Endoscope, cylindrical covering member for endoscope, and method for manufacturing cylindrical covering member for endoscope

Abstract

To provide a cylindrical cover member for an endoscope that has excellent adhesiveness and flexibility, and to provide an endoscope and a method for manufacturing a cylindrical cover member for an endoscope.SOLUTION: An endoscope includes a member including a non-liquid fluorine-based elastomer and a liquid fluorine-based elastomer. A low-density area where density of the liquid fluorine-based elastomer is lower than that in an inside of the member is present at a surface of the member.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an endoscope, a tubular covering member for an endoscope, and a method for manufacturing a tubular covering member for an endoscope. [Background technology]

[0002] Elastomer molded articles made of fluoroelastomers with excellent chemical resistance are used for cylindrical covering members such as the outer cover of a bending tube of an endoscope (see, for example, Patent Document 1). Flexibility is required for cylindrical covering members to allow for light force during bending operations. To impart flexibility to the cylindrical covering member, a liquid fluoroelastomer is blended in addition to a non-liquid fluoroelastomer. The liquid fluoroelastomer is a low-molecular-weight liquid fluoroelastomer that does not undergo a crosslinking reaction with the non-liquid fluoroelastomer and does not have a crosslinking reactive group.

[0003] In some cases, a cylindrical covering member is covered with another covering member for use. In such cases, the cylindrical covering member and the other covering member are bonded together, but this has the problem of low adhesive strength.

[0004] On the other hand, a method has been proposed for modifying the surface of a fluorine-based resin molded article, in which the surface is treated with an etching solution and then washed with a non-ketone solvent (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2011 / 126017 [Patent Document 2] Japanese Patent Application Publication No. 10-298316 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when an elastomer molded body is treated by the method of Patent Document 2, there is a problem in that the etching solution impairs the physical properties of the elastomer, particularly its flexibility.

[0007] The present invention has been made in view of the above, and has as its object to provide a tubular covering member for an endoscope, an endoscope, and a method for manufacturing a tubular covering member for an endoscope that are excellent in adhesiveness and flexibility. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems and achieve the object, an endoscope according to the present invention is characterized in that, in an endoscope having a member containing a non-liquid fluorine-based elastomer and a liquid fluorine-based elastomer, a low-density region in which the density of the liquid fluorine-based elastomer is lower than that inside the member is present on the surface of the member. Here, "low density" also includes the absence of the liquid fluorine-based elastomer.

[0009] Furthermore, in the endoscope according to the present invention, in the above invention, the low-density region of the liquid fluorine-based elastomer is formed in at least a part of the region where the member connects to another member.

[0010] Furthermore, in the endoscope according to the present invention, in the above invention, the low-density region of the liquid fluorine-based elastomer is a region where the liquid fluorine-based elastomer is eluted from the surface of the member by application of a solvent and / or immersion in a solvent, and the solvent contains at least one solvent selected from tetrahydrofuran (THF), acetone, diethyl ether, propylene glycol monopropyl ether, butyl lactate, ethyl lactate, ethyl acetoacetate, dimethyl adipate, diethyl adipate, propyl formate, and dibutyl maleate.

[0011] In addition, the endoscope according to the present invention is characterized in that, in the above invention, the member is a bending portion outer shell, and the other member is a tip portion or a flexible tube outer shell.

[0012] Furthermore, the present invention provides a cylindrical covering member for an endoscope, which comprises a non-liquid fluorine-based elastomer and a liquid fluorine-based elastomer, characterized in that a low-density region is present on the surface of the cylindrical covering member for an endoscope, in which the density of the liquid fluorine-based elastomer is lower than that inside the cylindrical covering member for an endoscope.

[0013] The cylindrical covering member for an endoscope according to the present invention is characterized in that, in the above invention, it is an outer cover of a bending portion.

