TWI675054B - Medical sheet and method of manufacturing same - Google Patents

Abstract

[Solution to Problem] Provide a medical sheet that can distinguish a surface (part) to which an ion impact is applied and a surface (part) to which an ion impact is not applied. [Solution means] A medical sheet, is provided as the value of b b roughened portion 3 ₁ b ₂ as the difference value and the value b value when the second surface 7 Δb, Δb 2 is less than 11; and A method for manufacturing a medical sheet, including: a roughening step of forming a roughened portion 3 of all or part of the first surface 5 of a sheet containing polytetrafluoroethylene by ion impact; Among them, the ion impact is continuously performed in a vacuum degree of 10 ^-7 pressure or more and 10 ^-1 pressure or less.

Description

Medical sheet and manufacturing method thereof

The present invention relates to a medical sheet. More specifically, the present invention relates to a medical sheet that can be used in bioremediation materials, artificial films, and the like.

Japanese Patent No. 4445697 and Japanese Patent No. 5505752 disclose a bioremediation material.

[Knowledge Technical Literature] [Patent Literature] [Patent Literature 1] Japanese Patent No. 4445697 [Patent Literature 2] Japanese Patent No. 5505752

[Problems to be Solved by the Invention] In the bioremediation material described in the above publication, it is difficult to distinguish between a surface to which ion impact is applied and a surface to which ion impact is not applied. Bioremediation materials or artificial membranes are buried in living organisms, etc., so it is difficult to use coloring materials, or it must be reconfirmed when the composition is changed. Therefore, there is a need for a medical sheet capable of distinguishing the surface (part) to which the ion impact is applied from the surface (part) to which the ion impact is not applied. Furthermore, there is a need for a person who is easy to fix vascular endothelial cells when making a vascular prosthesis using a medical sheet.

[Technical means to solve the problem] In principle, the present invention is based on the knowledge as described below: after all or part of the surface on the side of a resin sheet such as ePTFE (stretched polytetrafluoroethylene) is roughened by ion impact or the like The heat treatment is applied, whereby only the portion to which the roughening treatment is applied is discolored without changing the physical characteristics. In addition, the present invention is also based on the knowledge as described below: When performing ion impact, the vacuum degree of the ion impact device is maintained at a constant value, and the ion impact is continuously performed, thereby improving the effect of the ion impact and achieving a high degree of roughening.

The present invention relates to a medical sheet. This medical sheet is a medical sheet 1 containing polytetrafluoroethylene and includes: a first surface 5 having a roughened portion 3; and a second surface 7 on the opposite side of the first surface 5. Next, the roughened portion 3 has a Rz value of 8 or more and 14 or less and a Ra value of 0.65 or more and 1.5 or less as a surface roughness value. The roughened portion 3 is preferably a portion modified by ion impact. The roughened portion 3 may be a part of the first surface 5 or may be the entirety of the first surface 5. Provided surface roughening b value b ₁ of section 3 of the value as a difference value b ₂ b value when the second surface 7 Δb, Δb is preferably 2 or more and 11 or less.

The present invention also provides a method for manufacturing a medical sheet. This method is a method for manufacturing a medical sheet including a roughening step as described later. The whole or a part of the first surface 5 of a sheet containing polytetrafluoroethylene is roughened by ion impact to form a roughened surface. Department 3. Next, the ion impact is continuously performed in a vacuum degree of 10 ^-7 or more and 10 ^-1 or less. This method preferably further includes a heating step as described later: heating the sheet containing polytetrafluoroethylene after the roughening step to obtain a medical sheet. The roughened portion 3 preferably has an Rz value of 8 or more and 14 or less and a Ra value of 0.65 or more and 1.5 or less as a surface roughness value. The heating step is, for example, a step described below: heating the sheet at a temperature of 60 ° C. to 300 ° C. for 10 seconds or more and 10 minutes or less.

[Effects of the Invention] According to the present invention, it is possible to provide a method for manufacturing a medical sheet capable of producing a medical treatment that can distinguish between a surface (part) to which a roughening treatment is applied and a surface (part) to which a roughening treatment is not performed. With the sheet, the present invention can also provide a medical sheet that can be distinguished. In addition, when a vascular prosthesis is produced using this medical sheet, vascular endothelial cells can be easily fixed.

The following is a description of the mode for implementing the present invention using drawings. The present invention is not limited to those described in the following, but also includes those who have ordinary knowledge in the technical field from the following, and who can make appropriate modifications within the scope of obvious and obvious.

