JPWO2021074959A1 - Manufacturing method of rubber packing with cloth, manufacturing method of leather packing, rubber packing with cloth, and leather packing - Google Patents

Abstract

The method for manufacturing the rubber packing containing cloth includes a first step (S100) and a second step (S200). In the first step (S100), at least one outer peripheral end portion (30A), (30B) of the tubular object (20) is wound inside (D8) or outside in the radial direction of the tubular object (20). A ring-shaped object (30) is formed. The tubular material (30) includes a cloth and a rubber composition. In the second step (S200), the ring-shaped object (40) is compression-molded.

Description

The present invention relates to a method for manufacturing a rubber packing containing a cloth, a method for manufacturing a leather packing, a rubber packing containing a cloth, and a leather packing.

Patent Document 1 discloses a rubber V-packing containing cloth. The rubber V-packing containing cloth disclosed in Patent Document 1 is formed by laminating rubber sheets containing cloth. Specifically, the rubber V-packing containing cloth disclosed in Patent Document 1 is obtained by executing the first to fifth steps in this order. In the first step, rubber glue is applied to the base cloth to form the first base cloth. In the second step, the base cloth is impregnated with lubricating oil to form the second base cloth. In the third step, the first base cloth and the second base cloth are alternately laminated to obtain a laminated body. In the fourth step, rubber glue is adhered to the outer peripheral surface of the laminated body to obtain an object to be molded. In the fifth step, the object to be molded is vulcanized into a V-shaped cross section.

Jikkenhei 4-132266

However, when the rubber packing containing cloth disclosed in Patent Document 1 is used for a long period of time, the lip surface may be peeled off and the first base cloth and the second base cloth may be delaminated. Therefore, the rubber V-packing containing cloth disclosed in Patent Document 1 may not have sufficient durability.

In view of the above problems, the present invention provides a method for manufacturing a rubber packing containing a cloth having excellent durability, a method for manufacturing a leather packing having excellent durability, a rubber packing containing cloth having excellent durability, and a leather packing having excellent durability. The purpose is.

The method for producing a rubber packing containing cloth of the present invention includes a first step and a second step. In the first step, at least one outer peripheral end of the tubular object is wound inside or outside in the radial direction of the tubular object to form a ring-shaped object. The tubular material contains a cloth and a rubber composition. In the second step, the ring-shaped object is compression-molded.

In certain embodiments, the first step includes a preparatory step, a cutting step, and a connecting step. In the preparation step, a rubber sheet is prepared. The rubber sheet contains the cloth and the rubber composition. In the cutting step, the rubber sheet is cut in the bias direction of the cloth to form a bias sheet. In the connecting step, both ends of the bias sheet are connected to form the tubular object.

In certain embodiments, the rubber composition comprises a nitrile rubber, a urethane rubber, a fluororubber, or a tetrafluorinated ethylene resin.

In certain embodiments, the rubber composition comprises a tetrafurinated ethylene resin.

In a certain embodiment, in the second step, the ring-shaped object is compression-molded into a V-ring shape.

The method for producing a leather packing of the present invention includes a first step, a second step, and a third step. In the first step, the first leather sheet is immersed in the first solution to form the second leather sheet. The first solution contains a sulfide-based synthetic rubber. In the second step, the second leather sheet is cut into a ring shape to form a ring shape. In the third step, the ring-shaped object is molded.

In a certain embodiment, in the first step, the first leather sheet is immersed in the first solution under a reduced pressure atmosphere. The decompressed atmosphere is lower than atmospheric pressure.

In certain embodiments, the first step comprises a pretreatment step. In the pretreatment step, the leather sheet is immersed in the pretreatment solution to form the first leather sheet. The pretreatment solution contains a vulcanization accelerator. The first solution contains an organic peroxide and a cyclic ether compound.

In a certain embodiment, in the first step, the first leather sheet is immersed in the first solution and then the first leather sheet is immersed in the second solution to form the second leather sheet. The second solution contains a lubricant.

The rubber packing containing cloth of the present invention has a leakage amount of 4.0 mL / 1000 times or less in a test based on the leakage test specified in JIS B 2403.

