JP2000070340A - Medical bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medical bag for medicinal liquid, blood, or the like excellent in hygiene, flexibility, transparency, heat resistance and further in pinhole resistance to be a problem during transportation. SOLUTION: This medical bag is mainly composed of a copolymer of a 3-18C α-olefin and an ethylene compound having an MFR value of 0.1-20 g/10 min., the maximum peak temperature in a temperature rise elutriation fractionation(TREF) elution curve of 65-92 deg.C and an H/W value of 2 or more (H: peak height and W: width at 1/3 height of H).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to hygiene, flexibility,
The present invention relates to a medical bag that is excellent in transparency, heat resistance, pinhole resistance, etc., and that holds a chemical solution, blood, and the like.

[0002]

2. Description of the Related Art At present, a hard container made of glass, polyethylene, polypropylene or the like and a soft bag made of polyvinyl chloride containing a plasticizer are known as medical containers. However, in the former case, when the content liquid is dropped, air must be introduced using a ventilation needle or an infusion set having a ventilation hole. In addition, contamination of the content liquid occurs. Further, a container made of polyethylene or polypropylene has a problem that transparency is insufficient and the amount of the content liquid is difficult to see. On the other hand, the latter does not require the introduction of the air, and has safety such as the bag itself being squeezed by the atmospheric pressure as the content liquid is dripped and convenience in transportation. But,
There is a problem with the toxicity of plasticizers and residual monomers contained in polyvinyl chloride. In addition, due to recent environmental problems, polyvinyl chloride has been avoided and there is a movement to completely eliminate it. Therefore, an alternative material is desired. On the other hand, in terms of flexibility, transparency, hygiene and the like, ethylene-vinyl acetate copolymer,
A medical bag using a polymer such as an elastomer for the intermediate layer has been proposed (JP-A-58-165866).
However, these polymers used for the intermediate layer have poor heat resistance, and thus have a problem in that appearance is poor, such as wrinkling of the bag during sterilization and deterioration in transparency after sterilization. Further, a problem such as generation of a pinhole during transportation may occur.

[0003]

The present invention does not have the above-mentioned problems, that is, it has not only good hygiene, but also excellent flexibility and transparency, heat resistance, and problems during transportation. Another object of the present invention is to provide a medical bag for containing a medicinal solution, blood, and the like that has excellent pinhole resistance.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of such a situation, and as a result, have found that ethylene / α- having an elution curve obtained by specific MFR and elevated temperature elution fractionation (TREF). The inventors have found that the use of an olefin copolymer can achieve the object of the present invention, and have completed the present invention.

That is, the present invention provides a method for producing
A medical bag mainly comprising a copolymer with α-olefins of Nos. 1 to 18 and having the following physical properties (a) and (b). (A) MFR = 0.1-20 g / 10 min. (B) Temperature rise elution fractionation (TREF) The maximum peak temperature of the elution curve is 65-92 ° C., and the height of the peak is H
And the width at one third of the height is W,
H / W value is 2 or more.

Further, the present invention relates to the present invention, wherein said ethylene and carbon number 3
The medical bag according to any one of the preceding claims, wherein a copolymer of α-olefins of Nos. To 18 is polymerized using a metallocene compound containing a tetravalent transition metal as a polymerization catalyst.

[0007]

Embodiments of the present invention will be described below. I. Ethylene / α-olefin copolymer The medical bag of the present invention comprises ethylene and α-olefin having 3 to 18 carbon atoms.
Mainly a copolymer with olefin (hereinafter, referred to as “ethylene / α-olefin copolymer”), the following physical properties (a)
And (b).

[0008] 1. Physical properties (a): Melt flow rate The medical bag of the present invention has a melt flow rate (melt flow rate: hereinafter abbreviated as “MFR”) of 0.1 to 20 g / 10.
Min, preferably 0.1 to 15 g / 10 min, more preferably 0.1 to 10 g / 10 min. The MFR mentioned here is JIS-K7210 (190 ° C., 2.
16 kg load). The MFR
Exceeds the above range, heat resistance, film strength is reduced,
This is not preferable because film formation of the film becomes unstable. On the other hand, if the MRF is less than the above range, the resin pressure increases, and the extrudability decreases, which is not preferable.

