cm ^3: 0. 2 to 15 parts by weight, (C) MFR (23
(0 ° C., 2.16 kg load) 0.5 to 100 g / 10 min propylene homopolymer: 1 to 49 parts by weight and (D)
MFR (190 ° C, 2.16 kg load) is 10 to 50 g
/ 10 min and a density of 0.940 to 0.980 g /
Provided is a syringe barrel formed by molding a resin composition containing 0.1 to 1.0 parts by weight of polyethylene having a cm ³ .

[0010] According to a fifth aspect of the present invention, the first aspect is provided.
In any one of the fourth to fourth inventions, there is provided a syringe barrel formed by treating the resin composition with a peroxide compound to reduce the molecular weight and then molding the same.

Further, according to the sixth aspect of the present invention, the first aspect is provided.
In any one of the fifth to fifth inventions, there is provided a syringe barrel further subjected to radiation treatment.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a syringe barrel of the present invention will be described in detail.

The resin used in the present invention will be described below. [I] Resin (A) Propylene / ethylene random copolymer (A) The propylene / ethylene random copolymer used in the present invention has a M measured at 230 ° C. under a load of 2.16 kg.
FR is 0.5 to 100 g / 10 min, preferably 3.0.
５０50 g / 10 min, more preferably 4.5 to 35 g / 1
0 minutes. If the MFR is less than 0.5 g / 10 minutes, the moldability is poor, and the width of the depletion to compensate for the increase is large, which causes poor formation such as threading of the gate portion during molding of the outer cylinder. . Conversely, the MFR is 100 g / 10
If the composition exceeds minutes, even if the composition is adjusted, physical properties such as impact resistance cannot be satisfied.

The ethylene content in the (A) propylene / ethylene random copolymer used in the present invention is as follows:
2.0 to 5.0% by weight. When the ethylene content in the propylene / ethylene random copolymer is less than 2.0% by weight, sufficient impact resistance cannot be obtained. On the other hand, when the ethylene content exceeds 5.0% by weight, sufficient rigidity is not obtained. Can not be obtained. Further, the ethylene content in the (A) propylene / ethylene random copolymer used in the resin composition (1) and the resin composition (3) described below is preferably 2.
It is 1 to 4.2% by weight, more preferably 2.4 to 3.5% by weight, and (A) propylene / ethylene random used for the resin composition (2) and the resin composition (4) described later. The ethylene content in the polymer is preferably 2.5
-4.8% by weight, more preferably 2.8-4.5% by weight
It is.

The (A) propylene / ethylene random copolymer is produced by, for example, slurry polymerization, gas phase polymerization or bulk polymerization using a highly stereoregular catalyst. As the polymerization method, any of a batch polymerization method and a continuous polymerization method can be adopted, but the continuous polymerization is preferable from the viewpoint of productivity. As the highly stereoregular catalyst, for example, a catalyst obtained by combining an organic aluminum compound component with a solid component formed by contacting magnesium tetrachloride, titanium tetrachloride, an organic acid halide and an organic silicon compound can be used.

(B) Ethylene / α-olefin copolymer polymerized using a metallocene catalyst The (B) ethylene / α-olefin copolymer polymerized using a metallocene catalyst used in the present invention is composed of ethylene and carbon number. It is a copolymer with 3 to 12 α-olefins. The α-olefin having 3 to 12 carbon atoms may be one kind or two or more kinds. (B) the ethylene / α-olefin copolymer polymerized using a metallocene catalyst,
The MFR measured at 0 ° C. under a load of 2.16 kg is 5 to 50.
g / 10 minutes, preferably 6 to 35 g / 10 minutes, more preferably 8 to 25 g / 10 minutes. MFR is 5g / 10
If it is less than minutes, dispersion in the polypropylene component becomes difficult, and it is difficult to improve transparency. Conversely, if the MFR exceeds 50 g / 10 minutes, a sufficient impact resistance improving effect cannot be obtained.

