Quality management methods for silicone rubber, quality management methods for cables or pipes, and manufacturing methods for laminated structures.

Abstract

This invention provides a quality management method for silicone rubber capable of diagnosing the degree of degradation of silicone rubber due to ultraviolet (UV) exposure using Raman scattering measurement; a method for manufacturing a laminated structure utilizing this silicone rubber quality management method; a quality management method for cables or pipes; and silicone rubber with minimal degradation, laminated structures, and cables or pipes. The silicone rubber quality management method of this invention includes: a measurement step of irradiating the silicone rubber with a laser to measure its Raman spectrum; and a diagnosis step of diagnosing the degree of degradation of the silicone rubber due to UV exposure based on at least one of the intensity of a first peak attributable to Si-O3 stretching vibrations and the intensity of a second peak containing peaks attributable to C-C-O symmetric stretching vibrations in the Raman spectrum.

Description

Technical Field

[0001] This invention relates to silicone rubber and its quality management methods, cables or pipes and their quality management methods, and laminated structures and their manufacturing methods. Background Technology

[0002] Previously, it was known that the Raman spectrum of polyvinyl chloride (PVC) changed due to ultraviolet (UV) exposure (Non-Patent Document 1). According to Non-Patent Document 1, it is believed that C-C bonds and C=C bonds are generated in PVC through UV exposure, and the peaks corresponding to these bonds appear in the Raman spectrum.

[0003] Therefore, by investigating the intensity of the peaks corresponding to C-C bonds and C=C bonds in Raman spectra, the degree of molecular-level structural changes (deterioration) of polyvinyl chloride caused by ultraviolet exposure can be diagnosed.

[0004] Existing technical documents

[0005] Patent documents

[0006] Non-patent document 1: International Publication No. 2016 / 031063 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] Silicone rubber, used as insulation material for cables and pipes in medical devices, is an excellent material due to its high resistance to ultraviolet light and the fact that it does not discolor like polyvinyl chloride even when sterilized by ultraviolet irradiation. However, because it does not discolor even when deteriorated by ultraviolet exposure, the degree of deterioration is difficult to visually confirm. Furthermore, since the mechanism of deterioration of silicone rubber due to ultraviolet exposure is unknown, it is difficult to diagnose its service life using other methods. Therefore, if the degree of deterioration could be diagnosed based on Raman scattering measurement using the method described in Non-Patent Literature 1, it would be extremely useful in the quality management of silicone rubber.

[0009] However, whether the Raman spectrum changes due to ultraviolet exposure, or how which peak changes under such conditions, varies depending on the substance being measured. Therefore, the information on the Raman spectrum of polyvinyl chloride described in Non-Patent Document 1 cannot be used to evaluate the Raman spectra of substances other than polyvinyl chloride.

[0010] The present invention aims to provide a quality management method for silicone rubber that can use Raman scattering measurement to diagnose the degree of deterioration of silicone rubber caused by ultraviolet exposure, a manufacturing method for a laminated structure using the quality management method for silicone rubber, a quality management method for cables or pipes, and silicone rubber with a low degree of deterioration, laminated structures, and cables or pipes.

[0011] Methods for solving problems

[0012] To address the aforementioned issues, this invention provides a quality management method for silicone rubber, comprising: a measurement step of irradiating the silicone rubber with a laser and measuring its Raman spectrum; and a diagnostic step of diagnosing the degree of deterioration of the silicone rubber due to ultraviolet exposure based on at least one of the intensity of a first peak attributable to the Si-O3 stretching vibration and the intensity of a second peak containing a peak attributable to the CCO symmetric stretching vibration in the Raman spectrum.

[0013] Invention Effects

[0014] According to the present invention, a method for quality management of silicone rubber that can use Raman scattering measurement to diagnose the degree of deterioration of silicone rubber caused by ultraviolet exposure, a method for manufacturing a laminated structure using the quality management method of silicone rubber, a method for quality management of cables or pipes, and silicone rubber with low degree of deterioration, laminated structures, and cables or pipes can be provided. Attached Figure Description

[0015] Figure 1 It is the structural formula of silicone rubber.

[0016] Figure 2 (a) to (c) are the structural formulas of the material containing particles dispersed within the microparticle-dispersed silicone rubber.

[0017] Figure 3 This is a vertical cross-sectional view of the stacked structure involved in this embodiment.

[0018] Figure 4 This is a top view schematically illustrating the configuration of the probe cable involved in this embodiment.

[0019] Figure 5 It is along Figure 4 The diagram shows a cross-sectional view of the probe cable cut off by the AA line.

[0020] Figure 6 (a) to (c) are radial cross-sectional views of the medical tube involved in this embodiment.

[0021] Figure 7 (a) refers to ultraviolet radiation in the UV-C wavelength region with an illuminance of 1.2–1.3 mW / cm². 2 Raman spectra of silicone rubber after irradiation from 0 to 800 hours. Figure 7 (b) is an optical microscope image of the surface of silicone rubber after it has been irradiated with ultraviolet light for 800 hours.

[0022] Figure 8(a) is a graph showing the ratio (integral intensity ratio) of the integrated intensity of peaks A1, A2, and A4 to the integrated intensity of peak A3 in silicone rubber. Figure 8 (b) is a graph showing the ratio (peak height ratio) of the peak heights of peaks A1, A2, and A4 to the peak height of peak A3.

[0023] Figure 9 (a) refers to ultraviolet radiation in the UV-C wavelength region with an illuminance of 1.2–1.3 mW / cm². 2 Raman spectra of silicone rubber after irradiation from 0 to 800 hours. Figure 9 (b) is an optical microscope image of the surface of the microparticle-dispersed silicone rubber after 800 hours of ultraviolet irradiation.

[0024] Figure 10 (a) is a graph showing the ratio (integral intensity ratio) of the integrated intensity of peaks B1, B2, and B4 to the integrated intensity of peak B3 in particulate dispersed silicone rubber. Figure 10 (b) is a graph showing the ratio (peak height ratio) of the peak heights of peaks B1, B2, and B4 to the peak height of peak B3.

[0025] Symbol Explanation

[0026] 1: Layered structure, 10: First layer, 11: Second layer, 20: Probe cable, 23: Sheath, 24: Coating, 40a, 40b, 40c: Medical tubing, 41: Tube body, 42: Outer coating, 43: Inner coating. Detailed Implementation

[0027] [Implementation Method]

[0028] (Properties of silicone rubber)

[0029] Figure 1 This is the structural formula for silicone rubber. Silicone rubber is a type of silicone resin, used as an insulating material for things like probe cables that can be connected to medical devices, and tubes for inserting catheters.

[0030] As mentioned above, silicone rubber is superior to polyvinyl chloride (PVC), which is commonly used in cables and pipes for medical applications, in terms of its high resistance to ultraviolet light and its near-discoloration even when sterilized by ultraviolet irradiation. However, on the other hand, because silicone rubber does not change color like PVC even when it undergoes embrittlement or other deterioration due to ultraviolet exposure, it is difficult to visually diagnose the degree of deterioration caused by ultraviolet exposure.

[0031] Furthermore, silicone rubber, by dispersing silicon-containing particles such as silicone resin particles and silica (silica) particles within it, can suppress surface stickiness and improve sliding properties. Therefore, by layering silicone rubber containing silicon particles dispersed on a surface of silicone rubber without particles and covering its surface, surface stickiness of silicone rubber parts can be suppressed and sliding properties improved. Hereinafter, this silicone rubber with dispersed silicon particles will be referred to as particle-dispersed silicone rubber.