[0009] 2. Physical property (b): maximum peak of elution curve by temperature-rise elution fractionation The temperature of the maximum peak of the elution curve obtained by the temperature-rise elution fractionation of the medical bag of the present invention is 65 to 92 ° C, preferably 68 to 90 ° C. And the height of the peak is H
When the width of the peak at one third of the height is W, the value of H / W is 2 or more, preferably 2.5 or more.

Here, the temperature rise elution fractionation (TREF: T
emperatur RisingElution F
The term "fraction" means that once the polymer is completely dissolved, it is cooled, a thin polymer layer is formed on the surface of the inert carrier, and then the temperature is raised continuously or stepwise to recover the eluted component (polymer). In this method, the concentration is continuously detected to determine the amount of the eluted component and the elution temperature.

A graph drawn by the elution fraction and the elution temperature is an elution curve, from which the composition distribution (molecular weight and crystallinity distribution) of the polymer can be measured. For details of the method and apparatus for measuring the temperature rise elution fractionation (TREF), see Journal of Appl.
ied Polymer Science, Vol. 26,
4217-4231 (1981).

The shape of the elution curve obtained by TREF depends on the molecular weight and crystallinity distribution of the polymer.
For example, there are one peak, two peaks, and three peaks, and the two-peak curve has a higher elution fraction than a peak with a lower elution temperature. Is large (peak height is high)
And peaks with higher elution temperatures have lower elution fractions (lower peak heights) than peaks with lower elution temperatures
There are cases.

FIG. 1 shows an elution curve in the case of one peak, FIG. 2 shows an elution curve in the case of two peaks, and FIG. FIG. 2 (a) shows the case where the peak of the higher elution temperature has a higher peak height than the peak of the lower elution temperature, and FIG. 2 (b) shows the case of FIG. Represents a case where a peak having a higher elution temperature has a lower peak height than a peak having a lower elution temperature.

In the present invention, the maximum peak of the elution curve refers to the peak in the elution curve having one peak and the maximum peak in the elution curve having two or more peaks.
The peak at which the elution fraction is the maximum (in FIGS. 2 and 3,
(Peak indicated by p). Further, the H / W in the present invention is obtained by calculating the height of the maximum peak as H and the width at one third of the height as W as shown in FIGS. As shown in FIG. 1, when there is one peak, the peak is obtained from the height and width of the peak. In the elution curve having two or more peaks, a valley between the maximum peak and another peak is formed. Depending on the shape, the width at the height of one-third of the height of the maximum peak may be the width of the curve formed from the maximum peak. It may be. In this case, the width of the entire curve formed from the maximum peak and the other peaks is W (see FIGS. 2A and 3). Even if there are two or more peaks, if there is another peak whose valley between the maximum peak is less than one third of the height of the maximum peak, such a peak will have a width of It does not participate in the calculation of W (see FIG. 2B).

The TRE of the present invention thus determined
When the temperature and H / W of the maximum peak of the elution curve due to F are within the above ranges, a polyolefin resin having a narrow composition distribution and uniform crystallinity can be obtained, and there is no sticky component and no elution component to the content liquid. Film strength and pinhole resistance are improved. On the other hand, if the temperature of the maximum peak by TREF exceeds the above range, the resin contains many high crystalline components,
It is not preferable because the film strength, pinhole resistance and flexibility are reduced. On the other hand, if the peak temperature is lower than the above range, heat resistance is undesirably deteriorated. Also, H /
If the value of W is less than the above range, the crystallinity distribution of the resin is too wide, and the film strength and the pinhole resistance are undesirably reduced.

