sealing member

Abstract

To provide a seal member capable of reducing an unpleasant sound in attachment or detachment.SOLUTION: According to one aspect of the present invention, there is provided a seal member 10 which is used while interposed between a first member and a second member. The seal member 10 is formed of silicone resin. The seal member 10 has a profile in which silicon, oxygen and carbon are selected out of elements detected through XPS depth-directional analysis of at least a part of an abutting part between the first member and second member and 100 atm.% in total of those elements is contained, wherein a modified layer of 80% or larger in ratio of oxygen atomic concentration is 500 nm or larger thick when a maximum value of the oxygen atomic concentration from an outermost surface to a point of 200 nm in depth is 100%, and the difference between the maximum value and the oxygen atomic concentration at a point of 1,000 nm in depth from the outermost surface is 5 atm.% or larger.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a sealing member.

Background Art

[0002] In machines, devices, containers, pipes, etc., a sealing member is used to prevent leakage of liquid or gas to the outside or to prevent intrusion of foreign matter from the outside. The sealing member is usually used by being interposed between two members to be connected, whereby the connection portion is sealed.

[0003] In the sealing member used for a movable part, an unpleasant sound may be generated when the connection part is attached and detached. Patent Document 1 discloses a food and drink container capable of eliminating an unpleasant sound when the lid is opened and closed by devising a rotating mechanism.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Since the above - mentioned Patent Document 1 aims to eliminate unpleasant sounds by a specific structure, it lacks versatility. Therefore, an object of the present invention is to provide a sealing member capable of reducing unpleasant sounds during attachment and detachment.

Means for Solving the Problems

[0006] The inventors of the present invention have found that by making the sealing member a silicone resin having a specific surface layer, unpleasant sounds during attachment and detachment can be reduced, and thus completed the present invention.

[0007] That is, according to the first aspect of the present invention, A sealing member used by being interposed between a first member and a second member, Formed from silicone resin, For at least a portion of the contact area between the first member and the second member, silicon, oxygen, and carbon were selected from the elements detected by XPS depth profiling, and in a profile where the sum of the atomic concentrations of these elements was set to 100 atomic%, The thickness of the modified layer is 500 nm or more such that the ratio of oxygen atom concentrations is 80% or more, when the maximum oxygen atom concentration from the outermost surface to a depth of 200 nm is taken as 100%, and A sealing member is provided in which the difference between the aforementioned maximum value and the oxygen atom concentration at a depth of 1000 nm from the outermost surface is 5 atomic percent or more.

[0008] In the first embodiment described above, the silicone resin may have a Shore hardness of 30 to 80 as measured by a Type A durometer.

[0009] In the first embodiment described above, the sealing member may be ring-shaped.

[0010] In the first embodiment described above, the sealing member may be used by being attached to a groove provided in one of the first member and the second member.

[0011] In the first embodiment described above, the first member may be a lid, and the second member may be a bottomed cylindrical body. [Effects of the Invention]

[0012] According to the present invention, a sealing member that can reduce unpleasant noises during attachment and detachment can be provided. [Brief explanation of the drawing]

[0013] [Figure 1] Figures 1(a) and 1(b) are a schematic plan view of the sealing member according to Embodiment 1 and a cross-sectional view of the sealing member shown in Figure 1(a) along the line A-A', respectively. [Figure 2]Figs. 2(a) and (b) are, respectively, an exploded perspective view showing an overview of the sealed container according to Embodiment 1 as viewed from the lid side, and a perspective view showing an overview of the lid as viewed from the opening direction. [Figure 3] Fig. 3 is a cross-sectional view of the sealed container according to Embodiment 1. [Figure 4] Figs. 4(a) and (b) are, respectively, a plan view showing an overview of the seal member according to Embodiment 2, and a cross-sectional view taken along line B-B' of the seal member shown in Fig. 4(a). [Figure 5] Figs. 5(a) and (b) are, respectively, an exploded perspective view and a cross-sectional view showing an overview of the connecting pipe body according to Embodiment 2. [Figure 6] Fig. 6 is a diagram showing the results of the profile of the XPS depth-direction analysis for each sample. [Figure 7] Fig. 7 is a diagram showing the average value of the maximum volume during the attachment / detachment operation of the connection part for each sample.

