Resin composition, resin molded product, and medical procedure practice sheet

Abstract

The present invention provides resin molded products having flexibility and toughness, sheets for practicing medical procedures, and resin compositions used in their manufacture. [Solution] The resin molded product 1 is made of silica-containing silicone rubber, and contains 10 parts by mass or less of silica per 100 parts by mass of silicone rubber. The resin molded product 1 is in the shape of a rectangular sheet (rectangular plate) and is used, for example, as a medical procedure practice sheet for practicing medical procedures such as incision, suturing and puncture.

Description

Technical Field

[0001] The present invention relates to a resin composition, a resin molded article, and a sheet for medical procedure practice.

Background Art

[0002] Silicone rubber is used in a wide variety of products, and is also used, for example, in biological models for practicing medical procedures such as incision, suturing, and puncture.

[0003] In order to enhance the effect of procedure practice, the biological model is preferably as close as possible to each part of the human body. For example, skin models are required to have softness (low hardness) close to that of human skin and fascia, and to have toughness that prevents cuts from extending beyond the length of the part where a scalpel is inserted for incision, and prevents tearing of the part where a needle is passed through for suturing the incised portion.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, conventional skin models made of silicone rubber at least do not have softness close to that of human skin or the like, or do not have toughness suitable for procedures.

[0006] An object of the present invention is to provide a resin molded article and a sheet for medical procedure practice that have softness and toughness, as well as a resin composition used for producing the resin molded article.

Means for Solving the Problems

[0007] To achieve the above objective, the resin composition according to one aspect of the present invention contains 10 parts by mass or less of silica per 100 parts by mass of silicone rubber.

[0008] The silicone rubber may be liquid silicone rubber. In that case, silica can be easily mixed into the liquid silicone rubber before curing.

[0009] The silicone rubber may be a one-component liquid silicone rubber or a two-component liquid silicone rubber. If the silicone rubber is a two-component liquid silicone rubber, the resin composition may contain a silicone rubber main component and a curing agent to be mixed with the main component, and may contain 10 parts by mass or less of silica per 100 parts by mass of the main component and curing agent combined, or it may contain a silicone rubber main component and a curing agent to be mixed with the main component, and the main component may contain 10 parts by mass or less of silica per 50 parts by mass of the main component. In the latter case, by adding 50 parts by mass of curing agent to a main component containing 10 parts by mass or less of silica per 50 parts by mass of the main component, a resin composition containing 10 parts by mass or less of silica per 100 parts by mass of the main component and curing agent combined can be obtained.

[0010] By curing the aforementioned resin composition, a resin molded article containing 10 parts by mass or less of silica per 100 parts by mass of silicone rubber can be obtained. This resin molded article has flexibility and toughness due to the inclusion of 10 parts by mass or less of silica per 100 parts by mass of silicone rubber.

[0011] Therefore, if a resin molded product made from the aforementioned resin composition is formed into a sheet, the sheet-shaped resin molded product can be used as a sheet for practicing medical procedures such as incision, suturing, and puncture. Such a medical procedure practice sheet has a softness (low hardness) similar to that of human skin and fascia. Furthermore, the medical procedure practice sheet has toughness such that the cut does not extend beyond the length of the part where the scalpel is used for incision, and the part where the needle is passed to suture the incised area does not tear. [Effects of the Invention]

[0012] According to the present invention, it is possible to obtain a resin molded product having flexibility and toughness, such as a medical procedure practice sheet that has flexibility similar to human skin or fascia, and toughness such that the cut does not extend beyond the length of the part where the scalpel is made for incision, and the part through which the needle is passed for suturing the incised part does not tear. [Brief explanation of the drawing]

[0013] [Figure 1] This is a plan view of a resin molded product according to one embodiment of the present invention. [Figure 2] This is a plan view showing a resin molded product stretched in the longitudinal direction. [Figure 3] This graph shows the relationship between the displacement of the test specimen and the tensile force in Example 1. [Figure 4] This graph shows the relationship between the displacement of the test specimen and the tensile force in Example 2. [Figure 5] This graph shows the relationship between the displacement of the test specimen and the tensile force in Example 3. [Figure 6] This graph shows the relationship between the displacement of the test specimen and the tensile force in Example 4. [Figure 7] This graph shows the relationship between the displacement of the test specimen and the tensile force in the comparative example. [Modes for carrying out the invention]

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0015] <Resin molded products> Figure 1 is a plan view of a resin molded product 1 according to one embodiment of the present invention.