[0032] That is, the particulate dispersed silicone rubber has a silicone rubber as a base material and Si-containing particles dispersed in the silicone rubber. The particles are silicone resin particles, silica particles, or a mixture of both. The particles preferably have a higher hardness than the base material (for example, a hardness of about 1.1 times or more on a Shore A hardness scale).

[0033] Here, the average particle size of the particles contained in the particulate dispersed silicone rubber is, for example, 1 μm or more and 10 μm or less. It should be noted that "average particle size" in this specification refers to the particle size measured by laser diffraction scattering. Furthermore, the mass percentage of the particles contained in the particulate dispersed silicone rubber is, for example, 10% or more and 60% or less. Because the particulate dispersed silicone rubber contains multiple particles, it forms an uneven surface. Therefore, compared to silicone rubber without an uneven surface, the particulate dispersed silicone rubber has a smaller contact area with the contacting object and higher slip properties.

[0034] Figure 2 (a) to (c) are the structural formulas of the material containing particles dispersed within the microparticle-dispersed silicone rubber. Figure 2 (a) represents the structural formula of organosilicon resin. Figure 2 (b) represents the structural formula of silicon dioxide. Additionally, for reference, in Figure 2 (c) shows the structural formula of silicone rubber.

[0035] The main difference between silicone rubber and silicone resin lies in the number of reactive groups (e.g., methyl groups) in their structural formulas. Figure 2 As shown in (a) to (c), the number of reactive groups in the structural formula of silicone rubber is greater than that in the structural formula of silicone resin, and silica contains no reactive groups. Since the more reactive groups a material contains, the softer it is, and the fewer reactive groups it contains, the harder it is. Therefore, among silicone rubber, silicone resin, and silica, silica has the highest hardness, followed by silicone resin, and silicone rubber has the lowest hardness. Furthermore, regarding mass, silica has the largest mass, followed by silicone resin, and silicone rubber has the smallest mass.

[0036] From the viewpoint of suppressing surface deformation due to unevenness when particulate dispersed silicone rubber comes into contact with a contacting object, silica with high hardness is preferred, followed by silicone resin. This is because, when pressure is applied to the surface of the particulate dispersed silicone rubber by the contacting object, the higher the hardness of the particles, the better the deformation due to unevenness can be suppressed. Therefore, the increase in the contact area with the contacting object can be suppressed, maintaining slip properties.

[0037] On the other hand, as mentioned above, silica has a large mass, so silica particles tend to settle in the liquid silicone rubber used as the base material during the manufacturing process of particulate dispersed silicone rubber. Compared with silicone rubber particles and silicone resin particles, they are difficult to disperse in silicone rubber. Therefore, from the viewpoint of improving the uniformity of dispersion in particulate dispersed silicone rubber, it is preferable to use particles composed of silicone rubber or silicone resin.

[0038] Therefore, in order to balance the maintenance of the sliding properties of the particulate dispersed silicone rubber when it comes into contact with the contacting material and the uniformity of the dispersion of the particulates in the silicone rubber as the base material, it is best to use silicone resin particles as the particles dispersed in the particulate dispersed silicone rubber.

[0039] (Quality Management Methods for Organosilicon Rubber)

[0040] According to the quality management method for silicone rubber of this embodiment, Raman scattering measurement can be used to diagnose the degree of deterioration caused by ultraviolet exposure, thereby managing the quality of silicone rubber and particulate dispersed silicone rubber. Furthermore, based on Raman scattering measurement, the degree of deterioration caused by ultraviolet exposure can be diagnosed while maintaining the original state of silicone rubber and particulate dispersed silicone rubber.

[0041] Here, the ultraviolet exposure of silicone rubber and particulate dispersed silicone rubber includes: exposure caused by intentional exposure to ultraviolet light for purposes such as sterilization; exposure caused by use in special environments that emit ultraviolet light; and exposure caused by manufacturing or storage in environments exposed to direct sunlight.

[0042] Furthermore, the degradation of silicone rubber and particulate dispersed silicone rubber caused by ultraviolet exposure, such as embrittlement, can also be diagnosed by Raman scattering measurement according to the quality management method of silicone rubber involved in this embodiment, thereby managing the quality of silicone rubber and particulate dispersed silicone rubber.

[0043] The quality management method for silicone rubber according to this embodiment, for example when applied to silicone rubber that does not contain Si particles, includes: a measurement step of irradiating the silicone rubber with a laser to measure its Raman spectrum; and a diagnostic step of diagnosing the degree of deterioration of the silicone rubber due to ultraviolet exposure based on at least one of the intensity of a first peak attributable to the Si-O3 stretching vibration and the intensity of a second peak containing the CCO symmetric stretching vibration attributable to a free alcohol (tertiary alcohol) in the measured Raman spectrum. Here, the peak intensity in the Raman spectrum in this embodiment refers to the integrated intensity or peak height.

[0044] The first peak is at 600 cm⁻¹ in the Raman spectrum. -1 The above 660cm -1 The peak with the highest intensity is selected within the following range. Additionally, the second peak is at 730 cm⁻¹ in the Raman spectrum. -1 Above 770cm -1 The peak with the highest intensity is selected from the following range. It should be noted that the positions of the first and second peaks may shift within the above wavenumber range depending on factors such as the temperature of the silicone rubber during the measurement.

[0045] The second peak may not be a separate peak belonging to the CCO symmetric stretching vibration, but rather a composite peak of the peak belonging to the CCO symmetric stretching vibration and the peak belonging to the Si-C stretching vibration.

[0046] The inventors of this application discovered that exposing silicone rubber to ultraviolet light increases the intensity of the first and second peaks mentioned above. This is believed to be due to the formation of new molecular structures containing Si-O3 bonds and CCO bonds in the silicone rubber through ultraviolet exposure. Therefore, based on at least one of the intensities of the first and second peaks, the degree of degradation of the silicone rubber caused by ultraviolet exposure can be diagnosed.

[0047] In the aforementioned diagnostic process, the intensity of the first and second peaks can be used as a benchmark, specifically the third peak, which belongs to the SiC2 stretching vibration and whose intensity remains almost unchanged before and after UV exposure of the silicone rubber. That is, the degree of degradation of the silicone rubber due to UV exposure can be diagnosed based on at least one of the ratio of the intensity of the first peak to the intensity of the third peak belonging to the SiC2 stretching vibration in the Raman spectrum and the ratio of the intensity of the second peak to the intensity of the third peak. The third peak is at 660 cm⁻¹. -1 Above 730cm -1 The maximum strength is taken from the following range.

[0048] Specifically, for example, the degree of deterioration of silicone rubber due to ultraviolet exposure can be diagnosed based on whether the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak in the Raman spectrum measured at a temperature of 20°C is less than 0.23. In this case, it can also be used as a criterion for judging whether the quality of silicone rubber is acceptable; if the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is less than 0.23, it is considered acceptable; if it is greater than 0.23, it is considered unacceptable.

[0049] Furthermore, based on whether the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak in the Raman spectrum measured at a temperature of 20°C is less than 0.02, the degree of deterioration of the silicone rubber caused by ultraviolet exposure can be diagnosed. In this case, it can also be used as a criterion for judging whether the quality of the silicone rubber is acceptable; if the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is less than 0.02, it is considered acceptable; if it is greater than 0.02, it is considered unacceptable.