The ethylene / α-olefin copolymer having the above-mentioned properties has a constitutional unit derived from ethylene as a main component, and the α-olefin used as a comonomer has 1 to 3 carbon atoms. -Olefins, specifically, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene,
-Methyl-pentene-1,4-methyl-hexene-1,
4,4-dimethylpentene-1 and the like can be mentioned. As the comonomer, the above-mentioned α-olefin is not limited to one kind, and a multi-component copolymer using two or more kinds such as a terpolymer is also preferably included. The proportion of ethylene units in the copolymer is preferably at least 80 mol% and the comonomer is less than 20 mol%. For example, as a known method for controlling the distribution of molecular weight and crystallinity,
A polymer having desired physical properties can be obtained by appropriately employing a method of adjusting the polymerization temperature or the comonomer amount.

The method for producing the ethylene / α-olefin copolymer is not particularly limited as long as a product satisfying the above physical properties can be produced.

For example, the catalyst may be based on a Ziegler type catalyst (ie, based on a combination of a supported or unsupported halogen-containing titanium compound and an organoaluminum compound), a Phillips type catalyst (ie, based on supported chromium oxide (Cr ⁶⁺ )). ), A Kaminsky type catalyst (ie, based on a combination of a supported or unsupported metallocene compound and an organoaluminum compound, especially an alumoxane).

As the polymerization method, a slurry method in the presence of these catalysts, a gas phase fluidized bed method (for example,
No. 3011), a solution method, or a high-pressure bulk polymerization method at a pressure of 200 kg / cm ² or more and a polymerization temperature of 100 ° C. or more.

Since the ethylene / α-olefin copolymer in the present invention preferably has a relatively narrow composition distribution, it is particularly preferable to use a Kaminski type catalyst.

Ethylene α using Kaminski type catalyst
-Specific methods for producing olefin copolymers include JP-A-58-19309, JP-A-59-95292,
JP-A-60-35005, JP-A-60-35006
JP-A-60-35007, JP-A-60-3500
No. 8, JP-A-60-35009, JP-A-61-130
No. 314, JP-A-3-1630088, European Patent Application Publication No. 420,436, U.S. Pat. No. 5,055,438, and International Publication W.
O91 / 04257, etc.,
Metallocene butterflies, metallocene / alumoxane catalysts, or, for example, WO 92/07123.
And the like, a metallocene compound and a metallocene catalyst are used to form a stable ion to form a stable ion. A method of copolymerizing an olefin can be used.

The ethylene / α-olefin copolymer in the present invention is preferably an ethylene / α-olefin copolymer polymerized using a metallocene compound containing a tetravalent transition metal as a polymerization catalyst. Specifically, mono-, di- and tri-cyclopentadienyl or substituted cyclopentadienyl metal compounds can be used.

The medical bag of the present invention may be composed of only the ethylene / α-olefin copolymer which is the above-mentioned main component, but in addition to the above-mentioned range, the effect of the present invention is not significantly impaired. Auxiliary additives generally used as a resin composition can be blended as required.

Examples of such auxiliary additives include antioxidants (of which phenol and phosphorus antioxidants are preferable), antiblocking agents, neutralizing agents, and heat stabilizers.

Further, in order to improve bubble stability during molding to the extent that the effects of the present invention are not impaired with respect to the total weight of the ethylene / α-olefin copolymer, a high-pressure low-density polyethylene (HP -LDPE) in an amount of 3 to 40% by weight, and / or high-density polyethylene (HDPE) in an amount of 3 to 40% by weight in order to improve heat resistance. In order to impart flexibility, various rubbers and elastomers can be blended in an amount of 3 to 75% by weight.

II. Form of Medical Bag The ethylene-α-olefin copolymer according to the present invention can be used as a medical bag by forming it into a film or sheet and heat-sealing it. In JIS, a sheet having a thickness of 250 μ or more is defined as a sheet. Medical bags are generally composed of a multi-layer film or a multi-layer sheet of a layer having heat resistance and a layer having flexibility, but the medical bag of the present invention is transparent even when used as a single film. It is characterized in that it sufficiently satisfies physical properties such as properties, flexibility, heat resistance and pinhole resistance and can be suitably used as a medical bag.

III. Formation of Single Film or Sheet In the production of a single film in the present invention, air-cooled inflation molding, air-cooled two-stage cooling inflation molding, T-die film molding, T-die sheet molding, water-cooled inflation molding, extrusion blow molding and the like can be adopted. it can.

