JP2008069310A - Rubber material composition and rubber molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To exert sufficiently a designed function of a rubber molded article by enhancing lubricity, paste-proof, antibacterial properties and the like, without using a lubricity coating agent, and a large quantity of an antibacterial agent. <P>SOLUTION: Polymer materials, such as a rubber material, are blended and extruded, molded, and vulcanized to form the rubber molded article. A rubber material composition containing at least 100 phr of an ethylene-α-olefine-nonconjugated polyene copolymer, 40-70 phr (at least 20 phr or more of a talc) of an alkaline inorganic filler having an arithmetic average particle size of not less than 3 μm, and an inorganic filler having a photocatalytic function or an antibacterial agent (not greater than 3 phr) blended together is used to form the rubber molded article by extruding, molding, and vulcanizing the same. A concavoconvex surface 10c derived from the alkaline inorganic filler is formed on the surface of the rubber molded article composed of the rubber material composition. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rubber material composition and a rubber molded body, and, for example, parts that require functions such as slipperiness, anti-sticking properties, and antibacterial properties (for example, bathrooms, toilets, kitchens, etc. in a high humidity atmosphere) And parts used for seals used in sliding doors of automobiles and sliding parts in automobile interiors, etc.).

  Vulcanized moldings (hereinafter referred to as rubber moldings) composed of a rubber material composition in which a polymer material such as a rubber material is blended are applied to various uses and satisfy the characteristics according to the use. It has been researched and developed to be able to. For example, the rubber molded body is applied to another member (for example, in the case of a weather strip for an automobile, for example, a door portion or a trunk portion). In the case of a weather strip used for the door portion, it corresponds to a panel or glass, and in the case of a weather strip used for a trunk portion, it corresponds to a panel; hereinafter referred to as a contact target) (contact pressure, sliding contact, etc.) Part (for example, a seal lip of a seal member; hereinafter referred to as a contact part). In this contact portion, slipperiness (for example, a characteristic that prevents a low-pitched sound from being generated by stick-slip when a rubber molded body is slid with respect to the contact target) and anti-sticking property (for example, When the rubber molded body has a low function (a characteristic that prevents the rubber molded body from deteriorating in function (degradation of functions such as sealing properties)) due to sticking between the rubber molded body and the contact object, the rubber molded body is made of, for example, a polymer elastic material. For applying a coating material (hereinafter referred to as a rubber coating material) for imparting adhesiveness and anti-sticking property to the surface of the rubber molded body (at least the surface of a portion (such as a contact portion) requiring various characteristics) Has been adopted.

  For example, in the case of a weather strip or the like that is used for automobile doors (door panels) and forms a sealing part (for example, a sealing part made of sponge rubber), the door can be opened and closed by applying rubber paint to the sealing part. At this time, the sticking between the seal portion and the door panel is prevented so that the opening and closing of the door does not become difficult. In addition, in the case where the surface of the rubber molded body slides with glass, door panels, etc., the rubber paint improves the lubricity of the surface of the rubber molded body and prevents the generation of lower sounds due to stick slip. is doing.

  In addition to the lubricity and sticking resistance, the rubber molded body as described above has begun to be studied for imparting antibacterial properties (mold prevention, etc.) against fungi and the like. For example, rubber moldings (for example, used in doors of bathrooms, toilets, kitchens, etc., and sliding parts such as automobile interiors) that are exposed to humid environments (hereinafter referred to as high humidity atmospheres). Since parts that are applied to seals used are easy to propagate molds, there is a concern about deterioration of aesthetics, health damage to the human body, and the like, and there is an increasing demand for antibacterial properties.

  As a technology for imparting slipperiness, anti-sticking properties and antibacterial properties in rubber molded products, the rubber coating material described above is applied to the surface of a rubber molded product composed of a rubber material composition containing an antibacterial agent (such as an antifungal agent). The method of applying is generally known.

  However, in the method of applying a rubber paint as described above, a layer of the rubber paint (hereinafter referred to as a paint layer) is timed due to friction (for example, local friction) with a contact object. Since the thickness decreases or peels off over time, the slipperiness, resistance to sticking and antibacterial properties cannot be maintained for a long time. In addition, the antibacterial agent affects other rubber materials and the like. For example, in the case of a rubber molded body in which a color material is blended, there is a possibility of discoloration. Furthermore, depending on the type of antibacterial agent, there is a possibility of causing a health hazard to the human body. Therefore, it is not preferable to use such an antibacterial agent in a large amount (for example, a large amount as compared with the examples described later). Have).

In addition, antibacterial paints (for example, polyorganosiloxane, paints for building materials containing photocatalytic activity) as paints for simple building materials (metals, inorganic ceramic materials, plastic molded products, plastic films, wood, paper, glass) Is known (for example, Patent Document 1). In addition, a rubber material composition (an antifungal agent (containing a halogen atom) containing an antifungal agent as a rubber molded body imparted with an antifungal property (for example, a sealing material that does not require lubricity and anti-sticking properties). Rubber moldings (for example, Patent Document 2) using 1 to 1000 hydrotalcite compounds with respect to 100) are known.
JP 11-61044 A Japanese Patent Laid-Open No. 3-131737.

  As described above, the rubber molded body can be provided with lubricity, sticking resistance, antibacterial properties, etc. without using a slippery paint or a large amount of antibacterial agents, etc. There has been a demand for a technique that can maintain the properties and the like for a long period of time and can fully exert the function of the rubber molded body.

  The present invention has been made based on the above-mentioned problems, and without using a slipping paint or a large amount of an antibacterial agent, the lubricity, sticking resistance, antibacterial property, etc. of the rubber molded body are improved, and the intended rubber molding An object of the present invention is to provide a rubber material composition and a rubber molded body that sufficiently exhibit the characteristics of the body and that have functions such as lubricity, sticking resistance, and antibacterial properties for a long period of time.

  Specifically, the invention described in claim 1 is used for a rubber molded body by extrusion molding vulcanization, and includes at least 100 phr of an ethylene-α-olefin / non-conjugated polyene copolymer and two kinds having an arithmetic average particle diameter of 3 μm or more. A rubber material composition containing the above alkaline inorganic fillers 40 phr to 70 phr and an inorganic filler having a photocatalytic function (hereinafter referred to as a photocatalytic inorganic filler), wherein the alkaline inorganic filler includes at least talc. It is characterized by.

  The invention according to claim 2 is the rubber material composition according to claim 1, wherein a silicone compound is blended in the invention according to claim 1.

The invention of claim 3 is used for a rubber molded body by extrusion molding vulcanization,
A rubber containing at least 100 phr of an ethylene-α-olefin / non-conjugated polyene copolymer, 40 phr to 70 phr of an alkaline inorganic filler having an arithmetic average particle size of 3 μm or more, 3 phr or less of an antibacterial agent, and a silicone compound The material composition is characterized in that the alkaline inorganic filler contains at least talc.

  According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the alkaline inorganic filler includes talc 20 phr or more and other alkaline inorganic fillers 20 phr or more.