[0050] Furthermore, based on whether the ratio of the peak height of the first peak to the peak height of the third peak in the Raman spectrum measured at a temperature of 20°C is less than 0.18, the degree of deterioration of the silicone rubber caused by ultraviolet exposure can be diagnosed. In this case, it can also be used as a criterion for judging whether the quality of the silicone rubber is acceptable; if the ratio of the peak height of the first peak to the peak height of the third peak is less than 0.18, it is considered acceptable; if it is greater than 0.18, it is considered unacceptable.

[0051] Furthermore, based on whether the ratio of the peak height of the second peak to the peak height of the third peak in the Raman spectrum measured at a temperature of 20°C is less than 0.023, the degree of deterioration of the silicone rubber caused by ultraviolet exposure can be diagnosed. In this case, it can also be used as a criterion for judging whether the quality of the silicone rubber is acceptable; if the ratio of the peak height of the second peak to the peak height of the third peak is less than 0.023, it is considered acceptable; if it is greater than 0.023, it is considered unacceptable.

[0052] Here, the integral intensities and peak heights of the first to third peaks are calculated using peak profiles obtained analytically through fitting statistical distribution functions such as the Pseudo-voigt function, Lorentz function, and Gauss distribution function, after background correction. Background correction is performed to remove the influence of unavoidable background light sources, such as fluorescence, Rayleigh and Mie scattering from laser illumination, and other interfering light, which are not considered to be caused by the molecular structure of silicone rubber. This is done by subtracting the background profile (baseline) obtained analytically through fitting using polynomial functions, spline functions, etc., from the aforementioned peak profiles. Furthermore, the integration range for calculating the integral intensities of the first to third peaks is the range between the two intersection points of the aforementioned peak profile and the background profile.

[0053] Furthermore, the lower limit for the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 0.201, and the lower limit for the ratio of the peak height of the first peak to the peak height of the third peak is 0.127. It should be noted that these lower limits are for silicone rubber in a state where it is not exposed to ultraviolet light. Additionally, in the state where silicone rubber is not exposed to ultraviolet light, the integrated intensity and peak height of the second peak are approximately zero; therefore, the lower limits for the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak and the ratio of the peak height of the second peak to the peak height of the third peak are both zero.

[0054] Furthermore, when the quality management method for silicone rubber of this embodiment is applied to particulate dispersed silicone rubber, it includes: a measurement step of irradiating the particulate dispersed silicone rubber with a laser to measure the Raman spectrum; and a diagnostic step of diagnosing the degree of deterioration of the particulate dispersed silicone rubber due to ultraviolet exposure based on at least one of the intensity of a first peak containing a peak attributable to the Si-CH3 yaw vibration and the intensity of a second peak containing a peak attributable to the CCO symmetric stretching vibration of the free alcohol (tertiary alcohol) in the measured Raman spectrum.

[0055] The first peak is at 770 cm⁻¹ in the Raman spectrum. -1 Above 850cm -1 The peak with the highest intensity is selected within the following range. Additionally, the second peak is at 730 cm⁻¹ in the Raman spectrum. -1 Above 770cm -1 The peak with the highest intensity is selected from the following range. It should be noted that the positions of the first and second peaks may shift within the above wavenumber range depending on factors such as the temperature at which the microparticles are dispersed in the silicone rubber during the measurement.

[0056] The first peak may not be a separate peak belonging to the Si-CH3 yaw vibration, but rather a composite peak belonging to both the Si-CH3 yaw vibration and C-Si-C stretching vibrations. Similarly, the second peak may not be a separate peak belonging to the CCO symmetric stretching vibration, but rather a composite peak belonging to both the CCO symmetric stretching vibration and Si-C stretching vibrations.

[0057] The inventors of this application discovered that by exposing the aforementioned particulate-dispersed silicone rubber to ultraviolet light, the intensities of the first and second peaks increase. This is believed to be due to the formation of new molecular structures containing Si-CH3 bonds and CCO bonds in the particulate-dispersed silicone rubber through ultraviolet exposure. Therefore, based on at least one of the intensities of the first and second peaks, the degree of degradation of the particulate-dispersed silicone rubber caused by ultraviolet exposure can be diagnosed.

[0058] In particulate dispersed silicone rubber, since Si-containing particles (silicone resin particles, silica particles, or a mixture of both) are dispersed within the silicone rubber, Si-based oxides and organic substances coexist. Furthermore, it is believed that exposure to ultraviolet light causes localized reactions among these particles, thereby increasing the intensity of the first and second peaks.

[0059] In the aforementioned diagnostic process, the intensity of the first and second peaks can be used as a benchmark, specifically the third peak, which belongs to the SiC2 stretching vibration and whose intensity remains almost unchanged before and after UV exposure of the particulate-dispersed silicone rubber. That is, the degree of deterioration of the particulate-dispersed silicone rubber due to UV exposure can be diagnosed based on at least one of the ratio of the intensity of the first peak to the intensity of the third peak belonging to the SiC2 stretching vibration in the Raman spectrum and the ratio of the intensity of the second peak to the intensity of the third peak. The third peak is at 660 cm⁻¹. -1 Above 730cm -1 The maximum strength is taken from the following range.

[0060] Specifically, for example, the degree of deterioration of particulate-dispersed silicone rubber due to ultraviolet exposure can be diagnosed based on whether the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak in the Raman spectrum measured at a measurement temperature of 20°C is less than 2.1. In this case, it can also be used as a criterion for judging whether the quality of particulate-dispersed silicone rubber is qualified; if the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is less than 2.1, it is judged as qualified, and if it is greater than 2.1, it is judged as unqualified.

[0061] Furthermore, based on whether the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak in the Raman spectrum measured at a temperature of 20°C is less than 1.3, the degree of deterioration of the particulate-dispersed silicone rubber caused by ultraviolet exposure can be diagnosed. In this case, it can also be used as a criterion for judging whether the quality of the particulate-dispersed silicone rubber is acceptable; if the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is less than 1.3, it is considered acceptable; if it is greater than 1.3, it is considered unacceptable.

[0062] Furthermore, based on whether the ratio of the peak height of the first peak to the peak height of the third peak in the Raman spectrum measured at a temperature of 20°C is less than 0.94, the degree of deterioration of the particulate-dispersed silicone rubber caused by ultraviolet exposure can be diagnosed. In this case, it can also be used as a criterion for judging whether the quality of the particulate-dispersed silicone rubber is acceptable; if the ratio of the peak height of the first peak to the peak height of the third peak is less than 0.94, it is considered acceptable; if it is greater than 0.94, it is considered unacceptable.

[0063] Furthermore, based on whether the ratio of the peak height of the second peak to the peak height of the third peak in the Raman spectrum measured at a temperature of 20°C is less than 0.71, the degree of deterioration of the particulate-dispersed silicone rubber caused by ultraviolet exposure can be diagnosed. In this case, it can also be used as a criterion for judging whether the quality of the particulate-dispersed silicone rubber is acceptable; if the ratio of the peak height of the second peak to the peak height of the third peak is less than 0.71, it is considered acceptable; if it is greater than 0.71, it is considered unacceptable.

