JP2000239635A - Adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive which keeps its adhesion even when subjected to various sterilization treatments when used to bond polyvinyl chloride substitutes in medical devices, sanitary products and medical supplies and which can be used easily. SOLUTION: An adhesive comprises a solution obtained by dissolving at least one of those selected from block copolymers comprising (A) polymer blocks comprising aromatic vinyl compound units and (B) polymer blocks comprising conjugated diene units, the content of the aromatic vinyl compound units being 5-40 wt.%, and hydrogenated products thereof in an organic solvent. The polymer block (B) is preferably at least one polymer block selected from the group consisting of (b1) polyisoprene blocks having 1,2-linkage and 3,4-linkage content of 3 mol% or more, (b2) polymer blocks comprising 5-95 wt.% of isoprene unit and 95-5 wt.% of butadiene unit having a 1,2-linkage and 3,4-linkage content of 20 mol% or more and (b3) polybutadiene blocks having a 1,2-linkage content of 35 mol% or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an adhesive.
The adhesive of the present invention has excellent adhesiveness to a resin, and does not decrease its adhesive strength even after sterilization. Therefore, it is particularly useful as an adhesive for medical tools, sanitary materials, and medical supplies.

[0002]

2. Description of the Related Art Conventionally, polyvinyl chloride has been widely used for medical and welfare purposes as well as for industrial use and general household use. In particular, disposable medical devices such as blood bags, blood tubes, infusion bags, Most of infusion tubes, blood circuits, catheters, and the like are manufactured using polyvinyl chloride. However, polyvinyl chloride contains a relatively large amount of a plasticizer such as dioctyl phthalate, and the problem of elution of the plasticizer into blood or an infusion solution has been pointed out from the viewpoint of safety of medical devices.

[0003] On the other hand, from the viewpoint of infection prevention, disposable medical devices have been promoted, and it is legally required that these medical devices be incinerated after use. It is known that polyvinyl chloride, when supplied with sufficient oxygen and burned at a temperature of 850 to 900 ° C., eventually becomes carbon dioxide, water and hydrogen chloride, and hardly generates toxic chlorine-based substances such as dioxin. However, there is a problem of environmental pollution due to dioxin and other toxic chlorine-based substances due to a shortage of incinerators that can withstand high temperatures and a shortage of dioxin treatment equipment.

[0004] For this reason, the development of other materials that can substitute for polyvinyl chloride as materials for medical use as well as for industrial use and general household use has been intensively studied, and ethylene vinyl alcohol copolymer (EVA), Polypropylene (P
P), thermoplastic resins (TPE) and other resins containing no chlorine are being put to practical use.

When these polyvinyl chloride substitute materials are used for medical applications, they are required to have the same flexibility, transparency, chemical resistance, abrasion resistance, blood compatibility and adhesiveness as polyvinyl chloride. Blood leakage, especially if the adhesion of the material is poor
Since it sometimes leads to fatal accidents such as leakage of infusion, aeration, infection, etc., and greatly affects the reliability of medical devices, development of an adhesive that adheres well to a polyvinyl chloride substitute material is desired.

However, commercially available epoxy adhesives and so-called "flash adhesives" may not show sufficient adhesive strength depending on the type of resin to be bonded. In some cases, the adhesive force changes due to a sterilization operation (ethylene oxide gas sterilization, autoclave sterilization, gamma ray sterilization, electron beam sterilization, etc.) performed after the manufacture of the medical device, and the product cannot be used clinically.

Further, thermoplastic elastomers are often used as hot melt adhesives (Japanese Patent Laid-Open No. 2-15 / 1990).
No. 3986). Since this adhesive does not contain water or a solvent, it does not require a drying step, but requires a special device called a large-scale applicator for melting and applying the resin.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a medical device such as a blood bag, a blood tube, an infusion bag, an infusion tube, a blood circuit, a catheter, a sanitary article, a disposable diaper, and a surgical device. Adhesion that can be easily used without reducing the adhesive strength to various sterilization methods when a polyvinyl chloride substitute material used for clothes, hospital disposable sheets, and other medical supplies is bonded. To provide an agent.

