Catheter manufacturing method

Abstract

To provide a catheter manufacturing method capable of being excellently adhered and fixed by using an acrylic surgical tape.SOLUTION: A catheter manufacturing method having a silicone tube 11 has: a first step for forming a silicone tube 11; and a second step for forming an urethane coat layer 14 to at least a fixing part 20 of the silicone tube 11.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a catheter.

Background Art

[0002] In the medical field, catheters made of silicone rubber are used to introduce moisture, nutrients, etc. into the body or to discharge substances in the body to the outside. In addition, balloon catheters in which a balloon that expands and contracts is disposed at the tip (patient side) of the catheter are also widely used. After these catheters are inserted into the body, it is necessary to fix the part that comes out of the body to the body surface with a surgical tape from above so that the catheter does not come out or move. In the medical field, acrylic surgical tape is mainly used as such a surgical tape.

Summary of the Invention

Problems to be Solved by the Invention

[0003] However, acrylic surgical tape has a problem that its adhesiveness to a silicone catheter is not so high. Therefore, it is conceivable to use silicone-based surgical tape instead of acrylic-based surgical tape. However, although silicone-based surgical tape has adhesiveness to a silicone catheter higher than that of acrylic-based surgical tape, it is expensive and the distribution volume is small. Further, even if silicone-based surgical tape is introduced, since acrylic-based surgical tape is mainly used in the medical field, there is a problem that it takes time and effort for management or confirmation work to properly use silicone-based surgical tape and acrylic-based surgical tape separately. The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for manufacturing a catheter that can be satisfactorily adhesively fixed using acrylic-based surgical tape.

Means for Solving the Problems

[0004] The manufacturing method of the catheter of the present invention is a method for manufacturing a catheter having a silicone tube, and includes a first step of forming a silicone tube and a second step of forming a urethane coat layer on at least a fixing portion of the silicone tube.

[0005] Before forming the urethane coat layer, a surface treatment may be performed on the surface of any fixing portion of the silicone tube.

[0006] The surface treatment is preferably UV irradiation, excimer UV irradiation, or plasma irradiation.

Advantages of the Invention

[0007] According to the manufacturing method of the catheter of the present invention, the catheter can be satisfactorily adhesively fixed with an acrylic surgical tape.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the catheter of the present invention will be described with reference to the drawings. The following embodiments are presented for illustrative purposes, and the present invention is not limited to the embodiments shown below.

[0010] [Manufacturing Method of Catheter] (First Step) As shown in FIG. 1(a), the first step is a step of forming a silicone tube 11. -Silicone Tube- The silicone tube 11 is made of silicone rubber. From the viewpoint of reducing pain during insertion into the body, the rubber hardness (JIS K 6253-3) of the silicone tube 11 is preferably A30 or more and A80 or less, and more preferably A40 or more and A70 or less.

[0011] The silicone tube 11 can be produced by primary extrusion molding and vulcanization treatment of a silicone rubber composition. The primary extrusion molding can be performed using a known horizontal extrusion molding machine and a vertical extrusion molding machine. From the viewpoint of preventing fine contact traces from remaining on the surface of the tube, it is preferable to use a vertical extruder and a vulcanizer in the extrusion molding process and the vulcanization treatment.

[0012] Examples of the silicone rubber composition include addition-curing type millable silicone rubber compositions.

[0013] -Addition-curing type millable silicone rubber composition- Examples of the addition-curing type millable silicone rubber composition include those containing (A) an organopolysiloxane represented by the following average composition formula (1) and (B) a filler. R 1 n SiO (4-n) / 2 …(1) In formula (1), n represents a positive number of 1.95 or more and 2.05 or less. Also, R 1 represents a substituted or unsubstituted monovalent hydrocarbon group, which may be the same or different. The number of carbon atoms of the hydrocarbon group is preferably 1 or more and 12 or less, and more preferably 1 or more and 8 or less.

[0014] R 1 Examples of R 1These hydrocarbon groups may be groups in which some or all of the hydrogen atoms they have are substituted with substituents. The substituents may be, for example, a halogen atom, a cyano group, etc. Examples of the hydrocarbon group having a substituent include a chloromethyl group, a trifluoropropyl group, a cyanoethyl group, etc.

[0015] (A) The organopolysiloxane preferably has a molecular chain end blocked with a trialkylsilyl group such as a trimethylsilyl group, a dialkylalkenylsilyl group such as a dimethylvinylsilyl group, a dialkylhydroxysilyl group such as a dimethylhydroxysilyl group, a trialkenylsilyl group such as a trivinylsilyl group, etc.