[0064] Here, the peak heights and integral intensities of the first to third peaks are calculated using peak profiles obtained analytically through fitting statistical distribution functions such as the Pseudo-voigt function, Lorentz function, and Gauss distribution function, after background correction. Background correction is performed to remove the influence of unavoidable background light, such as light generated by fluorescence, Rayleigh and Mie scattering from laser irradiation, and other interfering light, which is not considered to be caused by the molecular structure of the microparticle-dispersed silicone rubber. This is done by subtracting the background profile (baseline) obtained analytically through fitting using polynomial functions, spline functions, etc., from the aforementioned peak profiles. Furthermore, the integration range for calculating the integral intensities of the first to third peaks is the range between the two intersection points of the aforementioned peak profiles and the background profile.

[0065] It should be noted that the lower limit for the ratio of the integrated intensity of the first peak to the integrated intensity of the third peak is 1.0, and the lower limit for the ratio of the peak height of the first peak to the peak height of the third peak is 0.46. These lower limits are for the particulate-dispersed silicone rubber under conditions where it has not been exposed to ultraviolet light. Additionally, the lower limit for the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 0.23, and the lower limit for the ratio of the peak height of the second peak to the peak height of the third peak is 0.185. Again, these lower limits are for the particulate-dispersed silicone rubber under conditions where it has not been exposed to ultraviolet light.

[0066] (Silicone rubber)

[0067] According to this embodiment, as a silicone rubber that deteriorates less due to ultraviolet exposure, it is possible to provide silicone rubber or particulate dispersed silicone rubber whose quality can be managed by the above-described silicone rubber quality management method.

[0068] The silicone rubber of this embodiment satisfies at least one of the following first and second conditions: First condition: the ratio of the intensity of the first peak attributable to the Si-O3 stretching vibration to the intensity of the third peak attributable to the SiC2 stretching vibration in the Raman spectrum obtained by laser irradiation is 0.23 or less; Second condition: the ratio of the intensity of the second peak, which includes a peak attributable to the CCO symmetric stretching vibration, to the intensity of the third peak is 0.02 or less. Hereinafter, this silicone rubber will be referred to as silicone rubber A.

[0069] Other silicone rubbers involved in this embodiment are, for example, particulate dispersed silicone rubbers, satisfying at least one of the following first and second conditions: First condition: the ratio of the intensity of the first peak belonging to the Si-CH3 yaw vibration to the intensity of the third peak belonging to the SiC2 stretching vibration in the Raman spectrum obtained by laser irradiation is 2.1 or less; Second condition: the ratio of the intensity of the second peak belonging to the CCO symmetric stretching vibration to the intensity of the third peak is 1.3 or less. Hereinafter, this silicone rubber will be referred to as silicone rubber B.

[0070] (Laminated structures and their manufacturing methods)

[0071] As described above, particulate-dispersed silicone rubber exhibits superior surface lubricity compared to particulate-free silicone rubber. On the other hand, particulate-free silicone rubber, being composed of a single raw material, excels in density and smoothness compared to particulate-dispersed silicone rubber. Therefore, for applications such as cables and pipes, a composition in which particulate-dispersed silicone rubber is laminated onto silicone rubber is preferred.

[0072] Figure 3This is a vertical cross-sectional view of the laminated structure 1 according to this embodiment. The laminated structure 1 is a structure obtained by laminating a second layer 11 made of particulate dispersed silicone rubber on a first layer 10 made of silicone rubber. The second layer 11 suppresses surface stickiness and improves sliding properties. In addition, at least either the first layer 10 or the second layer 11 in the laminated structure 1 is made of silicone rubber or particulate dispersed silicone rubber whose quality is managed by the above-described silicone rubber quality management method.

[0073] It should be noted that, as the base material for the particulate dispersed silicone rubber used in the second layer 11, either an addition-reaction type silicone rubber coating agent or a condensation-reaction type silicone rubber coating agent can be used. In particular, from the viewpoint of adhesion and abrasion resistance to the first layer 10 composed of silicone rubber, an addition-reaction type silicone rubber coating agent is preferred.

[0074] That is, the laminated structure 1 has, for example, a first layer 10 made of silicone rubber and a second layer 11 made of particulate dispersed silicone rubber laminated on the first layer 10, satisfying at least one of the following first and second conditions: first condition: the silicone rubber of the first layer 10 is the aforementioned silicone rubber A; second condition: the particulate dispersed silicone rubber of the second layer 11 is the aforementioned silicone rubber B.

[0075] To ensure the smoothness of the surface of the laminated structure 1 through the second layer 11, the thickness of the second layer 11 is preferably 15 μm or more. Alternatively, the second layer 11 may be laminated on both sides of the first layer 10.

[0076] The laminated structure 1 can take various forms depending on its application. For example, it can be formed into a tubular shape when used as insulation for cables or pipes, and into a sheet shape when used as sheet material for high UV resistance in constant temperature rooms.

[0077] Furthermore, the manufacturing method of the laminated structure 1 according to this embodiment includes, for example, a step of forming a first layer 10 made of silicone rubber; and a step of laminating a second layer 11 made of particulate dispersed silicone rubber onto the first layer 10, satisfying at least one of the following first and second conditions: the first condition is that the silicone rubber of the first layer 10 is silicone rubber whose degree of deterioration due to ultraviolet exposure has been diagnosed by the quality management method of silicone rubber according to this embodiment described above; the second condition is that the particulate dispersed silicone rubber of the second layer 11 is silicone rubber whose degree of deterioration due to ultraviolet exposure has been diagnosed by the quality management method of silicone rubber according to this embodiment described above.

[0078] (Cables and conduits)

[0079] The laminated structure 1 of this embodiment can be used as an insulator for cables, especially for cables used in medical applications.

[0080] In recent years, silicone rubber, with its excellent heat resistance and chemical resistance, has been researched as a sheathing material for cables used in medical applications. However, as mentioned above, silicone rubber has the problem of poor slippage. Therefore, when silicone rubber is used as a cable sheathing material, problems arise such as the cable easily snagging on other components and dust easily adhering to the cable surface.

[0081] In particular, if the cable easily snags on other components, operation becomes difficult, such as with probe cables connected to medical devices like ultrasound imaging units. This is because in ultrasound imaging units, the ultrasound probe, connected to the probe cable, is moved across the body during the examination; therefore, if the probe cable easily snags on other cables, clothing, etc., the ultrasound probe cannot be moved smoothly. Therefore, for cables used in medical applications, it is desirable for them to be non-sticky and have a surface with good sliding properties.

[0082] The laminated structure 1 of this embodiment has a second layer 11 with excellent sliding properties, therefore, a cable with excellent surface sliding properties can be manufactured using the laminated structure 1. Hereinafter, as an example of a cable having an insulator composed of the laminated structure 1, a probe cable that can be connected to a medical device will be described.

[0083] Figure 4 This is a top view schematically illustrating the structure of the probe cable 20 according to this embodiment. (See attached image.) Figure 4 As shown, at one end of the probe cable 20, an ultrasonic probe terminal 32, which is connected to the ultrasonic probe, is installed via a protective cover 31 that protects that end. Additionally, at the other end of the probe cable 20, a connector 33, which is connected to the main body of the ultrasonic camera device, is installed.

[0084] Figure 5 It is along Figure 4 The diagram shows a cross-sectional view of the probe cable 20 cut along the AA line. Inside the probe cable 20 are several wires 21, such as multiple coaxial cables, covered by a braided shielding member or similar shielding member. A sheath 23 covers the shielding member 22.

