Cover for endoscope

Abstract

Provided is a cover for an endoscope, the cover having, in particular, an anti-fogging property or an anti-fouling property, sufficient strength and elastic force for pushing away biological tissue at the distal end. The endoscope cover (1) is provided with a hydrogel main body part (5) and a second tip part (7), and the main body part (5) is provided with: an exterior part (2) having a substantially cylindrical shape; a disk section (3), the entire circumference of which is in contact with the inner surface of the exterior section (2); and a first tip portion (4) connected to the insertion-side end portion of the exterior portion (2), and a second tip portion (7) including an annular member (6) connected to the insertion-side end portion of the first tip portion (4).

Description

Technical Field

[0001] The present invention relates to a cover for an endoscope. Background Art

[0002] The endoscope is formed with a plurality of through holes penetrating in the longitudinal direction, and a camera lens or an illumination lens for ensuring a field of view is disposed in these through holes.

[0003] In a surgery or an examination using an endoscope, for the purpose of confirming the optimal distance from the distal end portion of the endoscope to the biological tissue and ensuring the field of view, a transparent endoscope cover made of ABS, polycarbonate, vinyl chloride, or the like is attached to the distal end portion of the endoscope. In recent years, for the purpose of preventing damage to biological tissue, a transparent endoscope cover made of silicone rubber or the like is also attached to the distal end portion of the endoscope.

[0004] However, in the above-described endoscope cover, for the purpose of confirming the optimal distance from the distal end portion of the endoscope to the biological tissue and ensuring the field of view, the portion of the camera lens or the illumination lens is not covered when attached to the distal end portion of the endoscope. Therefore, in an examination or a surgery using the endoscope with the above-described endoscope cover attached, there is a technical problem that the field of view becomes unclear due to attachment of body fluid or oil.

[0005] Therefore, for the purpose of providing stain resistance to the camera lens or the illumination lens, an endoscope cover that can cover even the lens portion is formed. In addition, an endoscope cover that has been subjected to an antifogging treatment (see Patent Document 1 or Patent Document 2), an endoscope cover having a hydrophilic coating (see Patent Document 3 or Patent Document 4), and the like are known.

[0006] In addition, a technique of providing a liquid spraying mechanism in the endoscope to clean the lens portion is also known (see Patent Document 5).

[0007] Prior Art Documents

[0008] Patent Documents

[0009] Patent Document 1: Japanese Patent Laid-Open No. 11-047081

[0010] Patent Document 2: Japanese Patent Laid-Open No. 2004-267583

[0011] Patent Document 3: Japanese Patent Laid-Open No. 2007-151685

[0012] Patent Document 4: Japanese Patent Laid-Open No. 2009-213631

[0013] Patent Document 5: Japanese Patent Laid-Open No. 2009-240596 Summary of the Invention

[0014] Technical problem to be solved by the invention

[0015] However, since the endoscope cover or lens is formed of a material with high lipophilicity, its affinity with body fluids or oils is extremely high. During long-term use, the attached body fluids or oils cannot be completely removed, and the effects of the antifogging and antifouling techniques described in Patent Documents 1 to 5 cannot be considered sufficient.

[0016] In addition, in the case of significant atomization or contamination, the operation of the surgery or examination must be temporarily interrupted, the endoscope must be removed to remove the contamination, and then reinserted. The prolongation of the operation or the burden on the patient caused by the reinsertion becomes a problem. Therefore, it is necessary to develop an endoscope cover with excellent stain resistance.

[0017] Therefore, the inventors of the present application have developed an endoscope cover made entirely of hydrogel, which has excellent antifogging and antifouling properties.

[0018] However, since the vicinity of the tip of the endoscope cover also has a function of pushing away biological tissues, in addition to antifogging or antifouling properties, flexibility and strength that do not damage biological tissues are also required.

[0019] In addition, the inventors of the present application have confirmed that forming the endoscope cover only of hydrogel significantly improves the antifogging or antifouling properties by having excellent hydrophilicity as a whole. However, the high flexibility peculiar to hydrogel is not the best for pushing away biological tissues, and there is room for improvement in particular in the tip portion of the endoscope cover for the function of pushing away biological tissues.