Embodiments for Carrying Out the Invention

[0014] Hereinafter, the present invention will be described in detail.

[0015] Hereinafter, when a plurality of upper limit values and a plurality of lower limit values are separately described, it is assumed that all numerical ranges that can be freely combined and set from these upper limit values and lower limit values are described. Hereinafter, unless otherwise specified, it is assumed that various measurements were carried out with the environmental temperature being room temperature (for example, 25°C).

[0016] Hereinafter, the present invention will be described in detail with reference to the drawings. In the drawings referred to below, components having substantially the same function are denoted by the same reference numerals, and the description thereof may be omitted. Note that the dimensional ratios of the drawings cited in the following embodiments are exaggerated for the convenience of explanation and may be different from the actual ratios. Also, the drawings cited in the following embodiments are shown with simplification or schematization of the configuration or omission of some components for the convenience of explanation.

[0017] (Embodiment 1) Figure 1 shows a sealing member according to Embodiment 1. Figure 1(a) is a schematic plan view of the sealing member. Figure 1(b) is a cross-sectional view of the sealing member shown in Figure 1(a) along the line A-A'. Figure 2 shows a sealed container according to Embodiment 1. Figure 2(a) is an exploded perspective view of the sealed container as seen from the lid side. Figure 2(b) is a perspective view of the lid as seen from the opening direction. Furthermore, Figure 3 is a cross-sectional view of the sealed container according to Embodiment 1.

[0018] As shown in Figure 1(a), the sealing member 10 according to this embodiment is a ring-shaped member with a rectangular cross-section. Here, the contact point 12 refers to the contact point with each member when the first member and the second member are connected via the sealing member 10. The contact point 12 is composed of a contact point 12a and a contact point 12b. The contact point 12a refers to the contact point with the first member (the lid 20 according to this embodiment), and the contact point 12b refers to the contact point with the second member (the bottomed cylindrical body 30 according to this embodiment).

[0019] The shape of the sealing member 10 is typically ring-shaped, as shown in Figure 1(a), but is not particularly limited as long as it can be interposed between two members to be connected. In addition to the ring shape, the sealing member 10 can also be disc-shaped, cylindrical, etc. When the sealing member 10 is ring-shaped, as shown in Figures 2(b) and 3, it can be fixed to a groove in one of the members to be connected (in this embodiment, the groove 28 of the lid 20), making it easy to attach and detach the members. Therefore, it is preferable that the sealing member 10 according to this embodiment be attached to a groove provided in the first member or the second member. Conversely, the same effect can be obtained by providing a groove in a part of the sealing member 10 and fixing it by fitting a protrusion provided in the first member or the second member into it.

[0020] In this embodiment, the sealing member 10 preferably has a compressibility (crushing rate; JIS B 2401-2) of 0.1% or more and 30% or less when loaded (when the connection of the connection part is completed). Using a sealing member 10 with such a compressibility allows the connection part to be sealed, but unpleasant noise may be generated when attaching or detaching the connection part. In this embodiment, the compressibility of the sealing member 10 when loaded may preferably be 1% or more, 5% or more, or 8% or more. In addition, the compressibility of the sealing member 10 when loaded may preferably be 25% or less, 20% or less, 15% or less, or 10% or less. By using a sealing member 10 with such a compressibility, the connection part can be reliably sealed.