  The invention according to claim 5 is a rubber molded body obtained by extrusion-molding and vulcanizing any one of the rubber material compositions according to claims 1 to 4, and is derived from an alkaline inorganic filler on the surface side of the rubber molded body. An uneven surface (that is, an uneven surface caused by the particle size, blending amount, etc. of the alkaline inorganic filler) is formed.

  As described above, at least 100 phr of ethylene-α-olefin / non-conjugated polyene copolymer, two or more kinds of alkaline inorganic fillers having an arithmetic average particle diameter of 3 μm or more, 40 phr to 70 phr (at least 20 phr or more is talc), and photocatalytic inorganic In a rubber material composition containing a filler or an antibacterial agent (3 phr or less (for example, a small amount compared to Patent Document 2)), the inorganic filler having the photocatalytic function and the antibacterial agent itself have an antibacterial action. In addition, the growth of bacteria is suppressed (antibacterial action is promoted) due to the characteristics (alkaline) of the alkaline inorganic filler itself. Therefore, sufficient antibacterial properties can be obtained without using a large amount of antibacterial agent.

When the photocatalyst inorganic filler is blended, a photocatalytic reaction can occur in the rubber molded body. For example, when the rubber molding is present in an environment where light of a specific wavelength (for example, ultraviolet light of 400 nm or less) can be irradiated (in an environment where the light of sunlight or lighting equipment can be irradiated), the light of the specific wavelength As a result, holes (h ⁺ ) and excited electrons (e ⁻ ) are generated on the surface of the photocatalyst inorganic filler to cause a photocatalytic reaction. When the holes react with oxygen in the atmosphere (reduction of oxygen), oxygen radicals having an antibacterial action are generated.

Among the above alkaline inorganic fillers, talc (3MgO · 4SiO ₂ · H ₂ O) has a layered structure (three-layer structure; silicic acid / Mg having silicic acid / silicic acid) and each layer is easily peeled off (sliding properties, etc.) Have In the case of a rubber material composition simply blended with a polymer material and talc, kneading and the like may be difficult (aggregation properties may be reduced due to the property that each layer is easily peeled), but other (other than talc) When an alkaline inorganic filler coexists, kneading is facilitated.

  In general, for example, in the case of a rubber molded body made of an acidic inorganic filler (for example, an acidic functional group attached like carbon) or a polymer material, so-called bound rubber (a rubber component bonded to carbon) Is generated, and the slipperiness or the like can be changed according to the amount of the bound rubber. On the other hand, when the alkaline inorganic filler is used as described above, since the generation of bound rubber as described above is suppressed, the lubricity and the like are not affected.

  In addition, a rubber molded body obtained by extrusion molding and vulcanizing the rubber material composition has a portion where a large amount of ethylene-α-olefin / non-conjugated polyene copolymer component is locally formed in the rubber molded body, In order to cause shrinkage or the like at that portion, an uneven surface derived from an alkaline inorganic filler having a surface roughness due to the particle size, blending amount, etc. of the alkaline inorganic filler is formed. Thereby, the contact area of the said rubber molded object and contact object becomes small. In the case of a method of applying a sliding paint for rubber, a phenomenon such as peeling may occur due to friction between the paint layer and the contact object, but when an uneven surface derived from an alkaline inorganic filler is formed Such a phenomenon is less likely to occur.

  When a silicone compound is blended, the silicone compound bleeds on the surface of the rubber molded body (such as an uneven surface derived from an alkaline inorganic filler). With this bleed product, the properties (slidability, sticking resistance, water repellency, etc.) of the silicone compound itself can be exhibited on the surface of the rubber molded body.

  The amount of the ethylene-α-olefin / non-conjugated polyene copolymer, alkaline inorganic filler, silicone compound, photocatalyst inorganic filler, antibacterial agent, etc. is the desired amount of rubber material composition or rubber molded product. It is preferable that the characteristics are not impaired.

  For example, when the blending amount of the ethylene-α-olefin / non-conjugated polyene copolymer and the alkaline inorganic filler is outside the range shown in the present invention, the kneading processability of the rubber material composition, the extrusion moldability, and the rubber molded body Properties (sliding, sticking resistance, etc.) may be reduced.

  If the blending amount of the alkaline inorganic filler is too small, the kneading processability and extrusion moldability of the rubber material composition is impaired, and if it is excessive, the uneven surface derived from the alkaline inorganic filler of the rubber molded body may not be formed. is there.

  When the silicone compound is excessively blended, the rubber molded body may be melt-bonded (for example, melt-bonding with a thermoplastic elastomer or melt-bonding when a rubber member is injection-molded). It can be difficult. If the viscosity of the silicone compound is too low, kneading processability and the like may be impaired. If the viscosity of the silicone compound is too low (for example, about 100 cSt), the kneading processability of the rubber material composition may be impaired.

  In the softening agent, when the softening agent has adhesiveness, there is a possibility that the sticking resistance of the rubber molded body is impaired when it is excessively blended.

  When the foaming agent is blended, if the blending amount is excessive, the specific gravity of the rubber molded body becomes too small (for example, compared with the specific gravity of a rubber molded body such as a general automobile weather strip). Thus, if the specific gravity of the rubber molded body is too small, the number of foamed cells inside the rubber molded body increases, and when a silicone compound is blended, bleeding of the silicone compound is inhibited, and the bleeding speed is too slow. There is a possibility that.

  In addition to the above-mentioned materials, for example, various materials used in the technical field of rubber moldings by general extrusion molding vulcanization may be appropriately blended. It is preferable that the properties of the article and the rubber molded body are not impaired.

  For example, when using vulcanizing agents, vulcanization accelerators, vulcanization accelerating aids, etc., if the blending amount is too small, the vulcanization progresses slowly, and if the blending amount is too large, the Bloom phenomenon may occur. There is.

  According to the first and third aspects of the invention, the rubber material composition has sufficient kneadability and extrudability, and can be obtained, for example, by extrusion vulcanization of the rubber material composition as in the fifth aspect of the invention. In a rubber molded product, sufficient functions such as slipperiness, resistance to sticking and antibacterial properties are maintained. Thereby, the characteristic of the target rubber molded object can fully be exhibited.

  Further, according to the invention described in claim 2, for example, in the rubber molded body as in the invention described in claim 5, functions such as lubricity and anti-sticking property are improved according to the blending amount of the silicone compound.

  Furthermore, according to the invention described in claim 4, the kneading processability and extrusion moldability of the rubber material composition are improved. For example, in a rubber molded article such as the invention described in claim 5, good slipping and anti-sticking properties are achieved. Functions such as sexuality and antibacterial properties are maintained more stably.

  Hereinafter, a rubber material composition and a rubber molded body in an embodiment of the present invention will be described in detail with reference to the drawings.

  The present embodiment relates to a rubber molded body obtained by blending a polymer material such as a rubber material (for example, ethylene-α-olefin / non-conjugated polyene copolymer) and extrusion molding vulcanization, and at least the polymer The present invention relates to a rubber material composition in which a material 100 phr, an alkaline inorganic filler 40 phr to 70 phr having an arithmetic average particle size of 3 μm or more, and a photocatalytic inorganic filler or an antibacterial agent (3 phr or less) are blended.