[0020] Therefore, the present invention is made to solve the above technical problems, and its object is to provide an endoscope cover that has sufficient strength and elasticity for pushing away biological tissues not only in terms of antifogging or antifouling properties, but especially at the tip portion.

[0021] Means for solving the technical problem

[0022] The gist of the endoscope cover according to one technical solution lies in having a main body portion made of hydrogel and a second tip portion. The main body portion has: an outer package portion having a substantially cylindrical shape; a disk portion whose entire circumference is in contact with the inner side surface of the outer package portion; and a first tip portion connected to the insertion-side end portion of the outer package portion. The second tip portion is connected to the insertion-side end portion of the first tip portion and includes an annular member.

[0023] Advantages of the invention

[0024] According to the present invention, it is possible to provide an endoscope cover that has sufficient strength and elasticity for pushing away biological tissues not only in terms of antifogging or antifouling properties, but especially at the tip portion. Description of the drawings

[0025] Figure 1 This is an example of a cross-sectional view and a top view of the endoscope cover 1 according to an embodiment.

[0026] Figure 2 This is a diagram showing an example of the state in which the endoscope cover according to an embodiment is installed.

[0027] Symbol Explanation

[0028] 1: Endoscope cover;

[0029] 2: Exterior part;

[0030] 3: Disk part;

[0031] 4: First tip part;

[0032] 5: Main body part;

[0033] 6: Annular member;

[0034] 7: Second tip part;

[0035] 8: Tip part;

[0036] 9: Forceps opening;

[0037] 10: Water supply port;

[0038] a: Length of the tip part;

[0039] b: Length of the exterior part;

[0040] c: Thickness of the exterior part;

[0041] d: Thickness of the disk part;

[0042] e: Inner diameter of the exterior part;

[0043] e2: Inner diameter of the annular member;

[0044] f: Outer diameter of the exterior part;

[0045] f2: Outer diameter of the annular member;

[0046] g: Thickness of the tip part. Detailed Embodiment

[0047] Hereinafter, while appropriately referring to the attached Figure 1The embodiments will be described in detail below. However, sometimes the detailed descriptions may be overly omitted. For example, sometimes the detailed descriptions of well-known matters or the repeated descriptions of substantially the same structures are omitted. This is to avoid making the following descriptions unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the inventor provides the accompanying drawings and the following descriptions to enable those skilled in the art to fully understand the present invention, but this does not mean that the subject matter of the technical solution is limited based on these.

[0048] In addition, in the descriptions of the following drawings, the same or similar reference numerals are assigned to the same or similar parts. However, it should be noted that the drawings are schematic, and the ratios of various dimensions and the like may sometimes be different from the actual ones. Therefore, specific dimensions and the like must be determined with reference to the following descriptions. Additionally, there may be parts where the relationships or ratios of the dimensions to each other are different between the drawings.

[0049] <First Embodiment>

[0050] Refer to Figures 1 to 2 , and the endoscope cover 1 according to the first embodiment of the present invention will be described. Figure 1 is an example of a cross-sectional view and a top view of the endoscope cover 1 according to the present embodiment, Figure 2 is a view showing an example of the state in which the endoscope cover according to one embodiment is installed.

[0051] The endoscope cover 1 according to the present embodiment is an endoscope cover made of hydrogel. As Figure 1 shown, it has a main body portion 5 and a second tip portion 7.

[0052] As Figure 1 shown, the main body portion 5 has an outer covering portion 2, a disk portion 3, and a first tip portion 4.

[0053] The outer covering portion 2 has a substantially cylindrical shape and is in contact with the outer side surface of the endoscope on the inner side surface, and is configured to fix the endoscope cover 1 to the endoscope.

[0054] The length b of the outer covering portion 2 is not particularly limited as long as it is a length sufficient to fix the endoscope cover 1 to the endoscope, and is preferably 5 to 20 mm, more preferably 10 to 15 mm. In addition, the thickness c of the outer covering portion 2 is preferably 0.1 to 1.0 mm, more preferably 0.3 to 0.5 mm. Moreover, the inner diameter e of the outer covering portion 2 can be appropriately designed according to the endoscope to be used.