[0016] The resin molded product 1 is a molded product of silicone rubber containing silica. The resin molded product 1 is in the shape of a rectangular sheet (rectangular plate).

[0017] Figure 2 is a plan view showing a state where the resin molded article 1 is pulled in the longitudinal direction.

[0018] The resin molded article 1 has flexibility to elongate when pulled, and also has toughness that prevents it from being easily broken. The resin molded article 1 can be used, for example, as a sheet for medical procedure practice, for practicing procedures such as incision, suture, and puncture in medical care. The resin molded article 1 as a sheet for medical procedure practice has flexibility (low hardness) close to that of human skin and fascia, while possessing toughness that prevents the cut from extending beyond the length of the part where a scalpel is inserted for incision, and prevents the part where a needle is passed through for suturing the incised portion from tearing.

[0019] <Resin Composition> The resin composition used for producing the resin molded article 1 contains silicone rubber and silica (SiO₂: silicon dioxide).

[0020] The silicone rubber may be a liquid silicone rubber, or may be a millable type silicone rubber (solid silicone rubber). The liquid silicone rubber may be a one-part liquid silicone rubber, or may be a two-part liquid silicone rubber.

[0021] Examples of the one-part silicone rubber include the product name "KE-4895" manufactured by Shin-Etsu Chemical Co., Ltd.

[0022] As the two-part liquid silicone rubber, a two-part RTV (Room Temperature Vulcanizing) liquid silicone rubber can be suitably used, and examples thereof include the product names "ELASTOSIL (registered trademark) P7600" and "ELASTOSIL (registered trademark) P7684 / 60" manufactured by Asahi Kasei Wacker Silicone Co., Ltd.

[0023] Examples of the millable type silicone rubber include the product name "X-30-2873-U" manufactured by Shin-Etsu Chemical Co., Ltd.

[0024] However, if high flexibility (low hardness) is required for the resin molded product 1, the silicone rubber is preferably liquid silicone rubber.

[0025] The silica is dry silica. An example of dry silica is "AEROSIL® RY200" manufactured by Nippon Aerosil Co., Ltd. The silica content is 10 parts by mass or less per 100 parts by mass of silicone rubber.

[0026] <Manufacturing of resin molded products> The method for manufacturing a resin molded product will be explained using the case where the silicone rubber is a two-part liquid silicone rubber as an example.

[0027] For the manufacture of resin molded product 1, a two-component liquid silicone rubber main component and curing agent, and silica powder (silicic acid powder) are prepared.

[0028] First, the main component of the two-component liquid silicone rubber is placed in a container, then silica powder is added to the main component in the container, and the main component and silica powder are mixed by stirring. When using, for example, Asahi Kasei Wacker Silicone Co., Ltd.'s product "ELASTOSIL® P7600" or "ELASTOSIL® P7684 / 60" as the two-component liquid silicone rubber, the amount of silica powder is set to 10 parts by mass or less of silica per 50 parts by mass of the main component.

[0029] Next, a curing agent for two-component liquid silicone rubber is added to the mixture of the main component and silica powder in the container. When using, for example, "ELASTOSIL® P7600" or "ELASTOSIL® P7684 / 60" manufactured by Asahi Kasei Wacker Silicone Co., Ltd. as the two-component liquid silicone rubber, the amount of curing agent is set to 50 parts by mass of curing agent for every 50 parts by mass of main component.

[0030] Then, the mixed materials in the container are stirred using a stirrer, such as a rotary-orbiting stirrer (for example, model "ARE-500" manufactured by Thinky Co., Ltd.). This yields liquid silicone rubber in which silica powder is dispersed (hereinafter referred to as "pre-curing silicone rubber"). When a stirrer is used, it is preferable that after the stirring operation, a defoaming operation is performed in the stirrer to remove gas from the pre-curing liquid silicone rubber.