  The alkaline inorganic filler includes at least talc (preferably includes 20 phr or more of talc and 20 phr or more of another alkaline inorganic filler).

  In general extrusion vulcanization, after the rubber material composition is discharged from the die of the extrusion molding machine, the discharged product (extruded product) is in a free state (unlike mold molding, the pressure on the discharged product is almost The target rubber molding is obtained by carrying out a crosslinking reaction in a non-applying state. For example, as a general rubber molded body (rubber molded body obtained by extruding and vulcanizing a rubber material composition), an alkaline inorganic filler having an average particle size of less than 3 μm is added to an ethylene-α-olefin / non-conjugated polyene copolymer. When blended, or when blended more than 70 phr even at 3 μm or more, as shown in the structural model diagram of FIG. 1A, the surface of the rubber molded body 10 (a flat surface indicated by reference numeral 10a in the figure) is It will be relatively flat.

  In addition, when the silicone compound is mix | blended in the rubber molding 10 as shown to FIG. 1A, a silicone compound bleeds to the flat surface 10a as shown to FIG. 1B, and the bleed | bleed thing (in the figure, code | symbol 10b) The slidability and sticking resistance can be obtained by the above, but the bleed material of the flat surface 10a is caused by, for example, wiping by the assembling work of the rubber molded body 10 or sliding with the contact target of the application target. 10b may be easily removed. In this case, the bleed of the silicone compound occurs again to obtain lubricity, sticking resistance, etc., but it takes a predetermined time to reach the bleed.

  On the other hand, as in this embodiment, a rubber material composition in which 40 to 70 phr of an inorganic inorganic filler having an average particle size of 3 μm or more is blended with the ethylene-α-olefin / non-conjugated polyene copolymer is extruded and vulcanized. In the case of the rubber molded body, as shown in the structural model diagrams of FIGS. 1C and 1D (partially enlarged view of FIG. 1C), the irregularities derived from the alkaline inorganic filler having a small surface roughness with respect to the surface of the rubber molded body 10 A surface (hereinafter simply referred to as an uneven surface) 10c is formed. This is because the blending amount of the alkaline inorganic filler having a large particle size is relatively small, so that a portion where the ethylene-α-olefin / non-conjugated polyene copolymer component is locally formed in the rubber molded body 10 is formed. This is considered to be because the portion easily contracts.

  As in the present embodiment, if the rubber molded body is provided with the uneven surface 10c, the contact area with the contact target of the application target becomes small, so that good sticking resistance can be obtained. Moreover, since at least a part of the alkaline inorganic filler is talc, good slipperiness can be obtained due to the characteristics of the talc itself (characteristics in which each layer easily peels off in a layered structure). Furthermore, the growth of bacteria is suppressed by the characteristics (alkaline) of the alkaline inorganic filler itself. In the present embodiment, the sticking resistance and slipperiness are stably maintained for a long period of time, unlike the conventional method in which sticking resistance and slipping are obtained by a paint layer.

  In the present embodiment, when a silicone compound is blended, the silicone compound bleeds on the concavo-convex surface 10c as shown in FIG. 1E, and the bleed product 10b is wiped off by, for example, assembling the rubber molded body. When sliding or the like with the contact target in the application target is performed, as shown in FIG. 1F, the bleed object 10b particularly on the outer peripheral side of the concave / convex surface 10c (particularly, on the outer peripheral side of the convex portion of the concave / convex surface 10a). May be easily removed, but the bleed material on the inner side of the uneven surface 10c (particularly, the concave portion of the uneven surface 10c) remains difficult to remove.

  As shown in FIG. 1F, when there is a region 10d from which the bleed material 10b is removed (hereinafter referred to as a removal region) 10d in the concavo-convex surface 10c, the remaining bleed material (at least a part of the bleed material) is in the removal region. Moving. Further, in the concave and convex surface 10c, particularly in the concave portion, the amount of the bleed product 10b is further increased due to a change with time in the remaining bleed product 10b, and as a result, the bleed product 10b easily moves to the removal region 10d. That is, even if the bleed object 10b is removed as in the removal region 10d on the uneven surface 10c and the state shown in FIG. 1F is obtained, the state shown in FIG. 1E (G) is likely to return.

  As shown in FIGS. 1E to G, when the bleed product 10b is present, the bleed product 10b maintains better slipperiness, anti-sticking property and the like stably for a long period of time. Moreover, since water repellency is obtained by the silicone compound, better antibacterial properties are stably maintained for a long time.

  In the rubber material composition and rubber molded body of the present embodiment, an ethylene-α-olefin / non-conjugated polyene copolymer, an alkaline inorganic filler, a photocatalytic inorganic filler, or a small amount of an antibacterial agent (an antifungal agent, etc.) as shown below In addition to various additives such as silicone compounds, foaming agents, softening agents, vulcanizing agents, vulcanization accelerating aids, vulcanization accelerating aids, processing aids, etc. It may be a thing.

[Ethylene-α-olefin / non-conjugated polyene copolymer]
In the ethylene-α-olefin / non-conjugated polyene copolymer, as the α-olefin, for example, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene Etc., preferably propylene. Of course, a plurality of these α-olefin groups may be selected and used in combination, for example, propylene and 1-butene.

  In addition, the polyene copolymer is a cyclic non-conjugated polyene such as 5-ethylidene-2-norbornene, dicyclopentadiene, 5-vinyl-2-norbornene, norbornadiene, methyltetrahydroindene, 1,4 hexadiene, 7 -Methyl-1,6-octadiene, 4-ethylidene-8-methyl-1,7-nonadiene, 4-ethylidene-1,7undecadiene, 4,8-dimethyl-1,4,8-decatriene, etc. Those that are non-conjugated polyenes. Each of these non-conjugated polyenes may be used alone or in combination of two or more, and the constitutional unit (content ratio of non-conjugated polyene in the ethylene-α-olefin / non-conjugated polyene copolymer) is, for example, 1 wt% to 20 wt%. And preferably 1 wt% to 15 wt%, more preferably 5 wt% to 11 wt%. As such an ethylene-α-olefin / non-conjugated polyene copolymer, for example, Esprene 7456 manufactured by Sumitomo Chemical Co., Ltd. can be applied.

[Alkaline inorganic filler]
As the alkaline inorganic filler, those having an average particle diameter (arithmetic average particle diameter) of 3 μm or more (preferably 3 μm to 10 μm) are used in a blending amount of 40 phr to 70 phr. Further, talc is used for at least 20 phr or more of 40 phr to 70 phr of the alkaline inorganic filler.

  Specific examples of the alkaline inorganic filler other than talc include calcium carbonate, magnesium carbonate, swellable mica, smectite, potassium titanate whisker hydrotalcite compounds, and the like. In addition, it can be suitably applied to fillers surface-treated with an alkaline compound, such as aminosilane-treated clay, amine-treated sepiolite, alkali-treated silica and the like as in the above specific examples.

