JPH04292170A - Base material for medical use container - Google Patents

Abstract

PURPOSE:To obtain the base material for medical use container having the excellent balance of transparency, resilience and heat resistance. CONSTITUTION:The base material for medical use containers is a laminate consisting of polybutene-1 (A) and low-density polyethylene polymer and/or ethylene/vinyl acetate polymer (B), the innermost layer and/or outermost layer is formed of (A). Then, the base material for medical use containers exhibiting the performance satisfactory in resilience, transparency, heat resistance, and hygiene is obtd.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base material for medical containers. Specifically, the present invention provides a flexible container (
The present invention relates to base materials for medical containers suitable for soft tubes (connecting pipes) for transportation, etc.

0002

[Prior Art] Polymer materials used to form containers and tubes used in medical procedures such as blood collection, blood transfusion, and infusions are not only safe and hygienic, but also have flexibility, transparency, and heat resistance, and are especially suitable for high-pressure steam sterilization. It is well known that properties that can withstand high temperatures are required. By the way, polyvinyl chloride, low-density polyethylene, and ethylene-vinyl acetate copolymers have conventionally been mainly used for the above-mentioned purposes, but soft polyvinyl chloride inevitably suffers from the problem of plasticizer elution and discoloration due to light or heat. In the case of low-density polyethylene, it generally lacks a balance between flexibility and heat resistance. Due to the blocking phenomena and deformations that occur, high-density polyethylene is susceptible to limitations in its application in autoclaving, while high-density polyethylene has considerable heat resistance but has problems with flexibility and transparency. Furthermore, the ethylene-vinyl acetate copolymer usually has a vinyl acetate content of about 10 to 18% by weight, but it has the same drawbacks as low-density polyethylene. Crosslinking treatment using radiation or the like is effective in improving the heat resistance of low-density polyethylene and ethylene-vinyl acetate copolymers, but adding this operation creates a new problem in that the process becomes unavoidably complicated.

In order to solve these problems, various improvements have been attempted, particularly the idea of combining polymers with complementary properties to form a multilayer body, that is, making the inner and outer layers relatively heat resistant. A number of proposals have been proposed to achieve a balance between heat resistance and flexibility by forming the film using a certain polymer and using a flexible polymer for the intermediate layer or the like. For example, JP-A-56-101850,
JP-A-58-165866, JP-A-59-97670
No., JP-A-62-44256 and JP-A-63-24
No. 8633, both of which use "relatively high-density" low-density polyethylene for the innermost layer and outermost layer, and "relatively low-density" or flexible polyethylene-based polymer for the intermediate layer. However, as mentioned above, low-density polyethylene lacks heat resistance, and it has been pointed out that it is substantially difficult to raise the temperature to 110° C. or higher for high-pressure steam sterilization.

[0004] On the other hand, in order to maintain the outer surface of a plastic container (inner packaging material) containing an infusion solution or other medicinal solution in a sterile state and to prevent the deterioration of the medicinal solution due to oxygen, the container is further treated. It is common practice to wrap and seal the product in other packaging materials, especially plastic films or sheets (outer packaging material). In conventional methods, a polymer such as polyethylene or an ethylene-vinyl acetate copolymer is used as the material for the inner package, and the inner package is subjected to high-pressure steam sterilization while being wrapped with an outer package. However, with this method, the inner packaging material becomes softer, the tackiness of the surface increases, fusion occurs at the contact surface between the inner packaging material and the outer packaging material, and the product remains stuck or blocked even after cooling. Therefore, there is a problem in that it becomes difficult or impossible to open the outer packaging material when opening the package (when using a medical solution).

[0005] Therefore, at present, there is often no choice but to rely on the method of sterilizing the inner packaging material containing the medicinal solution and then wrapping it with an outer packaging material. Difficult to guarantee.

[0006]

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a novel base material for medical containers. Another object of the present invention is to solve the above-mentioned problems associated with conventional materials and to provide a base material for medical containers that has an excellent balance of transparency, flexibility, and heat resistance.