[0055] The disk portion 3 has a disk shape and is provided in contact with the entire circumference of the inner side surface of the outer covering portion 2. Except for having a forceps opening 9 that serves as an entrance and exit for the forceps and a water supply port 10 that serves as an outlet for the cleaning water, it also covers the insertion-side end portion of the endoscope, and is particularly configured to prevent contamination of the camera lens.

[0056] The disk portion 3 is formed into a substantially flat surface. The thickness d of the disk portion 3 is preferably 0.01 to 1.0 mm, more preferably 0.05 to 0.7 mm, and most preferably 0.1 to 0.5 mm. When the thickness d of the disk portion 3 is greater than 1.0 mm, it will have an adverse effect on the field of view obtained through the camera lens. In addition, when the thickness d of the disk portion 3 is less than 0.01 mm, the strength of the disk portion 3 becomes low, and breakage may occur during use, so it is not preferred.

[0057] The first tip portion 4 has a cylindrical shape formed with dimensions substantially the same as the inner diameter e and the outer diameter f of the outer package portion 2, and is provided connected to the insertion-side end portion of the outer package portion 2 so as to form a part of the tip portion 8.

[0058] In addition, the second tip portion 7 also has a cylindrical shape formed with dimensions substantially the same as the inner diameter e and the outer diameter f of the outer package portion 2, and is provided connected to the insertion-side end portion of the first tip portion 4. Here, the second tip portion 7 includes an annular portion 6.

[0059] The length a of the tip portion 8 formed by the first tip portion 4 and the second tip portion 7 is not particularly limited as long as it is a length that can ensure the optimal distance and field of view, and is preferably 1 to 10 mm, more preferably 2 to 5 mm. Here, when the length a of the tip portion 8 is greater than 10 mm, the entry of the tip portion with respect to the camera lens becomes larger and the field of view becomes narrower, so it is not preferred.

[0060] In addition, the thickness g of the tip portion 8 is preferably 0.1 to 1.0 mm, more preferably 0.3 to 0.5 mm.

[0061] In addition, it is preferred that the 30% deformation compression flexural strength of the annular portion 6 is stronger than the 30% deformation compression flexural strength of the main body portion 5.

[0062] According to the above structure, by increasing the strength of the tip portion 8 (the second tip portion 7) including the annular portion 6 compared to the strength of the main body portion 5, it is possible to impart an appropriate strength to the tip portion 8 of the hydrogel endoscopic cover 1 according to the present embodiment for pushing away biological tissues.

[0063] In addition, the 30% deformation compression flexural strength of the annular portion 6 is preferably 1.0 N to 2.0 N.

[0064] When the 30% deformation compression flexural strength of the annular portion 6 is less than 1.0 N, the function of pushing away biological tissues cannot be imparted to the tip portion 8 of the hydrogel endoscopic cover 1 according to the present embodiment. When the 30% deformation compression flexural strength of the annular portion 6 is greater than 2.0 N, the hydrogel endoscopic cover 1 according to the present embodiment may cause damage to the tip portion of the main body during use, so it is not preferred.

[0065] As the method for forming the second tip portion 7 according to the present embodiment, after disposing the previously formed annular member 6 at a predetermined position of the molding die for forming the endoscope cover 1, a polymerizable composition for forming the main body portion 5 is injected to obtain the first mode for copolymerization reaction.

[0066] Regarding the shape of the annular member 6 in the first mode, the inner diameter e2 is made larger than the inner diameter e of the outer covering portion 2, and the outer diameter f2 is made smaller than the outer diameter f of the outer covering portion 2. Thus, in the process of injecting the polymerizable composition for forming the main body portion 5 for copolymerization reaction, the annular member 6 is covered by the endoscope cover 1.

[0067] By having the above structure, the tip portion 8 (the second tip portion 7) including the annular member 6 is given stain resistance, which is therefore preferable.