[0021] As shown in Figure 2, the sealed container 40 according to this embodiment comprises a sealing member 10, a lid 20, and a bottomed cylindrical body 30. In this embodiment, the lid 20 is shaped like a lidded cylindrical body and opens downwards, and consists of a lid top surface portion 22 and a lid side portion 24 connected to the lid top surface portion 22. A female screw portion 26 is provided on the inner circumference of the lid side portion 24. Furthermore, a groove portion 28 is provided on the inner circumference of the lid side portion 24 near the lid top surface portion 22. The bottomed cylindrical body 30 is a frustoconical bottomed cylindrical body with a larger diameter at the top and opens upwards, and consists of a cylindrical bottom surface portion 32 and a cylindrical side portion 34 connected to the cylindrical bottom surface portion 32. Near the opening of the cylindrical side portion 34, there is a cylindrical mouth portion 36. The mouth portion 36 has a male screw portion 38 on its outer circumference.

[0022] In this embodiment, the sealing member 10 is used in the sealed container 40, as shown in Figures 2(a) and 3. That is, in this embodiment, the sealing member 10 is a sealing member used interposed between the lid 20 (first member) and the bottomed cylindrical body 30 (second member).

[0023] In this embodiment, as shown in Figure 3, the lid 20 and the bottomed cylindrical body 30 are detachably connected by screwing together the female threaded portion 26 of the lid 20 and the male threaded portion 38 of the bottomed cylindrical body 30. Furthermore, in this embodiment, as shown in Figure 3, when the lid 20 is firmly connected to the bottomed cylindrical body 30, the contact portion 12a of the lid 20 is in close contact with the groove 28, and the contact portion 12b of the bottomed cylindrical body 30 is in close contact with the upper surface of the mouth portion 36 of the bottomed cylindrical body 30. As a result, the connection portion is sealed and the internal space of the bottomed cylindrical body 30 is sealed. In this embodiment, the method of connecting the members is screwing, but it is not particularly limited as long as the lid 20 and the bottomed cylindrical body 30 are in contact with the sealing member 10 when connected. The sealing member 10 in this embodiment is preferably used in movable parts, and is especially preferably used in connection parts that are repeatedly attached and detached, as it reduces unpleasant noise during attachment and detachment operations. Therefore, the sealing member 10 in this embodiment may also be a packing member.

[0024] The sealing member 10 according to this embodiment is made of silicone resin. The silicone resin according to this embodiment is not particularly limited, and any silicone resin can be selected according to the purpose. Examples of raw materials for the silicone resin include peroxide crosslinked millable silicone rubber, addition crosslinked millable silicone rubber, addition-type liquid silicone rubber, and condensation crosslinked liquid silicone rubber. Furthermore, either a two-component type or a one-component type silicone resin may be used as the raw material. The curing method of the raw material is not particularly limited as long as it is possible to form the sealing member 10. The curing method may be, for example, room temperature curing or heating curing.

[0025] The Shore hardness measured by a Type A durometer of the silicone resin according to this embodiment is preferably 30 or higher, more preferably 40 or higher, even more preferably 50 or higher, and particularly preferably 60 or higher. Furthermore, the Shore hardness measured by a Type A durometer of the silicone resin according to this embodiment is preferably 80 or lower, and even more preferably 70 or lower. When the Shore hardness is within this range, the sealing member 10 has excellent airtightness and is more likely to reduce unpleasant noise when attaching and detaching the first member and the second member. The Shore hardness can be measured using a test piece of the sealing member 10 according to this embodiment by a method in accordance with JIS K 6253-3.

