Medical instrument, and method for producing medical instrument

Abstract

To provide a medical instrument with an antibacterial agent kneaded thereto, capable of exhibiting strong antibacterial action, and a method for producing the same.SOLUTION: A medical instrument includes a resin formation part including an antibacterial agent kneaded type silicone, wherein a surface roughness Ra of the resin formation part is 2.0 μm or more. Farther, a method for producing the medical instrument includes: a resin formation part forming process of forming a resin formation part including at least a silicone and an antibacterial agent; and a surface polishing process of polishing the whole or a part of a surface of the resin formation part.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to medical devices and methods for manufacturing medical devices. [Background technology]

[0002] Medical devices that have a resin molded part containing silicone, such as catheters inserted into blood vessels, digestive organs, urinary organs, etc., require antibacterial properties. To impart antibacterial properties, for example, an antibacterial agent is kneaded into a silicone catheter and introduced into the catheter. A silver-based antibacterial agent is used as the antibacterial agent (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 013911 Summary of the Invention [Problem to be solved by the invention]

[0004] Antibacterial agent-incorporated silicone catheters have low antibacterial properties, specifically, low antibacterial activity measured by the antibacterial test of JIS standard Z 2801, making it difficult to demonstrate sufficient antibacterial properties for practical use.

[0005] The present invention provides a medical device incorporating an antibacterial agent that can exhibit a strong antibacterial effect, and a method for producing the same. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention has the following aspects. [1] A medical device having a resin molded part containing antibacterial agent-incorporated silicone, wherein the surface roughness Ra of at least a part of the surface of the resin molded part is 2.0 μm or more. [2] The medical device according to [1], wherein the antibacterial agent is antibacterial metal microparticles that generate silver ions. [3] The medical device according to [1] or [2], wherein the medical device is a tube or a catheter. [4] A method for producing the medical device according to any one of [1] to [3], comprising: a resin molded part forming step of forming a resin molded part containing at least silicone and an antibacterial agent; and a surface polishing step of polishing at least a portion of the surface of the resin molded part. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an antibacterial agent-incorporated medical device having enhanced antibacterial properties and incorporating an antibacterial agent, and a method for producing the medical device. [Brief explanation of the drawings]

[0008] [Figure 1] 1 shows scanning electron microscope (SEM) photographs of the surfaces of the medical devices produced in the examples, with the left photograph being a comparative example and the right photograph being an example. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Medical equipment] A first aspect of the present invention is a medical device comprising a molded resin portion containing silicone, wherein an antibacterial agent is kneaded into the molded resin portion. Specific types of medical instruments include, for example, catheters, tubes (for example, dialysis tubes, drain tubes, etc.), and O-rings used in endoscopes.

[0010] The resin molded portion may be a base material that forms the entire medical device, or may be a base material that forms at least a part of the medical device.

[0011] The molded resin portion contains silicone, which is a known polymer having a main chain formed by siloxane bonds, and the side chains are appropriately selected according to the desired properties, and examples thereof include aliphatic alkyl groups such as methyl groups and ethyl groups, aryl groups such as phenyl groups, and halogen groups.

[0012] The type of silicone contained in the resin molded portion may be one type or two or more types. The silicone content relative to the total mass of the resin molded portion is, for example, preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. The upper limit of the content is not particularly limited, and may be, for example, 99.9% or less.

[0013] [catheter] As an example of the medical device of this embodiment, a catheter will be described below. A catheter is a medical device that has a tube portion that forms a conduit through which liquids and gases can flow, is inserted into the body, and is used for draining bodily fluids, injecting medicinal liquids, and the like. The specific dimensions and shape of the catheter are determined appropriately depending on the application. Examples of dimensions of a silicone resin balloon catheter include a total length of the tube portion of about 45 to 450 mm, an outer diameter of the tube portion of about 2 to 9 mm, an inner diameter of the duct of the tube portion of about 1 to 6 mm, and a longitudinal length of the balloon portion when inflated of about 8 to 25 mm.

[0014] An antibacterial agent is introduced into at least one, and preferably all, of the silicone-containing resin molded parts, such as the shaft, balloon, and funnel. The antibacterial agent is kneaded into the material of the resin molded part to form the resin molded part, so the resin molded part contains the antibacterial agent uniformly. For example, in a cylindrical catheter, the antibacterial agent is contained almost uniformly on the inner surface, the outer surface, and the area corresponding to the intermediate portion between them.