[0009]

According to the present invention, an object of the present invention is to provide a polymer block (A) comprising an aromatic vinyl compound unit (hereinafter sometimes referred to as a polymer block A) and a conjugate. A polymer block (B) comprising diene units (hereinafter sometimes referred to as a polymer block B), wherein the content of the aromatic vinyl compound unit is 5
This is attained by providing an adhesive comprising a solution obtained by dissolving at least one selected from a block copolymer and a hydrogenated product thereof in an organic solvent in an amount of about 40% by weight.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The polymer block A in the above block copolymer is composed of aromatic vinyl compound units. Examples of the aromatic vinyl compound for deriving such a unit include styrene, α-methylstyrene, 1-vinylnaphthalene, 3-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, and 2-ethyl-4-. Benzyl styrene, 4- (phenylbutyl) styrene, etc. are mentioned, and styrene is preferable from a viewpoint of availability and economical efficiency.

The number average molecular weight of the polymer block A is not particularly limited, but is preferably in the range of 2,500 to 20,000.

The content of the aromatic vinyl compound unit in the block copolymer is in the range of 5 to 40% by weight.
When the content of the aromatic vinyl compound unit in the block copolymer is less than 5% by weight, the adhesive strength of the adhesive becomes insufficient, and when the content of the aromatic vinyl compound unit exceeds 40% by weight, the adhesion becomes poor. When it is used as an agent, the viscosity becomes high, so that the coatability of the adhesive becomes poor and the adhesive strength becomes insufficient.

The polymer block B in the above block copolymer is composed of conjugated diene units. Conjugated dienes that induce such units include isoprene, butadiene, furan, cyclopentadiene, and the like,
Isoprene and butadiene are preferred from the viewpoint of availability and economy.

As the polymer block B, a polyisoprene block (b1) having a 1,2-bond and 3,4-bond content of at least 3 mol% from the viewpoint of increasing the adhesive strength.
(Hereinafter, this may be referred to as a polyisoprene block (b1)), which is composed of 5 to 95% by weight of isoprene units and 95 to 5% by weight of butadiene units, and has a 1,2-bond and a 3,4-bond content. Is 20 mol% or more (hereinafter sometimes referred to as isoprene-butadiene block (b2)) and 1,2-
At least one polymer block selected from the group consisting of polybutadiene blocks (b3) having a bond content of 35 mol% or more (hereinafter sometimes referred to as polybutadiene blocks (b3)) is preferable.

The content of 1,2-bonds and 3,4-bonds (vinyl bond content) in the polyisoprene block (b1) is preferably at least 3 mol%, more preferably at least 10 mol%.
More preferably, it is more preferably at least 40 mol%. The content of 1,2-bonds and 3,4-bonds in the polyisoprene block (b1) is 3 mol%
If it is less than 3, the adhesive strength tends to decrease. The number average molecular weight of the polyisoprene block (b1) is not particularly limited, but is preferably in the range of 10,000 to 200,000.

Isoprene-butadiene block (b2)
Is 5-95% by weight of isoprene units and 9 butadiene units
5 to 5% by weight, and the content of 1,2-bond and 3,4-bond (vinyl bond content) in the block is 20%.
It is preferably at least 40 mol%, more preferably at least 40 mol%. The isoprene-butadiene block (b2) has a 1,2-bond and a 3,4-bond content of 20.
If the amount is less than mol%, the adhesive strength tends to decrease. The polymerization form of isoprene and butadiene in the isoprene-butadiene block (b2) is not particularly limited, and may be any form such as random, block, or tapered. Also, isoprene-butadiene block (b2)
Although the number average molecular weight of is not particularly limited,
Preferably it is in the range of 200,000.

