JPH0947486A - Laminated body and medical bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated body excellent in its transparency, heat resistance and flexibility and a medical bag for body fluids, chemicals and the like charged thereto or discharged therefrom. SOLUTION: This laminated body comprises an inner and an outer layers made of ethylene resin and an intermediate layer which is obtained by crosslinking by irradiating electronic beam a linear α-olefin copolymer to crosslink its 20%, where the copolymer had (a) a density of 0.850-0.920g/cm<3> , (b) Mw/Mn of 3 or less measured by GPC and (c) mp of 115 deg.C or lower, and is obtained by copolymerizing ethylene and a 3-20C α-olefin in the presence of a metallocene catalyst. The medical bag is composed of the laminated body.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminate obtained by using an ethylene resin for the inner and outer surface layers and using a specific ethylene copolymer as an intermediate layer by irradiating it with radiation and / or an electron beam and crosslinking it. And a medical bag used as a container for discharging or storing body fluids, drug solutions and the like.

[0002]

2. Description of the Related Art Conventionally, as a medical bag such as a soft synthetic resin bag such as a blood bag, a blood collection bag, a blood transfusion bag, etc., JP-A-5-4313 discloses a low density polyethylene inner and outer layer and an intermediate layer. A laminate comprising a copolymer of ethylene and 1-olefin having a density of 0.920 g / cm ³ or less has been proposed.
-Copolymers with olefins have a melting point which saturates at about 120 ° C even when the density decreases, and it is described that it is deviated from the conventional relationship between the density and the melting point. A distribution of the degree of branching is generated in the copolymer. Therefore, even if the degree of cross-linking is increased to 20% or more, the effect of improving the heat distortion temperature is not sufficient because of the presence of low-molecular components with many branches.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides transparency, heat resistance, and flexibility which cannot be achieved by a laminate using a conventional ethylene / α-olefin copolymer as an intermediate layer and an inner surface layer. A laminated body capable of doing, and a body fluid,
The purpose is to provide a medical bag for discharging or storing medicines.

[0004]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention have used an ethylene resin for the inner and outer surface layers, and have a linear ethylene resin having a specific molecular weight distribution and melting point in the middle layer.
When a laminate using an α-olefin copolymer is irradiated with radiation and / or an electron beam to impart heat resistance and the crosslinking rate is 20% or more, a conventional ethylene / α-olefin copolymer is obtained. To be able to produce a laminate capable of imparting transparency, heat resistance and flexibility, which cannot be achieved with the laminate used for the intermediate layer and the inner surface layer, and a medical bag for discharging or storing body fluids, drugs, etc. I found it.

That is, the present invention has a density of 0.850 to 0.9 obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms, which is produced by using a metallocene catalyst.
At 20 g / cm ³ , the molecular weight distribution determined by GPC is 3 or less, and the melting point measured by DSC is 115 ° C.
The following linear ethylene / α-olefin copolymer is used for the intermediate layer, and the one using the ethylene-based resin for the inner and outer surface layers is irradiated with radiation and / or electron beam to give a crosslinking rate of 20% or more. The laminated body and the medical bag are characterized in that

In order to obtain this laminate, it is necessary to irradiate the resin with radiation and / or an electron beam so that the crosslinking rate is 20% or more. In particular, by adopting a crosslinked structure containing no plasticizer having excellent heat resistance, it is possible to obtain a laminate and a medical product which are excellent in flexibility, transparency, heat resistance and the like, and in which plasticizer and stabilizer are not eluted at all. You can get a bag. Further, by controlling the crosslinking conditions, it is possible to impart excellent functions such as acid resistance, alkali resistance, mechanical workability, dimensional stability and rubber elasticity.

Linear ethylene / α-used in the present invention
It is considered that the olefin copolymer has a substantially uniform distribution of branching degree, uniform crosslinking occurs, and the heat resistance can be effectively improved, and the present invention will be described in detail below.