[0028]

The following examples and comparative examples are provided to further illustrate the present invention. Measurement of physical properties and evaluation of sheet physical properties in these Examples and Comparative Examples were carried out by the following methods.

1. Method for measuring physical properties (1) Measured according to MFR Jls-K7210 (190 ° C, 2.16 kg load).

(2) Measurement of elution curve obtained by temperature-rise elution fractionation (TREF) The peak of the elution curve by temperature-rise elution fractionation (TREF) in the present invention is obtained by dissolving the polymer once at a high temperature and then completely dissolving the polymer. Cooling to form a thin polymer layer on the surface of the inert carrier, then increasing the temperature continuously or stepwise to recover the eluted components (polymer) and continuously detecting the temperature, This was carried out by a method for determining the amount of the eluted component (elution amount) and the elution temperature. The peak of the elution curve of the present invention is determined from the graph (elution curve) drawn thereby, and the composition distribution of the polymer is measured.

The measurement of the elution curve was specifically performed as follows. The measurement was performed using a cloth separation device (CFC T150A manufactured by Mitsubishi Chemical Corporation) as a measurement device according to the measurement method in the attached operation manual. This cross-separation apparatus uses a temperature-rise elution separation (TREF) mechanism for separating a sample by using a difference in dissolution temperature, and a size exclusion chromatograph (Size Exclusion Chromatog) for further separating the separated fraction according to molecular size.
(SECRY) is connected online.

First, the sample to be measured (ethylene · α
-Olefin copolymer) using a solvent (o-dichlorobenzene) to give a concentration of 4 mg / ml.
It was melted at ℃ and injected into a sample loop in the measuring device. The following measurements were performed automatically according to the set conditions.

The sample solution held in the sample loop is separated by using a difference in dissolution temperature in a TREF column (inside diameter of 4 m filled with glass beads as an inert carrier).
m, 150 mm length stainless steel column attached to the device)
Was injected 0.4 ml. The sample was cooled at a rate of 1 ° C./min from 140 ° C. to 0 ° C. and coated on the inert carrier. At this time, from the high crystal component (the one that is easy to crystallize) to the low crystal component (the one that hardly crystallizes)
The polymer layer is formed on the surface of the inert carrier in this order.

After holding the TREF column at 0 ° C. for an additional 30 minutes, 2 ml of the dissolved component at a temperature of 0 ° C. was added to 1 ml.
The mixture was injected from the TREF column into a SEC column (AD80M · S, Showa Denko KK, 3 tubes) at a flow rate of ml / min. SE
While fractionation by molecular size is performed in C, TREF
The column was heated to the next elution temperature (5 ° C.) and held at that temperature for about 30 minutes. The measurement of each elution section by SEC was performed at intervals of 39 minutes. The following temperature was used as the elution temperature, and the temperature was raised stepwise.

Elution temperature (° C.): 0.5, 10, 15, 2
0, 25, 30, 35, 40, 45, 49, 52, 5
5, 58, 61, 64, 67, 70, 73, 76, 7
9, 82, 85, 88, 91, 94, 97, 100, 1
02, 120, 140 ° C

With respect to the solution separated according to the molecular size in the SEC column, the absorbance in proportion to the polymer concentration was measured with an infrared spectrophotometer attached to the apparatus (wavelength 3.42 μm).
m, detection by stretching vibration of methylene) to obtain chromatograms for each elution temperature category. Using built-in data processing software,
The base line of the chromatogram of each elution temperature section obtained by the above measurement was drawn and subjected to arithmetic processing. The area of each chromatogram was integrated and an integrated elution curve was calculated. Also,
This integrated elution curve was differentiated by temperature to calculate a differential elution curve. The plot of the calculation results was output to a printer. In the plot of the output differential elution curve, the elution temperature is plotted on the horizontal axis.
The difference was 89.3 mm per 0 ° C. and the differential amount on the vertical axis (elution fraction: the total integrated elution amount was standardized to 1.0, and the change at 1 ° C. was defined as the differential amount) at 76.5 mm per 0.1. .