[0007]

[Means for Solving the Problems] The above object is to provide a laminate comprising polybutene-1 (A) and a low density polyethylene polymer and/or an ethylene-vinyl acetate copolymer (B), the innermost layer and/or Alternatively, the present invention can be achieved by a base material for a medical container characterized in that the outermost layer is formed from (A).

[0008] The present invention also provides that the laminate consists of three layers,
The inner layer and the outer layer of the laminate are formed from (A) and have a wall thickness of 5 to 100 μm, and the intermediate layer of the laminate is formed from (B) and have a wall thickness of 100 to 500 μm.
This figure shows a base material for medical containers that is m. The present invention also provides that the laminate consists of two layers, and the inner layer or outer layer is (A).
and has a wall thickness of 5 to 200 μm, and the outer layer or inner layer is formed of (B) and has a wall thickness of 100 to 200 μm.
This shows a base material for medical containers having a thickness of 500 μm. The present invention also provides a base material for medical containers in which polybutene-1 has a melting point of 118°C or higher. The present invention further includes:
Low density polyethylene polymer has a density of 0.93g/cm
High pressure low density polyethylene of 3 or less or density 0.8
This figure shows a base material for medical containers that is linear low density polyethylene with a weight of 7 to 0.93 g/cm3. The present invention further includes:
The vinyl acetate content of the ethylene-vinyl acetate copolymer is 5
-25% by weight of a medical container substrate.

[0009]

[Function] The base material for medical containers according to the present invention comprises polybutene-1 (hereinafter referred to as PB-1 polymer) (A) and low density polyethylene (hereinafter referred to as LDPE) polymer and/or ethylene-acetic acid. This is a laminate consisting of a vinyl copolymer (hereinafter referred to as EVA) (B), and the innermost layer and/or outermost layer is formed from (A).

[0010] In the medical container base material according to the present invention,
PB-1 polymers do not necessarily have a high melting point, but they have thermal stability that can withstand relatively high-temperature autoclaving, flexibility comparable to low-density polyethylene, good transparency, and adhesion with polyethylene polymers. are doing. For this reason,
Sheets or tubes obtained from PB-1 polymers have excellent transparency, flexibility, and heat resistance. Furthermore, in the base material for medical containers according to the present invention,
Since LDPE polymers and EVA have excellent flexibility, sheets or tubes made of these polymers have excellent flexibility. Therefore, the base material for medical containers of the present invention includes PB-1 polymer (A) and L
By taking advantage of the above-mentioned properties of the DPE polymer and/or EVA (B) in a well-balanced manner, it is possible to achieve a good balance between transparency, flexibility, and heat resistance.

The PB-1 polymer (A) used in the present invention has isotactic polybutene-1 as its main component, and in addition to homopolymers, it also contains ethylene,
Propylene, 1-pentene, 1-hexene, octene-
Copolymers typically include those obtained by copolymerizing a small amount of α-olefins such as 1,4-methylpentene-1, and are generally produced by known methods. When the PB-1-based polymer is a copolymer, these comonomers are introduced to improve the flexibility, transparency, etc. of PB-1, but the introduction of the comonomers increases the melting point (
The melting point of PB-1 is 125 to 130° C.) If the melting point of PB-1 is too low, the heat resistance will deteriorate, which is not preferable. Therefore, the amount of the comonomer introduced is such that the melting point of the polymer is 1.
It is desirable to suppress the temperature to 18°C or higher, more preferably 120°C or higher. Furthermore, considering the moldability and mechanical properties of the product (base material for medical containers consisting of laminates), the temperature of the PB-1 polymer used in the present invention is 19
Melt flow rate at 0°C and a load of 2.16 kg (
MFR) is 0.2-30, more preferably 0.5-2
It is 5.