  Even when 40 phr to 70 phr of an alkaline inorganic filler having an average particle size of less than 3 μm is used, the uneven surface is not formed on the surface of the rubber molded body as in this embodiment. Even when the average particle size is 3 μm or more, if the blending amount is less than 40 phr, the kneading processability and extrusion moldability of the rubber material composition are significantly lowered. For example, when the blending amount of talc is less than 20 phr, the lubricity of the rubber molded body is particularly lowered and the antibacterial property is also lowered. When the blending amount of the alkaline inorganic filler other than talc is less than 20 phr, the kneading processability and extrusion moldability are lowered, and the antibacterial property can also be lowered. Furthermore, when the average particle size is too large (for example, in the case of more than 10 μm), there is a possibility that the desired physical properties cannot be obtained in the intended rubber molded product because the rubber material composition is dispersed unevenly. is there.

[Photocatalyst inorganic filler]
Examples of the photocatalytic inorganic filler include TiO ₂ , ZnO, SrTiO ₃ , CdS, GaP, InP, GaAs, BaTiO ₃ , K ₂ NbO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ , WO ₃ , SnO ₂ , Compounds such as Bi ₂ O ₃ , NiO, Cu ₂ O, SiC, SiO ₂ , MoS ₂ , InPb, RuO ₂ , and CeO ₂ can be applied. Further, the present invention can also be applied to compounds in which a metal or metal oxide such as Pt, Rh, RuO ₂ , Nb, Cu, Sn, or NiO is added to the above compound (known compounds). Preferably, a metal oxide such as TiO ₂ , titanium peroxide (peroxotitanic acid), ZnO, SrTiO ₃ , Fe ₂ O ₃ , WO ₃ , SnO ₂ , Bi ₂ O ₃ is applied. In particular, TiO ₂ is more suitable because it is a versatile metal oxide that has a high band energy gap and is scientifically stable.

  The photocatalyst inorganic filler as described above is used in a blending amount that does not impair the properties of the target rubber material composition or rubber molded body, and is, for example, 1 phr to 50 phr, preferably 10 phr to 30 phr. In particular, when a titanium-based compound is used, if the blending amount exceeds 30 phr, white powder (white powder due to the titanium-based compound) is generated on the surface of the rubber molded body when exposed to a high temperature atmosphere, for example. Although the appearance can be changed, the slipperiness and sticking resistance are improved.

[Antimicrobial agent]
Examples of the antibacterial agent include antifungal agents, and commercially available inorganic and organic agents can be applied. Specific examples of inorganic antibacterial agents include boron oxide, boric acid, silver compounds (eg, silver zeolite compounds, silver oxide, silver fluoride, silver chloride, silver bromide, silver nitrate, silver sulfate, silver acetate, silver lactate, Silver chlorate, silver picrate, protein silver, colloidal silver, silver salt of carboxylic acid, alkyl ester of phosphoric acid (or phosphorous acid) (or silver salt of phenyl ester, alkylphenyl ester), etc.) Can be mentioned. Specific examples of the organic antibacterial agent include imidazole, thiazole, pyridine, bromide and the like, and representative examples include thiazolylbenzimidazole (TBZ manufactured by Calgon), thiazolylsulfamide compounds. (KB9 manufactured by Taimeitec Co., Ltd.), 2-pyridinepiol-1-oxide zinc (~ Zpt manufactured by KK) is generally known.

  The antibacterial agent as described above is used in a small amount in such an amount that does not impair the properties of the intended rubber material composition and rubber molded body, and preferably 3 phr or less. When the blending amount is more than 3 phr, the kneading processability and extrusion moldability of the rubber material composition are lowered, and particularly the chemical resistance (discoloration resistance) and sticking resistance of the rubber molded body can be lowered. In addition, there are concerns about the effects of health damage on the human body.

[Silicone compound]
Examples of the silicone compound include silicone oils such as dimethyl silicone oil, methylphenyl silicone oil, and silicone gel (so-called gummy silicone). More specifically, for example, KF96, KF50, KE76BS manufactured by Shin-Etsu Chemical Co., Ltd., TSE3051 manufactured by GE Toshiba Silicone Co., etc., and the like can be mentioned. Moreover, each said silicone compound may use any 1 type, and may use it combining several types of things.

  Furthermore, it is preferable to use the silicone compound as described above in such a compounding amount that does not impair the properties of the intended rubber material composition or rubber molded article. More preferably, it is 3-30 phr, More preferably, it is 5-20 phr. If the blending amount is more than 30 phr, the kneadability, extrusion moldability and the like are lowered, and if it is less than 3 phr, the lubricity effect by the silicone compound may not be sufficient.

[Foaming agent]
As said foaming agent, an organic type foaming agent, a thermal expansion capsule, etc. can be applied suitably. Specific examples of the organic foaming agent include 4,4-oxybisbenzenesulfonyl hydrazide (OBSH), azodicarbonamide (ADCA), dinitrosopentamethylenetetramine (DPT), azobisisobutyronitrile (AIBN), para Examples include toluenesulfonyl hydrazide (TSH), hydrazodicarbonamide (HDCA), and barium azocarboxylate. This organic foaming agent is preferably used to such an extent that it does not impair the properties of the intended rubber material composition or rubber molding (for example, 0 to 10 phr). In addition to the above organic foaming agents, foaming aids such as urea derivatives, salicylic acid, phthalic acid, and stearic acid may be used.

  As a specific example of the thermally expanded capsule, for example, a liquid (for example, low boiling point hydrocarbon or chlorinated hydrocarbon) capable of generating a gas by heating is filled in a shell wall (for example, spherical shell wall) of a thermoplastic resin. (Thermally expandable thermoplastic resin particles) having a true specific gravity of 0.1 or less, a particle size (median diameter) of 5 μm to 100 μm, and the liquid is not less than the expansion start temperature (for example, 120 ° C. to 150 ° C.) Liquid-encapsulated thermoplastic resin particles that expand by heating at a temperature of (for example, heating at the vulcanization temperature) and form a thermal expansion cell (for example, a thermal expansion cell of 30 μm to 300 μm) in the target rubber molded body. It is done.

  When the expansion start temperature of the thermal expansion capsule is sufficiently lower than the vulcanization temperature of the target rubber molded body (for example, when the peak temperature of the vulcanization temperature is about 170 ° C., about 120 ° C. to 150 ° C.) Since a vulcanized rubber molded body is obtained after the structure by the thermal expansion cell is formed during the vulcanization process, even if there is a variation in vulcanization temperature that may occur in the production process, the rubber molding There is almost no variation in the specific gravity of the body. In other words, sponge rubber can be produced with a stable specific gravity.

  Moreover, as a component of the thermoplastic resin which comprises the shell wall of the said thermal expansion capsule, Preferably a (meth) acrylonitrile polymer and a polymer containing many (meth) acrylonitrile are mentioned, Examples of monomers (so-called counterpart monomers; comonomers) include monomers such as vinyl halides, vinylidene halides, styrene monomers, (meth) acrylate monomers, vinyl acetate, butadiene, vinyl pyridine, and chloroprene.

  The shell wall is preferably uncrosslinked, but may be crosslinked with a general crosslinking agent such as divinylbenzene or ethylene glycol di (meth) acrylate. Examples of the liquid filled in the thermally expanded capsule include hydrocarbons such as n-pentane, isopentane, neopentane, butane, isobutane, hexane, and petroleum ether, and chlorine such as methyl chloride, dichloroethylene, trichloroethane, and trichloroethylene. Hydrocarbons.