[0085] Furthermore, in the probe cable 20 of this embodiment, a film 24 is formed that covers the periphery of the sheath 23 and is tightly fitted to the sheath 23. A protective cover 31 is installed around the film 24 via an adhesive 25. The adhesive 25 is, for example, a silicone-based adhesive or an epoxy-based adhesive.

[0086] The sheath 23 and the coating 24 of the probe cable 20 are each composed of a first layer 10 and a second layer 11 of the laminated structure 1. That is, in the probe cable 20, the laminated structure 1 is used as both the sheath 23 and the coating 24. By using the coating 24, which is composed of the second layer 11 with excellent sliding properties, snagging of the probe cable 20 caused by the stickiness of the surface of the sheath 23 can be suppressed. The thickness of the coating 24 is, for example, 3 μm or more and 100 μm or less.

[0087] Next, an example of the manufacturing method of the probe cable 20 in this embodiment will be described. First, multiple (for example, more than 100) wires 21 are bundled together. Then, a shield 22 is formed to cover the bundled multiple wires 21.

[0088] Next, the first layer 10 and the second layer 11 of the laminated structure 1 are sequentially formed to cover the shield 22, forming the sheath 23 and the film 24. The sheath 23 can be formed, for example, by extrusion molding using an extruder. The film 24 can be formed, for example, by impregnation, spraying, or roller coating. In the impregnation method, the probe cable 20 formed to the sheath 23 is passed through liquid film material and pulled up, thereby forming the film 24 on the surface of the sheath 23. This impregnation method is superior to the spraying and roller coating methods in terms of the uniformity of the film thickness of the formed film 24.

[0089] Since the liquid coating material used in the impregnation method contains microparticles, the coating 24 is composed of silicone rubber as the base material and microparticles dispersed in the silicone rubber. At this time, by adjusting the content of microparticles contained in the liquid coating material, the content of microparticles contained in the coating 24 can be controlled.

[0090] In addition, the laminated structure 1 of this embodiment can be used as an insulator for use in tubes (hollow tubes), especially for tubes used in medical applications such as catheters.

[0091] Figure 6 (a) to (c) are radial cross-sectional views of the medical tube involved in this embodiment. Figure 6 (a) The medical tube 40a shown has an outer coating 42 on the outer surface 41a of the tube body 41. Figure 6 (b) The medical tube 40b shown has an inner membrane 43 on the inner surface 41b of the tube body 41. Figure 6 (c) The medical tube 40c shown has an outer membrane 42 and an inner membrane 43 on the outer surface 41a and inner surface 41b of the tube body 41, respectively.

[0092] The main body 41 of the medical tubes 40a, 40b, and 40c is composed of the first layer 10 of the laminated structure 1, and the outer membrane 42 and the inner membrane 43 are composed of the second layer 11 of the laminated structure 1.

[0093] As illustrated in medical tubes 40a, 40b, and 40c, the tubes involved in this embodiment include a tube body 41, an outer membrane 42 covering the outer surface 41a of the tube body 41, an inner membrane 43 covering the inner surface 41b of the tube body 41, or both an outer membrane 42 and an inner membrane 43. The tube body 41 is composed of a first layer 10 of a laminated structure 1, and the outer membrane 42 and the inner membrane 43 are composed of a second layer 11 of the laminated structure 1.

[0094] The tube described in this embodiment has excellent sliding properties on both its inner and outer surfaces, thus allowing for smooth insertion and removal of instruments, such as medical tubes like catheters, when they are inserted into the tube. Furthermore, the tube described in this embodiment can be used in tubing kits for endoscopic surgical instruments, tubing kits for ultrasonic surgical instruments, tubing for blood analyzers, tubing for oxygen concentrators, artificial dialysis blood circuits, artificial heart-lung circuits, endotracheal tubes, and the like.

[0095] (Quality management methods for cables or pipes)

[0096] According to this embodiment, the above-described quality management method for silicone rubber can be used to diagnose the degree of deterioration of the insulator caused by ultraviolet exposure, and to implement quality management of cables or tubes having insulators composed of silicone rubber or particulate dispersed silicone rubber, or probe cables 20, medical tubes 40a, 40b, 40c, etc., having insulators composed of laminated structures 1 made of silicone rubber and particulate dispersed silicone rubber.

[0097] That is, in managing the quality of cables or pipes with insulators made of silicone rubber, as described above, the degree of deterioration of silicone rubber due to ultraviolet exposure can be diagnosed by Raman scattering measurement, thereby managing the quality of cables or pipes.

[0098] Furthermore, in managing the quality of cables or pipes with insulators made of particulate dispersed silicone rubber, as described above, the degree of deterioration of the particulate dispersed silicone rubber due to ultraviolet exposure can be diagnosed by Raman scattering measurement, thereby managing the quality of the cables or pipes.

[0099] Thus, according to the cable or pipe quality management method of this embodiment, the degree of deterioration of silicone rubber and particulate silicone rubber caused by ultraviolet exposure can be diagnosed, and quality can be managed. Therefore, for example, by quantitatively controlling the time-related deterioration of cables or pipes subjected to repeated ultraviolet irradiation sterilization, expected lifespan and reliability can be accurately managed.

[0100] It should be noted that when diagnosing silicone rubber or particulate silicone rubber exposed on the surface of a cable or tube (e.g., the sheath 24 of probe cable 20, the outer sheath 42 of medical tubes 40a, 40c), the cable or tube can be placed in its original state in the Raman scattering measurement device for non-destructive measurement. When diagnosing silicone rubber or particulate silicone rubber not exposed on the surface of a cable or tube (e.g., the sheath 23 of probe cable 20, the tube body 41 of medical tubes 40a, 40b, 40c, the inner sheath 43), the cable or tube can be cut open for measurement.

[0101] Furthermore, by using a gun-shaped Raman scattering measuring device that allows free movement of the laser irradiation section and the scattered light receiving section, even unprocessed long cables or tubes that are difficult to measure in conventional measuring devices can be measured in their original state. In this case, for example, for cables or tubes wound on a spool, the measurement can be performed while the spool is rotated.

[0102] (Effects of the implementation method)

[0103] According to the above embodiments, by using Raman scattering measurement, it is possible to diagnose the deterioration of silicone rubber and particulate dispersed silicone rubber caused by ultraviolet exposure, which is difficult to diagnose visually, and to manage their quality. Furthermore, it is possible to diagnose the deterioration of insulators made of silicone rubber and particulate dispersed silicone rubber in cables and pipes caused by ultraviolet exposure, and to manage their quality.

[0104] Furthermore, by implementing quality management of the silicone rubber and the particulate dispersed silicone rubber, it is possible to provide silicone rubber, particulate dispersed silicone rubber, and laminated structures composed of silicone rubber and particulate dispersed silicone rubber with minimal deterioration due to ultraviolet exposure. Consequently, it is possible to provide cables and pipes with silicone rubber and particulate dispersed silicone rubber as insulators that do not deteriorate due to ultraviolet exposure.

[0105] Furthermore, the quality management methods for silicone rubber, cables or pipes, and manufacturing methods for laminated structures described above can also be applied to materials development using materials informatics (MI) that flexibly utilizes machine learning, artificial intelligence (AI), and other methods to analyze data.

[0106] Example 1

[0107] First, the silicone rubber described in this embodiment, processed into sheet form, was prepared, and Raman scattering measurements were performed. The Raman scattering measurements were conducted using a RAMAN force Standard VIS-NIR-HS manufactured by Nanophoton Co., Ltd., under the following conditions: laser wavelength of 532 nm, entrance slit width of the spectrometer of 50 μm, and diffraction grating line count of 300 gr / mm (center wavenumber of the measurement wavenumber range was 2450 cm⁻¹). -1 The ratio of the reduced light intensity after the ND filter to the maximum laser light intensity (reduction ratio) is 220 / 255, and the measurement temperature is 20℃.