The linear ethylene / α-olefin copolymer used in the intermediate layer of the present invention is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, which is produced by using a metallocene catalyst. The density is 0.850-0.
Ratio (Mw / M) of weight average molecular weight (Mw) and number average molecular weight (Mn) determined by GPC at 920 g / cm ^3.
n) is 3 or less and one melting point measured by DSC is 1
15 ° C or less, 190 ° C according to JIS K6760,
The melt index (MFR) measured under a load of 2160 g is 0.3 to 50 g / 10 minutes. When the density exceeds this range, the required performance as a product, that is, flexibility and transparency cannot be satisfied, and when the ratio of Mw / Mn and the number of branches is outside this range, the effect of improving heat resistance becomes insufficient. Further, when the MFR is 0.3 g / 10 min or less, the load during extrusion becomes large and molding becomes difficult, and when it exceeds 50 g / 10 min, the strength of the product decreases and it is not practical.

The Mw / Mn and melting point in the present invention are specifically determined as follows.

Waters 150C ALC / GP
C (column: Tohso GMHHR-H (S), solvent:
GPC using 1,2,4-trichlorobenzene)
By the method, Mw and Mn were measured, and Mw / Mn was calculated. The column elution volume was calibrated by the universal calibration method using Tosoh standard polystyrene. The melting point (° C.) was measured using a differential scanning calorimeter “DSC-7” manufactured by Perkin Elmer. After melting the sample at 200 ° C for 5 minutes in the device, 10 ° C
It is obtained when the material is cooled to 30 ° C. at a cooling rate of / min and the temperature is raised again at a heating rate of 10 ° C./min.
The temperature at the position of the maximum peak on the endothermic curve was taken as the melting point. The melting point needs to be 115 ° C. or lower to satisfy the flexibility and transparency, and one melting point is required to improve heat resistance.

Such a linear low-density ethylene / α-olefin copolymer can be produced, for example, by using a metallocene catalyst disclosed in the following publications.

JP-A-60-35006, JP-A-6-35006
No. 0-35007, JP-A-60-35008, JP-A-3-163088, and JP-A-61-29.
6008, JP-A-63-22804, JP-A-58-19309, JP-A-60-00862, JP-A-63-61010, JP-A-63-15.
No. 2608, No. 63-264606, No. 63-280703, and No. 64-6003.
Japanese Patent Application Laid-Open No. 1-95110, Japanese Patent Application Laid-Open No. 3-62
No. 806, No. 1-259004, No. 64-45406, No. 60-106808, No. 60-137911, No. 61-
No. 296008, Japanese Patent Publication No. 63-501369, Japanese Patent Application Laid-Open No. 61-221207, Japanese Patent Application Laid-Open No. 2-22.
307, JP-A-2-173110, JP-A-2-302410, JP-A-1-129003, JP-A-1-210404, and JP-A-3-667.
No. 10, JP-A-3-70710, JP-A-1-
207248, JP-A-63-222177, JP-A-63-222178, and JP-A-63-2.
No. 22179, No. 1-14077, No. 1-301704, No. 1-319489, No. 3-74412, No. 61-26.
4010, JP-A-1-275609, JP-A-63-251405, JP-A-64-74202.
JP-A No. 2-41303, JP-A No. 1314
88, JP-A-3-56508, JP-A-3-56508
70708, JP-A-3-70709, and the like.

The method for producing a linear low-density ethylene / α-olefin copolymer which can be used in the intermediate layer of the present invention will be described below. This linear low-density ethylene / α-
The olefin copolymer is, for example, an organic transition metal compound (I) containing a cyclopentadienyl derivative, and a compound (II) and / or an organic metal compound (III) which reacts with the organic transition metal compound (I) to form an ionic complex. It can be suitably produced by copolymerizing ethylene with the above-mentioned α-olefin having 3 to 20 carbon atoms in the presence of a catalyst consisting of

As the α-olefin having 3 to 20 carbon atoms, propylene, 1-butene, 4-methyl-1-pentene, 3-methyl-1-butene, 1-pentene, 1-hexene, 1-heptene, 1 -Octene, 1-nonene, 1-
Examples thereof include decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene and 1-eicosene.