The present invention relates to a medical sheet. The medical sheet refers to a sheet as described later, which has a portion with high healing properties and low adhesion to biological tissues, and can be used in medical treatment. This sheet can be used for healing specific tissue on one side, for example, and the other side is not used for healing tissue. In addition, artificial blood vessels can be obtained by rolling up the medical sheet. Furthermore, the medical sheet can be used in artificial valves or various transplants by being cut into a predetermined shape or the like. The medical sheet may be a bioremediation material described in Japanese Patent No. 4445697, or a filling material having adhesiveness to artificial dura mater or muscle described in Japanese Patent No. 5505752. The optimal material for these flakes is an oval shape with a size ranging from 7.5 cm x 10.0 cm to 26.0 cm x 34.0 cm. And circular, quadrangular, triangular, and other planar shapes that are particularly suitable for fabrication are also contemplated for use in the present invention. Regardless of shape, suitable sizes of portable sheet materials range from a small range of 1.0cm × 1.0cm to a large range of 50.0cm × 50.0cm, preferably 5.0cm × 5.0cm ～ 40.0cm × 40.0cm The small flakes may be small flakes ranging from 7.0 cm × 7.0 cm to 20.0 cm × 20.0 cm.

As shown in FIG. 1, the medical sheet 1 is a medical sheet 1 containing polytetrafluoroethylene and includes: a first surface 5 having a roughened portion 3; and a second surface 7 opposite to the first surface 5. side. FIG. 1 is a schematic view showing a medical sheet according to the present invention. Fig. 1 (a) shows the first surface, and Fig. 1 (b) shows the second surface. The roughened portion 3 means a portion having a rougher surface than the second surface. The roughened portion 3 may be a portion modified by ion impact. The roughened portion 3 may be the entirety of the first surface 5 or a specific portion of the first surface. When it is desired to roughen only a specific part of the first surface, for example, the roughening process may be performed in a state of covering a part that is not roughened. Roughened part 3 series: The Rz value as the surface roughness value is 8 or more and 14 or less (preferably 9 or more or 13 or less, or 9.5 or more and 12.5 or less or 10 or more and 12 or less), and the Ra value may be 0.65 or more and 1.5 or less. The following (preferably 0.7 or more and 1.4 or less, or 0.8 or more and 1.3 or less). These values may be obtained in accordance with JIS B 0601-2001.

By performing a heat treatment on a medical sheet having surface roughness like this, the degree of discoloration of the roughened portion and the non-roughened portion is different, so that a roughened portion and a non-roughened portion can be obtained. Medical sheet. As described later, when a vascular prosthesis is produced using a medical sheet having the above-mentioned roughness, the vascular endothelial cell is easily fixed.

The medical sheet is preferably a portion where the roughened portion and the non-roughened portion can be visually determined based on the difference in hue.

The Lab color measurement method can be obtained by the following formula using tristimulus values X, Y, and Z specified in JIS Z8730.

L = 10Y ^1/2 ... (1) a = 17.5 (1.02X-Y) / Y ^1/2 ... (2) b = 7.0 (Y-0.847Z) / Y ^1/2 ... (3) L: Hunt (RS Hunter) The lightness index in the color difference formula. a, b: The color coordinates in Henry's characteristic difference. X, Y, Z: Tristimulus values X, Y, and Z in the X, Y, and Z color expressions.

In the Lab color measurement method, L represents lightness, and is generally a value of 100 to 0. Lightness refers to the lightness and darkness of the color, that is, the degree of brightness. A larger L value means brighter.

In addition, a and b indicate colors, a value indicates a red-green direction, and b value indicates a yellow-blue direction. Therefore, the larger the value of a, the stronger the red phase, and the smaller the value, the stronger the green phase; the larger the b value, the stronger the yellow phase, and the smaller the value, the stronger the blue phase.

Subsequently, this sheet-based medical: _{b. 1} is provided as a difference value b value b as the portion 3 and the value of the second surface 7 of the _second value when graining b Δb, Δb is 2 or more 11 or less. Δb can generally be obtained from the value of b ₁ -b ₂ . Δb may be 4 or more and 10 or less, Δb may be 5 or more and 9.5 or less, Δb may be 6 or more and 9.5 or less, Δb may be 6 or more and 9 or less, and Δb may be 7 or more and 8.5 or less. Since the roughened portion of the medical sheet of the present invention has a yellow phase as described above, it is possible to distinguish a surface having a roughened portion from a surface having no roughened portion (in addition, both surfaces may have Part of the roughened part can be judged as a roughened part by the hue of the roughened part).