  As a further specific example of the thermal expansion capsule, H770D, H850D, and M430, which are the same series, as well as Die Form H750D manufactured by Dainichi Seika Kogyo Co., Ltd. can be suitably used. Further, for example, Matsumoto Microspheres F80S-D, F85D, F100D, F105-D, F82-D manufactured by Matsumoto Yushi Co., Ltd., EXPANCEL091DU-80, 092DU-120 manufactured by EXPANSEL, Sweden, etc. are applied. You can also It is preferable to use the thermal expansion capsule so as to have a desired specific gravity (for example, use about 1.0 phr to 15 phr) within a range that does not impair the properties of the target rubber material composition and rubber molded body. .

  When such a thermally expanded capsule is added to a polymer material such as an ethylene-α-olefin / non-conjugated polyene copolymer, in order to prevent scattering of the thermally expanded capsule and improve dispersibility, It may be used after being mixed (master batch) with a material to be used (for example, a polymer elastic body, thermoplastic resin, softener, inorganic filler or the like, or a plurality of them). For example, oil content products, ethylene vinyl alcohol (EVA), polyethylene (PE) and the like containing thermally expanded capsules are generally commercially available.

  When the thermally expanded capsule is used after previously mixed with other materials used, the mixing ratio of the foaming agent is adjusted to 10 wt% to 99 wt%, preferably 10 wt% to 50 wt%. Moreover, any one kind of the above-mentioned thermally expanded capsules may be used, or a plurality of kinds may be used in combination.

  As the blending amount of the foaming agent increases, the specific gravity of the rubber molded body decreases. However, if the specific gravity is too small, the bleed speed of the silicone compound decreases when the silicone compound is blended. Since it has a tendency, it is preferable to adjust the blending amount as appropriate (for example, to ensure a specific gravity of 0.3 or more).

[Softener]
Examples of the softener include petroleum softeners such as process oil, paraffinic oil, lubricating oil, liquid paraffin, petroleum asphalt, and petroleum jelly, coal tar softeners such as coal tar and coal tar pitch, and castor oil. , Fatty oil softeners such as linseed oil, rapeseed oil and coconut oil. Of these softeners, petroleum softeners are preferable, and paraffin oil is more preferable. The softening agent as described above is used in a blending amount that does not impair the properties of the intended rubber material composition or rubber molded body, and is, for example, 100 phr or less.

[Vulcanizing agent]
Examples of the vulcanizing agent include sulfur, and it is used in a blending amount that does not impair the properties of the intended rubber material composition or rubber molded body, and preferably about 0.5 phr to 2 phr.

[Vulcanization accelerator]
Examples of the vulcanization accelerator include thiazole type, thiuram type, sulfenamide type, guanidine type, thiourea type, and dithiocarbamic acid type, which impair the characteristics of the intended rubber material composition and rubber molding. It is used in a blending amount that is not excessive, preferably about 2 phr to 8 phr.

[Vulcanization acceleration aid]
Examples of the vulcanization acceleration aid include zinc oxide (zinc white), zinc carbonate, magnesium oxide, calcium hydroxide, zinc monoxide and the like, preferably zinc oxide and magnesium oxide. These vulcanization accelerating aids are used in a blending amount that does not impair the properties of the intended rubber material composition or rubber molded body, and preferably about 5 phr.

[Processing aid]
Examples of the processing aid include higher fatty acids such as stearic acid, ricinoleic acid, palmitic acid and lauric acid, esters of the higher fatty acids, salts of higher fatty acids such as stearic acid, and other rubber moldings. A compound that is treated as a processing aid in the technical field may be used. These processing aids are used in an amount so as not to impair the properties of the intended rubber material composition and rubber molded body, preferably about 5 phr, more preferably 3 phr or less.

[Other additives]
In addition to the above-mentioned various additives, dehydrating agents, antioxidants, anti-aging agents, heat stabilizers, light stabilizers, UV absorbers, neutralizers, lubricants, anti-clouding agents, anti-blocking agents, slip agents, Dispersant, flame retardant, antistatic agent, conductivity imparting agent, tackifier, crosslinking agent, crosslinking aid, metal deactivator, molecular weight regulator, antibacterial / antifungal agent, fluorescent whitening agent, sliding property Improving agent, colorant (such as titanium oxide), metal powder (such as ferrite), glass fiber, inorganic fiber (such as metal fiber), carbon fiber, organic fiber (such as aramid fiber), composite fiber, glass balloon, glass flake, graphite , Carbon nanotube, fullerene, barium sulfate, fluororesin, filler polyolefin wax (polymer beads, etc.), cellulose powder, rubber powder, recycled rubber, etc. Combined, it may be used as appropriate according to the rubber material composition and rubber molded article of interest.

[Production method]
The above-mentioned ethylene-α-olefin / non-conjugated polyene copolymer, alkaline inorganic filler, photocatalyst inorganic filler or antibacterial agent, and various additives such as silicone compounds depending on the intended use For example, various sealed kneaders such as a tangential mixer, a meshing mixer, and a kneader, a continuous twin-screw extrusion kneader, an open roll, and the like can be appropriately applied. When the rubber material composition is subjected to extrusion molding vulcanization (for example, extrusion molding vulcanization at 200 ± 40 ° C.) to obtain a target rubber molding, for example, a continuous hot air vulcanizer (HAV), A high frequency vulcanizer (UHF) and other general vulcanizers can be applied. Further, a combination of the above-mentioned various devices (for example, a combination of continuous hot air vulcanization and high-frequency vulcanization) can also be suitably applied.

  Next, various rubber material compositions (rubber compounds S1 to S14 (examples) and P1 to P13 (comparative examples) described later) were prepared based on the present embodiment, and the processability of these rubber material compositions and The physical properties and the like of rubber molded bodies (samples GS1 to GS14 (examples) and GP1 to GP13 (comparative examples) described later) were examined.

  First, 100 phr of ethylene-propylene-5-ethylidene-2-norbornene (Esprene 7456, manufactured by Sumitomo Chemical Co., Ltd.) was used as a polymer material and masticated in a closed mixer. Thereafter, calcium carbonate (NN # 500, SS # 80, NITREX23P, manufactured by Nitto Flour Chemical Co., Ltd.), talc (high filler # 5000PJ, high filler # 12, manufactured by Toshinsei Co., Ltd.) as alkaline inorganic fillers for the kneaded product. High filler # 7) is 0 to 50 phr each, clay (manufactured by Angelhard Co.) as acidic inorganic filler, silica (manufactured by Nippon Silica Co., Ltd.) is 0 to 30 phr each, and titanium oxide (ST- from Ishihara Sangyo Co., Ltd. as photocatalyst inorganic filler) K) from 0 to 40 phr, two antifungal agents as antibacterial agents (silver zeolite compound (Irgagaard F5000 manufactured by Ciba Specialty Chemicals); hereinafter referred to as antibacterial agent A), benzimidazole compound, haloalkylthiol compound, thiazole Mixed fungicides containing compounds (timeme 0 to 4 phr of KB9 manufactured by Tech Co., hereinafter referred to as antibacterial agent B)), and 0 as silicone oil (silicone oil having a viscosity (25 ° C.) of 1000 cSt and 100000 cSt (KE76BS manufactured by Shin-Etsu Chemical Co., Ltd.)) 10 phr, 30 phr of paraffin oil (PW380 manufactured by Idemitsu Co., Ltd.) was added as a softening agent, and the mixture was kneaded with a 5 L hermetic kneader for 5 minutes.