[0014] Furthermore, the method for producing a cylindrical covering member for an endoscope according to the present invention is a method for producing a cylindrical covering member for an endoscope containing a non-liquid fluorine-based elastomer and a liquid fluorine-based elastomer, characterized in that it comprises a step of eluting the liquid fluorine-based elastomer from the surface of the cylindrical covering member for an endoscope using a solvent that satisfies the following formula (1): |HSP S -HSP E |≦5.6···(1) HSP S : Hansen solubility parameters of the solvent HSP E : Hansen solubility parameters of liquid fluoroelastomers

[0015] Furthermore, the method for producing a tubular covering member for an endoscope according to the present invention is characterized in that, in the above invention, the solvent contains at least one solvent selected from tetrahydrofuran (THF), acetone, diethyl ether, propylene glycol monopropyl ether, butyl lactate, ethyl lactate, ethyl acetoacetate, dimethyl adipate, diethyl adipate, propyl formate, and dibutyl maleate. [Effects of the Invention]

[0016] According to the present invention, when another member is adhered to a tubular covering member for an endoscope, the flexibility of the tubular covering member for an endoscope can be maintained while preventing the other member from peeling off from the tubular covering member for an endoscope. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram schematically illustrating the overall configuration of an endoscope system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, embodiments of an endoscope, a tubular covering member for an endoscope, and a method of manufacturing a tubular covering member for an endoscope according to the present invention will be described with reference to the drawings. Note that the present invention is not limited to the following embodiments, and the components in the following embodiments include those that are easily replaceable by those skilled in the art, or those that are substantially identical.

[0019] (Embodiment) Fig. 1 is a diagram schematically illustrating the overall configuration of an endoscope system 1 according to an embodiment of the present invention. As shown in Fig. 1, the endoscope system 1 according to this embodiment includes an endoscope 2 that is introduced into a subject and captures images of the inside of the subject's body to generate image signals of the inside of the subject, an information processing device 3 that performs predetermined image processing on the image signals captured by the endoscope 2 and controls each unit of the endoscope system 1, a light source device 4 that generates illumination light for the endoscope 2, and a display device 5 that displays an image of the image signal after image processing by the information processing device 3.

[0020] The endoscope 2 comprises an insertion section 6 that is inserted into the subject, an operating section 7 that is located at the base end of the insertion section 6 and is held by the surgeon, and a flexible universal cord 8 that extends from the operating section 7.

[0021] The insertion section 6 is realized using a light guide made of an illumination fiber, an electric cable, an optical fiber, or the like. The insertion section 6 has a tip section 6a with a built-in imaging device, a freely bendable bending section 6b equipped with a bending tube described later, and a flexible tube section 6c provided on the proximal end side of the bending section 6b. The tip section 6a is provided with an illumination section that illuminates the inside of the subject via an illumination lens, an observation section that images the inside of the subject, and an opening that communicates with a treatment tool channel. An endoscope tip frame described later is disposed at the tip section 6a.

[0022] The operation unit 7 has a bending knob 7a that bends the bending portion 6b in the up-down and left-right directions, a treatment tool insertion portion 7b into which treatment tools such as biological forceps and a laser scalpel are inserted into the body cavity of the subject, and a plurality of switches 7c that operate peripheral devices such as the information processing device 3, light source device 4, air supply device, water supply device, gas supply device, and bending tube. The treatment tool inserted through the treatment tool insertion portion 7b passes through a treatment tool channel provided inside and emerges from an opening at the tip of the insertion portion 6.

[0023] The universal cord 8 is configured using a light guide made of illumination fiber, a cable, etc. The universal cord 8 branches at the base end, with one branched end being a connector 8a and the other base end being a connector 8b. The connector 8a is detachable from a connector of the information processing device 3. The connector 8b is detachable from the light source device 4. The universal cord 8 transmits illumination light emitted from the light source device 4 to the tip end 6a via the connector 8b and a light guide made of illumination fiber. The universal cord 8 also transmits image signals captured by an imaging device (described later) to the information processing device 3 via the cable and connector 8a.

[0024] The information processing device 3 performs predetermined image processing on the image signal output from the connector 8a, and also controls the entire endoscope system 1.

[0025] The light source device 4 is configured using a light source that emits light, a condenser lens, etc. Under the control of the information processing device 3, the light source device 4 emits light from the light source and supplies it to the endoscope 2 connected via the connector 8b and a light guide made up of an illumination fiber of the universal cord 8 as illumination light for the inside of the subject, which is the object of the examination.