This medical sheet can also distinguish the roughened portion by showing a color with a slight reddish tint. In particular, under a yellow fluorescent lamp, in order to discriminate a roughened portion, a hue with a red tint and a hue with a green tint can be distinguished. The conventional medical sheet has a slight green hue. In contrast, the medical sheet of the present invention has a slightly reddish color. In this medical sheet system, when the difference between the a ₁ value which is the a value of the roughened portion 3 and the a ₂ value which is the a value of the second surface 7 is Δa, Δa is preferably 0.1 or more and 1 or less. Δa can generally be obtained from the value of a ₁ -a ₂ . Δa may be 0.15 or more and 0.9 or less, and Δa may be 0.2 or more and 0.5 or less.

An example of polytetrafluoroethylene is stretched polytetrafluoroethylene (ePTFE). Examples of stretched polytetrafluoroethylene are stretched porous polytetrafluoroethylene produced according to U.S. Patent Nos. 3953566 and 4187390. Furthermore, in the examples, experiments were performed using stretched polytetrafluoroethylene in principle. In contrast, the effects confirmed in the examples can be inferred that polytetrafluoroethylene-based sheets are generally effective.

Next, the present invention relates to a method for manufacturing a medical sheet. This method includes a roughening step of roughening all or part of the first surface 5 of a sheet containing polytetrafluoroethylene to form a roughened portion 3. Next, in the roughening step, ion impact is continuously performed in a vacuum degree of 10 ^-7 pressure or more and 10 ^-1 pressure or less. The method may further include a heating step of heating the polytetrafluoroethylene-containing sheet after the roughening step to obtain a medical sheet. Conventionally, the surface of the sheet is washed with an organic solvent. However, if the surface of the sheet is washed with an organic solvent, the organic solvent remains on the surface of the sheet, and the compound derived from the organic solvent adheres to the surface of the sheet. Therefore, in the present invention, it is preferable to perform cutting of the sheet or roughening of the sheet in a clean room without cleaning the surface of the sheet with an organic solvent. The ion impact is preferably performed continuously in a vacuum chamber as described later.

The roughening treatment in the roughening step is, for example, ion implantation (ion impact), plasma treatment, corona treatment, UV treatment, chemical blasting, and sand blasting. In this manufacturing method, the roughened portion 3 has an Rz value of 8 or more and 14 or less, and a Ra value of 0.65 or more and 1.5 or less. That is, it is preferable to perform the subsequent processing steps in a state where the surface is slightly roughened compared to the conventional medical sheet. With regard to ion implantation, for example, by keeping the degree of vacuum in the vacuum chamber (inside the ion impact device) during ion impact within a certain range under the conventional ion implantation method, the ion impact is continuously performed, and the x-axis direction and y are controlled. The amount of ion collision in the axial direction can further achieve better surface roughness. The ion density (implantation amount φ) is, for example, 1 × 10 ¹³ ions / cm ² or more and 1 × 10 ¹⁶ ions / cm ² or less, and may be 1 × 10 ¹⁴ ions / cm ² or more and 1 × 10 ¹⁵ ions / cm ² or less. The acceleration voltage of the ions is, for example, from 30 keV to 2000 keV, or from 70 keV to 300 keV, or from 100 keV to 250 keV. The ion irradiation time is, for example, from 1 minute to 5 hours, or from 10 minutes to 2 hours, or from 30 minutes to 1 hour.

The degree of vacuum in the chamber is, for example, 10 ^-7 atmospheres or more and 10 ^-1 atmospheres or less, or 10 ^-6 atmospheres or more and 10 ^-2 atmospheres or less, or 10 ^-5 atmospheres or more and 5 × 10 ^-3 atmospheres or less. It is ^10-4 atmospheres or more and ^10-3 atmospheres or less. The vacuum system itself is well known. By using a vacuum system having a vacuum chamber and a pump connected to the vacuum chamber, the required degree of vacuum can be achieved. The ion collision can be performed continuously by performing ion collision while appropriately performing exhaust. It can be inferred that good surface roughness can be achieved by this. The ion irradiation amount is preferably controlled so that the x-axis direction is uniformly the same as the y-axis direction. For this reason, it is only necessary to control the position or direction of the nozzle for ion irradiation. In this way, a good surface roughness can be achieved. For example, after controlling the surface roughness in such a state, heat treatment can be used to make the medical sheet more yellowish.