The polymer component (B) in the present invention is L
This component is made of DPE polymer and/or EVA and softens the laminate. The LDPE polymer mentioned here includes not only high-pressure low-density polyethylene, but also
Propylene, butene-1, pentene-1, hexene-1
A specific example is linear low-density polyethylene produced by a low-pressure method using α-olefins such as , octene-1, and 4-methylpentene-1 as a copolymerization component. In terms of flexibility, the former has a density of 0.93 g/cm3 or less, more preferably 0.91 to 0.93 g/cm3, and the latter has a density of 0.87 to 0.93 g/cm3, more preferably 0.
．． A material having a density of about 88 to 0.92 g/cm3 is preferably used. Further, the EVA used in the present invention is also a polymer obtained by a commonly known method, and the content of the vinyl acetate component in the EVA is 5 to 25% by weight, more preferably 7 to 20% by weight.

Further, the polymer component (B) used in the present invention may be a mixture of an LDPE polymer and EVA, and in this case, the LDPE polymer and EVA
The ratio by weight is from 90:10 to 10:90, more preferably from 80:20 to 20:80.

Furthermore, the MFR of the polymer component (B) used in the present invention at a temperature of 190° C. and a load of 2.16 kg is 0, considering moldability, mechanical properties, etc.
．． It is 1-30, more preferably 0.3-25.

The base material for medical containers of the present invention is a laminate consisting of a polymer component (A) and a polymer component (B), the innermost layer and/or the outermost layer being formed from (A). . In order to ensure thermal stability sufficient to withstand high-pressure steam sterilization, a heat-resistant PB-1 polymer forms at least the innermost layer or the outermost layer. Specifically, three types of body shapes can be considered. In other words, ■
In a laminated structure with three or more layers, the innermost layer and the outermost layer are the components (
(A) in which the innermost layer is formed of (A) and the outermost layer is formed of another polymer in a laminated structure of two or more layers, and (ii) in a laminated structure of two or more layers, The outer layer is made of (A) and the innermost layer is made of another polymer. Form (2) is the most excellent in terms of heat resistance, but forms (2) and (2) are also possible. For example, when sterilizing a container (bag) that does not contain a medical solution, the innermost layers (inner walls) come into direct contact with each other, so
Although it is easy to block, the outermost layer (surface) contains water vapor and water droplets, which act as stick inhibitors, so blocking is relatively difficult to occur, making the form shown in (3) possible. For example, when an inner packaging material containing a medical solution is wrapped in an outer packaging material such as a polypropylene film or a polyamide film and sterilized using high-pressure steam, the innermost layer of the inner packaging material contains the pharmaceutical solution and cannot be directly contacted. However, there is a concern that a blocking phenomenon may occur between the outermost layer of the inner packaging material and the inner wall of the outer packaging material, so the container used as the inner packaging material should be in the form It also becomes possible.

[0016] In addition, the above-mentioned other polymer used when adopting the form (1) or (2) as the form of the laminate in the base material for medical containers of the present invention is preferably (B), but three-layer In the case of the above laminated structure, other polymers may be used. Other polymers include, but are not particularly limited to, polyethylene, polypropylene, poly-4-methylpentene-1, ethylene-vinyl alcohol copolymer, polyvinylidene chloride, nylon 6, nylon 8, nylon 12, nylon 66, nylon 610, poly-m-xylylene adipamide, polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate, poly-1,4-cyclohexylene dimethylene terephthalate, etc., and co-products containing these as main components. Examples include polymers.

In the present invention, component (A) may be used not only as the innermost layer or the outermost layer, but also as an intermediate layer, and as described above, component (A) and polymer components other than component (B) may be used. Although some layers of the laminate may be formed, considering the simplicity of the structure of the molding device, productivity, etc., the base material for medical containers of the present invention has a three-layer structure (in the case of ① above) or It is preferable to have a two-layer structure (in (1) and (2) above, the outer layer and inner layer are (B), respectively). In this case, in case (2), the inner layer and outer layer formed from (A) each have a thickness of 5 to 100 μm, more preferably 10 to 80 μm.
μm, the thickness of the intermediate layer formed from (B) is 100 to 5
00 μm, more preferably 120 to 400 μm. In addition, in ■ and ■, the layer formed from (A) has a thickness of 5 to 200 μm, more preferably 10 to 150 μm.
μm, the layer formed from (B) is 100 to 500 μm
, more preferably 120 to 400 μm. These wall thicknesses are appropriately adjusted depending on the flexibility and heat resistance required for the use of the base material for medical containers.