[0016] (A) The organopolysiloxane preferably has two or more alkenyl groups in the molecule. (A) The organopolysiloxane preferably has 0.001 mol% or more and 5 mol% or less (more preferably 0.01 mol% or more and 0.5 mol% or less) of alkenyl groups among R 1 The vinyl group is particularly preferred as the alkenyl group of (A) the organopolysiloxane.

[0017] (A) The organopolysiloxane can be obtained, for example, by co-hydrolytic condensation of one or two or more organohalosilanes, or by ring-opening polymerization of cyclic polysiloxanes such as trimers or tetramers of siloxane. (A) The organopolysiloxane may basically be a linear diorganopolysiloxane and may be partially branched. Also, (A) the organopolysiloxane may be a mixture of two or more having different molecular structures.

[0018] (A) The organopolysiloxane preferably has a kinematic viscosity at 25°C of 100 cSt or more, and more preferably 100000 cSt or more and 10000000 cSt or less. Also, the degree of polymerization of (A) the organopolysiloxane is preferably, for example, 100 or more, and more preferably 3000 or more and 10000 or less.

[0019] (B) As the filler, for example, silica-based fillers can be mentioned. Examples of the silica-based fillers include fumed silica, precipitated silica, etc.

[0020] As the silica-based filler, R 2 Si(OR 3 ) 3 The surface-treated silica-based filler surface-treated with a silane coupling agent represented by can be preferably used. Here, R 2 may be a group having a vinyl group or an amino group, and for example, may be a glycidyl group, a vinyl group, an aminopropyl group, a methacryloxy group, an N-phenylaminopropyl group, a mercapto group, etc. R 3 may be an alkyl group, and for example, may be a methyl group, an ethyl group, etc. The silane coupling agent can be easily obtained, for example, under the trade names "KBM1003", "KBE402", etc. manufactured by Shin-Etsu Chemical Co., Ltd. The surface-treated silica-based filler can be obtained by treating the surface of the silica-based filler with a silane coupling agent according to a conventional method. As the surface-treated silica-based filler, commercially available products may be used, and for example, products under the trade name "Zeothix 95" manufactured by J.M. HUBER Corporation can be mentioned.

[0021] The blending amount of the silica-based filler is preferably 11 parts by mass or more and 40 parts by mass or less, more preferably 15 parts by mass or more and 35 parts by mass or less, with respect to 100 parts by mass of (A) organopolysiloxane. Also, the average particle diameter of the silica-based filler is preferably 1 μm or more and 80 μm or less, more preferably 2 μm or more and 40 μm or less. The average particle diameter of the silica-based filler can be measured as the median diameter using a particle size distribution measuring device by the laser light diffraction method.

[0022] The addition-curing type moldable silicone rubber composition may contain, as additives, for example, silane coupling agents, antibacterial agents, auxiliary agents (chain extenders, crosslinking agents, etc.), catalysts, dispersants, foaming agents, anti-aging agents, antioxidants, pigments, colorants, processing aids, softeners, plasticizers, emulsifiers, heat resistance improvers, flame retardancy improvers, acid acceptors, thermal conductivity improvers, release agents, solvents, etc.

[0023] Side holes 13 are formed at the tip of the catheter 10. The side holes 13 communicate with the inner lumen 12 (see Figure 2). Through the inner lumen 12, introduction of moisture, nutrients, etc. into the body and discharge of substances in the body to the outside are carried out.

[0024] A contrast agent-containing portion in which the contrast agent is linearly blended along the longitudinal direction may be provided on the side surface of the silicone tube 11.

[0025] (Second step) As shown in FIGS. 1(b) and 2, the second step is a step of forming a urethane coat layer 14 on at least the fixing portion 20 of the silicone tube 11. The urethane coat layer 14 may be partially provided on the fixing portion 20 or may be provided on the entire silicone rubber tube 11. The urethane coat layer 14 can be formed by applying a urethane coat layer-forming composition containing at least a polyol, a polyisocyanate, and an organic solvent and then performing a heat treatment. Hereinafter, the constituent components of the urethane coat layer-forming composition will be described.

[0026] - Polyol - The polyol may be various polyols commonly used in the preparation of polyurethanes, and is preferably at least one polyol selected from polyether polyols, polyester polyols, polyacrylate polyols, and polycarbonate polyols.

[0027] Polyether polyols include, for example, polyalkylene glycols such as polyethylene glycol, polypropylene glycol, polypropylene glycol-ethylene glycol, polytetramethylene ether glycol, copolymer polyols of tetrahydrofuran and alkylene oxide, various modified products thereof, mixtures thereof, and the like.