[0015] The silicone contained in the resin molded portion of the catheter is preferably silicone rubber. If the catheter is made of flexible silicone rubber, it can be easily inserted into the body and the discomfort caused when it is left in the body is reduced.

[0016] The surface roughness Ra of at least a portion of the surface of the molded resin portion is 2.0 μm or more. When the antibacterial agent is contained almost uniformly in the molded resin portion, the antibacterial agent is uniformly present near the surface (a region slightly buried inward from the surface). However, if the antibacterial agent is not exposed on the surface, it is not necessarily easy for the antibacterial agent to diffuse to the surface of the molded resin portion and elute to the outside to exhibit antibacterial properties. In this embodiment, the surface roughness Ra of the molded resin portion is 2.0 μm or more, so the antibacterial agent contained in the molded resin portion is easily exposed to the surface. When the antibacterial agent is easily exposed to the surface, the antibacterial effect of the antibacterial agent is more easily exhibited. That is, for example, in a medical device in which an antibacterial agent containing silver is kneaded, the antibacterial agent is exposed to the surface, which makes it easier to release silver ions and more easily exhibits antibacterial effect.

[0017] The proportion of the area having a surface roughness Ra of 2.0 μm or more in the entire surface area of ​​the resin molded part is preferably as large as possible, for example, 50% or more is preferable, 70% or more is more preferable, and 90% or more is even more preferable. This proportion may even be 100%. There is no particular upper limit to the surface roughness Ra of interest here, but the greater the surface roughness, the rougher the feel on the skin, so from the perspective of softening the feel on the skin, it is preferably 10 μm or less.

[0018] The surface roughness Ra of the surface of the resin molded portion can be measured as the arithmetic mean roughness Ra (unit: μm) measured in accordance with JIS B0601:1994.

[0019] Examples of antibacterial agents include antibacterial metal microparticles. Antibacterial metal microparticles may be microparticles that generate metal ions that have been known to have antibacterial properties, such as silver, silver salts, gold, zinc, copper, and cerium. These metals may be oxidized or may form compounds with other elements (e.g., silver compounds, copper compounds, silver salts (including silver complexes)), as long as they exhibit antibacterial properties. The antibacterial metal microparticles may be made of one type of metal, or may be made of any combination of two or more types. For example, they may be contained in the form of metallic silver. Antibacterial agents such as silver ion-supported zeolite and silver ion-fused glass can also be used.

[0020] The primary particle diameter of the antibacterial metal microparticles is preferably 0.1 to 100 μm, more preferably 0.1 to 50 μm, and even more preferably 0.1 to 30 μm. Within this range, metal ions do not leach out of the resin molded part only temporarily, but can continue to leach out continuously. For example, silver ion-supported zeolite has a particle diameter of about 2 μm, and antibacterial agents such as silver ion fused glass have a particle diameter of about 40 μm, and these can be used preferably. The primary particle diameter of the antibacterial metal microparticles is the average value obtained by measuring the major axes of 10 or more antibacterial metal microparticles contained in the resin molded part using an electron microscope (SEM or TEM).

[0021] Examples of silver salts include silver acetate, silver acetylacetonate, silver azide, silver acetylide, silver arsenate, silver benzoate, silver hydrogen fluoride, silver bromate, silver bromide, silver carbonate, silver chloride, silver chlorate, silver chromate, silver citrate, silver cyanate, silver cyanide, (cis,cis-1,5-cyclooctadiene)-1,1,1,5,5,5-hexafluoroacetylacetonate, silver diethyldithiocarbamate, silver fluoride(I), silver fluoride(II), silver 7,7-dimethyl-1,1,1,2,2,3,3-heptafluoro-4,6-octanedionate, silver hexafluoroantimonate, silver hexafluoroarsenate, silver hexafluorophosphate, silver iodate, silver iodide Examples of silver include silver, silver isothiocyanate, silver potassium cyanide, silver lactate, silver molybdate, silver nitrate, silver nitrite, silver (I) oxide, silver (II) oxide, silver oxalate, silver perchlorate, silver perfluorobutyrate, silver perfluoropropionate, silver permanganate, silver perrhenate, silver phosphate, silver picrate monohydrate, silver propionate, silver selenate, silver selenide, silver selenite, silver sulfadiazine, silver sulfate, silver sulfide, silver sulfite, silver telluride, silver tetrafluoroborate, silver tetraiodocurate, silver tetratungstate, silver thiocyanate, silver p-toluenesulfonate, silver trifluoromethanesulfonate, silver trifluoroacetate, and silver vanadate. Examples of silver complexes include histidine silver complex, methionine silver complex, cysteine ​​silver complex, aspartic acid silver complex, pyrrolidone carboxylic acid silver complex, oxotetrahydrofuran carboxylic acid silver complex, and imidazole silver complex.