The density of the ethylene / α-olefin copolymer (B) polymerized using the metallocene catalyst is as follows:
0.860 to 0.913 g / cm ³ , preferably 0.8
80 to 0.910 g / cm ³ , more preferably 0.89
0 to 0.905 g / cm ³ . The density is 0.860
An ethylene / α-olefin copolymer polymerized using a metallocene catalyst of less than g / cm ³ significantly deteriorates transparency and rigidity. On the other hand, ethylene • α-polymerized using a metallocene catalyst having a density exceeding 0.913 g / cm ³
In this system, the olefin copolymer does not have a sufficient impact resistance improving effect, and even impairs transparency.

The ethylene / α-olefin copolymer (B) polymerized using the metallocene catalyst used in the present invention is:
It is preferable that two or more crystallization peak temperatures (Tc) are observed in a temperature-lowering thermogram of 10 ° C./min by a differential scanning calorimeter (DSC). The difference between the high temperature side (Tc2: high temperature crystallization peak temperature) and the low temperature side (Tcl: low temperature crystallization peak temperature) of the crystallization peak temperature (Tc) is preferably 5 ° C. or more, more preferably 8 ° C. or more. is there. Further, Tc2 is preferably 110 ° C. or lower, more preferably 100 ° C. or lower, and desirably 90 ° C. or lower, and Tcl is preferably 70 ° C. or lower, more preferably 60 ° C. or lower, and desirably 50 ° C. or lower.

The α-olefin of the ethylene / α-olefin copolymer polymerized by using the metallocene catalyst (B) of the present invention
For the temperature Tl = −1097 + c × 2.3 + d × 1270 expressed by the carbon number (c) and the density (d) of the olefin, the total elution amount by the temperature rising melt separation (TREF) at the temperature T2 = (Tl + 30) or more is It is preferably at least 5% by weight of the total eluted amount.

The temperature rise elution fractionation (TREF: Te
mperture RisingElution F
measurement) is described in “Journal o
fApplied Po1ymer Science,
Vol. 26, Nos. 4217-4231 (1981) "and" Principles of Polymers 2PIC09 (1985) ". First, a polymer to be measured is completely dissolved in a solvent. Thereafter, cooling is performed to form a thin polymer layer on the surface of the inert carrier. Such a polymer layer is formed such that an easily crystallizable material is formed on the inner side (closer to the surface of the inert carrier), and a hardly crystallizable material is formed on the outer side. Next, when the temperature is continuously or stepwise increased, in the low temperature stage,
The polymer is eluted from the amorphous portion in the target polymer composition, that is, the polymer having a short branching degree with a high degree of branching. The chain is eluted and the measurement is completed. By detecting the concentration of the eluted component at such a temperature, the composition distribution of the polymer can be seen from a graph drawn based on the amount of the eluted and the elution temperature.

(C) Propylene homopolymer (C) The propylene homopolymer used in the present invention is 23
The MFR measured at 0 ° C. under a load of 2.16 kg is 0.5 to
100 g / 10 min, preferably 3.0 to 50 g / 10
Min, more preferably 4.5 to 35 g / 10 min. M
When the FR is less than 0.5 g / 10 minutes, good moldability cannot be obtained as it is, and the economy is impaired in terms of degradation. Conversely, when the MFR exceeds 100 g / 10 minutes, the impact resistance of the outer cylinder molded product is impaired.

(D) Polyethylene The polyethylene (D) used in the present invention is a homopolymer of ethylene or a copolymer containing an α-olefin having 3 to 12 carbon atoms as a copolymer component. 2.16
MFR measured under a kg load is 10 to 50 g / 10 min,
Preferably 13-40 g / 10 min, more preferably 15
３０30 g / 10 min. If the MFR is less than 10 g / 10 minutes, transparency may be deteriorated due to poor dispersion or the like. Conversely, those having an MFR of more than 50 g / 10 minutes do not contribute to the desired improvement of the physical properties in the present system, and may impair the moldability.