[0068] In the process of forming the endoscope cover 1 according to the present embodiment, before placing the annular member 6 on the jig for forming the main body portion 5, by performing pretreatment such as plasma irradiation or corona discharge, the affinity between the annular member 6 and the main body portion 5 can be improved in the copolymerization reaction.

[0069] As the method for forming the second tip portion 7 according to the present embodiment, after injecting a predetermined amount of polymerizable composition into the end portion on the insertion side of the molding die for forming the endoscope cover 1 to form the annular member 6 for polymerization reaction, the polymerizable composition for forming the main body portion 5 is continuously injected to obtain the second mode for further copolymerization reaction.

[0070] In the second mode, the inner diameter e2 and the outer diameter f2 of the annular member 6 are respectively the same values as the inner diameter e and the outer diameter f of the outer covering portion 2.

[0071] In the first mode, as the material of the annular member 6 for forming the endoscope cover 1 according to the present embodiment, thermoplastic elastomers selected from polystyrene-based, olefin-based, PVC-based, polyurethane-based, polyester-based, polyamide-based, EVA-based, or acrylic-based, etc., and thermosetting elastomers selected from vulcanized rubber and resin-based elastomers, etc. can be cited.

[0072] In addition, in the second mode, as the material of the annular member 6 for forming the endoscope cover 1 according to the present embodiment, a crosslinked hydrophilic polymer (hydrogel) can be cited.

[0073] In addition, as the molding method of the annular member 6, the molding method of the material used can be appropriately selected from known methods such as injection molding, casting molding, or cutting molding, and processed into a desired shape.

[0074] When a crosslinked hydrophilic polymer (hydrogel) is selected as the material of the annular member 6, the polymerizable composition for forming the annular member 6 may have the same or different components as the polymerizable composition for forming the main body portion 5 described later. However, importantly, especially in the same case, the amount ratio of the crosslinkable monomer compounded with the polymerizable composition for forming the annular member 6 is made larger than the amount of the crosslinkable monomer compounded with the polymerizable composition for forming the main body portion 5.

[0075] The specific compounding amounts will be described later. However, by increasing the amount of the crosslinkable monomer in this way, the crosslinking density of the annular member 6 is made higher than that of the main body portion 5, thereby improving the strength. Therefore, when the annular member 6 (the second tip portion 7) and the main body portion 5 are combined to form the endoscope cover 1 according to the present embodiment, preferable strength can be imparted to the tip portion 8.

[0076] The strength of the annular member 6 of the present invention is described in detail in the examples. However, in the present invention, by evaluating the 30% deformation compression flexural strength (N) when the annular member 6 is loaded, the 30% deformation compression flexural strength is preferably 1.0 to 2.0 (N), more preferably 1.1 to 1.9 (N), and most preferably 1.2 to 1.8 (N).

[0077] When the 30% deformation compression flexural strength of the annular portion 6 is less than 1.0 (N), the strength for pushing away the biological tissue is insufficient. When the 30% deformation compression flexural strength of the annular portion 6 is greater than 2.0 N, the hydrogel endoscope cover 1 according to the present embodiment may cause damage to the tip portion of the main body during use, and thus is not preferable.

[0078] In the endoscope cover 1 according to the present embodiment, the main body portion 5 is made of a hydrogel. Examples of the hydrogel include a hydrogel formed by using only hydrophilic monomers, a hydrogel formed by adding hydrophobic monomers or crosslinkable monomers or both to hydrophilic monomers, and the like.

[0079] The hydrophilic monomers contribute to the water content rate of the hydrogel, and the hydrophobic monomers contribute to the adjustment of the water content rate and the swelling rate of the hydrogel, thereby affecting the wettability or softness of the obtained endoscope cover 1.

[0080] In addition, the crosslinkable monomer can control the density of the polymer chains of the hydrogel according to its content, and can impart mechanical strength, shape stability, or solvent resistance to the hydrogel.

[0081] The water content rate of the hydrogel (water content rate (weight %) = [(W - D) / W] × 100 (W: water-containing weight, D: dry weight)) is not particularly limited, but can be set to, for example, 20 to 70% by weight. In addition, the water content rate can be appropriately selected as needed.