  In this example, heavy calcium carbonate (calculated as calcium carbonate) having an arithmetic average particle size of 5.0 μm (pH 9.3 (NN # 500)) and 3.0 μm (pH 9.5 (SS # 80)) (hereinafter, respectively) Heavy coal cal (referred to as 5.0 μm, 3.0 μm) and fine calcium carbonate (hereinafter referred to as fine coal cal as 0.90 μm) having an arithmetic average particle size of 0.90 μm (pH 9.7 (NITOREX23P)). As the talc, the arithmetic average particle size is 1.8 μm (pH 10.1 (high filler # 5000PJ)), 3.0 μm (pH 9.6 (high filler # 12)), 5.0 μm (pH 9.5 (high filler # 12)). 7)) (hereinafter referred to as talc 1.8 μm, 3.0 μm and 5.0 μm, respectively), and 1.5 μm (pH 5.2) and 4.0 μm (pH 6.0) as clay and silica. (Hereinafter referred to as clay 1.5 μm and silica 4.0 μm, respectively) (each corresponding to a desired arithmetic average particle diameter was selected from the material lot). In addition to the various materials described above, 1 phr of stearic acid is added as a processing aid, and 3 phr of zinc oxide is added as a vulcanization acceleration aid, followed by kneading.

  The arithmetic average particle diameter is an average particle diameter (“average particle diameter (μm)” = (6 / specific gravity) × specific surface area × calculated by a laser diffraction formula (SALD-100 manufactured by Shimadzu Corporation). 10,000). The pH value of each filler such as heavy calcium carbonate was measured according to JIS K5101, and a suspension obtained by adding water to the target filler was boiled for 5 minutes. Then, it is set as the pH value which concerns on the supernatant liquid produced by standing to cool to room temperature level.

  Thereafter, the kneaded product obtained with the above-mentioned closed kneader is taken out, and while kneading with an open roll machine, 0 to 1 phr of thermal expansion capsule (Daifoam H750D, manufactured by Dainichi Seika Kogyo Co., Ltd.), vulcanization acceleration By adding 5 phr of thiazole, thiuram and sulfenamide as agents, adding 1 phr of sulfur as a vulcanizing agent (added after the kneaded material is wound on a roll), and mixing (blending) for a predetermined time, As shown in Table 1 described later, rubber compounds (ribbon-like unvulcanized rubber compounds) S1 to S14 and P1 to P13 having various compositions were obtained.

  Next, in each of the rubber compounds S1 to S14 and P1 to P13, extrusion molding is performed using an extrusion molding machine for a rubber molded body (having a die shape such that a molded body shown in FIG. 2 described later is obtained). 2 by adjusting the screw rotation speed with an extrusion extruder, and then vulcanizing the extruded product with a continuous hot-air vulcanizer (at a temperature of 200 ° C. for 10 minutes). As shown in FIG. 2, a rubber molded body (having a height of 20 mm) provided with a tube portion (tube with a thickness of 2 mm) 22 having a substantially circular cross section with respect to a substantially flat base portion (a base portion with a thickness of 2 mm and a width of 25 mm) 21. Rubber molded body) samples GS1 to GS14 and GP1 to GP13 (reference numeral 20 in the figure) were prepared.

  Processability (kneading processability, extrusion moldability) of each rubber compound S1 to S14 and P1 to P13 produced as described above, and surface roughness and lubricity (friction coefficient) of each sample GS1 to GS14 and GP1 to GP13 ), Anti-sticking property (sticking force), antibacterial property, and chemical resistance (discoloration resistance) were measured by the following methods, and the measurement results are shown in Table 3 below. In addition, in the items of comprehensive evaluation in Table 3 to be described later, symbols “」 ”,“ ○ ”,“ △ ”, and“ × ”indicate seal parts such as weather strips used for automobile doors (antibacterial properties). The seal part provided; hereinafter referred to as an antibacterial seal part) indicates a case where it is considered difficult to apply, when it can be applied satisfactorily, when it can be applied satisfactorily, when possible.

[Kneading processability]
Each rubber compound was kneaded with an open roll machine having a 14-inch roll and a distance between the rolls set to 5 mm, and the wrapping property of the rubber compound with respect to each roll was observed. In addition, in the item of kneading processability in Table 3 to be described later, the symbol “◎” indicates a case where the rubber compound easily enters between the rolls and is well adhered to the rolls, and the symbol “◯”. Indicates the case where the rubber compound has sufficiently penetrated between the rolls and wound tightly around the roll, and the symbol “x” indicates that the rubber compound does not adhere to each roll and hangs down or is cut in the middle It shall be shown. The symbol “Δ” indicates that the rubber compound is less likely to enter between the rolls than in the case of the symbol “◯”, but the rubber compound is wound so as to be in close contact with the roll over time.

[Extrudability]
Extrusion for 1 minute in each rubber compound (rubber compound adjusted to a temperature of 60 ± 5 ° C. at the time of extrusion) by an extruder with a diameter of 75 mm and a rotation speed set to 15 rpm. The rubber molded bodies (samples 20) having the shapes shown in FIG. 2 were obtained.

  This extrusion molding was repeated 100 times for each rubber compound, and the mass (g) of the extruded product (unvulcanized product) discharged from the extruder for each extrusion molding was weighed as a discharge amount. And the dispersion | variation (%) of discharge amount was computed by the following formula for every rubber compound.

  “Dispersion of discharge amount” (%) = ((“maximum discharge amount” − “minimum discharge amount”) / average discharge amount) × 100.

[Surface roughness]
The sample 20 was punched into a rectangular flat plate shape (5 mm × 100 mm × 2 mm) to prepare sample pieces, and the surface of these sample pieces was wiped off with alcohol, and then a surface roughness meter (manufactured by Kosaka Laboratory Co., Ltd.). The surface roughness (ten-point average roughness (Rz)) of each sample piece was measured by a ten-point average method (a method based on JIS-B0601) using Surfcoder SE30D). In addition, the stylus tip radius of 2 μm was used as the stylus of the surface roughness meter.

[Lubricity (coefficient of friction)]
As shown in FIG. 3A (schematic diagram), the sample 20 is punched into a rectangular flat plate shape (5 mm × 100 mm × 2 mm) to prepare a sample piece 30, and the surface of the sample piece 30 is wiped off with ethanol. And a friction coefficient measuring machine (HEIDON-14D manufactured by Shinto Kagaku Co., Ltd.) on a support base (test base) 31. After that, the weight member 32 which is composed of R50 spherical glass and applied with a load of 0.98 N is placed on the sample piece 30 (the R50 spherical side is placed), and the weight member 32 is placed in the horizontal direction (sample The static friction coefficient (μs) and the dynamic friction coefficient (μd) were measured by sliding at a speed of 1000 mm / min (sliding while contacting the sample piece 30) with respect to the longitudinal direction of the piece 30; Note that a stylus tip radius of 2 μm was used as the stylus of the friction coefficient measuring machine.