[0026] The sealing member 10 according to this embodiment has a modified layer on its surface layer. Specifically, in the sealing member 10, it is preferable that the thickness of the modified layer is 500 nm or more such that, in the profile obtained by X-ray photoelectron spectroscopy (XPS) depth profiling for at least a portion of the contact area 12 with the first member and the second member, the ratio of oxygen atom concentrations when the maximum oxygen atom concentration from the outermost surface to a depth of 200 nm is set to 100%, is 80% or more. Here, "profile obtained by XPS depth profiling" in this specification refers to a profile in which silicon (Si2p), oxygen (O1s), and carbon (C1s) are selected from the elements detected in the XPS depth profiling, and the sum of the concentrations of these atoms is set to 100 atomic percent. Each element can be quantified using the relative sensitivity coefficient method from the obtained peak area after determining the background using the Shirley method or Tougaard method, etc. Furthermore, the thickness of the modified layer according to this embodiment is more preferably 700 nm or more, and particularly preferably 1000 nm or more. The maximum value of the oxygen atom concentration from the outermost surface to a depth of 200 nm is not particularly limited, but is, for example, 40 atomic percent or more, preferably 50 atomic percent or more. By using a sealing member 10 having such a modified layer, unpleasant noises can be reduced when attaching and detaching the first member and the second member. The reason why unpleasant noises can be reduced during attachment and detachment is presumed to be that when a load is applied to the sealing member 10 by the attachment and detachment operation, the modified layer is less likely to compress and deform. Unpleasant noises during attachment and detachment are particularly likely to occur when a large load is applied to the sealing member 10. Therefore, they are more likely to occur when the compressibility of the sealing member 10 is high, for example, just before the connection of the connection part is completed or just after the start of the removal of the connection part.

[0027] Furthermore, in this embodiment, it is preferable that part or all of the contact area 12b of the contact area 12 has the modified layer described above, and it is particularly preferable that all of the contact area 12b has the modified layer described above. When all of the contact area has the modified layer, the modified layer defined by the index described above can be confirmed when XPS depth direction analysis is performed at any location. In this embodiment, since the seal member 10 is fixed by the groove 28, the contact area 12a is less likely to be subjected to load due to attachment and detachment operations. On the other hand, the unfixed contact area 12b is more susceptible to load due to attachment and detachment operations. As described above, unpleasant noises during attachment and detachment are more likely to occur when load is applied during attachment and detachment operations, so it is preferable that the modified layer described above be present in locations where load is easily applied during attachment and detachment operations. Therefore, in other words, in this embodiment, it is preferable that the seal member 10 has the modified layer described above in the unfixed locations of the contact area 12 with the first member and the second member. Here, "a portion of the contact area that is not fixed" can also be defined as "a portion of the contact area that slides against the first or second member during attachment / detachment operations."

[0028] In this embodiment, the seal member 10 is further preferably such that, in the profile obtained by XPS depth analysis for at least a portion of the contact area 12 with the first member and the second member, the difference between the maximum oxygen atom concentration from the outermost surface to a depth of 200 nm and the oxygen atom concentration at a depth of 1000 nm from the outermost surface is 5 atomic percent or more. Furthermore, it is preferable that the difference between this maximum value and the oxygen atom concentration at a depth of 2000 nm from the outermost surface is 7 atomic percent or more. By using a seal member 10 with such an oxygen atom concentration in the surface layer, unpleasant noise during attachment and detachment can be reduced. The reason why unpleasant noise during attachment and detachment can be reduced is presumed to be that, while having the modified layer which is resistant to compression deformation as described above, the surface layer has a gradient of oxygen atom concentration, allowing the seal member 10 as a whole to slide while maintaining minimal strain associated with the attachment and detachment operation. Therefore, it is preferable that the dynamic friction coefficient of the seal member 10 in this embodiment is small. The dynamic friction coefficient can be measured, for example, by a method in accordance with JIS K 7125. The coefficient of dynamic friction of the sealing member 10 according to this embodiment is preferably 0.25 or less, and more preferably 0.20 or less.