[0082] The hydrophilic monomer preferably has one or more hydrophilic groups in the molecule. Examples thereof include 2-hydroxyethyl (meth)acrylate, 2-hydroxymethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, glycerol (meth)acrylate, acrylamide, N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, N-vinyl pyrrolidone, diacetone acrylamide, N-vinyl acetamide, (meth)acrylic acid, (meth)acryloyloxyethyl succinic acid, itaconic acid, methacrylamidopropyltrimethylammonium chloride, and 2,3-dihydroxypropyl (meth)acrylate. At least one of these monomers or a combination of two or more thereof can be used.

[0083] Among the hydrophilic monomers described above, 2-hydroxyethyl (meth)acrylate, N,N-dimethyl (meth)acrylamide, and N-vinyl pyrrolidone are preferably used in the present invention from the viewpoint of handleability.

[0084] The blending ratio of the hydrophilic monomer is not particularly limited, but is preferably 50% by weight or more of the total polymer components from the viewpoint of affecting the moisture content of the resulting endoscope cover 1. If the blending ratio of the hydrophilic monomer is less than 50% by weight, an endoscope cover 1 having a sufficient moisture content cannot be obtained, and thus the antifouling and anti-fogging properties of the endoscope cover 1 may be reduced, which is not preferred.

[0085] Examples of the hydrophobic monomer include siloxane (meth)acrylate, trifluoroethyl (meth)acrylate, methacrylamide, cyclohexyl (meth)acrylate, and n-butyl (meth)acrylate. Two or more hydrophobic monomers may be used in combination.

[0086] The hydrophobic monomer can change the water content of the endoscope cover 1 by varying the amount of the monomer blended. However, if the blending ratio of the hydrophobic monomer is high, the water content is extremely low, and the flexibility of the endoscope cover 1 is reduced. Therefore, the hydrophobic monomer is preferably present in an amount of less than 30% by weight relative to the total amount of the monomers.

[0087] Examples of the crosslinking monomer include ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, methylenebisacrylamide, 2-hydroxy-1,3-dimethacryloxypropane, and trimethylolpropane triacrylate. At least one of these monomers or a combination of two or more thereof can be used.

[0088] The amount of the crosslinkable monomer blended is preferably 0.1 to 10% by weight relative to the total amount of monomers from the viewpoint of the shape adjustment effect of the endoscope cover 1. If it is less than 0.1% by weight, the lattice structure of the endoscope cover 1 is insufficient, while if it is greater than 10% by weight, the lattice structure is excessive, resulting in brittleness and reduced flexibility of the endoscope cover 1.

[0089] Examples of polymerization initiators used when polymerizing the above-mentioned monomer mixture include conventional free radical polymerization initiators, i.e., peroxides such as lauroyl peroxide, cumene hydroperoxide, and benzoyl peroxide, and azobisvaleronitrile and azobisisobutyronitrile. The amount of the polymerization initiator added is preferably about 100 to 10,000 ppm relative to the total amount of the monomers.

[0090] When a cross-linked hydrophilic polymer (hydrogel) is selected as the material of the annular member 6 that forms part of the distal end portion 8 of the endoscope cover 1 according to the present embodiment, as described above, by increasing the amount of cross-linking monomer blended into the polymerizable composition for forming the annular member 6 relative to the amount of cross-linking monomer blended into the polymerizable composition for forming the main body 5, the cross-linking density of the annular member 6 is made higher than that of the main body 5. This allows the distal end portion 8 to have a preferred strength when the annular member 6 (second distal end portion 7) is combined with the main body 5 to form the endoscope cover 1 according to the present embodiment.

[0091] The amount of the crosslinkable monomer used to form the annular member 6 varies depending on the molecular weight of the crosslinkable monomer used. For low molecular weight monomers, the amount is preferably 5 to 25% by weight, more preferably 10 to 20% by weight, of the total weight of the monomers forming the main body 5. For high molecular weight monomers, the amount is preferably 25 to 50% by weight, more preferably 30 to 40% by weight, of the total weight of the monomers forming the main body 5.