The density of the polyethylene (D) is as follows:
0.940 to 0.980 g / cm ³ , preferably 0.9
47 to 0.969 g / cm ³ , more preferably 0.95
1 to 0.963 g / cm ³ . The density is 0.940
Polyethylene of less than g / cm ³ has insufficient nucleating agent properties, and does not have a sufficient effect of improving physical properties. On the other hand, the density is 0.98
Polyethylene exceeding 0 g / cm ³ may impair the impact resistance.

Next, the resin composition used in the present invention will be described below. [II] Resin composition (i) Resin composition (1) The resin composition (1) of the present invention comprises (A) 85 to 99.8 parts by weight, preferably 86 to 96 parts by weight of a propylene / ethylene random copolymer. Parts by weight, more preferably 89 to 94 parts by weight, and (B) 0.2 to 15 parts by weight, preferably 4 to 14 parts by weight, more preferably 4 to 14 parts by weight of the ethylene / α-olefin copolymer polymerized using the metallocene catalyst. Contains 6 to 11 parts by weight. When the content of (A) the propylene / ethylene random copolymer is less than 85 parts by weight, ((B) the content of the ethylene / α-olefin copolymer polymerized using the metallocene catalyst exceeds 15 parts by weight) ), The rigidity is insufficient, and the moldability may be poor. On the other hand, when the content of (A) the propylene / ethylene random copolymer exceeds 99.8 parts by weight, the content of (B) the ethylene / α-olefin copolymer polymerized by using the metallocene catalyst becomes 0.2%. If the amount is less than 10 parts by weight), it becomes impossible to sufficiently improve the impact resistance.

(Ii) Resin composition (2) The resin composition (2) of the present invention comprises (A) 50 to 98.8 parts by weight, preferably 53 to 80 parts by weight of a propylene / ethylene random copolymer, More preferably, 55 to 75 parts by weight of (B) ethylene polymerized using a metallocene catalyst.
0.2 to 15 parts by weight of the α-olefin copolymer, preferably 4 to 14 parts by weight, more preferably 6 to 11 parts by weight,
And (C) 1 to 49 parts by weight of a propylene homopolymer,
Preferably from 16 to 45 parts by weight, more preferably from 20 to 4 parts by weight.
0 parts by weight. The resin composition (2) is obtained by further improving the rigidity of the resin composition (1), and comprises (C)
When the content of the propylene homopolymer is less than 1 part by weight, the effect of improving rigidity is not recognized. On the other hand, when the content of the (C) propylene homopolymer exceeds 49 parts by weight, sufficient impact resistance is obtained. Can not be obtained.

(Iii) Resin composition (3) The resin composition (3) of the present invention comprises (A) 85 to 99.7 parts by weight, preferably 85 to 96 parts by weight of propylene / ethylene random copolymer, More preferably, 88 to 94 parts by weight of (B) ethylene polymerized using a metallocene catalyst.
0.2 to 15 parts by weight of the α-olefin copolymer, preferably 4 to 15 parts by weight, more preferably 6 to 12 parts by weight,
And (D) 0.1 to 1.0 part by weight of polyethylene, preferably 0.2 to 0.8 part by weight, more preferably 0.3 to 1.0 part by weight.
-0.7 parts by weight. The resin composition (3) further improves the transparency and moldability of the resin composition (1). If the content of (D) polyethylene is less than 0.1 part by weight, the transparency is improved. On the other hand, if the content of (D) polyethylene exceeds 1.0 part by weight, the transparency may be gradually deteriorated, and the impact resistance may be further deteriorated.