[0108] Figure 7 (a) refers to ultraviolet radiation in the UV-C wavelength region with an illuminance of 1.2–1.3 mW / cm². 2 Raman spectra of silicone rubber after irradiation from 0 to 800 hours. In the Raman spectra, at 600 cm⁻¹... -1 The above 660cm -1 The peak with the highest intensity within the following range is taken as peak A1, at 730 cm⁻¹. -1 Above 770cm -1 The peak with the highest intensity within the following range is taken as peak A2, at 660 cm⁻¹. -1 Above 730cm -1 The peak with the highest intensity within the following range is taken as peak A3, at 770 cm⁻¹. -1 Above 850cm -1 The peak with the highest intensity within the following range is designated as peak A4. These Raman spectra are approximately 640 cm⁻¹. -1 Peak A1 is caused by the stretching vibration of Si-O3, and is approximately 750 cm⁻¹. -1 Peak A2 is caused by the symmetric stretching vibration of CCO, and is approximately 710 cm⁻¹. -1 Peak A3 is caused by the stretching vibration of SiC2, and is approximately 795 cm⁻¹. -1 Peak A4 is caused by the yaw vibration of Si-CH3.

[0109] Figure 7 (b) is an optical microscope image of the surface of silicone rubber after it has been irradiated with ultraviolet light for 800 hours. Figure 7 (b) The black dot indicates the observation position (laser irradiation position) for Raman scattering measurement, which is the same as the observation position after 0 hours (no irradiation), 400 hours and 658 hours of ultraviolet irradiation.

[0110] Figure 8 (a) is a graph showing the ratio of the integrated intensity of peaks A1, A2, and A4 to the integrated intensity of peak A3 in silicone rubber (integrated intensity ratio). Figure 8(b) is a graph showing the ratio (peak height ratio) of the peak heights of peaks A1, A2, and A4 to the peak height of peak A3. It is shown in Table 1 below. Figure 8 The values ​​of each plotted point in (a) are shown in Table 2. Figure 8 (b) The values ​​of each plotted point.

[0111] [Table 1]

[0112]

[0113] [Table 2]

[0114]

[0115] according to Figure 8 (a) Figure 8 (b) The integrated intensity ratio and peak height ratio of peak A1 begin to increase when the UV irradiation time exceeds 658 hours. This confirms that as silicone rubber deteriorates due to UV exposure, the integrated intensity ratio and peak height ratio of peak A1 increase.

[0116] The 658-hour ultraviolet irradiation time, one of the ultraviolet irradiation times in this embodiment, is the time at which silicone rubber begins to deteriorate due to ultraviolet exposure, derived from a visual test observing crack formation. The integrated intensity ratio and peak height ratio (represented by the dashed line R1) of peak A1 at 658 hours of ultraviolet irradiation are approximately 0.23 and 0.18, respectively, and therefore can be used as benchmark values ​​for diagnosing the degree of deterioration of silicone rubber caused by ultraviolet exposure.

[0117] It should be noted that cracks in silicone rubber do not necessarily occur when deterioration begins due to UV exposure. Therefore, in the aforementioned visual tests, multiple experiments were repeated, and the shortest crack initiation time was taken as the time when deterioration begins due to UV exposure. Furthermore, the fact that cracks in silicone rubber do not necessarily occur when deterioration begins due to UV exposure means that diagnosing the degree of deterioration caused by UV exposure in silicone rubber based on crack initiation is difficult.

[0118] In addition, according to Figure 8 (a) Figure 8 (b) The integrated intensity ratio and peak height ratio of peak A2 increase with increasing UV irradiation time. This confirms that as silicone rubber deteriorates due to UV exposure, the integrated intensity ratio and peak height ratio of peak A2 increase.

[0119] The integrated intensity ratio and peak height ratio (represented by the dashed line R2) of peak A2 after 658 hours of ultraviolet irradiation are approximately 0.02 and 0.023, respectively, and therefore can be used as benchmark values ​​for diagnosing the degree of degradation of silicone rubber caused by ultraviolet exposure.

[0120] On the other hand, according to Figure 8 (a) Figure 8 (b) It could not be confirmed that the integral intensity ratio and peak height ratio of peak A4 increased significantly with the increase of ultraviolet irradiation time.

[0121] Example 2

[0122] First, a sheet-like laminated structure 1 according to this embodiment, consisting of a first layer 10 made of silicone rubber and a second layer 11 made of particulate dispersed silicone rubber, was prepared. Raman scattering measurements were then performed on the surface made of particulate dispersed silicone rubber. Here, an addition-reaction type silicone rubber coating agent was used as the base material for the particulate dispersed silicone rubber constituting the second layer 11, and silicone resin particles were used as the Si-containing particles contained in the particulate dispersed silicone rubber. The rubber coating agent was adjusted such that the ratio of silicone resin particles to the second layer 11 (coating) was 55% by mass. Furthermore, the conditions for the Raman scattering measurement were the same as those in Example 1 described above.

[0123] Figure 9 (a) refers to ultraviolet radiation in the UV-C wavelength region with an illuminance of 1.2–1.3 mW / cm². 2 Raman spectra of silicone rubber after irradiation from 0 to 800 hours. In the Raman spectra, at 770 cm⁻¹... -1 Above 850cm -1 The peak with the highest intensity within the following range is taken as peak B1, at 730 cm⁻¹. -1 Above 770cm -1 The peak with the highest intensity within the following range is taken as peak B2, at 660 cm⁻¹. -1 Above 730cm -1 The peak with the highest intensity within the following range is taken as peak B3, at 600cm. -1 The above 660cm -1 The peak with the highest intensity within the following range is designated as peak B4. These Raman spectra are approximately 795 cm⁻¹. -1 Peak B1, approximately 745 cm⁻¹, originates from the yaw vibration of Si-CH₃. -1 Peak B2 is caused by the symmetric stretching vibration of CCO, and is approximately 710 cm⁻¹. -1 Peak B3 is caused by the stretching vibration of SiC2, and is approximately 620 cm⁻¹. -1 Peak B4 is caused by the stretching vibration of Si-O3.

[0124] Figure 9 (b) is an optical microscope image of the surface of the microparticle-dispersed silicone rubber after 800 hours of ultraviolet irradiation. Figure 9(b) The black dot indicates the observation position for Raman scattering measurement, which is the same as the observation position after 0 hours (no irradiation), 400 hours, and 658 hours of ultraviolet irradiation.

[0125] Figure 10 (a) is a graph showing the ratio (integral intensity ratio) of the integrated intensity of peaks B1, B2, and B4 to the integrated intensity of peak B3 in particulate dispersed silicone rubber. Figure 10 (b) is a graph showing the ratio (peak height ratio) of the peak heights of peaks B1, B2, and B4 to the peak height of peak B3. It is shown in Table 3 below. Figure 10 The values ​​of each plotted point in (a) are shown in Table 4. Figure 10 (b) The values ​​of each plotted point.