[0022] The content of antibacterial metal microparticles contained in the resin molded part is preferably 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the content of the compounds constituting the resin molded part (i.e., the total mass of the resin molded part). When the content is equal to or greater than the lower limit of the above range, the amount of antibacterial agent released from the resin molded portion increases, thereby enhancing the antibacterial properties. When the content is equal to or less than the upper limit of the above range, poor appearance due to discoloration of metals that may be contained in the antibacterial agent can be made less noticeable.

[0023] In addition to the resin molded portion into which the antibacterial agent is kneaded, the catheter may also include, for example, an intermediate layer formed on the surface of the resin molded portion, or a hydrophilic layer formed on the surface of the intermediate layer. When these layers are included, the surface roughness Ra of the intermediate layer and the hydrophilic layer is not particularly limited, and may be 2.0 μm or more or less than 2.0 μm. Generally, the intermediate layer and hydrophilic layer are more permeable to antibacterial agents than the molded resin part (resin substrate) containing silicone, so the surface roughness Ra of the intermediate layer and hydrophilic layer does not have much effect on antibacterial properties. In the catheter of this embodiment, the intermediate layer formed on the surface of the resin molded portion and the hydrophilic layer formed on the surface of the intermediate layer can be formed after polishing the surface of the resin molded portion to a surface roughness Ra of 2.0 or more, as described below.

[0024] The intermediate layer is a layer that bonds the molded resin portion and the hydrophilic layer together. The thickness of the intermediate layer can be, for example, about 0.05 μm to 5 μm. When the amount is within the above range, the adhesive strength between the resin molded portion and the hydrophilic layer can be improved, and the durability of the hydrophilic layer can be further improved.

[0025] The intermediate layer preferably contains a compound having one or more active groups selected from an isocyanate group, a vinyl group, an epoxy group, and an amino group. The inclusion of these compounds improves the adhesion between the resin molded part and the hydrophilic layer, thereby further improving the durability of the hydrophilic layer in the body. At least a portion of the active groups of the compound contained in the intermediate layer is bonded to the surface of the resin molded part or the surface of the hydrophilic layer that is bonded to the intermediate layer.

[0026] The compound having an isocyanate group (isocyanate compound) is an organic compound having one or more isocyanate groups in the molecule. From the viewpoint of further improving the adhesiveness and durability, the isocyanate compound preferably has two or more of the active groups, including the isocyanate group, in the molecule. Furthermore, the isocyanate compound is preferably an isocyanate-based silane coupling agent having a functional group (-Si-O-) in the molecule that functions as a silane coupling agent. Specific examples of the isocyanate compound include diisocyanates such as diphenylmethane diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, xylene diisocyanate, naphthalene diisocyanate, triphenylmethane diisocyanate, etc. Any of the hydrogen atoms of these isocyanate compounds may be substituted with a functional group that functions as a silane coupling agent.

[0027] The intermediate layer may contain one or more types of isocyanate compounds. The content of the isocyanate compounds relative to the total mass of the intermediate layer varies depending on the type of isocyanate compound, but is preferably, for example, 50 to 100 mass%. This preferred range can further improve the above-mentioned adhesion and durability.