(Iv) Resin composition (4) The resin composition (4) of the present invention comprises (A) 50 to 98.7 parts by weight, preferably 53 to 80 parts by weight of a propylene / ethylene random copolymer, More preferably, 55 to 75 parts by weight of (B) ethylene polymerized using a metallocene catalyst.
0.2 to 15 parts by weight of the α-olefin copolymer, preferably 4 to 14 parts by weight, more preferably 6 to 11 parts by weight,
(C) 1 to 49 parts by weight, preferably 16 to 45 parts by weight, more preferably 20 to 40 parts by weight of propylene homopolymer and 0.1 to 1.0 part by weight of (D) polyethylene,
Preferably 0.2 to 0.8 parts by weight, more preferably 0.1 to 0.8 parts by weight.
It contains 3 to 0.7 parts by weight. The resin composition (4) is a composition in which the rigidity, transparency, and moldability of the resin composition (1) are further improved, and the content of the (C) propylene homopolymer is less than 1 part by weight. If there is, the effect of improving rigidity is not recognized, while if the content of (C) propylene homopolymer exceeds 49 parts by weight, sufficient impact resistance cannot be obtained. When the content of the polyethylene (D) is less than 0.1 part by weight, the effect of improving transparency and moldability is not exhibited, while the content of the polyethylene (D) is not more than 1.
If the amount exceeds 0 parts by weight, transparency may gradually deteriorate, and impact resistance may further deteriorate.

(V) Additives The resin compositions (1) to (4) used in the present invention may optionally contain other additional components as long as the effects of the present invention are not significantly impaired. Such additional components include resin additives used in ordinary polyolefin resins, for example, phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, neutralizers, light stabilizers, ultraviolet absorbers, Nucleating agents, transparent nucleating agents, lubricants, slip agents, antistatic agents, flame retardants, metal deactivators, fillers and the like.
The amount of these additional components is generally 0.001 to 2 with respect to 100 parts by weight of the resin compositions (1) to (4).
The amount is about part by weight, preferably about 0.01 to 0.8 part by weight.

[III] Production of resin composition and syringe barrel (i) Kneading / granulating The resin composition for a syringe barrel of the present invention (resin composition (1)
To (4)) are the above components, and if necessary, lacquer additives are blended in the above proportions to form a single-screw extruder, a twin-screw extruder,
A method of kneading and granulating using an ordinary kneading machine such as a Banbury mixer, a roll mixer, a Brabender plastograph, a kneader, or a kneaded material while stirring and kneading with a high-speed rotary stirring mixer such as a super mixer or a Henschel mixer. And then granulating with an extruder, so-called stirring kneading granulation method or the like.

In this case, it is preferable to select a kneading / granulating method capable of improving the dispersion of each component. Usually, the mixture is stirred and kneaded by a high-speed rotary stirring mixer (Japanese Patent Application Laid-Open No.
Kneading and granulation are performed using a stirring granulation method in which the kneaded material is granulated by another granulator, or a single-screw or twin-screw extruder. In the kneading / granulation, the compound of each of the above components may be kneaded at the same time, or the components may be divided and kneaded / granulated in order to improve the performance.

(Ii) Peroxide Compound Treatment Preferred MFR of the resin composition for a syringe barrel of the present invention
The range is about 25 to 100 g / 10 minutes. In general,
If the MFR is less than 25 g / 10 minutes, the high-speed moldability is not sufficient, and the impact resistance after γ-ray irradiation is not sufficient.
On the other hand, when it exceeds 100 g / 10 minutes, impact resistance is reduced, skin layer thickness and rigidity are reduced, and high-speed moldability cannot be achieved. For this reason, it is preferable to use the resin composition for a syringe barrel of the present invention in which the molecular weight of the resin composition has been reduced by a treatment using a peroxide compound as a radical generator. The reduction of the molecular weight is carried out in a usual manner, for example, by melt-kneading the resin composition in an extruder at 200 to 280 ° C. for 1 to 3 minutes in the presence of a peroxide compound.

Specific examples of the peroxide compound include:
Methyl ethyl ketone peroxide, t-butyl peroxyisopropyl carbonate, dicumyl peroxide,
Cumene hydroperoxide, 2,5-dimethyl-2,5
-Di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane
3, di-t-butyl peroxyphthalate and the like. The amount of the peroxide compound used is appropriately selected so that the resin composition has a desired MFR.
Used in a proportion of 1 part by weight.