[Attachment resistance]
As shown in FIGS. 4A (plan view), B (side view), and C (operation diagram), the sample 20 is punched into a rectangular flat plate shape (5 mm × 50 mm × 2 mm) to produce two sample pieces 40. The surface of each sample piece 40 was cleaned (wiped off) with ethanol, and then a double-sided adhesive tape was bonded to a rectangular flat plate (2 mm × 110 mm × 70 mm) stainless steel plate (SUS plate) 41 at a distance of 60 mm. It was fixed with an agent (surface of 5 mm × 50 mm was fixed).

  Further, a white melamine coating plate 42 having a rectangular flat plate shape (similar to the stainless steel plate 41 and having a thickness of 1.0 mm to 1.5 mm) is placed on the sample piece 40 so as to cover each sample piece 40. Place a total of 49N (24.5N × 2) weight members 43 on the coating plate 42 and apply a load (while applying a load to the portion of the coating plate 42 where the sample piece 40 is located). And left in a high-temperature bath (in an atmosphere at 80 ° C.) for 24 hours.

Thereafter, the weight member 43 is removed (removed immediately before the measurement), and a jig 44 having a substantially L-shaped longitudinal section is interposed between the stainless steel plate 41 and the coating plate 42 (and between each sample piece 40), With the inner corner side of the jig 44 engaged with the end of the coating plate 42 and the stainless steel plate 41 fixed, the jig 44 is moved in the horizontal direction (for each of the fixed specimen pieces 40). When the coated plate 42 and the sample piece 40 are completely peeled by pulling at a speed of 50 mm / min with respect to the longitudinal direction (arrow direction shown in the drawing) (that is, pulling the coated plate 32 through the jig 34). The maximum load generated (unit: N / 5 cm ² ) was measured as the sticking force, and the sticking resistance was examined. The N / 5 cm ² used here is a unit specified by the inventor in order to quantify the peel load with respect to the total contact area of the two sample pieces 40.

[Antimicrobial (antifungal)]
The sample 20 is punched into a rectangular flat plate shape (5 mm × 50 mm × 2 mm) to prepare sample pieces, and the antibacterial properties of each sample piece are based on the MIL modified method (MIL STD 810D Method 508.3 modified method). Examined. In this MIL modified method, first, 50 ml of co-test bacteria (62 bacteria (including 5 bacteria of JIS Z2911)) are added to and mixed with 500 ml of a liquid medium (SDA, PDA, M40Y). A solid (flat plate) medium was obtained by solidifying it in a petri dish having a shape in which a test piece can be placed inside. And each said test piece is mounted in the center part on the said solid culture medium, respectively, and it is left to stand (culture) for 30 days in the atmosphere of temperature 25 degreeC +/- 2 degreeC and relative humidity 95%, and then each test piece The antibacterial properties were examined by observing the surface of the plate (particularly, the side in contact with the medium).

  In addition, in the antibacterial item of Table 3 to be described later, the numeral “0” indicates a case where no bacterial growth was observed on the surface of the test piece (a level suitable as an antibacterial seal part), and the numeral “1” When the growth of the bacterium is slightly observed (level sufficient as an antibacterial seal part), the number “2” indicates the growth of the bacterium is slightly observed (a level that can be applied as an antibacterial seal part). The number “3” indicates that the growth of the fungus is slightly observed (a level that can be applied as an antibacterial seal part), and the number “4” indicates that the growth of the fungus is observed intensely. (Level of difficulty in application as antibacterial seal parts) shall be indicated.

[chemical resistance]
The sample 20 was punched into a rectangular flat plate shape (5 mm × 50 mm × 2 mm) to prepare sample pieces, and the chemical resistance of each sample was examined by conducting the test of five items shown in Table 2 below. In addition, in the chemical resistance item of Table 3 to be described later, the symbol “◎” satisfies all the evaluation criteria of each item of Table 2 and a state substantially equivalent to the initial state (before the chemical resistance test) is observed ( Parts that are exposed to a high-humidity atmosphere (hereinafter referred to as “parts suitable for high-humidity atmospheres”), the symbol “○” satisfies the evaluation criteria for each item in Table 2, and is substantially equivalent to the symbol “◎” The symbol “×” indicates that two or more of the items in Table 2 do not satisfy the evaluation criteria (applicable as a part under a high humidity atmosphere). Difficulty level).

  From the results shown in Table 3 above, the following were found.

<Rubber compounds P1 to P4, samples GP1 to GP4>
Rubber compounds P1 and P2 in which an alkaline inorganic filler (heavy coal cal 0.9 μm, talc 1.8 μm) having an arithmetic average particle size of less than 3 μm is blended, and acidic inorganic fillers (clay 1.5 μm, silica 4.0 μm) The rubber compounds P3 and P4 compounded with) had good kneadability and extrusion moldability, respectively. However, samples GP1 and GP2 of rubber moldings composed of the rubber compounds P1 and P2 have good antibacterial properties and the like, but have low lubricity and resistance to sticking, and samples GP3 of rubber moldings composed of the rubber compound P3. Has a low antibacterial property, and sample GP4 of the rubber molded body made of the rubber compound P4 has a low antibacterial property, lubricity and anti-sticking property.

  From this result, in the case of the compounds such as rubber compounds P1 to P4, the kneadability and extrusion moldability are good, but when the arithmetic average particle size of the alkaline inorganic filler is less than 3 μm, the rubber molded body It can be read that the contact area with the object to be contacted becomes large because the uneven surface is not formed. Moreover, when an acidic inorganic filler is blended instead of the alkaline inorganic filler, it can be read that sufficient antibacterial properties cannot be obtained unless a large amount of a photocatalyst inorganic filler, an antibacterial agent, or the like is blended. Furthermore, since the amount of bound rubber increases when an acidic inorganic filler is blended, it can be read that the lubricity and the like are reduced.

<Rubber compounds P5 to P9, samples GP5 to GP9>
Rubber compounds P5 to P7 in which the total blending amount of the alkaline inorganic filler is less than 40 phr, and rubber blends P8 and P9 in which the blending amount of heavy coal cal of 5.0 μm or talc of 5.0 μm of the alkaline inorganic filler is less than 20 phr are Both kneadability and extrusion moldability were low. In addition, rubber molded samples GP5 to GP8 made of the rubber compounds P5 to P8 had good antibacterial properties, but had low lubricity and anti-stick properties.

  From this result, in the blends such as rubber blends P5 to P9, even if an alkaline inorganic filler of 3 μm or more is blended, the blended amount (total blended amount, heavy coal cal 5.0 μm or talc 5 When the blending amount of .0 μm is too small, the composition of the composition is lowered, and the kneading processability and extrusion moldability of the composition are lowered (decrease in winding property on rolls, variation in discharge, etc.) ). In addition, it can be read that the uneven surface is not formed in the rubber molded body, and the contact area with the contact target is increased. Furthermore, it can be read that if a large amount of silicone compound or the like is not blended, the slipperiness and sticking resistance are not sufficient.