The surface modification of PTFE is, for example, a method of introducing functional groups or surface etching on the surface of a substrate by using O ₂ or Ar gas; and a plasma polymerization method of polymerizing an organic monomer under a plasma to form a thin film on the surface of the substrate. .

The heating step may be a step of heating the sheet at a temperature of 60 ° C. to 300 ° C. for 10 seconds to 1 hour. The heating temperature may be, for example, 60 ° C or higher and 150 ° C or lower, or 100 ° C or higher and 130 ° C or lower. In particular, when ethylene oxide gas (EOG) sterilization is performed, the temperature may be 60 ° C or higher and 100 ° C or lower, or 65 ° C or higher and 80 ° C or lower. The heating temperature may be 110 ° C or higher and 140 ° C or lower, or may be 110 ° C or higher and 130 ° C or lower. The heating time may be adjusted appropriately in accordance with the heating temperature, and may be 10 minutes to 45 minutes, 15 minutes to 30 minutes, 20 seconds to 5 minutes, or 40 seconds to 2 minutes. Is preferably in a manner as described later heating sheet: After cooling the sheet after the heating step, a set value b _{value. 1} b roughened portion 3 and a value of b bits in the second face of the first face 7 opposite to the side 5 When the difference in b ₂ value is Δb, Δb is 2 or more and 11 or less.

[Example 1]

In a clean room, GORE-TEX (registered trademark) of ePTFE manufactured by Gore was cut into 10.0 cm x 10.0 cm to obtain ePTFE sheets. The surface of the ePTFE sheet was not washed with an organic solvent, and an ion impact was applied to the ePTFE sheet using an ion implantation device to modify the surface. The conditions for ion collision are as follows.

Ion: Ar ⁺

Energy: 150keV

Ion density: 5 × 10 ¹⁴ ions / cm ²

During the ion collision, the degree of vacuum in the ion implantation apparatus is maintained at 10 ^-5 atmospheres or more and 10 ^-4 atmospheres or less. In addition, the amount of irradiation of ions was adjusted so that the x-axis direction and the y-axis direction of the ions collided uniformly.

The surface-modified ePTFE sheet was heat-treated in an autoclave (120 ° C) for 20 minutes. Next, the ePTFE sheet was left to stand until the temperature after heating in the autoclave became normal temperature. Thus, a medical sheet was obtained.

[Comparative Example 1]

A medical sheet was obtained in the same manner as in Example 1 except that heating was not performed in an autoclave (Comparative Example 1).

The surface roughness of the obtained medical sheet was measured. The surface roughness was a 3D measuring laser microscope OLYMPUS OLS4000 made by Olympus. The results obtained are shown in Table 1.

[Table 1]

The hue of the obtained medical sheet was measured. The color tone was measured using a spectrophotometer made by Konica Minolta. The results obtained are shown in Table 2.

[Table 2]

As a result of visual observation, the portion to which ion impact was applied was significantly yellower than the sheet of Comparative Example 1, and it was in a state where the presence or absence of ion impact was clearly distinguished.

[Example 2] A medical sheet was obtained in the same manner as in Example 1 except that the temperature of the autoclave was set to 130 ° C.

[Example 3] A medical sheet was obtained in the same manner as in Example 1 except that the time of the autoclave was set to 3 minutes.

[Example 4] A medical sheet was obtained in the same manner as in Example 1 except that the PTFE sheet was used instead of the ePTFE sheet.

[Example 5] A medical sheet was obtained in the same manner as in Example 1 except that the roughening treatment section was partially used.

[Example 6] A medical sheet was obtained in the same manner as in Example 1 except that blasting was used instead of ion implantation.

[Example 7] A medical sheet was obtained in the same manner as in Example 1, except that ion implantation was used instead of ion implantation.

[Example 8] A medical sheet was obtained in the same manner as in Example 1 except that the autoclave was replaced with EOG sterilization at 70 ° C.

[Example 9] A medical sheet was obtained in the same manner as in Example 1 except that POREFLON (registered trademark) manufactured by Sumitomo Electric Industries was used instead of GORE-TEX (registered trademark) manufactured by Gore.

Although the flakes of Examples 2 to 7 and 9 are similar to the flakes of Example 1 with a yellow tint, the flakes of Example 1 are most obvious in yellow and can clearly grasp the presence or absence of processing. In comparison with the sheet of Comparative Example 1, the sheet of Example 8 has a slight yellow tint, and the presence or absence of treatment can be grasped by careful observation. In addition, the same experiment was performed after changing the ion impact conditions in Example 1 multiple times, and the results obtained showed the same tendency as in Examples 1 to 9 and Comparative Example 1.