[0018] The medical container in the present invention refers to a container (bag) or connecting pipe (tube) for storing or transporting liquids used in medical treatment such as blood or medicinal solutions. It is manufactured by a commonly known method, such as injection molding, extrusion molding, sheet molding, blow molding, inflation molding, T-die molding, lamination molding, or a combination thereof. For example, if the above product is a bag, (A) and (B) are melted separately and multilayer extrusion molded using a T-die or inflation die at a polymer temperature of about 160 to 230°C, and the resulting sheet is obtained. (or the film) may be processed into a predetermined shape by appropriately applying techniques such as cutting and heat sealing. During extrusion, a method is preferably used in which the sheet is cooled with water or a casting roller in order to prevent a decrease in transparency due to crystallization.

Furthermore, when the above product is a tube,
Preferably, the tube is manufactured by extrusion, and in this case, the extruded tube is preferably quenched with water.

Specific examples of the shape of the sheet or tube in the present invention include unstretched sheets, uniaxially stretched sheets, biaxially stretched sheets, etc., but unstretched sheets are preferable in consideration of flexibility.

One of the purposes of the present invention is to improve heat resistance, especially to prevent blocking during high-pressure steam sterilization, but in order to improve the effect, the inner and outer surfaces of the container may be roughened by embossing or the like. In addition to the addition of an anti-blocking agent or the addition of an anti-blocking agent, a cross-linking treatment using radiation or an organic peroxide may also be applied.

[0022]Furthermore, within the scope of the spirit of the present invention,
Other polymers, plasticizers, inorganic fillers, stabilizers, etc. may be added to each layer, and in some cases, a polymer with good adhesion to (A) and (B) may be used as an intermediate layer.

The pharmaceutical solution of the present invention is not particularly limited, but includes, for example, physiological saline, electrolyte solution,
Preferred examples include dextran preparations, mannitol preparations, saccharide preparations, and amino acid preparations.

[0024] Also, high-pressure steam sterilization is usually performed at a gauge pressure of 0.
．． 100-125℃ under pressure of 5-2.5kg/cm2
It is carried out for 10 to 60 minutes at a temperature of .

[0025] Regarding the method of sterilizing the container of the present invention,
Other sterilization methods such as radiation sterilization may also be applied.

[0026]

[Examples] The present invention will be explained in more detail below with reference to Examples and Comparative Examples.

Examples 1 to 5, Comparative Examples 1 and 2 (1) Experimental method (1) Polymers used: The polymers shown in Table 1 were used in combination.

[0028] ■Preparation of sheet: The melted pellets of ■ are supplied to two types of three-layer multilayer T-die using an extruder, and
It was extruded at 70 to 190°C, and the film thus obtained was cooled with a casting roller maintained at 15°C, trimmed, and wound into a sheet with a width of 200 mm at a speed of 10 m/min (composition and The thickness of the sheet is shown in Table 2).

■Measurement of sheet flexibility: JIS K7
The tensile modulus was measured according to 113 and used as a measure of flexibility.

■Measurement of sheet transparency: JIS K6
714 (1958), the parallel light transmittance was measured.

■ Measurement of heat resistance (blocking resistance) of the sheet: Cut the sheet into a size of 150 mm x 200 mm, stack two sheets and heat seal on all sides to make a bag, and then 0.5 g A load (stainless steel plate) was placed so that a pressure of /cm2 was applied. In this state, it was placed in a retort type high-pressure steam sterilizer and heat-treated at a gauge pressure of 1.8 kg/cm 2 and a temperature of 110° C. or 120° C. for 30 minutes. After cooling, it was determined whether a blocking phenomenon occurred between the sheets and between the sheets and the stainless steel plate.