[0026] The display device 5 is configured using a display using liquid crystal or organic EL (Electro Luminescence), etc. The display device 5 displays various information including images that have been subjected to predetermined image processing by the information processing device 3 via a video cable 5a. This allows the surgeon to operate the endoscope 2 while viewing the image (intra-body image) displayed by the display device 5, thereby enabling observation of a desired position inside the subject and diagnosis of symptoms.

[0027] Next, we will explain the cylindrical covering member for an endoscope used as the outer cover of the bending portion 6b of the endoscope 2. The cylindrical covering member for an endoscope contains a non-liquid fluorine-based elastomer and a liquid fluorine-based elastomer.

[0028] The non-liquid fluorine-based elastomers used in the present invention include vinylidene fluoride / hexafluoropropylene copolymers (e.g., Dai-el (registered trademark) G-801 manufactured by Daikin Industries, Ltd., and Dyneon (registered trademark) Florel FC-2260 manufactured by 3M), vinylidene fluoride / hexafluoropropylene / tetrafluoroethylene copolymers (e.g., Viton (registered trademark) GF manufactured by DuPont, Dai-el (registered trademark) G-902 manufactured by Daikin Industries, Ltd., and Dai-el (registered trademark) G-912 manufactured by Daikin Industries, Ltd., and 3M Examples of such copolymers include Dyneon (registered trademark) Florel FLS-2650, Tecnoflon (registered trademark) P959 manufactured by Solvay, vinylidene fluoride / perfluoroalkyl vinyl ether / tetrafluoroethylene copolymers (e.g., Viton (registered trademark) GLT manufactured by DuPont), tetrafluoroethylene / propylene copolymers (e.g., Aflas (registered trademark) manufactured by AGC), and ethylene / tetrafluoroethylene / perfluoroalkyl vinyl ether copolymers (e.g., Viton (registered trademark) EPT manufactured by DuPont).

[0029] The liquid fluorine-based elastomer is a low-molecular-weight fluorine-based elastomer that does not have a crosslinking reactive group, and an example of the liquid fluorine-based elastomer is Daiel G101 manufactured by Daikin Industries, Ltd.

[0030] The compounding ratio of the non-liquid fluorine-based elastomer to the liquid fluorine-based elastomer is preferably 1 to 50 parts by mass, more preferably 1 to 15 parts by mass, of the liquid fluorine-based elastomer per 100 parts by mass of the non-liquid fluorine-based elastomer.

[0031] The cylindrical covering member for an endoscope may also contain components such as a cross-linking agent, a cross-linking assistant, a coloring agent, a reinforcing material, and a filler.

[0032] As the crosslinking agent, it is preferable to use a peroxide from the viewpoint of chemical resistance, and examples thereof include dicumyl peroxide, di-t-butylperoxydiisopropylbenzene, and 2,5-dimethyl-2,5-di(t-butylperoxy)hexane.

[0033] Examples of the crosslinking aid include triallyl isocyanurate, triallyl cyanurate, triallyl trimellitate, N,N'-m-phenylenedimaleimide, and trimethylolpropane trimethacrylate.

[0034] An example of the coloring agent is reinforcing carbon.

[0035] An example of the reinforcing material is silica.

[0036] Examples of fillers include inorganic fillers such as carbon black, silica, barium sulfate, titanium oxide, aluminum oxide, calcium carbonate, calcium silicate, magnesium silicate, and aluminum silicate, and organic fillers such as polytetrafluoroethylene resin, polyethylene resin, polypropylene resin, phenolic resin, polyimide resin, melamine resin, and silicone resin.

[0037] The surface of the cylindrical covering member for an endoscope according to this embodiment has a low-density region where the density of the liquid fluorine-based elastomer is lower than that of the interior. The low-density region of the liquid fluorine-based elastomer is a region where the liquid fluorine-based elastomer is eluted from the surface of the cylindrical covering member for an endoscope by application of and / or immersion in a solvent.