The polymerization method used can be exemplified as follows.

The polymerization conditions for the solution polymerization method are as follows. The polymerization temperature is preferably the melting point or higher in consideration of the fact that the copolymer is in a solution state and improving productivity. The upper limit of the polymerization temperature is not particularly limited,
The temperature is preferably 300 ° C. or lower in order to suppress the chain reaction that causes a decrease in the molecular weight and not reduce the catalyst efficiency. Also,
The pressure during polymerization is not particularly limited, but is preferably atmospheric pressure or higher in order to improve productivity.

The conditions for the high pressure polymerization method are as follows. The polymerization temperature is preferably 120 ° C. or higher in consideration of the fact that the copolymer is in a solution state and improving productivity. Although the upper limit of the polymerization temperature is not particularly limited, it is preferably 300 ° C. or lower in order to suppress the chain transfer reaction that causes a decrease in the molecular weight and not decrease the catalyst efficiency. The pressure during the polymerization is not particularly limited, but stable polymerization conditions can be obtained in the high pressure process.
It is preferably at least 00 kgf / cm ² .

In the gas phase polymerization method, the high temperature is not preferable because the copolymer is in a powder state, and the temperature is preferably 100 ° C. or lower. The lower limit of the polymerization temperature is not particularly limited, but is preferably 50 ° C. or higher in order to increase productivity.

The linear low-density ethylene / α-olefin copolymer used in the intermediate layer in the present invention may be used alone, but 1 to 40 high-pressure low-density polyethylene may be used.
It can also be used as a composition containing wt%. Compositions with high pressure low density polyethylene have improved transparency and moldability. If necessary, additives such as antioxidants, weather resistance stabilizers, antistatic agents, lubricants, antiblocking agents and the like usually used for polyolefins may be added.

The ethylene resin for the inner and outer surface layers used in the present invention means low density polyethylene produced by a high pressure method, an ethylene vinyl acetate copolymer having a vinyl acetate content of 7% or less, or a conventional Ziegler. It is a linear low density polyethylene produced using a catalyst or a metallocene catalyst. The linear low density polyethylene used has a density of 0.9.
It is preferably 20 g / cm ³ or more because it can prevent the adsorption of the drug. The low density polyethylene used preferably has a melting point of 110 ° C. or higher.

The laminate thus obtained can be obtained by extrusion molding, calender molding, blow molding or the like to form a sheet or a cylinder. these,
It is manufactured into a predetermined shape and size by heat sealing, an injection port and the like are attached, and thereafter, radiation and / or electron beams, which is a feature of the present invention, are cross-linked to perform the intended laminate and medical use. Make a bag.

The crosslink density of this medical bag can be controlled by the irradiation dose, and generally heat resistance is imparted as the crosslink density progresses.

It has been found that the crosslinking rate of about 20% or more meets the purpose of the invention, and the irradiation dose is 1 to 15 Mrad, preferably 2 to 10 Mrad in the case of radiation.
It is Mrad.

In this case, as an example of heat resistance,
Ethylene / 1-butene copolymer, 60-7 without irradiation
It was 0 ° C, but it was 1 when the cross-linking rate was 75% by irradiation.
It was confirmed that high-pressure steam sterilization at 25 ° C for 30 minutes was possible.

As described above, in the present invention, it is possible to find a feature that a material which can withstand autoclave sterilization, which is an essential condition for a medical instrument, and has excellent flexibility is obtained. It is possible to provide a hygienic medical device in combination with the original characteristic of not containing a plasticizer.

As the irradiation source, cobalt 60 can be used as a radiation source, and a resonant transformation electron beam source can be used as an electron beam source, and the latter can be processed in a short time as an irradiation source.