The leather packing of the present invention contains a polysulfide-based synthetic rubber.

According to the method for producing a rubber packing containing cloth of the present invention, a rubber packing containing cloth having excellent durability can be obtained. According to the method for producing a leather packing of the present invention, a leather packing having excellent durability can be obtained. According to the cloth-filled rubber packing and the leather packing of the present invention, the durability is excellent.

(A) is a perspective view of the cloth-filled rubber packing according to the first embodiment. (B) is a figure which shows the cross section of the rubber packing containing cloth cut by the cutting line IB shown in (a). It is sectional drawing of the hydraulic cylinder which shows the use state of the rubber packing containing cloth which concerns on Embodiment 1. FIG. It is a flowchart which shows the manufacturing process of the rubber packing containing cloth which concerns on Embodiment 1. (A) is a front view of the rubber sheet 10. (B) is a figure which shows the cross section of the rubber sheet cut by the cutting line IVB shown in (a). It is a schematic explanatory drawing for demonstrating the immersion process in Embodiment 1. FIG. (A) is a front view of the rubber sheet according to the first embodiment. (B) is a front view of the bias sheet according to the first embodiment. (A) shows a perspective view of the bias sheet according to the first embodiment. (B) shows a perspective view of a cylindrical object according to the first embodiment. (A) is a perspective view of a cylindrical object according to the first embodiment. (B) is a figure which shows the cross section of the cylindrical object cut by the cutting line VIIIB shown in (a). (A) is a perspective view of a ring-shaped object according to the first embodiment. (B) is a figure which shows the cross section of the ring-shaped object cut by the cutting line IXB shown in (a). (C) is a perspective view of a ring-shaped object to which a cover sheet is attached. (A) is a perspective view of the leather packing according to the second embodiment. (B) is a figure which shows the cross section of the leather packing cut by the cutting line IXB which shows (a). It is a flowchart of the manufacturing process of the leather packing which concerns on Embodiment 2. The vacuum apparatus 300 in Embodiment 2 is shown. (A) is a front view of the second leather seat according to the second embodiment. (B) is a perspective view of a ring-shaped object according to the second embodiment.

Hereinafter, a method for manufacturing a rubber packing with a cloth, a method for manufacturing a leather packing, a rubber packing with a cloth, and an embodiment of the leather packing according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals and the description is not repeated.

[Embodiment 1]
The cloth-filled rubber packing 1 according to the first embodiment will be described with reference to FIG. FIG. 1A is a perspective view of the cloth-filled rubber packing 1 according to the first embodiment. FIG. 1B is a diagram showing a cross section of the cloth-containing rubber packing 1 cut along the cutting line IB shown in FIG. 1A.

The cloth-containing rubber packing 1 according to the first embodiment is a cloth-containing rubber V packing. As shown in FIG. 1A, the cloth-containing rubber packing 1 is a torus-like material. The cloth-filled rubber packing 1 has a recess 1A. The recess 1A is formed over the entire circumference of the cloth-filled rubber packing 1. As shown in FIG. 1B, the cross-sectional shape of the cloth-filled rubber packing 1 is V-shaped. The cloth-filled rubber packing 1 has a groove 1B at the bottom of the recess 1A. The groove portion 1B is formed over the entire circumference of the cloth-filled rubber packing 1. A filler ring is attached to the groove 1B, if necessary.

The size of the rubber packing 1 containing cloth is not particularly limited. For example, the shape and dimensions of the cloth-containing rubber packing 1 may be any shape and dimensions specified in JIS B 2403: 2009.

The amount of leakage of the cloth-containing rubber packing 1 is 4.0 mL / 1000 times or less, preferably 1.0 mL / 1000 times or more and 2.0 mL / 1000 times or less, and more preferably 1.0 mL / 1000 times or more. 5 mL / 1000 times or less. Since the amount of leakage of the cloth-containing rubber packing 1 is 4.0 mL / 1000 times or less, the cloth-containing rubber packing 1 is excellent in long-term sealing of hydraulic oil. The amount of leakage of the rubber packing 1 containing cloth is a value measured by the method described in the examples of the present specification, and will be described in detail later.