[0028] Polyester polyols have two or more ester bonds and two or more hydroxyl groups in the molecule. Examples of polyester polyols include condensation reaction products of dicarboxylic acids and polyols. Examples of dicarboxylic acids include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and aliphatic dicarboxylic acids such as adipic acid, sebacic acid, and the like.

[0029] Polyacrylate polyols are copolymers of hydroxyl group-containing monomers and other olefinically unsaturated monomers, such as esters of (meth)acrylic acid, styrene, α-methylstyrene, vinyltoluene, vinyl esters, maleic acid monoalkyl esters and maleic acid dialkyl esters, fumaric acid monoalkyl esters and fumaric acid dialkyl esters, α-olefins, and other unsaturated oligomers and unsaturated polymers.

[0030] Polycarbonate polyols have two or more carbonate bonds and two or more hydroxyl groups in the molecule. Examples of polycarbonate polyols include condensation reaction products of polyols and carbonate compounds. Examples of carbonate compounds include dialkyl carbonates, diaryl carbonates, alkylene carbonates, and the like. Examples of polyols used as raw materials for polycarbonate polyols include diols such as hexanediol, butanediol, and triols such as 2,4-butanetriol. The polyol preferably has a number average molecular weight of 1,000 to 8,000, more preferably 1,000 to 5,000, in terms of excellent compatibility with isocyanates and the like described later. The number average molecular weight is the molecular weight converted to standard polystyrene by gel permeation chromatography (GPC).

[0031] - Polyisocyanate - Examples of the polyisocyanate include polyisocyanate monomers, polyisocyanate derivatives, and the like. Examples of the polyisocyanate monomer include polyisocyanates such as aromatic polyisocyanates, araliphatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.

[0032] Examples of the aromatic polyisocyanate include aromatic diisocyanates such as tolylene diisocyanate (2,4- or 2,6-tolylene diisocyanate or a mixture thereof) (TDI), phenylene diisocyanate (m-, p-phenylene diisocyanate or a mixture thereof), 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate (NDI), diphenylmethane diisocyanate (4,4'-, 2,4'- or 2,2'-diphenylmethane diisocyanate or a mixture thereof) (MDI), 4,4'-toluidine diisocyanate (TODI), and 4,4'-diphenyl ether diisocyanate.

[0033] Examples of the araliphatic polyisocyanate include araliphatic diisocyanates such as xylylene diisocyanate (1,3- or 1,4-xylylene diisocyanate or a mixture thereof) (XDI), tetramethylxylylene diisocyanate (1,3- or 1,4-tetramethylxylylene diisocyanate or a mixture thereof) (TMXDI), and 4,4'-diisocyanate-1,4-diethylbenzene.

[0034] Examples of aliphatic isocyanate compounds include hexamethylene diisocyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), lysine diisocyanate, norbornene diisocyanate methyl (NBDI), xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), and the like. Further, examples of alicyclic isocyanates include trans-cyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI), H6XDI (hydrogenated XDI), H12MDI (hydrogenated MDI), 4,4'-dicyclohexylmethane diisocyanate, and the like.

[0035] Examples of alicyclic polyisocyanates include 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, cyclohexane diisocyanate (1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate), 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate) (IPDI), methylene bis(cyclohexyl isocyanate) (4,4'-, 2,4'- or 2,2'-methylene bis(cyclohexyl isocyanate, their Trans,Trans-form, Trans,Cis-form, Cis,Cis-form, or a mixture thereof)) (H 12 MDI), methylcyclohexane diisocyanate (methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate), norbornane diisocyanate (various isomers or a mixture thereof) (NBDI), bis(isocyanatomethyl)cyclohexane (1,3- or 1,4-bis(isocyanatomethyl)cyclohexane or a mixture thereof) (H 6 XDI) and other alicyclic diisocyanates. These polyisocyanate monomers can be used alone or in combination of two or more.