[0126] [Table 3]

[0127]

[0128] [Table 4]

[0129]

[0130] according to Figure 10 (a) Figure 10 (b) The integrated intensity ratio and peak height ratio of peak B1 begin to increase when the UV irradiation time exceeds 400 hours. This confirms that as the particulate dispersed silicone rubber deteriorates due to UV exposure, the integrated intensity ratio and peak height ratio of peak B1 increase.

[0131] The 658-hour irradiation time, one of the aforementioned ultraviolet (UV) exposure times, is the time at which particulate-dispersed silicone rubber begins to deteriorate due to UV exposure, derived from a visual test observing crack formation. The integrated intensity ratio and peak height ratio (represented by the dashed line R1) of peak B1 at 658 hours of UV irradiation are approximately 2.1 and 0.94, respectively, and can therefore be used as benchmark values ​​for diagnosing the degree of UV-induced deterioration in particulate-dispersed silicone rubber.

[0132] It should be noted that, similar to cracks in silicone rubber, cracks in particulate-dispersed silicone rubber do not necessarily occur when deterioration begins due to UV exposure. Therefore, in the aforementioned visual tests, multiple experiments were repeated, and the shortest crack initiation time was taken as the time when deterioration begins due to UV exposure. Furthermore, the fact that cracks in particulate-dispersed silicone rubber do not necessarily occur when deterioration begins due to UV exposure means that diagnosing the degree of deterioration caused by UV exposure in particulate-dispersed silicone rubber based on crack initiation is difficult.

[0133] In addition, according to Figure 10 (a) Figure 10 (b) The integrated intensity ratio and peak height ratio of peak B2 begin to increase when the UV irradiation time exceeds 400 hours. This confirms that as the particulate dispersed silicone rubber deteriorates due to UV exposure, the integrated intensity ratio and peak height ratio of peak A2 increase.

[0134] The integrated intensity ratio and peak height ratio (represented by the dashed line R2) of peak B2 after 658 hours of ultraviolet irradiation are approximately 1.3 and 0.71, respectively. Therefore, they can be used as benchmark values ​​for diagnosing the degree of degradation of particulate dispersed silicone rubber caused by ultraviolet exposure.

[0135] On the other hand, according to Figure 10 (a) Figure 10 (b) It could not be confirmed that the integral intensity ratio and peak height ratio of peak B4 increased with the increase of ultraviolet irradiation time.

[0136] (Summary of Implementation Methods)

[0137] Next, the technical ideas grasped from the embodiments described above will be described using reference numerals and the like in the embodiments. However, the symbols and the like in the following description do not limit the constituent elements in the claims to the components specifically shown in the embodiments.

[0138] [1] A quality management method for silicone rubber, comprising:

[0139] The measurement process involves irradiating the silicone rubber with a laser and measuring its Raman spectrum; and

[0140] In the diagnostic process, the degree of deterioration of the silicone rubber caused by ultraviolet exposure is diagnosed based on at least one of the intensity of the first peak attributable to the Si-O3 stretching vibration and the intensity of the second peak containing the CCO symmetric stretching vibration in the Raman spectrum.

[0141] [2] According to the quality management method of silicone rubber described in [1] above, in the diagnostic process, the effect of ultraviolet exposure on the degree of deterioration of the silicone rubber caused by ultraviolet exposure is diagnosed based on at least one of the ratio of the intensity of the first peak in the Raman spectrum to the intensity of the third peak attributable to the SiC2 stretching vibration and the ratio of the intensity of the second peak to the intensity of the third peak.

[0142] [3] According to the quality management method for silicone rubber described in [2] above, wherein,

[0143] The first peak is at 600 cm⁻¹ in the Raman spectrum. -1 The above 660cm -1The peak with the highest intensity is selected from the following range, wherein the second peak is at 730 cm⁻¹ in the Raman spectrum. -1 Above 770cm -1 The third peak is the one with the highest intensity within the following range, and it is located at 660 cm⁻¹ in the Raman spectrum. -1 Above 730cm -1 Take the peak with the highest intensity from the following range.

[0144] [4] According to the quality management method of silicone rubber described in [2] or [3] above, in the diagnostic process, the degree of deterioration of the silicone rubber caused by ultraviolet exposure is diagnosed based on whether the ratio of the integral intensity of the first peak to the integral intensity of the third peak is less than 0.23.

[0145] [5] The quality management method for silicone rubber according to any one of [2] to [4] above, wherein,

[0146] In the above diagnostic process, the degree of deterioration of the silicone rubber caused by ultraviolet exposure is diagnosed based on whether the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is less than 0.02.

[0147] [6] A quality management method for silicone rubber, comprising:

[0148] The measurement process involves irradiating silicone rubber containing dispersed Si particles with a laser and measuring its Raman spectrum; and

[0149] In the diagnostic process, the degree of deterioration of the silicone rubber containing the dispersed particles due to ultraviolet exposure is diagnosed based on at least one of the intensity of the first peak in the Raman spectrum that contains a peak belonging to the Si-CH3 yaw vibration and the intensity of the second peak that contains a peak belonging to the CCO symmetric stretching vibration.

[0150] [7] According to the quality management method of silicone rubber described in [6] above, in the diagnostic process, the degree of deterioration of the silicone rubber containing the particles due to ultraviolet exposure is diagnosed based on at least one of the ratio of the intensity of the first peak in the Raman spectrum to the intensity of the third peak attributable to the SiC2 stretching vibration and the ratio of the intensity of the second peak to the intensity of the third peak.

[0151] [8] According to the quality management method for silicone rubber described in [7] above, wherein,

[0152] The first peak is at 770 cm⁻¹ in the Raman spectrum. -1 Above 850cm -1The peak with the highest intensity is selected from the following range, wherein the second peak is at 730 cm⁻¹ in the Raman spectrum. -1 Above 770cm -1 The third peak is the one with the highest intensity within the following range, and it is located at 660 cm⁻¹ in the Raman spectrum. -1 Above 730cm -1 Take the peak with the highest intensity from the following range.

[0153] [9] According to the quality management method of silicone rubber described in [7] or [8] above, in the diagnostic process, the degree of deterioration of the silicone rubber containing the particles due to ultraviolet exposure is diagnosed based on whether the ratio of the integral intensity of the first peak to the integral intensity of the third peak is less than 2.1.

[0154]

[10] The quality management method for silicone rubber according to any one of [7] to [9] above, wherein, in the diagnostic process, the degree of deterioration of the silicone rubber in which the particles are dispersed is diagnosed based on whether the ratio of the integral intensity of the second peak to the integral intensity of the third peak is less than 1.3.

[0155]

[11] A method for manufacturing a laminated structure 1 includes: a step of forming a first layer 10 made of silicone rubber; and a step of laminating a second layer 11 made of silicone rubber dispersed with Si particles onto the first layer 10.

[0156] The manufacturing method satisfies at least one of the following first and second conditions.

[0157] First condition: The silicone rubber of the first layer 10 is silicone rubber whose degree of deterioration due to ultraviolet exposure has been diagnosed by the quality management method of silicone rubber described in any one of [1] to [5] above.

[0158] Second condition: The silicone rubber in the second layer 11 with the dispersed particles is silicone rubber whose degree of deterioration due to ultraviolet exposure has been diagnosed by the quality management method of silicone rubber described in any one of [6] to

[10] above.

[0159]

[12] A quality management method for a cable 20 or a conduit 40a, 40b, 40c, wherein the cable or conduit has an insulator made of silicone rubber, wherein the degree of deterioration of the insulator caused by ultraviolet exposure is diagnosed by any of the quality management methods for silicone rubber described in any of [1] to [5].