[0038] The solvent to be applied to and / or immersed in the surface of the cylindrical covering member for an endoscope is a solvent that satisfies the following formula (1). |HSP S -HSP E |≦5.6···(1) HSP S : Hansen solubility parameters of the solvent HSP E : Hansen solubility parameters of liquid fluoroelastomers

[0039] Hansen solubility parameters are parameters used to predict the solubility of substances, and are composed of the energy due to intermolecular dispersion forces, the energy due to intermolecular dipole interactions, and the energy due to intermolecular hydrogen bonds. When the Hansen solubility parameters are placed in Hansen space, which considers the three parameters to be coordinates in three-dimensional space, the closer the distances, the easier it is considered to dissolve. The radius of the dissolving sphere of liquid fluoroelastomers calculated from the Hansen solubility parameters is 5.6, and solvents that satisfy equation (1) are thought to be able to dissolve liquid fluoroelastomers.

[0040] Examples of solvents that satisfy formula (1) include at least one selected from tetrahydrofuran (THF), acetone, diethyl ether, propylene glycol monopropyl ether, butyl lactate, ethyl lactate, ethyl acetoacetate, dimethyl adipate, diethyl adipate, propyl formate, and dibutyl maleate.

[0041] In the method for producing the cylindrical covering member for an endoscope according to this embodiment, first, a cylindrical molding is performed by any of various conventional methods. For example, the non-liquid fluoroelastomer as the main component and the filler are masticated in a kneading machine such as a twin-screw roll, kneader, or Banbury mixer, and various additives are added. For example, when crosslinking is performed using a crosslinking agent, the crosslinking agent and crosslinking aid are added while kneading, and finally, the liquid fluoroelastomer is added to prepare the molding raw material.

[0042] The obtained molding material is molded by a molding method such as injection molding, extrusion molding, transfer molding, etc. After molding, secondary crosslinking can be carried out in a hot air stream by irradiating with radiation or the like.

[0043] After molding, the surface of the cylindrical covering member for an endoscope is coated with and / or immersed in the above-mentioned solvent to elute the liquid fluorine-based elastomer on the surface side, thereby forming a low-density region where the density of the liquid fluorine-based elastomer is lower than that of other regions.

[0044] The non-liquid fluoroelastomer, the main component of a cylindrical endoscope covering, has residual cross-linking groups that participate in the reaction when bonding other components, thereby contributing to adhesiveness. However, it has been confirmed that the presence of a liquid fluoroelastomer reduces the reactivity of the cross-linking groups, as they are covered by the liquid fluoroelastomer and are unable to participate in adhesion. The inventors have discovered that applying and / or immersing the surface of a cylindrical endoscope covering in a solvent whose Hansen solubility parameter is similar to that of the liquid fluoroelastomer, i.e., which satisfies the above formula (1), can dissolve the liquid fluoroelastomer on the surface and form a low-density region where the density of the liquid fluoroelastomer is lower than that of other regions. The low-density region, where the density of the liquid fluoroelastomer is lower, can improve adhesive strength compared to other regions without impairing the physical properties of the cylindrical endoscope covering, such as flexibility.

[0045] The cylindrical covering member for an endoscope has a low-density region in which the density of the liquid fluorine-based elastomer is lower than that in other regions in at least a part of the region where the other member is connected, thereby improving the adhesion of the other member. An example of the cylindrical covering member for an endoscope is a bending tube outer cover, and an example of the other member to be connected is a tip portion or a flexible tube outer cover. [Example]

[0046] Hereinafter, an endoscope, a tubular covering member for an endoscope, and a method for manufacturing a tubular covering member for an endoscope according to the present embodiment will be described based on examples.

[0047] A molding material was obtained by blending 100 parts by weight of a non-liquid fluorine-based elastomer (ternary fluorine-containing rubber), 10 parts by weight of a liquid fluorine-based elastomer (liquid fluorine-containing rubber), 10 parts by weight of a crosslinking agent (organic peroxide), 2 parts by weight of a crosslinking coagent (triallyl isocyanurate), and thermal black and flat alumina as fillers. The mixture was kneaded on an open roll to obtain a molding material. This molding material was filled into a mold and crosslinked at 160°C for 10 minutes. Secondary crosslinking was then carried out in an oven at 200°C for 4 hours to obtain a bending tube outer shell for use as a cylindrical covering for endoscopes. The wall thickness of the molded product was approximately 0.5 mm. The surface of the molded product was wiped or immersed in the solvents listed in the table below, and the 50% modulus, puncture strength, and fracture mode were measured.