[0028] The vinyl group-containing compound (vinyl compound) is an organic compound having one or more vinyl groups in the molecule. From the viewpoint of further improving the adhesiveness and durability, the vinyl compound preferably has two or more of the active groups, including the vinyl group, in the molecule. Furthermore, the vinyl compound is preferably a vinyl-based silane coupling agent having a functional group (-Si-O-) in the molecule that functions as a silane coupling agent. Specific examples of the vinyl compound include epoxy group-containing vinyl compounds such as methyl glycidyl methacrylate, methyl glycidyl acrylate, allyl glycidyl ether, allylphenol glycidyl ether, glycidyl methacrylate, etc. Any of the hydrogen atoms in these vinyl compounds may be substituted with a functional group that functions as a silane coupling agent.

[0029] The intermediate layer may contain one type of vinyl compound or two or more types. The content of the vinyl compound relative to the total mass of the intermediate layer varies depending on the type of vinyl compound, but is preferably, for example, 50 to 100 mass%. This preferred range can further improve the above-mentioned adhesiveness and durability.

[0030] The compound having an epoxy group (epoxide) is an organic compound having one or more epoxy groups in the molecule. From the viewpoint of further improving the adhesiveness and durability, the epoxide preferably has two or more of the active groups including the epoxy group in the molecule. Specific examples of epoxides include the above-mentioned epoxy group-containing vinyl compounds, as well as glycidyl propionate, diglycidyl adipate, diglycidyl ether of 1,1-dimethylol-3-cyclohexane, triglycidyl ether of glycerol, diglycidyl ether of 2,5-bis(hydroxymethyl)tetrahydrofuran, butyl glycidyl ether, phenyl glycidyl ether, diglycidyl ether of bisphenol A, diglycidyl ether of resorcinol, and triglycidyl ether of phloroglucinol.

[0031] The intermediate layer may contain one type of epoxide or two or more types. The content of epoxide relative to the total mass of the intermediate layer 3 varies depending on the type of epoxide, but is preferably, for example, 50 to 100 mass %. When the content is in this preferred range, the above-mentioned adhesiveness and durability can be further improved.

[0032] The compound having an amino group has one or more amino groups in the molecule, and preferably has two or more of the active groups, including the amino group, in the molecule, from the viewpoint of further improving the adhesiveness and durability. Specific examples of the compound having an amino group include 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 2,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane, 1,6-hexamethylenediamine, and the like. Examples of diamines include 1,8-octamethylenediamine, azelaic acid dihydrazide, sebacic acid dihydrazide, 2,4'-diamino-3-methyl-stearylphenyl ether, 2,4'-diamino-1-octyloxybenzene, 2,2-bis(4-(4-aminophenoxy)phenyl)octane, bis(4-(4-aminobenzoyloxy)benzoic acid)octane, diaminosiloxane, and 1,3-di(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane. Furthermore, it is also preferable that the compound having an amino group is an amino-based silane coupling agent having a functional group (-Si-O-) in the molecule that functions as a silane coupling agent.

[0033] The intermediate layer may contain one or more types of compounds having an amino group. The content of the compounds having an amino group relative to the total mass of the intermediate layer varies depending on the type of compound, but is preferably, for example, 50 to 100 mass%. This preferred range can further improve the adhesiveness and durability.

[0034] The hydrophilic layer is a hydrophilic coating layer that provides lubricity to the outermost surface of the medical device. The thickness of the hydrophilic layer is, for example, about 0.1 μm to 15 μm, preferably 0.2 μm to 10 μm, and more preferably 0.3 μm to 5 μm. Within the above preferred range, the effect of reducing friction on the surface of the medical device is enhanced, the adhesion of the hydrophilic layer to the intermediate layer is improved, and the durability of the hydrophilic layer in the body can be further improved.

[0035] The hydrophilic layer preferably contains a water-soluble polymer. Examples of the water-soluble polymer include -OH, -CONH2, -COOH, -NH2, and -COO - , -SO2 - , -NR3 + (where R is any organic group) and other linear polymer compounds having hydrophilic groups. Specifically, for example, starch-based polymers such as carboxymethyl starch and dialdehyde starch; cellulose-based polymers such as carboxymethyl cellulose (CMC), methyl cellulose (MC), hydroxyethyl cellulose (HEC), and hydroxypropyl cellulose (HPC); wood-based polymers such as tannin and lignin; polysaccharide-based polymers such as alginic acid, gum arabic, guar gum, tragacanth gum, and tamarind seeds; protein-based polymers such as gelatin, casein, glue, and collagen; PVA-based polymers such as polyvinyl alcohol; polyethylene oxide and polyethylene glycol Examples of suitable polymers include polyethylene oxide polymers such as polyethylene glycol; acrylic acid polymers such as sodium polyacrylate; maleic anhydride polymers such as methyl vinyl ether-maleic anhydride copolymer; phthalic acid polymers such as polyhydroxyethyl phthalate ester; water-soluble polyesters such as polydimethylol propionate ester; ketone aldehyde resins such as methyl isopropyl ketone formaldehyde; acrylamide resins such as polyacrylamide; polyvinylpyrrolidone (PVP); polyamines such as polyethyleneimine; polystyrene sulfonate; and water-soluble nylon.