The content of 1,2-bonds (vinyl bond content) in the polybutadiene block (b3) is preferably at least 35 mol%, more preferably at least 45 mol%, and more preferably at least 60 mol%. More preferably, there is. 1,2- in the polybutadiene block (b3)
When the content of the bond is less than 35 mol%, the block copolymer tends to crystallize, the solubility decreases, and the adhesive strength tends to decrease. Although the number average molecular weight of the polybutadiene block (b3) is not particularly limited, it is 10,000 to 200,0.
It is preferably in the range of 00.

The bonding mode of each polymer block in the above block copolymer is not particularly limited, and may be linear, branched or any combination thereof. If a specific example of the molecular structure of the block copolymer is shown, A- (BA)
n, (AB) n (where A and B represent a polymer block A and a polymer block B, respectively, and n is an integer of 1 or more) and the like. In addition, as the block copolymer, a star (for example, [(AB) mX], where m is an integer of 2 or more, X is obtained by using divinylbenzene, a tin compound, a silane compound, or the like as a coupling agent.
Represents a residue of a coupling agent).

As the block copolymer, those having the above-mentioned various molecular structures may be used alone, or different molecular structures such as a mixture of a triblock type and a diblock type may be used. May be used in combination of two or more. The number average molecular weight of such a block copolymer is
It is preferably in the range of 30,000 to 300,000.

The above block copolymer can be produced, for example, by the following methods (a) to (c). (A) A method of polymerizing an aromatic vinyl compound using an alkyllithium compound as an initiator and then sequentially polymerizing a conjugated diene compound and an aromatic vinyl compound. (B) A method in which an aromatic vinyl compound and subsequently a conjugated diene compound are polymerized, and the obtained block copolymer is coupled using a coupling agent. (C) A method of polymerizing a conjugated diene compound using a dilithium compound as an initiator, and then sequentially polymerizing an aromatic vinyl compound. As the alkyl lithium compound in the above method,
A compound having an alkyl group having 1 to 10 carbon atoms is used. Among them, methyl lithium, ethyl lithium, pentyl lithium, n-butyl lithium, s-butyl lithium,
t-Butyl lithium is preferred.

Examples of the coupling agent include halogen compounds such as dichloromethane, dibromomethane, dichloroethane, dibromoethane, dibromobenzene and tin tetrachloride; ester compounds such as phenyl benzoate and ethyl acetate; divinylbenzene and various silane compounds. No.

Examples of the dilithium compound include naphthalenedilithium and dilithiohexylbenzene.

The amount of the above-mentioned initiator or coupling agent to be used is appropriately determined according to the molecular weight of the target block copolymer.
For 0 parts by weight, the initiator is 0.01 to 0.2 parts by weight,
The coupling agent is used in the range of 0.04 to 0.8 parts by weight.

A polyisoprene block (b1);
The vinyl bond content in the isoprene-butadiene block (b2) and the polybutadiene block (b3) can be controlled by using a Lewis base as a cocatalyst during the polymerization. Examples of such Lewis bases include ethers such as dimethyl ether, diethyl ether and tetrahydrofuran; glycol ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether; triethylamine;
N, N, N ', N'-tetramethylethylenediamine,
Examples include amine compounds such as N-methylmorpholine. The amount of the Lewis base used is preferably in the range of 0.1 to 1,000 mol per mol of lithium atom in the polymerization initiator.

In the polymerization, an organic solvent inert to the polymerization initiator is used as a solvent. As such a solvent, it is preferable to use an aliphatic hydrocarbon having 6 to 12 carbon atoms, such as hexane and heptane, an alicyclic hydrocarbon such as cyclohexane and methylcyclohexane, and an aromatic hydrocarbon such as benzene.