[0048] The 50% modulus was measured by cutting the outer sheath of the bendable pipe into a sheet and measuring the stress when the sheet was stretched by 50%. Values ​​of less than 1.3 MPa were evaluated as ◯, and values ​​of 1.3 MPa or more were evaluated as ×.

[0049] The puncture strength was evaluated by cutting the outer sheath of the curved pipe into a 0.5 mm thick test piece and using a pin with a tip diameter of 1.5 mm and a mass of 50 g. After dropping the pin onto the test piece from a specified height, a force of 0.5 kgf / cm was applied to one side of the test piece. 2 The presence or absence of air leakage to the other side was checked. No air leakage was marked with ○, and air leakage was marked with ×.

[0050] The fracture mode was evaluated as follows: when the outer sheath of the curved pipe was cut into sheets, glued together, and then peeled under load, if material fracture occurred, it was evaluated as ○, and if interfacial fracture occurred, it was evaluated as ×. Table 1 shows the solvents used and the evaluation results.

[0051] [Table 1]

[0052] As shown in Table 1, it was confirmed that solvents whose Hansen solubility parameters satisfy the above formula (1) have excellent flexibility and puncture resistance, as well as excellent adhesiveness, even after application or immersion in the solvent.

[0053] While the endoscope according to the present invention has been specifically described above using the preferred embodiments of the invention, the scope of the present invention is not limited to these descriptions and should be broadly interpreted based on the claims. It goes without saying that various modifications and alterations based on these descriptions are also included within the scope of the present invention. [Explanation of symbols]

[0054] 1. Endoscopy system 2 Endoscopy 3. Information processing equipment 4 Light source device 5 Display device 6 Insertion section 6a Tip 6b Curved section 6c Flexible tube section 7 Control section 7a Curved knob 7b Treatment tool insertion part 7c Switch section 8 Universal Code 8a, 8b connectors

Claims

1. In an endoscope having a member containing a non-liquid fluorine-based elastomer and a liquid fluorine-based elastomer, a low-density region in which the density of the liquid fluorine-based elastomer is lower than that of the interior of the member is present on the surface of the member; An endoscope, characterized in that the low-density region of the liquid fluorine-based elastomer overlaps at least a part of the region of the member that connects to another member.

2. 2. The endoscope according to claim 1, wherein the low-density region of the liquid fluorine-based elastomer is a region formed by elution of the liquid fluorine-based elastomer from the surface of the member.

3. 2. The endoscope according to claim 1, wherein the member is a bending portion outer cover, and the other member is a tip portion or a flexible tube outer cover.

4. A cylindrical covering member for an endoscope comprising a non-liquid fluorine-based elastomer and a liquid fluorine-based elastomer, a low-density region in which the density of the liquid fluorine-based elastomer is lower than that of the interior of the cylindrical covering member for an endoscope is present on the surface of the cylindrical covering member for an endoscope; A cylindrical covering member for an endoscope, wherein the low-density region of the liquid fluorine-based elastomer overlaps at least a part of a region of the cylindrical covering member for an endoscope that connects to another member.

5. 5. The cylindrical covering member for an endoscope according to claim 4, which is an outer cover of a bending portion.

6. A method for producing a cylindrical covering member for an endoscope, comprising: a method for producing a cylindrical covering member for an endoscope, the method comprising the step of eluting the liquid fluorine-based elastomer from a surface of the cylindrical covering member for an endoscope, the surface overlapping with at least a part of a region to which another member is connected, using a solvent satisfying the following formula (1): |HSP Ｓ -HSP Ｅ |≦5.6・・・(1) HSP Ｓ : Hansen solubility parameter of the solvent HSP Ｅ : Hansen solubility parameter of liquid fluorine-based elastomer

7. 7. The method for manufacturing a cylindrical covering member for an endoscope according to claim 6, wherein the solvent contains at least one selected from the group consisting of tetrahydrofuran (THF), acetone, diethyl ether, propylene glycol monopropyl ether, butyl lactate, ethyl lactate, ethyl acetoacetate, dimethyl adipate, diethyl adipate, propyl formate, and dibutyl maleate.

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