Next, the temperature at the highest peak (maximum peak) from the differential elution curve is defined as the maximum peak temperature, and the peak height of the maximum peak is defined as H, and the height is one third of that. The value of H / W was calculated with the width at W as W.

2. Method for evaluating physical properties of sheet (1) Haze (HAZE) Measured according to Jls-K7105. The smaller the value, the more transparent and excellent.

(2) Vertical Tensile Elastic Modulus (Flexibility) In accordance with ISO-R1184, the obtained sample sheet was measured for longitudinal elastic modulus in the vertical direction by an Instron type autograph. The smaller the value, the more flexible and excellent.

(3) Puncture Strength The obtained sample sheet was used as a test piece and was attached to an autograph DCS2000 manufactured by Shimadzu Corporation with a conical jig (tip angle: 0.25R, base diameter: 15.6 mm, height; 18.
5 mm), and a conical jig was pierced into the sheet at a speed of 50 mm / min under an atmosphere of 23 ° C. The maximum strength when the sheet was torn (a hole was made) was defined as the piercing strength.

(4) Heat resistance at 110 ° C. A cylindrical sample sheet (two stacked sheets) is cut out into a size of 140 mm × 140 mm.
It was heat-sealed on three sides to form a bag. Air was injected into the inside, the inner surfaces were not in contact with each other, and the other side was heat-sealed. The sample was placed in a high-temperature and high-pressure cooking sterilization tester (model RCS-40RTGN, Hisaka Seisakusho Co., Ltd.), and then pressurized, the ambient temperature was raised to 110 ° C., and kept at 110 ° C. for 20 minutes. Then, a bag-shaped sample containing air was taken out and evaluated according to the following criteria. A sample with a rating of ○ has heat resistance and is excellent. X: When a wrinkle state occurs in the sample bag or when the transparency is deteriorated. ：: When no wrinkles occurred in the sample bag and there was no change in appearance before the temperature was applied.

Further, the ethylene and ethylene used in Examples and Comparative Examples were used.
The α-olefin copolymer and the film were synthesized and formed as follows. 1. Preparation of Ethylene / α-Olefin Copolymer The catalyst was prepared by the method described in JP-A-61-130314. That is, to 2.0 mmol of the complex ethylenebis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, methylammonoxane (manufactured by Toyo Stouffer Co., Ltd.) was added 1000 times as much as the above complex, and diluted to 10 liters with toluene. Thus, a catalyst solution was prepared, and polymerization was performed by the following method. A mixture of ethylene and 1-hexene was added to a stirred autoclave-type continuous reactor having an inner volume of 1.5 liters and the composition of 1-hexene was 7
5% by weight, and the pressure in the reactor was 130
The reaction was maintained at 0 kg / cm ² and at a temperature of 167 ° C.
After completion of the reaction, an ethylene / 1-hexene copolymer “PE-1” having an MFR of 2.2 g / 10 min, a peak temperature of an elution curve by TREF of 75 ° C., and an H / W of 4.8 was obtained. Also, a catalyst was prepared and polymerized in the same manner as described above except that the composition of 1-hexene and the polymerization temperature during polymerization were changed. The MFR was 2.2 g / 10 min, and the peak temperature of the elution curve by TREF was 80%. An ethylene / 1-hexene copolymer “PE-2” having an H / W of 13.3 ° C. was obtained. Further, except that the composition of 1-hexene and the polymerization temperature at the time of polymerization were changed, catalyst preparation and polymerization were carried out in the same manner as described above, and MF was obtained.
R-1 is 2.2 g / 10 min, the peak temperature of the elution curve by TREF is 63 ° C., and H / W is 3.9.
A hexene copolymer “PE-3” was obtained.