[0031] Subsequently, the uncured silicone rubber is injected into a mold. The mold containing the uncured silicone rubber is then left at room temperature for a certain period of time or longer, allowing the uncured silicone rubber inside the mold to harden. After the uncured silicone rubber has hardened, for example, the hardened silicone rubber, i.e., the resin molded product 1, is removed from the mold. The resin molded product 1 thus obtained contains 10 parts by mass or less of silica per 100 parts by mass of silicone rubber.

[0032] <Effects and Effects> As described above, the resin molded product 1 is made of silica-containing silicone rubber, and contains 10 parts by mass or less of silica per 100 parts by mass of silicone rubber. As a result, the resin molded product 1 has the softness (low hardness) and toughness required for a medical procedure practice sheet, and can be suitably used as a medical procedure practice sheet for practicing medical procedures such as incision, suturing, and puncture. In other words, the resin molded product 1 can be suitably used as a medical procedure practice sheet, and while it has softness similar to human skin and fascia, it has toughness that prevents the cut from extending beyond the length of the part where the scalpel is inserted for incision, and prevents the part where the needle is passed through for suturing from tearing.

[0033] <Variation> Although one embodiment of the present invention has been described above, the present invention can also be implemented in other forms.

[0034] For example, in the embodiment described above, the resin molded product 1 was formed in the shape of a rectangular sheet and could be used, for example, as a sheet for practicing medical procedures. The resin molded product according to the present invention is not limited to a rectangular sheet shape, and various shapes can be adopted depending on its application. Furthermore, the resin composition according to the present invention is suitable as a material for products that require flexibility and toughness. Examples of such products include medical procedure practice models other than medical procedure practice sheets (biological models such as artificial gums), joint supports for living bodies, fitness equipment such as rubber tubes, nursing care products for weight distribution such as pads that can be attached to handrails and toilet seat covers that can be attached to toilet seats, underwear such as nipple covers, adhesive bras and breast pads, hygiene products such as masks, bandages and wound dressings, and ear protection pads that can be attached to the straps of masks or the temples of eyeglasses.

[0035] Furthermore, the resin composition and resin molded articles according to the present invention may contain conductive powder, silicone oil, or the like, in addition to silica. If the resin molded article contains conductive powder, for example, if the resin molded article is a model for practicing medical procedures, its conductivity can be used to detect when an injection needle has penetrated a blood vessel wall.

[0036] Furthermore, various design modifications can be made to the aforementioned configuration within the scope of the matters described in the patent claims. [Examples]

[0037] Next, the present invention will be described based on examples and comparative examples. However, the present invention is not limited to the following examples.

[0038] To obtain the test specimens for each example and comparative example, a 6 mm thick sheet of resin molded material was prepared according to the manufacturing method described above. The conditions for preparing the sheet of resin molded material were the same for all examples, except for the material. In each example, four rectangular test specimens were punched out (cut) from the sheet of resin molded material, while in the comparative example, two rectangular test specimens were punched out (cut) from the sheet of resin molded material. Each test specimen was 100 mm long and 5 mm wide. In each example and comparative example, the main component and curing agent of the two-component liquid silicone rubber were materials A and B of "ELASTOSIL® P7600" manufactured by Asahi Kasei Wacker Silicone Co., Ltd., respectively. In addition, in each example, "AEROSIL® RY200" manufactured by Nippon Aerosil Co., Ltd. was used as the silica powder.

[0039] <Example 1> A resin composition containing 3 parts by mass of silica per 100 parts by mass of silicone rubber was used to produce the resin molded products. Then, using a universal material testing machine, each test piece (Example) 1-1, 1-2, 1-3, and 1-4 was subjected to a tensile test in the longitudinal direction at a constant speed of 10 mm / min. In the tensile test, the maximum tensile force, maximum tensile stress, and maximum displacement until each test piece 1-1, 1-2, 1-3, and 1-4 fractured (separated) are shown in Table 1. Furthermore, Figure 3 shows a graph with the displacement of each test piece 1-1, 1-2, 1-3, and 1-4 on the horizontal axis and the tensile force applied to each test piece 1-1, 1-2, 1-3, and 1-4 on the vertical axis.