[0036] The hydrophilic layer may contain one or more types of water-soluble polymer. The content of the water-soluble polymer relative to the total mass of the hydrophilic layer varies depending on the type of water-soluble polymer, but is preferably, for example, 70 to 100% by mass. Within this preferred range, the lubricity and durability can be further improved.

[0037] When an intermediate layer is provided, the surface of the molded resin part is modified to produce silanol groups (Si-OH), and a silane coupling agent is used to bond the interface by reacting the silanol groups of the molded resin part with the silanol groups of the silane coupling agent. For the hydrophilic layer, polyol, polyisocyanate, and polyvinylpyrrolidone (PVP) are used, and some of the isocyanate groups are reacted with the amino groups of the silane coupling agent to bond the interface, and polyurethane (PU) is generated from the reaction of the remaining isocyanate groups with polyol, and a hydrophilic layer consisting of a mixture of PVP and PU can also be formed. On the other hand, if no intermediate layer is provided, the surface of the resin molded part can be modified to produce silanol groups (Si-OH), and a hydrophilic layer can be formed using a silane coupling agent, polyol, polyisocyanate, and PVP.

[0038] The silane coupling agent is an organosilicon compound having two or more different reactive groups in the molecule. Examples of the reactive groups include vinyl groups, epoxy groups, styryl groups, methacrylic groups, acrylic groups, amino groups, isocyanurate groups, ureido groups, mercapto groups, and isocyanate groups. Among them, silane coupling agents having isocyanurate groups are preferred because they significantly improve lubricity and durability through excimer UV treatment. Specific examples of the silane coupling agent include 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-dimethylbutylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, tris-(trimethoxysilylpropyl)isocyanurate, 3-ureidopropyltrialkoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, etc. Among these, tris-(trimethoxysilylpropyl)isocyanurate having an isocyanurate group is particularly preferred.

[0039] A silane coupling agent may be blended into the resin molded portion. In this case, the type of silane coupling agent contained in the resin molded portion may be one type, or two or more types. The content of the silane coupling agent relative to the total mass of the resin molded portion varies depending on the type of silane coupling agent, but is preferably, for example, 0.1 to 30 mass%. Within this preferred range, the lubricity and durability described above can be further improved.

[0040] The silicone contained in the resin molded portion constituting the catheter is preferably silicone rubber. If the catheter is made of flexible silicone rubber, it can be easily inserted into the body and the discomfort caused when the catheter is left in the body is reduced.

[0041] [Medical device manufacturing method] A second aspect of the present invention is a method for producing a medical device, which comprises at least the following steps: According to this aspect, the medical device of the first aspect can be easily produced. An example embodiment of this aspect includes at least a resin molded portion forming step and a surface polishing step.

[0042] The resin molded portion forming step is a step of forming a resin molded portion containing at least silicone and an antibacterial agent. The formed resin molded portion may be a substrate that forms the entire medical device, or may be a substrate that forms at least a part of the medical device. As a method for forming the resin molded portion, a known method may be applied depending on the material of the base material. The resin molded part may be a resin member formed by a known resin molding method such as extrusion molding, injection molding, etc. using a resin composition containing silicone, an antibacterial agent, and the optional silane coupling agent as a raw material. Alternatively, the resin molded part may be a resin layer formed by applying and curing the resin composition to the surface of a substrate made of glass, metal, another resin molded part, etc. The resin composition may contain other optional components as needed, such as a solvent, a known crosslinking agent that crosslinks and hardens the silicone, and a curing agent such as a catalyst.