<Rubber compound P10 to P13 Sample GP10 to GP13>
Rubber compounds P10 and P11 in which the total amount of alkaline inorganic filler is more than 70 phr and rubber compound P12 in which a relatively large amount of antibacterial agent is compounded are low in kneading processability and extrusion moldability. The rubber compound P13 having a total compounding amount of 60 phr and containing no photocatalyst inorganic filler or antibacterial agent was excellent in kneadability and extrusion moldability.

  In samples GP10 and GP11 of rubber molded bodies composed of the rubber blends P10 and P11, the antibacterial property was good, but the slipperiness and sticking resistance were low. The rubber molded sample GP12 made of the rubber compound P12 had low chemical resistance in addition to lubricity and sticking resistance. Sample GP12 of a rubber molded body comprising the rubber compound P13 had good lubricity and anti-sticking property, but had low antibacterial properties.

  From this result, in the blends such as the rubber blends P10 to P13, even if an alkaline inorganic filler of 3 μm or more is blended, if the blending amount is excessive, the composition of the blend is reduced, It can be read that the kneading processability and extrusion moldability of the blend are lowered (decrease in winding property with respect to the roll, variation in discharge, etc.). Further, it can be read that the contact area with the contact target is increased because the uneven surface is not formed in the rubber molded body. Furthermore, it can be read that when a large amount of antibacterial agent is blended, the antibacterial property is improved, but the chemical resistance is lowered. Furthermore, it can be read that the antibacterial property cannot be obtained when the photocatalyst inorganic filler and the antibacterial agent are not included.

<Rubber compounds S1 to S9, samples GS1 to GS9>
40-70 phr alkaline inorganic filler with an arithmetic average particle size of 3.0 μm or more, and heavy calcium carbonate (heavy coal cal 5.0 μm, 3.0 μm), talc (talc 5.0 μm, 3.0 μm) Are blended with a photocatalyst inorganic filler, a rubber compound S1 containing no silicone compound and an antibacterial agent, and a rubber compound S2 to S9 containing a silicone compound but no antibacterial agent. The extrusion moldability was good. Further, the sample GS1 made of the rubber compound S1 has sufficient slipping properties, anti-sticking properties and antibacterial properties. Furthermore, samples GS2 to GS9 made of the rubber compounds S2 to S9 had better lubricity, resistance to sticking and antibacterial properties.

  From this result, like rubber compound S1-S9, the total compounding quantity of alkaline inorganic filler is 40-70 phr, and the compounding quantity of alkaline inorganic fillers other than talc and this talc (heavy calcium carbonate in a present Example) is It can be read that according to the blends in which the photocatalyst inorganic filler is blended at 20 phr or more, the blending property is sufficient and the blending processability and extrusion moldability of the blend are improved. In addition, it can be seen that the rubber molded body made of the compound has an uneven surface and a small contact area with the contact target. Furthermore, it can be read that sufficient slipping properties, anti-sticking properties, and antibacterial properties can be obtained even if a silicone compound, an antibacterial agent, or the like is not blended as in the document GS1 made of the rubber compound S1.

<Rubber compounds S10 to S14, Samples GS10 to GS14>
Heavy calcium carbonate (heavy coal cal 5.0 μm, 3.0 μm) and talc (talc 5.0 μm, 3.0 μm) are blended in a similar amount to the rubber compounds S1 to S9, and relatively few antibacterial agents Rubber compound S10, S11 containing rubber, rubber compound S12 containing antibacterial agent instead of photocatalyst inorganic filler, S13 containing thermal expansion capsule, rubber compound S14 having a relatively large amount of photocatalyst inorganic filler Each had good kneadability and extrusion moldability. Samples GS10 to GS12 made of the rubber blends S10 to S12 had sufficient lubricity, and good results were obtained in antibacterial properties. Furthermore, the samples GS13 and GS14 made of the rubber compounds S13 and S14 had better lubricity and resistance to sticking.

  From this result, according to the compound used to the extent that the properties of the target rubber material composition and the rubber molded product are not impaired in the antibacterial agent, the foaming agent, etc., as in the rubber compound S11 to S14, It can be read that the blending property and the kneading processability and extrusion moldability of the blend are improved. In addition, it can be seen that the rubber molded body made of the compound has an uneven surface and a small contact area with the contact target.

  In addition, in the case where the total blending amount of the alkaline inorganic filler is 40 to 70 phr as in the rubber blends S1 to S14, even if the blending amount of the alkaline inorganic filler other than talc and the talc is less than 20 phr (for example, If it is not too small as in the rubber compounds P8 and P9, the kneading processability and extrusion moldability are sufficient as in the rubber compounds S1 to S14, and the lubricity and resistance of the rubber molded body made of the rubber compound are sufficient. It was confirmed that the adhesiveness and antibacterial properties were sufficient.

  Although the present invention has been described in detail only for the specific examples described above, it is obvious to those skilled in the art that various changes and modifications are possible within the scope of the technical idea of the present invention. Such variations and modifications are naturally within the scope of the claims.

Explanatory drawing which shows the structural model of the rubber molded object formed by extrusion-molding and vulcanizing a rubber material composition. The schematic explanatory drawing of the sample (GS1-GS14, GP1-GP13) of the rubber molding used in the Example. Explanatory drawing which shows the measuring method of slipperiness in an Example. Explanatory drawing which shows the measuring method of sticking resistance in an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Rubber molding 10a ... Flat surface 10b ... Bleed thing 10c ... Uneven surface derived from alkaline inorganic filler 10d ... Removal area 20 ... Sample 30, 40 ... Sample piece

Claims (5)

Used for rubber moldings by extrusion vulcanization,
A rubber material composition comprising at least 100 phr of an ethylene-α-olefin / non-conjugated polyene copolymer, two or more kinds of alkaline inorganic fillers having an arithmetic average particle size of 3 μm or more, 40 phr to 70 phr, and an inorganic filler having a photocatalytic function A thing,
The said alkaline inorganic filler contains a talc at least, The rubber material composition characterized by the above-mentioned.   The rubber material composition according to claim 1, wherein a silicone compound is blended. Used for rubber moldings by extrusion vulcanization,
A rubber containing at least 100 phr of an ethylene-α-olefin / non-conjugated polyene copolymer, 40 phr to 70 phr of an alkaline inorganic filler having an arithmetic average particle size of 3 μm or more, 3 phr or less of an antibacterial agent, and a silicone compound A material composition comprising:
The said alkaline inorganic filler contains a talc at least, The rubber material composition characterized by the above-mentioned.   The rubber material composition according to any one of claims 1 to 3, wherein the alkaline inorganic filler includes talc (20 phr or more) and other alkaline inorganic fillers (20 phr or more). A rubber molded body obtained by extruding and vulcanizing the rubber material composition according to any one of claims 1 to 4,
A rubber molded body, wherein an uneven surface derived from an alkaline inorganic filler is formed on the surface side of the rubber molded body.

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