In order to improve the adhesive strength of the adhesive of the present invention, it is preferable to hydrogenate the carbon-carbon double bond of the block copolymer to make it a single bond. As the hydrogenation method, for example, a known method such as a method in which a block copolymer is dissolved in a solvent inert to the reaction and hydrogen in a molecular state is reacted using a hydrogenation catalyst is used. Examples of the hydrogenation catalyst used here include a heterogeneous catalyst in which a metal such as nickel, platinum, palladium, ruthenium, and rhodium is supported on a carrier such as carbon, alumina, and diatomaceous earth; and a Group VIII catalyst such as nickel and cobalt. Ziegler catalysts consisting of a combination of an organometallic compound consisting of the above metals and an organoaluminum compound such as triethylaluminum and triisobutylaluminum or an organolithium compound, and a transition metal bis (cyclopentadienyl) such as titanium, zirconium and hafnium A metallocene catalyst comprising a combination of a compound and an organometallic compound such as lithium, sodium, potassium, aluminum, zinc or magnesium is used. The hydrogenation is usually carried out at a hydrogen pressure in the range of normal pressure to 200 kg / cm ² and a reaction temperature in the range of normal temperature to 250 ° C. The reaction time is usually 0.1 to 100 hours. The hydrogenated block copolymer produced by hydrogenation can be prepared by (i) coagulating the reaction mixture with methanol or the like and then heating or drying under reduced pressure, or (ii) pouring the reaction solution into boiling water and azeotropically evaporating the solvent. After being subjected to so-called steam stripping for removal by heating, it is obtained by heating or drying under reduced pressure.

The adhesive of the present invention can be produced by dissolving the block copolymer thus obtained in an organic solvent to form a solution. Examples of the organic solvent include toluene, xylene, tetrahydrofuran, n-hexane, cyclohexanone, cyclohexane, methylcyclohexane, isoamyl acetate, n-heptane,
From the viewpoint of easily dissolving the block copolymer in an organic solvent, toluene, xylene, tetrahydrofuran, cyclohexanone, cyclohexane, and methylcyclohexane are preferred, and toluene and tetrahydrofuran are more preferred.

The concentration of the block copolymer or its hydrogenated product in the solution of the adhesive of the present invention depends on the solubility of the block copolymer or its hydrogenated product in an organic solvent. 3 ~ from the viewpoint of coating workability
It is preferably in the range of 30% by weight, more preferably in the range of 10 to 20% by weight.

The adhesive of the present invention has excellent adhesive strength to various resins which substitute for polyvinyl chloride, and particularly has high adhesive strength to resins such as polyolefin, a mixture of polyolefin and styrene / diene block copolymer, and polycarbonate. , Blood bags, blood tubes, infusion bags,
It is useful as an adhesive for medical devices such as infusion tubes, blood circuits and catheters; sanitary materials such as sanitary products and disposable diapers; and medical products such as surgical clothing and hospital disposable sheets. Further, the adhesive of the present invention can withstand the temperature of autoclave sterilization (121 ° C.) and does not reduce the adhesive strength due to the sterilization treatment. Therefore, the adhesive is suitable as an adhesive to be used for medical devices requiring sterilization.

[0030]

EXAMPLES Hereinafter, the present invention will be described in detail by reference examples and examples, but the present invention is not limited thereto.

Reference Examples 1 and 2: Preparation of Block Copolymer Styrene was polymerized at 60 ° C. in a pressure-resistant container replaced with dry nitrogen using cyclohexane as a solvent and s-butyllithium as a polymerization initiator. Thereafter, tetrahydrofuran is added as a Lewis base, and then isoprene and styrene are sequentially polymerized to form styrene-isoprene-
Two types of styrene type block copolymers were obtained. Styrene content of the resulting block copolymer, number average molecular weight,
The vinyl bond content is shown in Table 1 below.

Reference Example 3 Production of Hydrogenated Block Copolymer The styrene-isoprene-styrene type block copolymer obtained in Reference Example 2 was treated in cyclohexane with palladium carbon as a catalyst at a hydrogen pressure of 20 kg / cm ² . By hydrogenation, a hydrogenated block copolymer was obtained. Styrene content of the obtained hydrogenated block copolymer, number average molecular weight,
Table 1 below shows the vinyl bond content and the degree of hydrogenation.