[0029] XPS analysis is an analytical technique that excites electrons with energies corresponding to energy levels within a solid by irradiating the sample surface with X-rays, and then measures the kinetic energy of the photoelectrons emitted into a vacuum. Since each orbital energy level of each element has a unique binding energy value, elemental analysis can be performed on the sample surface. Furthermore, by performing XPS analysis while removing material from the sample surface using ion sputtering, elemental analysis can be performed at a predetermined depth from the outermost surface. Ion sputtering can be performed, for example, by irradiation with an argon ion beam. The analysis unit depth for XPS depth profiling can be set arbitrarily. XPS depth profiling can be performed, for example, in increments of 10 nm, 100 nm, etc. As an XPS depth profiling analyzer, for example, the K-Alpha manufactured by Thermo Fisher Scientific can be used.

[0030] The material of the lid 20 and the bottomed cylindrical body 30 according to this embodiment is not particularly limited and can be made from any material. Examples of materials for the lid 20 and the bottomed cylindrical body 30 include plastic and metal. In addition, although the lid 20 and the bottomed cylindrical body 30 shown in Figure 3 are single components integrally molded from a single material, they may be made by combining multiple materials. Furthermore, the surface of the part that comes into contact with the sealing member 10 may be a mirror-finished surface that is prone to generating unpleasant noise. In particular, a metal mirror-finish surface of the part that comes into contact with the sealing member 10 is prone to generating unpleasant noise. By using the sealing member 10 according to this embodiment, unpleasant noise can be reduced even if such a surface is present.

[0031] Although the sealing member 10 according to this embodiment is used in a sealed container 40, it may also be used in an unsealed container having an opening on the top surface 22 of the lid, etc. The sealing member 10 according to this embodiment seals the connection between members, and whether or not the container itself is airtight can be arbitrarily selected depending on the intended use.

[0032] The use of the sealed container 40 according to this embodiment is not particularly limited. Unpleasant noise during attachment and detachment increases when liquid such as water adheres to the contact area 14, so the effects of this embodiment can be more fully enjoyed when used in situations where liquid may adhere. Therefore, the sealed container 40 according to this embodiment may be a food and beverage storage container, etc. The temperature of the contents contained in the food and beverage storage container, etc., is not particularly limited as long as it is within the performance range of the container itself, and may be low temperatures of 10°C or less, room temperature, or high temperatures of 80°C or more. Even if liquid contained in the contents at such temperatures (including water vapor generated from high-temperature contents, etc.) adheres to the contact area 12, the unpleasant noise during attachment and detachment can be reduced by using the sealing member 10 according to this embodiment.

[0033] The sealing member 10 according to this embodiment can be manufactured, for example, by irradiating molded silicone resin with UV light. The molding method for the silicone resin is not particularly limited, but examples include injection molding using molten silicone and a mold. The UV irradiation conditions can be appropriately changed depending on the type of silicone resin. By highly optimizing the wavelength of the irradiated light and the integrated light amount, a sealing member having the profile obtained by the XPS depth profiling analysis described above can be obtained. The sealing member according to this embodiment can be manufactured, for example, by irradiating molded silicone resin with ultraviolet light with a wavelength of 210 nm or less for 30 minutes or more. The wavelength of the ultraviolet light is preferably 200 nm or less, and more preferably 190 nm or less. The lower limit of the wavelength of the ultraviolet light is not particularly limited, but may be, for example, 10 nm, 100 nm, or 150 nm. The integrated light amount at the irradiation wavelength is, for example, 5000 mJ / cm². 2 The above is preferable, and 10,000 mJ / cm² is preferred. 2 It is even more preferable that the above conditions are met. The upper limit of the integrated light amount at the irradiation wavelength is not particularly limited, but for example, 100,000 mJ / cm 2 50,000 mJ / cm² 2 This may also be done. With such an integrated light intensity, damage to the sealing member itself (e.g., increase in compression set or cracks on the surface) hardly occurs, and a sealing member with a high sound-dampening effect can be obtained. Here, the compression set is a value that can be measured by a method in accordance with JIS K 6262, for example, with a test temperature of 180°C, a test time of 168 hours, and a compressibility of 25%. The compression set of the sealing member according to this embodiment obtained by UV irradiation is preferably 120% or less, and more preferably 115% or less, with respect to the sealing member before irradiation.