[0092] In the endoscope cover 1 according to this embodiment, the above-mentioned monomers are mixed in a single form or in a plurality of forms and then formed into a desired shape. In the first embodiment, the cover is formed from a single material, but in the second embodiment, the outer cover 2 and the disc portion 3 can be formed from different materials and then used in combination. In this case, by preparing the disc portion 3 so that the water content is higher than that of the outer cover 2, the anti-fog and anti-fouling properties can be more effectively exerted.

[0093] As a process for obtaining a polymer, a monomer mixture obtained by mixing monomers as constituent components is placed in a molding die made of metal, glass, plastic, or the like, sealed, and heated in a thermostat or the like in stages or continuously within a range of 25 to 120°C to complete a copolymerization reaction in 5 to 120 hours, whereby a molding die containing the polymer can be obtained. Regarding polymerization, ultraviolet rays, electron rays, γ-rays, or the like can be used.

[0094] As a process for obtaining a hydrogel, the molding die after the completion of polymerization is cooled to room temperature, the polymer placed in the molding die is peeled off from the molding die, and after cutting and polishing as needed, the polymer is hydrated and swollen to become a hydrogel.

[0095] Examples of the liquid (swelling liquid) used include water, physiological saline, isotonic buffer solutions, and solutions in which organic solvents such as ethanol are mixed in these, but are not limited to these. The swelling liquid is heated to 60 to 100°C, and the polymer is immersed in the swelling liquid for a certain period of time to be in a swollen state. In addition, it is preferable to remove unreacted monomers attached to the polymer during the swelling treatment. In a state where the obtained hydrogel is immersed in a swelling liquid such as physiological saline, it can be shaped by autoclaving at 110 to 130°C for 10 to 60 minutes.

[0096] Examples

[0097] Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.

[0098] (Method for manufacturing the endoscope cover 1)

[0099] <Example 1>

[0100] The circular ring member 6 of the endoscope cover 1 according to Example 1 is formed of an elastomer.

[0101] In Example 1, first, after subjecting a silicone rubber circular ring member 6 preformed into a desired shape by injection molding to a corona discharge treatment, it is placed on the tip 8 of a molding die for forming the endoscope cover 1 designed in advance so as to have the structure of the endoscope cover 1 shown in Table 1 after swelling.

[0102] Second, after mixing 99.0 g of 2-hydroxyethyl methacrylate as a hydrophilic monomer for forming the main body portion 5, 1.0 g of ethylene glycol dimethacrylate as a crosslinking monomer, and 0.20 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it is dispensed into the above-mentioned molding die in a state where the circular ring member 6 is placed, and heated polymerization is carried out (in a nitrogen atmosphere, heated from room temperature to 100°C, 40 hours).

[0103] 3. The obtained copolymer is swollen by heating in physiological saline at 60°C for 30 minutes, and then autoclaved to produce the endoscope cover 1.

[0104] <Example 2>

[0105] The ring member 6 of the endoscope cover 1 according to Example 2 is formed of a thermoplastic polymer.

[0106] In Example 2, first, after subjecting a pre-formed circular member made of polyvinyl chloride (PCV) to the desired shape by injection molding to corona discharge treatment, it is placed on the top portion 8 of a molding die for forming the endoscope cover 1 which is pre-designed to have the structure of the endoscope cover 1 shown in Table 1 after swelling.

[0107] Second, after mixing 99.0 g of 2-hydroxyethyl methacrylate as a hydrophilic monomer for forming the main body portion 5, 1.0 g of ethylene glycol dimethacrylate as a crosslinking monomer, and 0.30 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it is dispensed into the above molding die in a state where the circular member is placed, and heated polymerization is carried out (in a nitrogen atmosphere, heated from room temperature to 100°C for 40 hours).

[0108] 3. The obtained copolymer is swollen by heating in physiological saline at 60°C for 30 minutes, and then autoclaved to produce the endoscope cover 1.

[0109] <Example 3>

[0110] The ring member 6 of the endoscope cover 1 according to Example 3 is formed of a thermoplastic acrylic resin.