Reference Example 4 Production of Hydrogenated Block Copolymer A mixture of styrene, isoprene and butadiene [isoprene / butadiene] was prepared in the same manner as in Reference Examples 1 and 2 using s-butyllithium and tetrahydrofuran in a cyclohexane solvent. = 60/40 (weight ratio)] and styrene were sequentially polymerized to obtain a styrene- (isoprene / butadiene) -styrene type block copolymer. The obtained block copolymer was hydrogenated in the same manner as in Reference Example 3 to obtain a hydrogenated block copolymer. Table 1 below shows the styrene content, number average molecular weight, vinyl bond content, and hydrogenation ratio of the obtained hydrogenated block copolymer.

Reference Examples 5 and 6: Production of Hydrogenated Block Copolymer In a pressure-resistant container replaced with dry nitrogen, styrene was polymerized using cyclohexane as a solvent and s-butyllithium as a polymerization initiator. , Isoprene and styrene were sequentially polymerized to obtain a styrene-isoprene-styrene type block copolymer. Further, in cyclohexane, using palladium carbon as a catalyst, hydrogen pressure 20 kg / cm
By hydrogenation in ² , a hydrogenated block copolymer was obtained. Table 1 below shows the styrene content, number average molecular weight, vinyl bond content, and hydrogenation ratio of the obtained hydrogenated block copolymer.

The styrene content, number average molecular weight, vinyl bond content and hydrogenation rate were measured by the following methods. Styrene content: calculated from the weight of each monomer component used in the polymerization. Number average molecular weight: The number average molecular weight in terms of polystyrene was determined by GPC measurement. Vinyl bond content: The block copolymer before hydrogenation was dissolved in deuterated chloroform (CDCl ₃ ) to give ¹ H-N
The MR spectrum was measured, and the 1,2-bond or 3,4-
The vinyl bond content was calculated from the size of the peak corresponding to the bond. Hydrogenation rate: The iodine value of the block copolymer before and after hydrogenation was measured and calculated from the measured value.

[0036]

[Table 1]

Examples 1 to 4 Each of the block copolymers obtained in Reference Examples 2 to 5 was converted into a 20% by weight toluene solution to obtain an adhesive.

Examples 5 to 7 Each of the block copolymers obtained in Reference Examples 1 to 3 was converted into a 20% by weight solution of tetrahydrofuran to obtain an adhesive.

Comparative Example 1 The block copolymer obtained in Reference Example 6 was used at a concentration of 20% by weight.
An adhesive was obtained by preparing a toluene solution of

Test Example 1 Two 1 cm × 2 cm rectangular polypropylene sheets (thickness: 100 μm) were cut out and obtained on one half (1 cm ² ) of Examples 1-3, 5-7 or Comparative Example 1. An adhesive was applied in an amount of 15 μl, and the half surface was covered with a Teflon sheet having a thickness of 100 μm. The sample was left at room temperature (about 25 ° C.) for 24 hours or longer to prepare a sample (unsterilized) for measuring the adhesive peel strength. In addition, autoclave sterilization (121
° C, 20 minutes) and ethylene oxide gas sterilization (60
C. for 3 hours) to prepare a sample for measuring adhesive peel strength. Autograph (AGS-50A manufactured by Shimadzu Corporation) of the peel strength before and after sterilization of the sample prepared above.
(Speed = 10 mm / min, number of samples n =
3) A significant difference test before and after sterilization was performed by t-test. Table 2 shows the results.

[0041]

[Table 2]

From the results in Table 2 above, it can be seen that the adhesives of Examples 1 to 3 and 5 to 7 have excellent adhesive strength. In particular, it can be seen that the peel strength when the adhesive of Example 2 was used was significantly higher after autoclave sterilization than before sterilization.