The cloth-containing rubber packing 1 contains a cloth base material 11 and a vulcanized product 12S of a rubber composition. The vulcanized product 12S of the rubber composition covers the entire cloth base material 11. The vulcanized product 12S of the rubber composition indicates a rubber composition after vulcanization.

The cloth base material 11 functions as a reinforcing material for the cloth-containing rubber packing 1. The cloth base material 11 is composed of a single piece of cloth. In the first embodiment, the cloth base material 11 is a plain woven fabric. The material of the cloth base material 11 is not particularly limited, and includes, for example, organic fibers, inorganic fibers, or metal fibers. Organic fibers include, for example, cotton, rayon, aramid fibers, polyester fibers, or nylon fibers. Inorganic fibers include, for example, carbon fibers, ceramic fibers or glass fibers. Metallic fibers include, for example, stainless steel wire, Inconel wire, or Monel wire. These fibers may be used alone or in combination of two or more.

The rubber composition contains a rubber component. The rubber composition may contain a cross-linking aid, an activator, active zinc oxide, a vulcanizing agent, a vulcanization accelerator, a stabilizer, an anti-deterioration agent, a processing aid, or a plasticizer, if necessary. ..

The rubber component includes synthetic rubber. The type of synthetic rubber may be appropriately selected according to, for example, the type of hydraulic oil of the hydraulic cylinder 100 to which the rubber packing 1 containing cloth is mounted. Synthetic rubber includes nitrile rubber (NBR), urethane rubber (U), fluororubber (FKM), tetrafluoroethylene resin (PTFE), hydride nitrile rubber (HNBR), silicone rubber (Q), and ethylene propylene rubber (EPDM). ), Chloroprene rubber (CR), acrylic rubber (ACM), epichlorohydrin rubber (ECO) or butyl rubber (IIR). Among them, the rubber composition preferably contains nitrile rubber, urethane rubber, fluororubber, or ethylene tetrafluoride resin, and more preferably contains ethylene tetrafluoride resin. When the rubber component contains nitrile rubber, urethane rubber, fluororubber, or tetrafluoroethylene resin, the cloth-containing rubber packing 1 contains a mineral oil-based hydraulic oil, a W / O emulsion-based hydraulic oil, and an O / W emulsion-based hydraulic oil. Excellent resistance to. When the rubber component contains an ethylene tetrafluoride resin, the cloth-containing rubber packing 1 contains a mineral oil-based hydraulic oil, a W / O emulsion-based hydraulic oil, an O / W emulsion-based hydraulic oil, a water-glycol hydraulic oil, and a phosphoric acid. Excellent resistance to ester-based hydraulic oils and fatty acid ester-based hydraulic oils.

The cloth-containing rubber packing 1 is suitably used as, for example, a packing for a hydraulic device.

Next, a usage mode of the rubber packing 1 containing cloth will be described with reference to FIG. FIG. 2 is a cross-sectional view of a hydraulic cylinder 100 showing a usage state of the cloth-filled rubber packing 1 according to the first embodiment.

As shown in FIG. 2, the hydraulic cylinder 100 includes a cylinder 101, a piston rod 102, a male adapter 103, and a female adapter 104. The cloth-filled rubber packing 1 is used by being arranged between the cylinder 101 and the piston rod 102. Specifically, in the first embodiment, three rubber packings 1 containing cloth are stacked and used by being sandwiched between the male adapter 103 and the female adapter 104. As a result, the cloth-filled rubber packing 1 can suppress the leakage of hydraulic oil from the piston rod 102 of the hydraulic cylinder 100 for a long period of time.

Next, a method for manufacturing the rubber packing 1 containing cloth will be described with reference to FIG. FIG. 3 is a flowchart showing a manufacturing process of the cloth-containing rubber packing 1 according to the first embodiment.

As shown in FIG. 3, the method for manufacturing the cloth-containing rubber packing 1 according to the first embodiment includes a first step S100 and a second step S200. The first step S100 and the second step S200 are executed in this order. In the first step S100, the ring-shaped object 40 is formed. In the second step S200, the ring-shaped object 40 is compression-molded. In this way, the rubber packing 1 containing cloth is obtained.

