Hydrophilized ePTFE sheet and method for hydrophilizing ePTFE sheet

Abstract

To provide a hydrophilized ePTFE sheet that can be used for applications such as implantation in the human body or attachment to the surface of an organ by increasing hydrophilicity. [Solution] The hydrophilized ePTFE sheet 10 is composed of an ePTFE sheet 12, Japanese paper 14 laminated on the surface of the ePTFE sheet 12 which has been treated with atmospheric pressure plasma, and a collagen layer 16 applied to the surface of the Japanese paper 14.

Description

[Technical field]

[0001] The present invention relates to an ePTFE sheet which has high biocompatibility and has been made hydrophilic, and to a method for making a highly biocompatible ePTFE sheet hydrophilic. [Background technology]

[0002] Inert, thin, lightweight, and durable ePTFE (extendable ShinP TFE (polytetrafluoroethylene) is used in various fields such as gland packing, gaskets, and architectural fabrics (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Application No. 2016-138188 Summary of the Invention [Problem to be solved by the invention]

[0004] However, ePTFE is hydrophobic, making it difficult to bond to other dissimilar materials.

[0005] In particular, it has been difficult to take advantage of the biocompatibility of ePTFE and use it in applications such as implanting it in the human body or attaching it to the surface of an organ, etc.

[0006] The present invention has been made in consideration of these problems, and its object is to provide a hydrophilized ePTFE sheet that has enhanced hydrophilicity and can be used for applications such as implantation in the human body or attachment to the surface of an organ, etc., and a method for hydrophilizing an ePTFE sheet. [Means for solving the problem]

[0007] According to one aspect of the present invention, An ePTFE sheet; Japanese paper laminated on the surface of the atmospheric pressure plasma-treated ePTFE sheet; A collagen layer is applied to the surface of the Japanese paper. A hydrophilized ePTFE sheet is provided.

[0008] Preferably, The surface of the collagen layer is subjected to ion beam irradiation.

[0009] According to another aspect of the present invention, The surface of the ePTFE sheet is treated with atmospheric pressure plasma. Laminating Japanese paper on the surface that has been subjected to the atmospheric pressure plasma treatment; A collagen layer is applied to the surface of the washi paper. A method for hydrophilizing an ePTFE sheet is provided.

[0010] Preferably, The surface of the collagen layer is irradiated with an ion beam. Effect of the Invention

[0011] The hydrophilic ePTFE sheet of the present invention is prepared by laminating Japanese paper on the surface of an ePTFE sheet that has been subjected to atmospheric pressure plasma treatment, and then applying a collagen layer to the surface of the Japanese paper. This makes it possible to provide ePTFE with enhanced hydrophilicity on the surface. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing an example of a hydrophilized ePTFE sheet 10 according to an embodiment. [Diagram 2] FIG. 1 is a diagram showing a manufacturing process of a hydrophilized ePTFE sheet 10. [Diagram 3] FIG. 1 is a diagram showing a manufacturing process of a hydrophilized ePTFE sheet 10. [Figure 4] FIG. 13 is a diagram for explaining a contact angle. [Diagram 5] FIG. 1 is a diagram illustrating an example of the principle of electron beam irradiation. [Figure 6] FIG. 1 is a diagram showing an example of ion beam irradiation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] (Configuration of hydrophilic ePTFE sheet 10) As shown in FIG. 1, the hydrophilized ePTFE sheet 10 according to this embodiment generally comprises an ePTFE sheet 12, Japanese paper 14, and a collagen layer 16.

[0014] The ePTFE sheet 12 preferably has a thickness of 50 μm to 500 μm.

[0015] The surface of this ePTFE sheet 12 is subjected to atmospheric pressure plasma treatment, as shown in Fig. 2. Atmospheric pressure plasma treatment can change the hydrophobic ePTFE sheet 12 to hydrophilicity, making it possible to laminate films, cellulose, etc., which would not normally adhere to the ePTFE sheet, onto the ePTFE sheet.

[0016] The washi paper 14 is a member laminated on the surface of the ePTFE sheet 12 that has been subjected to atmospheric pressure plasma treatment, and in this specification refers to a film formed by adding plant-derived cellulose fibers to an aqueous solution of polysaccharides, stirring, and dispersing them uniformly. It is preferable to use washi paper 14 with a thickness of 10 μm to 100 μm. The washi paper 14 uses very fine cellulose fibers obtained from plant fibers, particularly the epidermis of paper mulberry, gampi, and mitsumata, and the polysaccharides used for suspension are obtained from Abelmoschus aureus and are sometimes used as food additives. Since no chemicals are used, it is not irritating to the living body and can be said to be a material with excellent biocompatibility.

[0017] One method for laminating Japanese paper 14 onto the surface of ePTFE sheet 12 is, for example, to heat Japanese paper 14 to 100°C to 200°C, heat ePTFE sheet 12 to 150°C to 200°C, and then pressurize Japanese paper 14 onto the surface of ePTFE sheet 12 at 0.2 MPa to 1.0 MPa (see Figure 3).

[0018] The collagen layer 16 is a layer of collagen solution applied to the surface of the Japanese paper 14. A specific example of the collagen solution is Type I "AteloCell (catalog number: IPC-50)" by Koken Co., Ltd. The thickness of the collagen layer 16 is preferably 10 μm to 40 μm.