[0034] The reduction of unpleasant noise by the sealing member according to this embodiment can be detected by conventionally known methods. Specifically, the reduction can be detected by installing the sealing member 10 between the lid 20 and the bottomed cylindrical body 30, and measuring the sound volume during attachment and detachment operations with liquid adhering to the contact area 12. Any sound level meter can be used to measure the sound volume; for example, a precision sound level meter (NL-31; manufactured by Rion Co., Ltd.) can be used. When measuring the sound volume, it is preferable to use a windbreak screen or the like to eliminate noise in the measurement environment.

[0035] (Embodiment 2) Figure 4 shows a sealing member according to Embodiment 2. Figure 4(a) is a schematic plan view of the sealing member. Figure 4(b) is a cross-sectional view of the sealing member shown in Figure 4(a) along the line B-B'. Figure 5 shows a connecting pipe according to Embodiment 2. Figure 5(a) is an exploded perspective view showing the connecting pipe in general. Figure 5(b) is a cross-sectional view of the connecting pipe. The basic configuration of this embodiment is the same as that of Embodiment 1. The configurations that differ from Embodiment 1 will be described below.

[0036] As shown in Figure 4(a), the cross-sectional shape of the sealing member 10 according to this embodiment is circular, unlike that of Embodiment 1. Thus, the cross-sectional shape of the sealing member 10 is not particularly limited as long as it can function as a sealing member.

[0037] As shown in Figure 5, the connecting pipe body 70 according to this embodiment comprises a sealing member 10, a first pipe body 50 (the first member in this embodiment), and a second pipe body 60 (the second member in this embodiment). In this embodiment, the second pipe body 60 comprises a pipe body portion 61 and a receiving portion 62 into which the first pipe body 50 is inserted. A groove portion 64 is provided on the inner circumferential surface of the receiving portion 62. In Embodiment 1, a groove portion 28 for fixing the sealing member 10 was provided in the lid 20, which is the first member, but in Embodiment 2, a groove portion 64 for fixing the sealing member 10 is provided in the second pipe body 60, which is the second member. The groove portion for fixing the sealing member 10 is not an essential component of this embodiment, but as described above, it is preferable that it be provided in either the first member or the second member. Furthermore, in this embodiment, since the groove portion 64 is provided in the second member, it is preferable that some or all of the unfixed contact portions 12a of the contact portions 12 have the modified layer described above.

[0038] As shown in Figure 5, the sealing member 10 according to this embodiment is used to connect pipes together. That is, in this embodiment, the sealing member 10 is a sealing member used by being interposed between the first pipe 50 (first member) and the second pipe 60 (second member).

[0039] As shown in this embodiment, the first and second members may be pipes. The connecting pipe 70 in this embodiment may be, for example, a pipe or the like.

[0040] The present invention is not limited to the embodiments described above, and various modifications such as design changes can be made based on the knowledge of those skilled in the art, and such modified embodiments are also included within the scope of the present invention.

[0041] The sealing member according to this embodiment may be integrally molded with the first member or the second member. For example, a sealed container in which a sealing member, which also has a lid structure, is connected to a bottomed cylindrical body is also included in the scope of the present invention.

[0042] The sealing member according to this embodiment may be interposed between the first member (bottomed cylindrical body) and the second member (tube), or between the second member and the third member (lid), or both. A sealed container having such a first member, second member, and third member is also included in the scope of the present invention. [Examples]

[0043] (Sample preparation) An unmodified sealing member molded using addition-crosslinked millable silicone rubber was placed on a tray inside a UV irradiator (manufactured by Iwasaki Electric Co., Ltd.) and irradiated for a predetermined processing time under the following conditions. Under these conditions, the average irradiance at the irradiation wavelength was 3.3 mW / cm². 2 The integrated light dose at the irradiation wavelength is 1980 mJ / cm² per 10 minutes of irradiation. 2 This was confirmed using a light meter (manufactured by Hamamatsu Photonics). Irradiation wavelength: 185nm Irradiation distance: 6mm