2. Film Forming and Evaluation Using the copolymer composition prepared by the above method, water-cooled single-layer inflation molding was performed under the following conditions, and the single-layer sheet was evaluated. <Molding conditions> Model: Placo water-cooled inflation molding machine Screw diameter: 50 mm φ L / D; 28 temperature; 180 ° C. Die diameter; 100 mm φ die lip; 3 mm Die temperature; 190 ° C. Blow ratio; 1.4 Sheet thickness;

Example 1 "PE-1" (MFR: 2.2 g /
10 minutes, peak temperature of elution curve by TREF; 75
C., H / W: 4.8), and water-cooled inflation molding was performed under the above conditions to obtain a sheet having a thickness of 300 μm and evaluated. The results are as shown in Table 1.

Example 2 "PE-2" obtained by the above method (MFR: 2.2 g /
10 minutes, peak temperature of elution curve by TREF; 80
C., H / W; 13.3), and water-cooled inflation molding was performed under the above conditions to obtain a sheet having a thickness of 300 μm.
An evaluation was performed. The results are as shown in Table 1.

[0046]

[Table 1]

Comparative Example 1 "Novatech LL UF230" manufactured by Nippon Polychem Co., Ltd.
(MFR: 1.1 g / 10 min, peak temperature of elution curve by TREF; 90 ° C., H / W: 0.85), water-cooled inflation molding was performed under the above conditions, and the thickness was 30
A sheet of 0 μm was obtained and evaluated. The results of the evaluation are as shown in Table 2. Although heat resistance is good, flexibility, piercing strength is inferior, and transparency is slightly inferior.

Comparative Example 2 "Novatech HDHJ560" manufactured by Nippon Polychem Co., Ltd.
(MFR: 7 g / 10 min, peak temperature of elution curve by TREF: 98 ° C., H / W: 8.5), water-cooled inflation molding was performed under the above conditions to obtain a sheet having a thickness of 300 μm, and evaluation was performed. went. The results of the evaluation are as shown in Table 2. Although heat resistance is good, flexibility, piercing strength and transparency are considerably inferior.

Comparative Example 3 "Ultzex 1020L" manufactured by Mitsui Chemicals, Inc. (M
FR: 2 g / 10 min, peak temperature of elution curve by TREF; 66 ° C., H / W: 0.75), water-cooled inflation molding was performed under the above conditions to obtain a sheet having a thickness of 300 μm and evaluated. Was. The results of the evaluation are as shown in Table 2. Although the heat resistance is good, the transparency is satisfactory, but the piercing strength is poor and the flexibility is slightly poor.

Comparative Example 4 "PE-3"(MFR; 2.2 g /
10 minutes, peak temperature of elution curve by TREF; 63
C., H / W: 3.9), and water-cooled inflation molding was performed under the above conditions to obtain a sheet having a thickness of 300 .mu.m and evaluated. The results of the evaluation are as shown in Table 2. Although transparency, flexibility, and piercing strength are good, heat resistance is inferior, which is not preferable.

[0051]

[Table 2]

[0052]

Industrial Applicability The medical bag of the present invention not only has good hygiene, but also has remarkably excellent flexibility and transparency, heat resistance, and pinhole resistance (a puncture strength) which is a problem during transportation. ) Can also be suitably used in the medical field such as infusion bags.

[Brief description of the drawings]

FIG. 1 is a diagram showing an elution curve of TREF when there is one peak.

FIG. 2 is a diagram showing an elution curve of TREF when there are two peaks.

FIG. 3 is a diagram showing an elution curve of TREF when there are three peaks.

[Explanation of symbols]

 p Maximum peak of elution curve H Maximum peak height W Width at 1/3 of maximum peak height

Claims (2)

[Claims] 1. A medical bag mainly comprising a copolymer of ethylene and an α-olefin having 3 to 18 carbon atoms and having the following physical properties (a) and (b). (A) MFR = 0.1-20 g / 10 min. (B) Temperature rise elution fractionation (TREF) The maximum peak temperature of the elution curve is 65-92 ° C., and the height of the peak is H
And the width at one third of the height is W,
H / W value is 2 or more. 2. The copolymer of ethylene and an α-olefin having 3 to 18 carbon atoms, which has been polymerized using a metallocene compound containing a tetravalent transition metal as a polymerization catalyst. Medical bag.