[0036] Examples of polyisocyanate derivatives include multimers of the above-described polyisocyanate monomers (e.g., dimers, trimers (e.g., isocyanurate-modified products, iminooxadiazinedione-modified products), pentamers, heptamers, etc.), allophanate-modified products (e.g., allophanate-modified products formed by the reaction of the above-described polyisocyanate monomers with low-molecular-weight polyols described below, etc.), polyol-modified products (e.g., polyol-modified products (alcohol adducts) formed by the reaction of polyisocyanate monomers with low-molecular-weight polyols described below, etc.), biuret-modified products (e.g., biuret-modified products formed by the reaction of the above-described polyisocyanate monomers with water or amines, etc.), urea-modified products (e.g., urea-modified products formed by the reaction of the above-described polyisocyanate monomers with diamines, etc.), oxadiazinetrione-modified products (e.g., oxadiazinetriones formed by the reaction of the above-described polyisocyanate monomers with carbon dioxide gas, etc.), carbodiimide-modified products (e.g., carbodiimide-modified products formed by the decarboxylation condensation reaction of the above-described polyisocyanate monomers, etc.), uretdione-modified products, uretonimine-modified products, and the like. Furthermore, examples of polyisocyanate derivatives include polymethylene polyphenyl polyisocyanate (crude MDI, polymeric MDI), etc. These polyisocyanate derivatives can be used alone or in combination of two or more. Also, the above polyisocyanate compounds can be used alone or in combination of two or more. Furthermore, the polyisocyanate used in the present invention may be a blocked polyisocyanate.

[0037] In the mixture of polyol and polyisocyanate, the mixing ratio is preferably such that the molar ratio (NCO / OH) of the hydroxyl group (OH) contained in the polyol to the isocyanate group (NCO) contained in the polyisocyanate is 0.7 or more and 1.15 or less. This molar ratio (NCO / OH) is more preferably 0.85 or more and 1.10 or less in terms of preventing hydrolysis of the polyurethane. In practice, an amount equivalent to 3 to 4 times the appropriate molar ratio may be blended in consideration of the working environment and working errors. The content of the crosslinked polyurethane network is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 10% by mass or less with respect to the total mass of the water-soluble polymer.

[0038] The composition for forming the water-soluble polymer layer may contain components other than polyol, polyisocyanate, and organic solvent. Examples of other components include silane coupling agents, catalysts, antioxidants, and the like.

[0039] - Catalyst - The composition for forming the crosslinked polyurethane may contain a catalyst. Examples of the catalyst include tertiary amines such as N,N-dimethylaminoethanol, N,N-dimethyl-cyclohexamine-bis(2-dimethylaminoethyl)ether, N-ethylmorpholine, N,N,N’,N’,N”-pentamethyldiethylenetriamine, and 1-2(hydroxypropyl)imidazole, and metal catalysts such as tin, tin octoate, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin mercaptide, ferric acetylacetonate, lead octoate, dibutyltin dilinoleate, calcium carbonate, iron(III) acetylacetonate, etc. Preferred catalysts are dibutyltin dilinoleate and tin. The most preferred catalyst is dioctyltin dilaurate. The catalyst is preferably in the range of 0.05% by mass or more and 0.5% by mass or less in the polyol and blocked polyisocyanate.

[0040] - Antioxidant - The composition for forming the urethane coat layer may contain an antioxidant. The antioxidant is effective in improving the oxidation stability of the cured coating. Examples of the antioxidant include, but are not limited to, vitamin E, tris(3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, 2,2'-methylenebis(4-methyl-6-t-butylphenol), 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, butylhydroxytoluene, octadecyl 3,5-di-t-butyl-4-hydroxyhydrocinnamate, 4,4'-methylenebis(2,6-di-t-butylphenol), p,p'-dioctyldiphenylamine, 1,1,3-tris-(2-methyl-4-hydroxy-5-t-butylphenyl)butane. The antioxidant is preferably 0.01% by mass or more and 1% by mass or less in the polyol and the blocked polyisocyanate.

[0041] Examples of the coating method of the composition for forming the urethane coat layer include dipping, spray method, roll coating method, etc., in which any fixed part 20 is immersed in the composition for forming the urethane coat layer.

[0042] After applying the composition for forming the urethane coat layer, the urethane coat layer 14 can be formed by performing heat treatment at a temperature suitable for the reaction of the polyol and the polyisocyanate.

[0043] The thickness of the urethane coat layer 14 is not particularly limited, but the thickness formed by the above coating method is usually 1 μm or more and 20 μm or less.

[0044] (Other processes) -Surface modification treatment- Before forming the urethane coat layer 14, a surface modification treatment may be performed on at least the surface 11a of the fixed part 20 of the silicone tube 11. The surface modification treatment is preferably UV irradiation, excimer UV irradiation or plasma irradiation. By performing UV irradiation, excimer UV irradiation, or plasma irradiation, the methyl group, which is a substituent of the silicone rubber, is substituted with a hydroxyl group. When hydroxyl groups are generated on the surface 11a of at least the fixed portion 20 of the silicone tube 11, the surface 11a becomes hydrophilic, and the adhesiveness with the acrylic surgical tape is improved, so that the catheter 10 can be satisfactorily adhesively fixed.