[0032] Heavy metal and eluate test: Each sheet was tested in accordance with the Japanese Pharmacopoeia general test method ``Test method for plastic containers for infusion''.

[0033]

[Table 1]

(2) Experimental results ■Multilayer extrusion molding of the sheet went very smoothly, with no occurrence of foreign matter or
No foaming was observed, and sheets with high uniformity were obtained in all compositions.

[0035] In all compositions, it was confirmed that heavy metals and leached substances complied with the Japanese Pharmacopoeia.

■ According to the relationship between the sheet composition and the properties of each sheet shown in Table 2, the sheet formed with the composition specified in the present invention has an excellent balance of flexibility, transparency, and heat resistance, and is suitable for medical containers. It was found to be suitable as a base material for

[0037]

[Table 2]

Example 6 A film made of (A1) with a thickness of 50 μm and a film made of (A1) with a thickness of 300 μm
A bag (approximately 14 cm×
30 cm), and 700 ml of physiological saline was contained and sealed. This was used as an inner packaging material, wrapped in a 100 μm thick polypropylene film (outer packaging material), vacuum packaged, and then sterilized using a retort type high-pressure steam sterilizer at a temperature of 110°C and a gauge pressure of 1.7.
It was sterilized for 1 hour under the condition of kg/cm2.

As a result, no blocking phenomenon was observed between the inner wrapping material and the polypropylene film in the bag after cooling to room temperature.

Comparative Example 3 Example 6 except that a sheet consisting of a 50 μm thick film made of (C1) (outer layer) and a 300 μm thick film made of (B1) (inner layer) was used as the inner wrapping material. An experiment was conducted in the same manner.

As a result, in the bag after cooling to room temperature, a strong blocking phenomenon was observed between the inner wrapping material and the polypropylene film.

[0042]

As described above, the present invention provides a laminate comprising polybutene-1 (A) and a low-density polyethylene polymer and/or an ethylene-vinyl acetate copolymer (B), the innermost layer and This is a base material for a medical container, characterized in that/or the outermost layer is formed from (A). The base material for medical containers of the present invention is polybutene-
It is produced by skillfully utilizing the above-mentioned excellent properties of type 1 polymer (A), and has satisfactory performance in terms of flexibility, transparency, heat resistance, hygiene, etc., and also has good productivity. Therefore, its industrial value is high.

Claims (6)

[Claims] Claim 1: A laminate comprising polybutene-1 (A) and a low-density polyethylene polymer and/or an ethylene-vinyl acetate copolymer (B), the innermost layer and/or the outermost layer being formed from (A). A base material for medical containers characterized by: 2. The laminate consists of three layers, the inner layer and the outer layer of the laminate are formed from (A), and each has a wall thickness of 5 to 100 μm, and the middle layer of the laminate is made of (B).
The base material for a medical container according to claim 1, wherein the base material is formed from a polyester resin and has a wall thickness of 100 to 500 μm. 3. The laminate consists of two layers, the inner layer or the outer layer is formed from (A), and has a wall thickness of 5 to 200 μm.
The base material for a medical container according to claim 1, wherein the outer layer or the inner layer is formed from (B) and has a wall thickness of 100 to 500 μm. 4. The base material for medical containers according to claim 1, wherein the polybutene-1 has a melting point of 118° C. or higher. 5. The medical treatment according to claim 1, wherein the low-density polyethylene polymer is high-pressure low-density polyethylene with a density of 0.93 g/cm3 or less or linear low-density polyethylene with a density of 0.87 to 0.93 g/cm3. Base material for containers. 6. The base material for a medical container according to claim 1, wherein the vinyl acetate content of the ethylene-vinyl acetate copolymer is 5 to 25% by weight.