[Comparative Example 1] A medical sheet is produced in accordance with the example of Japanese Patent No. 4445697 according to the actual conditions. The surface of the stretched polytetrafluoroethylene (ePTFE) was washed with an organic solvent. Then, an ion beam (Ne ⁺ , 150 keV, 5 × 10 ¹⁴ ions / cm ² ) was irradiated at 200 keV. Since the degree of vacuum decreases each time an ion impact is performed, the operation of exhausting the ion impact and stopping the ion impact repeatedly is performed. In addition, the directional plane of the ion collision is not uniformly adjusted. The hue of the obtained medical sheet was measured. The color tone was measured using a spectrophotometer made by Konica Minolta.

The surface roughness of the medical sheet obtained in Comparative Example 1 was based on an average Rz value of 5 (standard deviation of 0.5) and an average value of Ra of 0.52 (standard deviation of 0.05). This sheet system cannot distinguish the hue of the surface on which the ion beam is irradiated and the surface on which it is not irradiated. The average value of b of the roughened portion of this sheet can be estimated to be a negative value.

[Example 10] The medical sheet obtained in Comparative Example 1 was heat-treated in an autoclave (120 ° C) for 20 minutes. Next, the ePTFE sheet was left to stand until the temperature after heating in the autoclave became normal temperature. Thus, a medical sheet was obtained. As a result of visual observation, the portion to which the ion impact was applied was slightly more recognizable than the sheet tape of Comparative Example 1. The b value of this sheet is 2 to 3.

Using the sheets of the above examples, comparative examples, and comparative examples, artificial blood vessels (medical catheters) having an inner diameter of 4 mm and 6 mm were prepared. Next, observe the coagulation component of the blood under the whole blood of the human vascular prosthesis produced for 1, 2, 4, 8, 24, and 48 hours. As a result, the blood vessel of Example 1 formed a thrombus very early, and the vascular endothelial cells were fixed on this thrombus, so it was a good artificial blood vessel. In contrast, although the blood vessel of Comparative Example 1 had no blood leakage and could function as a vascular prosthesis, it took a long time until the blood vessel endothelial cells became fixed. The blood vessels of the other examples or comparative examples have the performances between those of Example 1 and Comparative Example 1.

[Industrial Applicability] The present invention can be used in the field of medical equipment.

1‧‧‧ medical sheet

3‧‧‧ Roughening Department

5‧‧‧ the first side

7‧‧‧ second side

FIG. 1 is a schematic view showing a medical sheet according to the present invention. Fig. 1 (a) shows the first surface, and Fig. 1 (b) shows the second surface.

Claims (6)

A medical sheet (1) containing polytetrafluoroethylene and comprising: a first surface (5) having a roughened portion; and a second surface (7) on the opposite side of the first surface (5), wherein, The roughened portion (3) is an Rz value of 8 or more and 14 or less and a Ra value of 0.65 or more and 1.5 or less; and a value of b _{1 as} a b value of the roughened portion (3). When the difference from the b ₂ value which is the b value of the second surface (7) is Δb, Δb is 2 or more and 11 or less. The medical sheet according to item 1 of the scope of patent application, wherein the roughened portion (3) is a portion modified by ion impact. The medical sheet according to item 1 of the scope of patent application, wherein the roughened portion (3) is a part of the first surface (5). A method for manufacturing a medical sheet, including a roughening step of forming a roughened portion of all or part of a first surface (5) of a sheet containing polytetrafluoroethylene by ion impact. (3), wherein the ion impact is continuously performed in a vacuum of 10 ^-7 or more and 10 ^-1 or less; and further includes a heating step of heating the polytetrafluoroethylene-containing To obtain a medical sheet, wherein in the heating step, a difference between a b ₁ value that is a b value of the roughened portion (3) and a b ₂ value that is a b value of the second surface (7) is In the case of Δb, heating is performed so that Δb is 2 or more and 11 or less. The method for manufacturing a medical sheet according to item 4 of the scope of patent application, wherein the roughened portion (3) is a surface roughness value of Rz value of 8 or more and 14 or less, and Ra value of 0.65 or more and 1.5. the following. The method for manufacturing a medical sheet according to item 4 of the scope of patent application, wherein the heating step is a step of heating the sheet at a temperature of 60 ° C. to 300 ° C. for 10 seconds to 10 minutes.