[0045] As a method of performing UV irradiation, there is a method of irradiating using an irradiation device equipped with a known low-pressure mercury lamp. At this time, the atmosphere between the silicone tube 11 to be irradiated and the low-pressure mercury lamp may be filled with dry air or nitrogen gas, and low-pressure mercury UV may be irradiated.

[0046] The irradiation distance between the low-pressure mercury UV lamp and the surface 11a of the silicone tube 11 is not limited, and can be set to about 1 mm to 100 mm, for example. The illuminance of the low-pressure mercury UV lamp (unit: W / cm 2 ) is, for example, 1 mW / cm 2 to 100 W / cm 2 and the like, and 3 to 30 mW / cm 2 is preferable. The main wavelength of the low-pressure mercury lamp is preferably 254 nm. In addition, the main wavelengths of the excimer UV irradiation device include 126 nm, 146 nm, 172 nm, 222 nm, and 308 nm. Among them, 172 mm is preferable. In UV irradiation and excimer UV irradiation, by using the above wavelengths, the Si-CH 3 bond on the surface of the silicone rubber tube 11 and the bond with oxygen (O 2 ) in the air can be broken, and the generation of hydroxyl groups can be favorably performed in a short time.

[0047] The integrated light quantity of low-pressure mercury UV irradiation on the surface 11a of the silicone tube 11 (unit: J / m 2 ) is, for example, about 10 to 100,000 mJ / cm 2 and the like, and 25 to 10,000 mJ / cm 2is preferred, and 50 to 5000 mJ / cm 2 is more preferred. By being in the above range, the durability can be further improved.

[0048] In plasma irradiation, it is preferable to use oxygen as the process gas to be plasmaized. By using oxygen, the methyl groups of the silicone rubber can be favorably substituted with hydroxyl groups.

[0049] - Primer layer - Furthermore, after the surface modification treatment, a primer layer 15 made of a silane coupling agent may be provided on the surface 11a that has undergone the surface modification treatment, and a urethane coat layer 14 may be formed thereon. By having the primer layer 15, the adhesion between the silicone tube 11 and the urethane coat layer becomes good. The silane coupling agent is an organosilicon compound having one or more reactive groups that chemically bond to an organic material and two or more reactive groups that chemically bond to an inorganic material. Examples of the reactive group that chemically bonds to an organic material include a vinyl group, an epoxy group, a styryl group, a methacryl group, an acrylic group, an amino group, an isocyanate group, a ureido group, a mercapto group, etc. Among them, considering the bond with the isocyanate group remaining unused for producing polyurethane, a silane coupling agent having at least one of an amino group and an isocyanate group is preferred. Examples of the reactive group that chemically bonds to an inorganic material include alkoxy groups such as a methoxy group and an ethoxy group.

[0050] Specific silane coupling agents include, for example, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, hydrochloride of N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltrialkoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane and the like. Among these, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, hydrochloride of N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane are particularly preferred.

[0051] -Organic solvent- The organic solvent needs to be selected such that it does not react with the silane coupling agent and can be dissolved.

[0052] The thickness of the primer layer 15 is preferably 0.1 μm or more and 5.0 μm or less.

[0053] The primer layer 15 can be formed by applying a composition of a silane coupling agent and an organic solvent to the outer periphery of the catheter tube 11 and then crosslinking and drying it.

[0054] The catheter 10 produced by the method for manufacturing a catheter of the present invention has a urethane coat layer 14 on at least the fixing portion 20 and further on the entire silicone rubber tube 11. Therefore, it has good adhesiveness to a hydrophilic acrylic surgical tape, and the catheter 10 can be adhesively fixed well.

[0055] As long as it is a catheter having a silicone tube, it can also be applied to catheters having other configurations. The present invention can also be applied to, for example, a balloon catheter having a balloon at its tip.

Explanation of reference numerals

[0056] 10 Catheter 11 Silicone tube 11a Surface 12 Lumen 13 Side hole 14 Urethane coat layer 15 Primer layer 20 Fixing portion

Claims

1. A method for manufacturing a catheter having a silicone tube, comprising: a first step of forming the silicone tube; and a second step of forming a urethane coat layer on at least a fixing portion of the silicone tube.

2. The method for manufacturing a catheter according to claim 1, wherein a surface treatment is performed on a surface of an arbitrary fixing portion of the silicone tube before forming the urethane coat layer.

3. The method for manufacturing a catheter according to claim 2, wherein the surface treatment is UV irradiation, excimer UV irradiation, or plasma irradiation.

Images