(Iii) Molding of syringe barrel The syringe barrel of the present invention comprises the above resin composition (1) to
The pellet (4) is manufactured by molding by an injection molding method (including a gas injection molding method) or an injection compression molding method (injection press).

(Iv) Radiation treatment The syringe barrel of the present invention is subjected to radiation treatment, particularly γ-irradiation, after molding, after appropriate sealing and packaging, for the purpose of ensuring hygiene when used. Is preferred.
The γ-ray irradiation is usually performed so that the total irradiation amount is about 20 KGy.

[0035]

EXAMPLES The present invention will be specifically described with reference to examples below, but the present invention is not limited to these examples. The measurement method and evaluation method used in the present invention are as follows.

(1) MFR: The MFR of (A) propylene / ethylene random copolymer and (C) propylene homopolymer is measured in accordance with the MFR of JIS K6758 polypropylene test method (condition: 230 ° C., load: 2.16 kgf). did. (B) an ethylene / α-olefin copolymer polymerized using a metallocene catalyst; and (D)
The MFR of polyethylene was measured at 190 ° C. under a load of 2.16 kgf in accordance with JIS K6760.

(2) Impact resistance and rigidity: A sample obtained by subjecting a syringe outer cylinder having a capacity of 5 cc obtained by injection molding to γ-ray irradiation treatment was allowed to stand at 23 ° C. and 65% humidity for 200 hours. Thereafter, the syringe barrel was refrigerated at 10 ° C for 2 hours while being held in a special jig at an ambient temperature of 10 ° C, and then subjected to a method of measuring 50% breaking energy using a Charpy tester. The impact resistance was evaluated by a method in which the central part of the syringe outer cylinder was pushed in by 2 mm with a compression load tester, and the repulsive force at that time was measured. The evaluation results were expressed as relative values (%) when the comparative example was set to a reference value of 100. Larger numerical values indicate better values.

Example 1 An MFR of 15.6 g / 10 min and an ethylene content of 2.5
90 parts by weight of a propylene / ethylene random copolymer powder (manufactured by Nippon Polychem Co., Ltd.)
Ethylene / propylene / 1-hexene copolymer powder polymerized with a metallocene catalyst having a density of 6.5 g / 10 min and a density of 0.898 g / cm ³ (manufactured by Nippon Polychem)
0.10 parts by weight of a phosphorus-based antioxidant, 0.05 parts by weight of a neutralizing agent, 0.20 parts by weight of a sorbitol-based nucleating agent, and 0.05 parts by weight of an ultraviolet absorber Then, 0.03 parts by weight of a slip agent was added, and the mixture was kneaded with a supermixer under a nitrogen atmosphere. Thereafter, a peroxide compound, Perhexa 25B (manufactured by NOF CORPORATION), was converted into a polymer having a MFR of 32.0 g /
10 minutes, the mixture was mixed with a single screw extruder,
Granulation was performed at 240 ° C. to obtain a polypropylene pellet. Using the pellet, a syringe outer cylinder having a capacity of 5 cc was formed by injection molding. The syringe barrel was further irradiated with gamma rays derived from cobalt 60 so that the total irradiation amount was about 20 KGy. The syringe barrel thus obtained was evaluated for impact resistance and rigidity. Table 1 shows the results.

Example 2 The MFR was 15.3 g / 10 min and the ethylene content was 3.0.
Using 92 parts by weight of propylene / ethylene random copolymer powder (manufactured by Nippon Polychem Co., Ltd.)
The production and evaluation of the syringe barrel were performed in the same manner as in Example 1 except that the ethylene-propylene / 1-hexene copolymer powder polymerized using the metallocene catalyst was used in an amount of 8 parts by weight. Table 1 shows the results.