[0044] (Analysis of the surface layer) XPS depth profiling was performed on each sample. Specifically, when the sample was used as a sealing material, a portion of the contact area (10 mm wide, 1 mm thick) that was not fixed in a groove, etc., was cut out and used as a test piece for XPS depth profiling. Subsequently, XPS depth profiling was performed on each test piece using an XPS depth profiling analyzer (K-Alpha; Thermo Fisher Scientific) under the following conditions. Excitation X-rays: Monochromatic Al Kα rays, irradiation diameter 400 μm, neutralization gun used. Pass energy: 200 eV Energy step: 1 eV Etching: Argon ion gun, 3kV Etching area: 2mm x 2mm Analysis depth: From the outermost surface to 4000 nm (in 100 nm increments)

[0045] Figure 6 shows the results of the XPS depth profile analysis for each sample. From Figure 6, it can be seen that the oxygen atom concentration near the outermost surface increases with processing time compared to the surface layer of the untreated sample. Table 1 shows (1) the thickness of the modified layer (from the point where the ratio of oxygen atom concentration is 80% or more, with the maximum oxygen atom concentration from the outermost surface to a depth of 200 nm being 100%) and (2) the difference between the maximum oxygen atom concentration from the outermost surface to a depth of 200 nm and the oxygen atom concentration at a predetermined depth from the outermost surface for each sample.

[0046] [Table 1]

[0047] In Table 1, the thickness of the modified layer was greater than or equal to the analysis depth (4000 nm) in both the untreated and 20-minute treated samples. However, this is an apparent value calculated using a defined method. If the material is not modified or is only slightly modified, as shown in Figure 6, the maximum oxygen atom concentration from the outermost surface to a depth of 200 nm is low, and the difference from the oxygen atom concentration of the unmodified layer is less than 20%. In other words, the presence or absence of modification cannot be determined by this calculation method alone. Therefore, the sealing member according to this embodiment must also satisfy the indicator (2) that shows that there is a gradient in oxygen atom concentration in the surface layer.

[0048] (Shore hardness) Shore hardness was measured for untreated and 70-minute treated samples using a Type A durometer (DigiTest; H. Barleys). Each sample was measured five times, and the average value was calculated. The Shore hardness results for each sample are shown in Table 2.

[0049] [Table 2]

[0050] (Sound level measurement) A sealed container was prepared, similar to the configuration shown in Figure 1, connected to each sample via a sealing member. The sealed container consists of a lid and a bottomed cylinder connected by screws, and the lid has a groove for fixing the sealing member. The materials of the contact points between the lid and the sealing member are plastic and stainless steel, respectively.

[0051] First, each sample was fixed in the groove of the lid. Next, approximately half the volume of room temperature water or hot water at about 90°C was poured into the bottomed cylindrical container, and then the lid was attached to seal the container. At this time, the compression ratio of the sample was 9%. Furthermore, the sealed container was shaken to wet the connection point.

[0052] The connection and disconnection operation was repeated five times, and the maximum sound volume at that time was measured using a precision sound level meter (NL-31; manufactured by Rion Co., Ltd.) equipped with a windproof screen (WS-10; manufactured by Rion Co., Ltd.) (n=2). Furthermore, the level of noise discomfort at that time was evaluated according to the following criteria. A: There is almost no unpleasantness in the sound. B: There is some noise that is unpleasant, but not to the point of being bothersome. C: The sound is unpleasant.

[0053] Figure 7 shows the average maximum volume during connection and disconnection operations. Table 3 shows the evaluation results for noise discomfort. Note that the noise discomfort level was the same between the two tests, so it is shown as a single evaluation.