[0111] In Example 3, first, after mixing 90.0 g of methyl methacrylate as a monomer for forming the circular member 6, 10.0 g of PEG#200 dimethacrylate (4EG) as a crosslinking monomer, and 0.30 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it is dispensed into a molding die for forming the endoscope cover, and heated polymerization is carried out (in a nitrogen atmosphere, heated from room temperature to 100°C for 40 hours). After subjecting the obtained circular member made of polymethyl methacrylate (PMMA) to corona discharge treatment, it is placed on the top portion 8 of a molding die for forming the endoscope cover 1 which is pre-designed to have the structure of the endoscope cover 1 shown in Table 1 after swelling.

[0112] Second, after mixing 99.5 g of 2-hydroxyethyl methacrylate as a hydrophilic monomer for forming the main body part 5, 0.5 g of ethylene glycol dimethacrylate as a crosslinking monomer, and 0.30 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it is dispensed into the above-mentioned molding die in the state of a copolymerized circular part, and new heat polymerization is carried out (in a nitrogen atmosphere, heated from room temperature to 100 °C for 40 hours).

[0113] Third, the obtained copolymer is swollen by heating in physiological saline at 60 °C for 30 minutes, and high-pressure steam sterilization is carried out to produce the endoscope cover 13.

[0114] <Example 4>

[0115] The circular part 6 of the endoscope cover 1 according to Example 4 is formed of a hydrogel of the same material as the main body part 5.

[0116] In Example 3, first, after mixing 80.0 g of 2-hydroxyethyl methacrylate as a hydrophilic monomer for forming the circular part 6, 20.0 g of PEG#200 dimethacrylate (4EG) as a crosslinking monomer, and 0.30 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, after swelling, it is dispensed into a molding die for forming the endoscope cover 1 which is pre-designed to have the structure of the outer package part 2 shown in Table 1, and heat polymerization is carried out (in a nitrogen atmosphere, heated from room temperature to 100 °C for 40 hours).

[0117] Second, after mixing 96.5 g of 2-hydroxyethyl methacrylate as a hydrophilic monomer for forming the main body part 5, 3.5 g of PEG#200 dimethacrylate (4EG) as a crosslinking monomer, and 0.15 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it is dispensed into the above-mentioned molding die in the state of a copolymerized circular part, and new heat polymerization is carried out (in a nitrogen atmosphere, heated from room temperature to 100 °C for 40 hours).

[0118] Third, the obtained copolymer is swollen by heating in physiological saline at 60 °C for 30 minutes, and high-pressure steam sterilization is carried out to produce the endoscope cover 14.

[0119] <Example 5>

[0120] The circular part 6 of the endoscope cover 1 according to Example 5 is formed of a hydrogel of a material different from that of the main body part 5.

[0121] In Example 4, first, after mixing 70.0 g of 2-hydroxyethyl methacrylate as a hydrophilic monomer for forming the annular member 6, 30.0 g of trimethylolpropane triacrylate (TMPTA) as a crosslinking monomer, and 0.30 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it was dispensed into a molding die for forming the endoscope cover 1 which was pre-designed to have the structure of the endoscope cover 1 shown in Table 1 after swelling, and heated polymerization was carried out (in a nitrogen atmosphere, heated from room temperature to 100 °C, for 40 hours).

[0122] Second, after mixing 67.5 g of N,N-dimethyl(meth)acrylamide and 27.5 g of N-vinylpyrrolidone as hydrophilic monomers for forming the main body part 5, 5.0 g of PEG#200 dimethacrylate (4EG) as a crosslinking monomer, and 0.15 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it was dispensed into the above molding die in the state of the copolymerized annular member, and new heating polymerization was carried out (in a nitrogen atmosphere, heated from room temperature to 100 °C, for 40 hours).

[0123] Third, the obtained copolymer was swollen by heating at 60 °C in physiological saline for 30 minutes, and high-pressure steam sterilization was carried out to produce the endoscope cover 15.