Next, the first step S100 will be further described with reference to FIG. As shown in FIG. 3, the first step S100 includes a preparation step S110, a cutting step S120, a connecting step S130, and a winding step S140. The preparation step S110, the cutting step S120, the connecting step S130, and the winding step S140 are executed in this order.

In the preparation step S110, the rubber sheet 10 is prepared. In the cutting step S120, the bias sheet 20 is formed from the rubber sheet 10. In the connecting step S130, the tubular object 30 is formed from the bias sheet 20. In the winding step S140, the ring-shaped object 40 is formed from the tubular object 30.

Next, the preparation step S110 will be further described with reference to FIGS. 4 (a) and 4 (b). FIG. 4A is a front view of the rubber sheet 10 according to the first embodiment. FIG. 4B is a diagram showing a cross section of the rubber sheet 10 cut along the cutting line IVB shown in FIG. 4A.

In the preparation step S110, the rubber sheet 10 is prepared. As shown in FIG. 4A, the rubber sheet 10 is a rubber sheet containing a cloth. The rubber sheet 10 contains a cloth base material 11 and an unvulcanized product 12U of the rubber composition. As shown in FIG. 4B, the unvulcanized product 12U of the rubber composition fills the cloth base material 11 and covers the surface of the cloth 11. The unvulcanized product 12U of the rubber composition indicates a rubber composition before vulcanization.

The rubber sheet 10 is a sheet-like material. The dimensions of the rubber sheet 10 may be appropriately adjusted according to the dimensions of the bias sheet 20 and the like. The thickness of the rubber sheet 10 may be a foldable thickness. The thickness of the rubber sheet 10 is, for example, 1.00 mm or more and 1.07 mm or less.

The cloth base material 11 is a plain woven fabric. As shown in FIGS. 4 (a) and 4 (b), the plain woven fabric is a woven fabric in which weft threads 111 and warp threads 112 are alternately crossed vertically. The yarn density of the weft 111 and the yarn density of the warp 112 are substantially the same. The yarn density refers to the number of yarns per unit length. Hereinafter, the direction in which the weft 111 of the cloth base material 11 extends is described as "weft direction D1", and the direction in which the warp 112 of the cloth base material 11 extends is described as "warp direction D2".

As shown in FIG. 3, in the first embodiment, the preparation step S110 includes a kneading step S111 and a dipping step S112. The kneading step S111 and the dipping step S112 are executed in this order. In the kneading step S111, the materials of the rubber composition are kneaded to obtain a rubber composition. In the dipping step S112, the rubber sheet 10 is formed by using the cloth base material 11 and the rubber solution 120.

Next, the kneading step S111 will be further described. In the kneading step S111, the materials of the rubber composition are kneaded. As a result, a rubber composition is obtained. By kneading the materials of the rubber composition in this way, it becomes easy to obtain the rubber solution 120 in which the rubber composition is uniformly dispersed. The kneading step S111 can be performed using a kneading machine. Kneaders include rolls, banbury, or kneaders. Each of the mixing order of the materials of the rubber composition, the kneading time of the rubber composition, and the kneading temperature may be appropriately adjusted according to the material of the rubber composition, the type of the kneader, and the like.

Next, the immersion step S112 will be further described with reference to FIG. FIG. 5 is a schematic explanatory view for explaining the immersion step S112 in the first embodiment.

The dipping step S112 includes an adjusting step, a coating step, and a drying step. The adjusting step, the coating step, and the drying step are performed in this order. In the adjustment step, the rubber solution 120 is adjusted. In the coating step, the cloth base material 11 and the rubber solution 120 are used to form the coating sheet 10U. In the drying step, the rubber sheet 10 is formed from the covering sheet 10U.

Next, the adjustment step will be further described. In the preparation step, the kneaded rubber composition and the first solvent are put into a mixing device and mixed. As a result, a rubber solution 120 in which the rubber composition is dispersed is obtained. The obtained rubber solution 120 is put into the immersion tank 200, which will be described later with reference to FIG.