[0043] The effect of this embodiment is achieved by polishing the surface of the molded resin part containing antibacterial agent-infused silicone, and therefore the greatest antibacterial effect can be achieved for the entire medical device when the entire surface of the molded resin part containing antibacterial agent-infused silicone is polished. However, if it is desired to obtain a localized antibacterial effect or to adjust the antibacterial effect, it is also possible to polish only part of the surface of the molded resin part containing antibacterial agent-infused silicone.

[0044] It is desirable to use sandpaper for surface polishing. The roughness (grain size) of the sandpaper is not particularly limited, but is preferably within the range of #400 to #1000. If it is within this range, when the resin forming portion is surface polished, the surface roughness Ra of the resin forming portion can easily be 2.0 or more. [Example]

[0045] A silicone rubber composition was prepared by kneading an appropriate amount of a commercially available antibacterial agent into a commercially available addition-curing millable silicone rubber (such as that described in JP 2023-023431 A), and several press sheets were prepared using conventional methods and used in the following tests.

[0046] [Example 1] The surface of the silicone press sheet that corresponds to the resin molding part was polished using sandpaper #400. In accordance with JIS B0601:2013, the polished surface was observed with a laser microscope and the surface roughness was measured, and the surface roughness Ra was found to be 2.0 μm or more. [Example 2] The surface of the silicone press sheet that corresponds to the resin molding part was polished using sandpaper #1000. In accordance with JIS B0601:2013, the polished surface was observed with a laser microscope and the surface roughness was measured, and the surface roughness Ra was found to be 2.0 μm or more.

[0047] [Comparative Example 1] Except for not performing surface polishing, the same operations as in Examples 1 and 2 were performed. The surface was observed with a laser microscope in accordance with JIS B0601:2013, and the surface roughness was measured. As a result, the surface roughness Ra was less than 2.0 μm.

[0048] [Antibacterial evaluation test] Test specimens were prepared from surface-polished silicone press sheets in accordance with JIS standard Z 2801, and antibacterial tests were conducted. For Comparative Example 1, a test piece was prepared from a pressed silicone sheet without surface polishing in accordance with JIS standard Z 2801, and an antibacterial test was carried out. The results are shown in Table 1.

[0049] [Table 1]

[0050] In Comparative Example 1, the antibacterial activity value measured according to JIS standard Z 2801 was as low as 0.6, and sufficient antibacterial properties could not be exhibited. In Examples 1 and 2, the antibacterial activity value measured according to JIS standard Z 2801 was as high as 6.1, and sufficient antibacterial properties were exhibited. The above results show that Examples 1 and 2, which were subjected to surface polishing and had a surface roughness Ra of 2.0 μm or more, have a sufficient antibacterial effect. On the other hand, Comparative Example 1, in which the surface was not polished and the surface roughness Ra was less than 2.0 μm, was unable to exhibit a sufficient antibacterial effect.

[0051] <Surface observation> To confirm the difference in surface condition depending on whether or not the surface was polished with sandpaper, SEM images were taken of the surface of the press sheet after polishing in Example 1 and the surface of the unpolished press sheet in Comparative Example 1. The results are shown in Figure 1. From the results in Figure 1, numerous irregularities resulting from antibacterial agent particles were observed as white dots on the surface of the resin molded part where the surface roughness Ra was increased to 2.0 μm or more by surface polishing. On the other hand, the surface of the resin molded part that was not polished was smooth, and it was found that the antibacterial agent particles were less exposed. From these results, it was found that when the surface of the resin molded part is polished to a surface roughness Ra of 2.0 μm or more, the antibacterial agent is more likely to be exposed on the surface.

Claims

1. A medical device comprising a resin molded part containing antibacterial agent-incorporated silicone, wherein at least a portion of the surface of the resin molded part has a surface roughness Ra of 2.0 μm or more.

2. The medical device according to claim 1 , wherein the antibacterial agent is antibacterial metal microparticles that generate silver ions.

3. The medical device according to claim 1 or 2, wherein the medical device is a tube or a catheter.

4. 2. A method for manufacturing the medical device according to claim 1, comprising: a resin molded portion forming step of forming a resin molded portion containing at least silicone and an antibacterial agent; and a surface polishing step of polishing at least a portion of the surface of the resin molded portion.

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