[0124] <Comparative Example 1>

[0125] In the endoscope cover 1 related to Comparative Example 1, the ring member 6 was not provided.

[0126] In Comparative Example 1, first, after mixing 99.0 g of 2-hydroxyethyl methacrylate as a hydrophilic monomer for forming the main body part 5, 1.0 g of ethylene glycol dimethacrylate as a crosslinking monomer, and 0.30 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, it was dispensed into the above molding die in the state without the annular member 6, and heated polymerization was carried out (in a nitrogen atmosphere, heated from room temperature to 100 °C, for 40 hours).

[0127] Second, the obtained copolymer was swollen by heating at 60 °C in physiological saline for 30 minutes, and high-pressure steam sterilization was carried out to produce the endoscope cover 1.

[0128] (Evaluation of physical properties)

[0129] Examples 1 to 5 and Comparative Example 1 were evaluated according to the following criteria.

[0130] (Strength of the annular part)

[0131] For Examples 1 to 5, the compressive stress of the formed annular member was calculated as follows. For Comparative Example 1, the compressive stress of the annular portion 6 formed by the same method as in Example 3 was calculated as follows.

[0132] The annular portions 6 of Examples 1 to 5 and Comparative Example 1 formed into the shapes shown in Table 1 were set in a compression flexure testing machine (manufactured by Shimadzu Corporation / model EZ-SX50N) with the opening facing forward, and then loading was started. At the time point when the original outer diameter of the test piece (annular member) was compressed by 30%, the load amount was measured and defined as the compressive stress.

[0133] (Evaluation method)

[0134] The compressive stresses of 10 samples were measured respectively, and the average value of the 10 samples was calculated as the 30% deformation compression flexure strength (N) of Examples 1 to 5 and Comparative Example 1, and evaluation was performed according to the following criteria.

[0135] ○: The compressive stress is 1.0 N to 2.0 N.

[0136] △: The compressive stress is less than 1.0 N or the compressive stress is greater than 2.0 N.

[0137] ×: Unable to measure.

[0138] The evaluation method for the elasticity of the tip portion is as described below.

[0139] [Table 1]

[0140]

[0141]

[0142]

[0143] According to the endoscope cover 1 according to the present embodiment, since the anti-fogging property or anti-fouling property is excellent, during surgery or examination, the body fluid or grease attached to the lens portion of the endoscope can be easily removed by the water ejected from the water supply mechanism installed in the endoscope, and moreover, atomization can be suppressed.

[0144] In addition, according to the endoscope cover 1 according to the present embodiment, since the tip portion has sufficient strength and elasticity for pushing away biological tissues, the operability is improved when using the endoscope.

[0145] As described above, the present invention has been described using the above embodiments, but the descriptions and drawings that are part of the disclosure of the embodiments should not be construed as limiting the present invention. Those skilled in the art can clearly know various alternative embodiments, examples and application techniques from the disclosure.

Claims

1. An endoscope cover, characterized in that: The endoscope cover has: A main body portion made of hydrogel; and A second tip portion, The main body portion has: An outer package portion, which is in a substantially cylindrical shape; A disc portion, whose entire circumference is in contact with the inner side surface of the outer package portion; and A first tip portion, which is connected to the insertion-side end portion of the outer package portion, The second tip portion is connected to the insertion-side end portion of the first tip portion and includes an annular member.

2. The endoscope cover according to claim 1, characterized in that: The 30% deformation compression flexural strength of the annular member is stronger than the 30% deformation compression flexural strength of the main body portion.

3. The endoscope cover according to claim 1, characterized in that: The annular portion is selected from thermoplastic elastomers and thermosetting elastomers. The thermoplastic elastomers are selected from styrene-based, olefin-based, PVC-based, EVA-based, urethane-based, and acrylic-based. The thermosetting elastomers are selected from vulcanized rubber and resin-based elastomers.

4. The endoscope cover according to claim 1, characterized in that: The annular portion is selected from thermosetting polymers having elasticity.

5. The endoscope cover according to any one of claims 1 to 4, characterized in that: The 30% deformation compression flexural strength of the annular portion is 1.0 N to 2.0 N.

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