Test Example 2 A sheet (thickness: 100 μm) composed of a mixture of the hydrogenated block copolymer and polypropylene (mixing ratio: 30:70) obtained in Reference Example 3 and a polycarbonate sheet (thickness: 100 μm) Cut out into a 1 cm × 2 cm rectangular shape, apply 15 μl of the adhesive obtained in Example 2 to one half (1 cm ² ), cover the half with a Teflon sheet having a thickness of 100 μm, and bond the two sheets together with a slide glass. It was sandwiched and fixed with clips. The sample was left at room temperature (about 25 ° C.) for 24 hours or longer to prepare a sample (unsterilized) for measuring the adhesive peel strength.
In addition, the above sample was subjected to autoclave sterilization (121 ° C., 20
Min) and ethylene oxide gas sterilization (60 ° C., 3 hours) to prepare a sample for measuring adhesive peel strength. For the sample prepared above, the peel strength before and after sterilization was measured using an autograph (AGS-50A manufactured by Shimadzu Corporation) (speed = 10 mm / min, number of samples n = 3), and two types were determined by t-test. Table 3 shows the results of a significant difference test before and after sterilization.

[0044]

[Table 3]

Test Example 3 A sheet (thickness: 100 μm) composed of a mixture of the hydrogenated block copolymer and polypropylene (mixing ratio: 30:70) obtained in Reference Example 3 was cut into a rectangular shape of 1 cm × 2 cm. 1 cm ² ) was coated with 15 μl of the adhesive obtained in Examples 2 to 4 or Comparative Example 1, and covered on one half with a Teflon sheet having a thickness of 100 μm. did. The sample was left at room temperature (about 25 ° C.) for 24 hours or longer to prepare a sample (unsterilized) for measuring the adhesive peel strength. The sample was subjected to autoclave sterilization (121 ° C., 20 minutes) and ethylene oxide gas sterilization (60 ° C., 3 hours) to prepare a sample for measuring adhesive peel strength. For the sample prepared above, the peel strength before and after sterilization was measured with an autograph (AGS-Shimadzu Corporation).
50A) (velocity = 10 mm / min, number of samples n = 3), and the results of performing a significant difference test between before and after sterilization by t-test are shown in Table 4.

[0046]

[Table 4]

Test Example 4 Hydrogenated block copolymer of (polystyrene)-(1,4-polyisoprene)-(polystyrene) (“Septon 2004” manufactured by Kuraray Co., Ltd .; hereinafter referred to as “SEPS”) and polypropylene A sheet (thickness: 100 μm) made of the mixture (mixing ratio: 55:45) was cut into a rectangular shape of 1 cm × 2 cm, and the adhesive obtained in Examples 1 to 3 or Comparative Example 1 was applied to a half surface (cm ² ) of 15 μl. And half the thickness is 100μ
After covering with a Teflon sheet of m, the two sheets were stuck together, sandwiched between slide glasses, and fixed with clips. Room temperature (about 2
(5 ° C.) for 24 hours or more to prepare a sample (unsterilized) for measuring adhesive peel strength. The sample was subjected to autoclave sterilization (121 ° C., 20 minutes) and ethylene oxide gas sterilization (60 ° C., 3 hours) to prepare a sample for measuring adhesive peel strength. For the sample prepared above, the peel strength before and after sterilization was measured using an autograph (AGS-50A manufactured by Shimadzu Corporation) (speed = 10 mm / min,
The number of samples (n = 3) and the results of performing a significant difference test before and after sterilization by t-test are shown in Table 5.

[0048]

[Table 5]

Test Example 5 A sheet (thickness: 100 μm) comprising a mixture of the hydrogenated block copolymer obtained in Reference Example 3 and polypropylene (mixing ratio: 30:70) and a mixture of SEPS and polypropylene (mixing ratio: 55:45) ) (Thickness 100μm)
Was cut into a rectangular shape of 1 cm × 2 cm, 15 μl of the adhesive obtained in Example 2 or 4 was applied to one half (1 cm ² ), and the half was covered with a Teflon sheet having a thickness of 100 μm. The sheets were stuck together, sandwiched between slide glasses, and fixed with clips. The sample was left at room temperature (about 25 ° C.) for 24 hours or longer to prepare a sample (unsterilized) for measuring the adhesive peel strength.
In addition, the above sample was subjected to autoclave sterilization (121 ° C., 20
Min) and ethylene oxide gas sterilization (60 ° C., 3 hours), respectively, to prepare a sample for measuring adhesive peel strength. Autograph (AGS-50A manufactured by Shimadzu Corporation) of the peel strength before and after sterilization of the sample prepared above.
(Speed = 10 mm / min, number of samples n =
3), Table 6 shows the results of two types of significant difference test before and after sterilization by the t test.