[0040] [Table 1]

[0041] <Example 2> A resin composition containing 5 parts by mass of silica per 100 parts by mass of silicone rubber was used to produce the resin molded products. Then, using a universal material testing machine, each test piece (Example) 2-1, 2-2, 2-3, and 2-4 was subjected to a tensile test in the longitudinal direction at a constant speed of 10 mm / min. In the tensile test, the maximum tensile force, maximum tensile stress, and maximum displacement until each test piece 2-1, 2-2, 2-3, and 2-4 fractured (separated) are shown in Table 2. Furthermore, Figure 4 shows a graph with the displacement of each test piece 2-1, 2-2, 2-3, and 2-4 on the horizontal axis and the tensile force applied to each test piece 2-1, 2-2, 2-3, and 2-4 on the vertical axis.

[0042] [Table 2]

[0043] <Example 3> A resin composition containing 7 parts by mass of silica per 100 parts by mass of silicone rubber was used to produce the resin molded products. Then, using a universal material testing machine, each test piece (Example) 3-1, 3-2, 3-3, and 3-4 was subjected to a tensile test in the longitudinal direction at a constant speed of 10 mm / min. In the tensile test, the maximum tensile force, maximum tensile stress, and maximum displacement until each test piece 3-1, 3-2, 3-3, and 3-4 fractured (separated) are shown in Table 3. Furthermore, Figure 5 shows a graph with the displacement of each test piece 3-1, 3-2, 3-3, and 3-4 on the horizontal axis and the tensile force applied to each test piece 3-1, 3-2, 3-3, and 3-4 on the vertical axis.

[0044] [Table 3]

[0045] <Example 4> For the production of the resin molded products, a resin composition containing 5 parts by mass of silica and 15 parts by mass of silicone oil per 100 parts by mass of silicone rubber was used. Then, using a universal material testing machine, each test piece (Example) 4-1, 4-2, 4-3, and 4-4 was subjected to a tensile test in the longitudinal direction at a constant speed of 10 mm / min. In the tensile test, the maximum tensile force, maximum tensile stress, and maximum displacement until each test piece 4-1, 4-2, 4-3, and 4-4 fractured (separated) are shown in Table 4. Furthermore, Figure 6 shows a graph with the displacement of each test piece 4-1, 4-2, 4-3, and 4-4 on the horizontal axis and the tensile force applied to each test piece 4-1, 4-2, 4-3, and 4-4 on the vertical axis.

[0046] [Table 4]

[0047] <Comparative Example> Silica-free silicone rubber was used to manufacture the resin molded products. Then, using a universal material testing machine, each test piece (comparative example) 1-1 and 1-2 were subjected to a tensile test in the longitudinal direction at a constant speed of 10 mm / min. In the tensile test, the maximum tensile force, maximum tensile stress, and maximum displacement until each test piece 1-1 and 1-2 fractured (separated) are shown in Table 5. Furthermore, Figure 7 shows a graph with the displacement of each test piece 1-1 and 1-2 on the horizontal axis and the tensile force applied to each test piece 1-1 and 1-2 on the vertical axis.

[0048] [Table 5]

[0049] From a comparison of Examples 1 to 4 with the comparative examples, it was confirmed that the test specimens 1-1, 1-2, 1-3, and 1-4 of Example 1, 2-1, 2-2, 2-3, and 2-4 of Example 2, 3-1, 3-2, 3-3, and 3-4 of Example 3, and 4-1, 4-2, 4-3, and 4-4 of Example 4 all showed larger maximum tensile force, maximum tensile stress, and maximum displacement compared to the test specimens 1-1 and 1-2 of the comparative examples, and were superior in terms of softness (low hardness) and toughness. [Explanation of Symbols]

[0050] 1: Resin molded product

Claims

1. A resin composition containing 10 parts by mass or less of silica per 100 parts by mass of silicone rubber.

2. The main component of silicone rubber, The main component includes a curing agent that is mixed with the main component, A resin composition containing 10 parts by mass or less of silica per 100 parts by mass of the main component and the curing agent combined.

3. The main component of silicone rubber, The main component includes a curing agent that is mixed with the main component, The main component contains silica, A resin composition wherein the silica content is 10 parts by mass or less per 50 parts by mass of the main component.

4. A resin molded article comprising the resin composition according to any one of claims 1 to 3.

5. A sheet used for practicing medical procedures, A sheet for practicing medical procedures, made of silicone rubber containing silica.

6. The medical procedure practice sheet according to claim 5, wherein the silica content is 10 parts by mass or less per 100 parts by mass of the silicone rubber.

Images