Example 3 A metallocene catalyst using 56 parts by weight of a propylene / ethylene random copolymer powder (manufactured by Nippon Polychem) having an MFR of 5.0 g / 10 min and an ethylene content of 4.2% by weight was used. Ethylene propylene polymerized with
1-hexene copolymer powder was 6 parts by weight,
Further, except that 38 parts by weight of a propylene homopolymer powder (manufactured by Nippon Polychem Co., Ltd.) having an MFR of 5.0 g / 10 min was additionally added, the production and evaluation of the syringe barrel were performed in the same manner as in Example 1. went. Table 1 shows the results.

Example 4 The MFR was 15.3 g / 10 min and the ethylene content was 3.0.
Using 70 parts by weight of propylene / ethylene random copolymer powder (manufactured by Nippon Polychem Co., Ltd.)
Ethylene propylene / 1-hexene copolymer powder polymerized using a metallocene catalyst was 8 parts by weight, and a propylene homopolymer powder (manufactured by Nippon Polychem Co., Ltd.) having an MFR of 5.0 g / 10 minutes 22 The production and evaluation of the syringe barrel were performed in the same manner as in Example 1 except that the weight part was additionally blended. Table 1 shows the results.

Example 5 The MFR was 15.3 g / 10 min, and the ethylene content was 3.0.
91.5 parts by weight of a propylene / ethylene random copolymer powder (manufactured by Nippon Polychem Co., Ltd.), and 8 parts by weight of an ethylene / propylene / 1-hexene copolymer powder polymerized using a metallocene catalyst. MFR of 20 g / 10 min and density of 0.95
Production and evaluation of a syringe barrel were performed in the same manner as in Example 1 except that 0.5 part by weight of polyethylene powder (manufactured by Nippon Polychem Co., Ltd.) of 8 g / cm ³ was additionally added. Table 1 shows the results.

Example 6 The MFR was 15.3 g / 10 min and the ethylene content was 3.0.
71.5 parts by weight of propylene / ethylene random copolymer powder (manufactured by Nippon Polychem Co., Ltd.) and 8 parts by weight of an ethylene / propylene / 1-hexene copolymer powder polymerized using a metallocene catalyst. 20 parts by weight of a propylene homopolymer powder (manufactured by Nippon Polychem) having an MFR of 5.0 g / 10 minutes, an MFR of 20 g / 10 minutes, and a density of 0.958 g /
polyethylene powders are cm ³ (manufactured by Japan Polychem Corporation), except that the additional blending 0.5 part by weight, Example 1
In the same manner as in the above, production and evaluation of the syringe barrel were performed.
Table 1 shows the results.

COMPARATIVE EXAMPLE 80 parts by weight of a propylene / ethylene random copolymer powder (manufactured by Nippon Polychem Co., Ltd.) having an MFR of 5.0 g / 10 minutes and an ethylene content of 4.2% by weight were used, and a metallocene catalyst was used. Example 1 except that 20 parts by weight of a propylene homopolymer powder (manufactured by Nippon Polychem Co., Ltd.) having an MFR of 5.0 g / 10 min was used instead of the ethylene / α-olefin copolymer powder polymerized using the method. In the same manner as in the above, production and evaluation of the syringe barrel were performed. Table 1 shows the results.

[0045]

[Table 1]

[0046]

Industrial Applicability The syringe barrel of the present invention is a syringe barrel excellent in rigidity while maintaining transparency and particularly excellent in impact resistance, and has great industrial value.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08J 7/00 CES C08J 7/00 CES 305 305 // (C08L 23/16 (C08L 23/16 23:08 23:08) (C08L 23/16 (C08L 23/16 23:08 23:08 23:12) 23:12) (C08L 23/16 (C08L 23/16 23:08 23:08 23:06) 23 : 06) (C08L 23/16 (C08L 23/16 23:08 23:08 23:12 23:12 23:06) 23:06) (72) Inventor Takao Kuno 1 Toho-cho, Yokkaichi, Mie Prefecture (72) Inventor Kinichi Furuichi 1st Tohocho, Yokkaichi-shi, Mie Japan Polychem Co., Ltd. (72) Inventor Shogo Okumura 1st Tohocho, Yokkaichi-shi, Mie Japan Polychem Co., Ltd. Company Material Development Center F (Reference) 4C066 AA09 BB01 CC01 DD08 EE14 GG01 PP02 4F070 AA12 AA13 AA15 AA16 AB09 AB11 AB21 AB24 AC56 AE30 BA05 BB08 4F071 AA15 AA20 AA82 AA88 AF23 AG14 AH19 BC04 4F073 AA09 BB09 BB03 BB03 BB03 BA05 BB09 BG00