[0160]

[13] A quality management method for a cable 20 or a conduit 40a, 40b, 40c, wherein the cable or conduit has an insulator made of silicone rubber containing dispersed Si particles, wherein the degree of deterioration of the insulator caused by ultraviolet exposure is diagnosed by the quality management method of silicone rubber described in any one of [6] to

[10] above.

[0161]

[14] An organosilicon rubber that satisfies at least one of the following first and second conditions.

[0162] First condition: The ratio of the intensity of the first peak attributable to the Si-O3 stretching vibration to the intensity of the third peak attributable to the SiC2 stretching vibration in the Raman spectrum obtained by laser irradiation is less than 0.23.

[0163] The second condition is that the ratio of the intensity of the second peak, which includes a peak belonging to the CCO symmetric stretching vibration, to the intensity of the third peak is less than 0.02.

[0164]

[15] According to the silicone rubber described in

[14] above, wherein,

[0165] The first peak is at 600 cm⁻¹ in the Raman spectrum. -1 The above 660cm -1 The peak with the highest intensity is selected from the following range, wherein the second peak is at 730 cm⁻¹ in the Raman spectrum. -1 Above 770cm -1 The third peak is the one with the highest intensity within the following range, and it is located at 660 cm⁻¹ in the Raman spectrum. -1 Above 730cm -1 Take the peak with the highest intensity from the following range.

[0166]

[16] An organosilicon rubber, which is an organosilicon rubber with Si-containing particles dispersed therein, and satisfies at least one of the following first and second conditions.

[0167] First condition: The ratio of the intensity of the first peak, which belongs to the Si-CH3 yaw vibration, to the intensity of the third peak, which belongs to the SiC2 stretching vibration, in the Raman spectrum obtained by laser irradiation is less than 2.1.

[0168] The second condition is that the ratio of the intensity of the second peak, which includes a peak belonging to the CCO symmetric stretching vibration, to the intensity of the third peak is less than 1.3.

[0169]

[17] According to the silicone rubber described in

[16] above, wherein,

[0170] The first peak is at 770 cm⁻¹ in the Raman spectrum. -1 Above 850cm-1 The peak with the highest intensity is selected from the following range, wherein the second peak is at 730 cm⁻¹ in the Raman spectrum. -1 Above 770cm -1 The third peak is the one with the highest intensity within the following range, and it is located at 660 cm⁻¹ in the Raman spectrum. -1 Above 730cm -1 Take the peak with the highest intensity from the following range.

[0171]

[18] A laminated structure 1 has a first layer made of silicone rubber and a second layer laminated on the first layer and made of silicone rubber with dispersed Si particles, and the laminated structure satisfies at least one of the following first and second conditions.

[0172] First condition: The silicone rubber of the first layer is the silicone rubber described in

[14] or

[15] above.

[0173] Second condition: The silicone rubber in which the particles are dispersed in the second layer is the silicone rubber described in

[16] or

[17] above.

[0174]

[19] A cable 20 or a conduit 40a, 40b, 40c having an insulator formed by the laminated structure 1 described above

[18] .

[0175] The embodiments and examples of the present invention have been described above, but the present invention is not limited to the above embodiments and examples, and various modifications can be made without departing from the spirit of the invention. Furthermore, the embodiments and examples described above do not limit the invention as defined in the claims. It should also be noted that not all combinations of the features described in the embodiments and examples are necessarily necessary for solving the problems of the invention.

Claims

1. A quality management method of silicone rubber, comprising: a measurement step of measuring a Raman spectrum by irradiating a laser light to silicone rubber; and a diagnosis step of diagnosing a degree of deterioration of the silicone rubber due to ultraviolet light exposure based on at least either one of an intensity of a first peak attributed to Si-O3 stretching vibration and an intensity of a second peak containing a peak attributed to C-C-O symmetric stretching vibration in the Raman spectrum.

2. The quality management method of silicone rubber according to claim 1, wherein 3. The quality management method of silicone rubber according to claim 1 or 2, wherein 4. The quality management method of silicone rubber according to claim 1 or 2, wherein 5. The quality management method of silicone rubber according to claim 3, wherein 6. A quality management method of silicone rubber, comprising: a measurement step of measuring a Raman spectrum by irradiating a laser light to silicone rubber in which Si-containing fine particles are dispersed; and a diagnosis step of diagnosing a degree of deterioration of the silicone rubber in which the fine particles are dispersed due to ultraviolet light exposure based on at least either one of an intensity of a first peak containing a peak attributed to Si-CH3 rocking vibration and an intensity of a second peak containing a peak attributed to C-C-O symmetric stretching vibration in the Raman spectrum.

7. The quality management method of silicone rubber according to claim 6, wherein said first peak is a peak in said Raman spectrum at 600 cm -1 above 660 cm -1 the peak having the greatest intensity in the range of said second peak is a peak in said Raman spectrum at 730 cm -1 the above 770 cm -1 the peak having the maximum intensity in the following range, The third peak is a peak in the Raman spectrum at 660 cm -1 The peak with the largest intensity in the range above 730 cm -1 The peak with the largest intensity in the range below 660 cm 8. The quality management method of silicone rubber according to claim 6 or 7, wherein 9. The quality management method of silicone rubber according to claim 6 or 7, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ said first peak is a peak in said Raman spectrum at 770 cm -1 the above 850 cm -1 the peak having the maximum intensity in the following range, said second peak is a peak in said Raman spectrum at 730 cm -1 the above 770 cm -1 the peak having the maximum intensity in the following range, The third peak is a peak in the Raman spectrum at 660 cm -1 The above 730 cm -1 The peak with the maximum intensity in the following range is taken. ​ ​ 9. The quality management method of silicone rubber according to claim 6 or 7, wherein in the diagnosing step, the degree of deterioration of the silicone rubber in which the fine particles are dispersed due to ultraviolet light exposure is diagnosed based on whether or not the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 1.3 or less.

10. The quality management method of silicone rubber according to claim 8, wherein in the diagnosing step, the degree of deterioration of the silicone rubber in which the fine particles are dispersed due to ultraviolet light exposure is diagnosed based on whether or not the ratio of the integrated intensity of the second peak to the integrated intensity of the third peak is 1.3 or less.

11. A manufacturing method of a layered structure, comprising: a step of forming a first layer composed of silicone rubber; and a step of laminating a second layer composed of silicone rubber in which Si-containing fine particles are dispersed to the first layer, the manufacturing method satisfying at least either of the following first condition and second condition, the first condition: the silicone rubber of the first layer is silicone rubber whose degree of deterioration due to ultraviolet light exposure is diagnosed by the quality management method of silicone rubber according to any one of claims 1 to 5, the second condition: the silicone rubber of the second layer in which the fine particles are dispersed is silicone rubber whose degree of deterioration due to ultraviolet light exposure is diagnosed by the quality management method of silicone rubber according to any one of claims 6 to 10.

12. A quality management method of a cable or tube having an insulator composed of silicone rubber, wherein the degree of deterioration of the insulator due to ultraviolet light exposure is diagnosed by the quality management method of silicone rubber according to any one of claims 1 to 5.

13. A quality management method of a cable or tube having an insulator composed of silicone rubber in which Si-containing fine particles are dispersed, wherein the degree of deterioration of the insulator due to ultraviolet light exposure is diagnosed by the quality management method of silicone rubber according to any one of claims 6 to 10.

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