[0054] [Table 3]

[0055] Figure 7 shows that samples processed for 30 minutes or more exhibited reduced noise levels during attachment and detachment compared to unprocessed samples. Table 3 also shows that samples processed for 30 minutes or more experienced reduced noise discomfort. Furthermore, samples processed for 60 minutes or more exhibited almost no noise discomfort.

[0056] (Compression set) A test specimen (13 mm in diameter, 6.3 mm thick) molded from addition-crosslinked millable silicone rubber for measuring compression set was placed on a tray inside a UV irradiator (manufactured by Iwasaki Electric Co., Ltd.) and irradiated under the same conditions as described above.

[0057] The compression set was measured for untreated samples, samples treated for 15 minutes, 30 minutes, 45 minutes, and 60 minutes. The compression set was measured at a test temperature of 180°C, a test time of 168 hours, and a compressibility of 25%, according to the method conforming to JIS K 6262. A gear-type aging tester (manufactured by Yasuda Seiki Seisakusho) was used as the constant temperature chamber. The thickness was measured using a constant-pressure thickness gauge (manufactured by Teclock) according to Method A (JIS K 6250). For each sample, n=3 measurements were taken, and the median value was taken as the compression set of that sample. The measurement results for the compression set of each sample are shown in Table 4.

[0058] [Table 4]

[0059] (Coefficient of kinetic friction) A sheet of silicone resin (8cm x 2cm, 0.2cm thick) molded using addition-crosslinked millable silicone rubber was placed on a tray inside a UV irradiator (manufactured by Iwasaki Electric Co., Ltd.) and irradiated under the same conditions as described above.

[0060] The coefficient of dynamic friction was measured for untreated samples, samples treated for 30 minutes, and samples treated for 60 minutes. Specifically, first, the samples were placed on a horizontal test table. Next, a polyethylene film (SPV-C-100; manufactured by Nitto Denko Corporation) with a weight load of 62.98 g was placed on top of the samples as a sliding piece. A force gauge (manufactured by Nidec Corporation) was connected to the sliding piece, and the coefficient of dynamic friction was measured by sliding the piece at a speed of 50 mm / second for 5 seconds. Measurements were taken for each sample with n=5, and the average value was calculated. The measurement results of the coefficient of dynamic friction for each sample are shown in Table 5.

[0061] [Table 5] [Explanation of Symbols]

[0062] 10 sealing member 12 Contact points 20 Lid 22 Lid top part 24 Lid side part 26 Female thread section 28 Groove 30 Bottomed cylinder 32 Bottom of cylinder 34 Cylinder side part 36 Mouth 38 Male screw section 40 airtight containers 50 First pipe 60 Second pipe 61 Main body of pipe 62 Receptacle 64 groove 70 Connecting pipe

Claims

1. A sealing member used by interposing it between a first member and a second member, Formed from silicone resin, For at least a portion of the contact area between the first member and the second member, silicon, oxygen, and carbon were selected from the elements detected by XPS depth profiling, and in a profile where the sum of the atomic concentrations of these elements was set to 100 atomic percent, The thickness of the modified layer at which the ratio of oxygen atom concentrations is 80% or more, when the maximum oxygen atom concentration from the outermost surface to a depth of 200 nm is taken as 100%, is between 500 nm and 1600 nm, and A sealing member in which the difference between the aforementioned maximum value and the oxygen atom concentration at a depth of 1000 nm from the outermost surface is between 5 atomic percent and 12.71 atomic percent.

2. The sealing member according to claim 1, wherein the Shore hardness measured by a Type A durometer of the silicone resin is 30 to 80.

3. The sealing member according to claim 1, which is ring-shaped.

4. The sealing member according to claim 1, which is used by being attached to a groove provided in one of the first member and the second member.

5. The sealing member according to claim 1, wherein the first member is a lid and the second member is a bottomed cylindrical body.

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