The laminate thus obtained is used, for example, in a blood bag for blood storage and blood collection, an infusion set, a transfusion set, and the like. Generally, these medical devices are merely examples, and the medical devices are not limited thereto as long as they meet the object of the present invention.

[0028]

EXAMPLES The present invention will be described below with reference to examples, but is not limited to these examples.

Reference Example Production of Linear Ethylene / α-Olefin Copolymer The linear ethylene / α-olefin copolymer used in the intermediate layer was polymerized using a reactor equipped in a high temperature / high pressure method. It was 1- as a comonomer for ethylene and density adjustment
Butene or 1-hexene was continuously pressed into the reactor to keep the total pressure at 950 Kg / cm ² . 1 reactor
Stir at 500 rpm and add the following catalyst solution to 120 cm ³
/ Rate the reactor at a rate of 193 hours
The temperature was set to be 0 ° C, and the polymerization was continuously carried out.

A toluene solution of diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride as a transition metal compound (I) containing a cyclopentadienyl derivative and a toluene solution of triisobutylaluminum as an organometallic compound (III) are used. , Aluminum was added in an amount of 250 times mol per zirconium. Further, as a compound (II) which reacts with the catalyst component to form a complex, a toluene solution of N, N-dimethylanilnium tetrakis (pentafluorophenyl) borate is added so that the amount of boron is twice the mole of zirconium. To obtain a catalyst solution. In the examples and comparative examples, the density was measured by a density gradient tube kept at 23 ° C., according to JIS K6760, after a test piece was immersed in hot water at 100 ° C. for 1 hour and then slowly cooled to room temperature. The cross-linking rate was calculated by putting the sample in a stainless steel mesh, refluxing it with boiling xylene for 12 hours for extraction, and extracting the extraction residue after drying under reduced pressure as a weight percentage.

Crosslinking is performed by E manufactured by Nisshin High Voltage Co., Ltd.
Irradiation was carried out in air at room temperature using PS-750.

The flexibility was evaluated by a tensile tester with a sample width of 10 mm, an initial sample length of 50 mm, and a pulling speed of 50 mm /
Tensile strength was measured in minutes, and tensile strength at an elongation of 5% was measured.

The haze was measured according to ASTM D-1003.

To evaluate the appearance of the sample, a bag was filled with pure water, steam sterilized at 125 ° C. for 30 minutes, and deformation and wrinkle formation were observed.

These evaluations are shown in the following 4 ranks.

⊚: Very good, ◯: Good, Δ: Slightly bad, ×: Poor Example 1 Produced by the high pressure method on the inner and outer surface layers, the density was 0.924 g.
/ Cm ³ , melting point of 111 ° C, MFR of 2 g / 10 min, low-density polyethylene was used, and the intermediate layer was polymerized using a metallocene catalyst. Density was 0.900 g / cm ³ and melting point was 92 ° C, MFR. Is 1.0 g / 10 min, and molecular weight distribution by GPC is Mw / Mn = 1.8.
Using the butene copolymer, a laminate having an inner and outer surface layer thickness of 25 μ and an intermediate layer thickness of 200 μ was molded under the following conditions.

Extruder: Placo 3-kind 3-layer water-cooled inflation molding machine Molding conditions: cylinder temperature 1; 190 ° C. 2; 190 ° C. 3; 190 ° C. head; 200 ° C. die; 200 ° C. Example 2 Example 1 for intermediate layer The linear ethylene / 1-butene copolymer used in Example 1 was replaced with 90% by weight of the linear ethylene / 1-butene copolymer used in Example 1 and MFR of 0.3.
Density 0.920 g / cm ³ at g / 10 minutes, melting point 11
The same conditions as in Example 1 were used, except that a composition of high-pressure low-density polyethylene at 0 ° C. and 10% by weight was used.