[0050]

[Table 6]

Test Example 6 An in-dwelling catheter made of the following material was assembled.
A pull-out strength test before and after sterilization was performed. Sample: • Catheter part: Tube molded product (inner diameter 0.7 mm × outer diameter 1.15 mm) consisting of a mixture of hydrogenated block copolymer and polypropylene of Reference Example 3 (mixing ratio 20:80) • Intermediate adapter part: Reference A tube molded product (inner diameter 1.2 mm x outer diameter 2.65 mm) comprising a mixture of the hydrogenated block copolymer of Example 3 and polypropylene (mixing ratio 20:80)-Connector portion: Hydrogenated block copolymer weight of Reference Example 3 Molded article composed of a mixture of coalesced and polypropylene (mixing ratio 10:90) Adhesion of materials: Using the adhesive obtained in Example 2, insert portions in the order of the catheter section, the intermediate adapter section, and the connector section, respectively. Adhering to 1cm, room temperature (about 25
C.) for 24 hours or more to prepare a sample for a pull-out test. Sterilization treatment: Autoclave sterilization (121
° C, 20 minutes) and ethylene oxide gas sterilization (60
C., 3 hours). Measurement of pull-out strength: For the above sample, the pull-out strength before and after sterilization was autographed (AG manufactured by Shimadzu Corporation).
S-50A). The pull-out strength was measured using both ends of the catheter part and the connector part (speed = 10 m).
m / min, number of samples n = 3), two kinds of significance tests before and after sterilization were performed by t-test. Table 7 shows the results.

[0052]

[Table 7]

From the results shown in Table 7, it can be seen that the adhesive of Example 2 has a high adhesive strength, and this adhesive strength is significantly increased by autoclave sterilization as compared with before the sterilization.

[0054]

According to the present invention, blood bags, blood tubes, infusion bags, infusion tubes, blood circuits, medical devices such as catheters, sanitary products, sanitary materials such as disposable diapers, surgical clothing, and disposable sheets for hospitals. The present invention provides an adhesive which does not decrease the adhesive strength to various sterilization methods and can be used easily when a polyvinyl chloride substitute material used for medical supplies and the like is adhered.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kouichi Wada, Inventor Kuraray, 36, Kamisu-cho, Kashima-gun, Ibaraki Pref. (72) Inventor Mizuho Maeda 36 Towada, Kamisu-cho, Kashima-gun, Ibaraki F-term in Kuraray Co., Ltd. (reference) 4J040 DM011 HB02 HB03 HB19 HB43 JA02 KA23 LA06 NA02

Claims (4)

[Claims] 1. A block comprising a polymer block (A) comprising an aromatic vinyl compound unit and a polymer block (B) comprising a conjugated diene unit, wherein the content of the aromatic vinyl compound unit is 5 to 40% by weight. An adhesive comprising a solution obtained by dissolving at least one selected from a copolymer and a hydrogenated product thereof in an organic solvent. 2. A polyisoprene block (b1) wherein the polymer block (B) has a 1,2-bond and 3,4-bond content of at least 3 mol%, 5-95% by weight of isoprene units and butadiene Consisting of 95 to 5% by weight,
A polymer block (b2) having a bond and 3,4-bond content of at least 20 mol%, and a 1,2-bond content of 3
The adhesive according to claim 1, wherein the adhesive is at least one polymer block selected from the group consisting of a polybutadiene block (b3) having a mole percentage of 5% or more. 3. The adhesive according to claim 1, wherein 50 mol% or more of carbon-carbon double bonds in the polymer block (B) are hydrogenated. 4. The method according to claim 1, wherein the organic solvent is at least one selected from the group consisting of toluene, xylene, tetrahydrofuran, cyclohexanone, cyclohexane and methylcyclohexane. adhesive.