[0019] The collagen layer 16 can be formed, for example, by diluting the collagen solution stock solution by at least two times with purified water, and immersing the Japanese paper 14 laminated on the surface of the ePTFE sheet 12 in the diluted collagen solution to uniformly coat it. The ePTFE sheet 12 and the Japanese paper 14 are then removed from the diluted collagen solution and air-dried. This process is repeated multiple times, and the diluted collagen solution is then completely dried. At this stage, a hydrophilized ePTFE sheet 10 is completed, as shown in FIG. 1.

[0020] The contact angle of the completed hydrophilized ePTFE sheet 10 on the side where the collagen layer 16 is formed and the contact angle on the opposite side are measured, and it is confirmed that the contact angle on the side where the collagen layer 16 is formed is 90° or less and the contact angle on the opposite side is 90° or more. The "contact angle" is one of the indices in wettability evaluation, and is a numerical value of the degree of swelling of a droplet that occurs when a liquid is dropped on a solid. Specifically, as shown in FIG. 4, the liquid attached to the upper surface of the solid is observed from the side, and the angle θ of the liquid at the end point of the droplet is measured with respect to the solid surface.

[0021] Furthermore, the amount of liquid adhering to the side on which the collagen layer 16 is formed and the amount of liquid adhering to the opposite side are measured, respectively, of the hydrophilized ePTFE sheet 10. It is confirmed that the amount of liquid adhering to the side on which the collagen layer 16 is formed is 40% or less after 30 seconds has elapsed, and that the amount of liquid adhering to the opposite side remains unchanged even after 30 seconds or more have elapsed.

[0022] (Variation 1) In the above-described embodiment, the hydrophilized ePTFE sheet 10 is completed by forming a collagen layer 16 on the surface of the Japanese paper 14, but the surface of this collagen layer 16 may be further irradiated with an ion beam, electromagnetic wave, or electron beam.

[0023] The principle of electron beam irradiation (thermionic type) can be briefly explained using Figure 5. When an electric current is passed through a tungsten filament placed in the center of a vacuum chamber, the filament is heated and emits thermoelectrons. The emitted thermoelectrons are first extracted to a grid. These thermoelectrons are then accelerated to nearly the speed of light by a high voltage (accelerating voltage) of 80 to 300 kV between the terminal and the anode window, becoming an electron stream that passes through the thin foil (aluminum or titanium) of the window and is emitted into the outside world as an electron beam. This electron beam is used in electron beam irradiation.

[0024] An example of ion beam irradiation will be briefly described below. An ion beam irradiation device 50 according to one example includes an ion source 52, an ion acceleration tube 54, a mass analyzer 56, a scanner 58, and a sample chamber 60, as shown in FIG.

[0025] First, the ePTFE sheet 10, which has the collagen layer 16 formed on the surface of the Japanese paper 14 to be irradiated with the ion beam, is placed in the sample chamber 60. Thereafter, ions are generated in the ion source 52, and the ions are accelerated by an electric field in the ion acceleration tube 54. From the accelerated ions, only ions with a mass required for irradiation are selected in the mass analyzer 56. The selected ions are scanned by the scanner 58 so that they are irradiated over the entire ePTFE sheet 10. The voltage in the ion acceleration tube 54 is 50 KeV to 200 KeV, and the pressure in the sample chamber 60 is 10 -4 Pa to 10 -5 The pressure is negative at 1 Pa.

[0026] In the case of a hydrophilized ePTFE sheet 10 completed by forming a collagen layer 16 on the surface of Japanese paper 14, platelets in blood have the property of easily adhering to the surface of the collagen layer 16, so the hydrophilized ePTFE sheet 10 is unsuitable for use in a position where blood may adhere. However, when the surface of the collagen layer 16 is irradiated with an ion beam or electromagnetic wave / electron beam, platelets become less likely to adhere to the surface of the collagen layer 16, so the hydrophilized ePTFE sheet 10 that has been irradiated with an ion beam can be actively used in a position where blood may adhere.

[0027] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the scope and meaning equivalent to the claims. [Explanation of symbols]

[0028] 10...hydrophilized ePTFE sheet, 12...ePTFE sheet, 14...Japanese paper, 16...collagen layer 50... ion beam irradiation device, 52... ion source, 54... ion acceleration tube, 56... mass analyzer, 58... scanner, 60... sample chamber

Claims

1. An ePTFE sheet; Japanese paper laminated on the surface of the ePTFE sheet that has been treated with atmospheric pressure plasma; A collagen layer is applied to the surface of the Japanese paper. Hydrophilized ePTFE sheet.

2. The surface of the collagen layer is irradiated with an ion beam.

2. The ePTFE sheet of claim 1.

3. The surface of the ePTFE sheet is subjected to atmospheric pressure plasma treatment; Laminating Japanese paper on the surface that has been subjected to the atmospheric pressure plasma treatment; A collagen layer is applied to the surface of the washi paper. A method for making an ePTFE sheet hydrophilic.

4. The surface of the collagen layer is irradiated with an ion beam. The method for hydrophilization according to claim 3.

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