Example 3 The inner and outer surface layers were polymerized using a Ziegler catalyst instead of the high-pressure low-density polyethylene used in Example 1, and had a density of 0.935 g / cm ³ , a melting point of 126 ° C. and an MFR of The same conditions as in Example 1 were used except that a linear ethylene / 1-hexene copolymer of 2.0 g / 10 min was used.

Example 4 The inner and outer surface layers were polymerized using a metallocene catalyst in place of the high-pressure low-density polyethylene used in Example 1, and had a density of 0.930 g / cm ³ , a melting point of 121 ° C. and an MFR of The same conditions as in Example 1 were used except that a linear ethylene / 1-hexene copolymer of 2.0 g / 10 min was used.

Comparative Example 1 The inner and outer surface layers were manufactured by a high pressure method and had a density of 0.924 g.
/ Cm ³ , MFR of 2 g / 10 min using low density polyethylene, was polymerized using a Ziegler catalyst in the intermediate layer, density 0.900 g / cm ³ , melting point 121 ℃ 1,
1.0g of MFR having 3 of 10 degreeC and 82 degreeC
/ 10 min, molecular weight distribution by GPC Mw / Mn = 4.2
Using a linear ethylene 1-butene copolymer which is
A laminate having an inner and outer surface layer thickness of 25 μ and an intermediate layer thickness of 200 μ was molded under the same conditions as in Example 1. Comparative Example 2 The inner and outer surface layers were manufactured by a high pressure method and had a density of 0.924 g.
/ Cm ³ , MFR of 2 g / 10 min, low density polyethylene was used, and the density was 0.930 g / cm ³ , MFR was 1.0 g /, which was polymerized using a metallocene catalyst in the intermediate layer.
Using a linear ethylene / 1-butene copolymer having a molecular weight distribution Mw / Mn = 1.8 by GPC for 10 minutes, under the same conditions as in Example 1, the inner / outer surface layer thickness was 25 μm, and the intermediate layer thickness was 200 μm. The laminate was molded.

Comparative Example 3 Under the same conditions as in Example 1, low density polyethylene having a density of 0.924 g / cm ³ and an MFR of 2 g / 10 min was used for the inner and outer surface layers and the intermediate layer. Thickness 25
A 0 μ monolayer was molded.

Comparative Example 4 The inner and outer surface layers were manufactured by a high pressure method and had a density of 0.924 g.
/ Cm ³ , MFR of 2 g / 10 min using low density polyethylene, was polymerized using Ziegler catalyst in the intermediate layer, density 0.900 g / cm ³ , MFR 1.0 g /
For 10 minutes, a linear ethylene / 1-butene copolymer having a molecular weight distribution Mw / Mn = 3.5 by GPC was used, and under the same conditions as in Example 1, the inner and outer surface layer thicknesses were 25 μm and the intermediate layer thickness was 200 μm. The laminate was molded.

The degree of crosslinking and the evaluation results of the above Examples and Comparative Examples are summarized in Table 1.

[0044]

[Table 1]

[0045]

The ethylene-based resin is used for the inner and outer surface layers obtained by the present invention, and ethylene and C 3 are used for the intermediate layer.
Of a specific linear ethylene / α-olefin copolymer obtained by copolymerizing 20 to 20 α-olefins, a laminate obtained by cross-linking with a radiation and / or an electron beam, and body fluids, chemicals, etc. The medical bag for discharge or storage was superior in heat resistance to the medical bag produced by the conventional method and was satisfactory in flexibility and transparency.

Claims (2)

[Claims] 1. A density obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms, which is produced by using an ethylene resin for the inner and outer surface layers and using a metallocene catalyst for the intermediate layer. Is 0.850 to 0.920 g / cm ³ ,
(B) The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by GPC (gel permeation chromatography) is 3 or less, and (c) D
A laminate obtained by crosslinking a laminate comprising a linear ethylene / α-olefin copolymer having a melting point of 115 ° C. or less as measured by SC to 20% or more by radiation and / or electron beam irradiation. . 2. A medical bag comprising the laminate according to claim 1.