Claims (6)

[Claims] (A) a melt flow rate (230 ° C.,
Propylene / ethylene random copolymer having a weight of 2.16 kg) of 0.5 to 100 g / 10 min and an ethylene content of 2.0 to 5.0% by weight: 85 to 9
9.8 parts by weight (B) The melt flow rate (190 ° C., 2.16 kg load) is 5 to 50 g / 10 min, and the density is 0.860.
Ethylene / α-olefin copolymer polymerized using a metallocene catalyst of 〜0.913 g / cm ³ :
A syringe barrel formed by molding a resin composition containing 0.2 to 15 parts by weight. (A) a melt flow rate (230 ° C.,
2.16 kg load) of 0.5 to 100 g / 10 min, and a propylene / ethylene random copolymer having an ethylene content of 2.0 to 5.0% by weight: 50 to 9
8.8 parts by weight (B) The melt flow rate (190 ° C., 2.16 kg load) is 5 to 50 g / 10 min, and the density is 0.860.
Ethylene / α-olefin copolymer polymerized using a metallocene catalyst of 〜0.913 g / cm ³ :
0.2 to 15 parts by weight (C) a propylene homopolymer having a melt flow rate (230 ° C., 2.16 kg load) of 0.5 to 100 g / 10 min: 1 to 49 parts by weight; A syringe barrel formed by molding. (A) a melt flow rate (230 ° C.,
Propylene / ethylene random copolymer having a weight of 2.16 kg) of 0.5 to 100 g / 10 min and an ethylene content of 2.0 to 5.0% by weight: 85 to 9
9.7 parts by weight (B) The melt flow rate (190 ° C., 2.16 kg load) is 5 to 50 g / 10 min, and the density is 0.860.
Ethylene / α-olefin copolymer polymerized using a metallocene catalyst of 〜0.913 g / cm ³ :
0.2 to 15 parts by weight (D) Melt flow rate (190 ° C., 2.16 kg load) is 10 to 50 g / 10 min and density is 0.94
Polyethylene that is 0 to 0.980 g / cm ³ : 0.1
A syringe barrel formed by molding a resin composition containing 1.0 to 1.0 parts by weight. 4. A melt flow rate (230 ° C.,
2.16 kg load) of 0.5 to 100 g / 10 min, and a propylene / ethylene random copolymer having an ethylene content of 2.0 to 5.0% by weight: 50 to 9
8.7 parts by weight (B) The melt flow rate (190 ° C., 2.16 kg load) is 5 to 50 g / 10 min, and the density is 0.860.
Ethylene / α-olefin copolymer polymerized using a metallocene catalyst of 〜0.913 g / cm ³ :
0.2 to 15 parts by weight (C) Propylene homopolymer having a melt flow rate (230 ° C., 2.16 kg load) of 0.5 to 100 g / 10 min: 1 to 49 parts by weight (D) Melt flow rate (190 C., 2.16 kg load) is 10 to 50 g / 10 min, and the density is 0.94.
Polyethylene that is 0 to 0.980 g / cm ³ : 0.1
A syringe barrel formed by molding a resin composition containing 1.0 to 1.0 parts by weight. 5. A syringe barrel formed by treating the resin composition according to claim 1 with a peroxide compound to reduce the molecular weight and then molding the same. 6. The syringe barrel according to claim 1, which is subjected to radiation treatment.