The first solvent includes, for example, methyl ethyl ketone (MEK), toluene, acetone, or methyl isobutyl ketone (MIBK). These may be used alone or in combination of two or more.

The blending amount of the rubber composition is, for example, 20 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the rubber solution 120.

Next, the immersion step will be further described with reference to FIG. As shown in FIG. 5, in the immersion step, the long cloth base material 11 is conveyed into the immersion tank 200 by a plurality of guide rolls 210. The elongated cloth base material 11 is wound around the feeding roll 220. As a result, the cloth base material 11 is immersed in the rubber solution 120 to obtain the coating sheet 10U. At this time, the transport direction D3 of the long cloth base material 11 and the weft direction D1 of the cloth base material 11 are substantially parallel to each other.

Next, the drying step will be further described with reference to FIG. In the drying step, the covering sheet 10U is conveyed into the heating furnace 230. The heating furnace 230 volatilizes the first solvent from the coating sheet 10U. As a result, the rubber sheet 10 is obtained. The drying conditions may be appropriately adjusted according to the material of the rubber composition and the like. The drying conditions include the temperature in the heating furnace 230 and the transport time in the heating furnace 230. The temperature in the heating furnace 230 is, for example, 98 ° C. or higher and 120 ° C. or lower. The transport time in the heating furnace 230 is, for example, 5 minutes or more and 7 minutes or less.

The rubber sheet 10 conveyed to the outside of the heating furnace 230 is taken up by the take-up roll 240. In this way, the rubber sheet 10 is continuously obtained.

Next, the cutting step S120 will be described with reference to FIGS. 6 (a) and 6 (b). FIG. 6A is a front view of the rubber sheet 10 according to the first embodiment. FIG. 6B is a front view of the bias sheet 20 according to the first embodiment.

As shown in FIG. 6A, in the cutting step S120, the rubber sheet 10 is cut in the bias direction C of the cloth base material 11. As a result, the bias sheet 20 shown in FIG. 6B is obtained.

The bias direction C of the cloth base material 11 indicates a direction oblique to the weft direction D1. The bias angle θ can be appropriately adjusted according to the relationship between the width of the rubber sheet 10 and the size of the rubber packing 1 containing cloth. The bias angle θ indicates an angle with respect to the weft direction D1. The bias angle θ is, for example, 45 ° C.

As shown in FIG. 6B, the shape of the bias sheet 20 is a substantially parallel quadrilateral shape. The bias sheet 20 has a first non-biased end 20A, a second non-biased end 20B, a first biased end 20C, and a second biased end 20D. The first bias end portion 20C and the second bias end portion 20D are formed by cutting the rubber sheet 10 in the bias direction C of the cloth base material 11. The longitudinal direction D4 of the first non-biased end 20A, the longitudinal direction D5 of the second non-biased end 20B, and the weft direction D1 are substantially parallel. The longitudinal direction D6 of the first bias end 20C and the longitudinal direction D7 of the second bias end 20D are substantially parallel. Each of the longitudinal direction D6 of the first bias end 20C and the longitudinal direction D7 of the second bias end 20D and the weft direction D1 are not substantially parallel. The dimensions of the bias sheet 20 are appropriately adjusted according to the dimensions of the rubber packing 1 containing cloth and the like.

Next, the connecting step S130 will be described with reference to FIGS. 7 (a) and 7 (b). FIG. 7A shows a perspective view of the bias sheet 20 according to the first embodiment. Specifically, FIG. 7A shows a bias sheet 20 in a state where both ends are butted against each other. FIG. 7B shows a perspective view of the tubular object 30 according to the first embodiment.

In the connecting step S130, both ends of the bias sheet 20 are connected to each other. Specifically, as shown in FIG. 7A, the first non-biased end 20A of the bias sheet 20 and the second non-biased end 20B are abutted against each other. Next, as shown in FIG. 7B, the first non-biased end 20A and the second non-biased end 20B of the bias sheet 20 are butt-sewn with the thread 31. As a result, the tubular object 30 is obtained.

In the first embodiment, both ends of the bias sheet 20 are connected by butt stitching, but the present invention is not limited to this. For example, both ends of the bias sheet 20 may be connected by a heat fusion method or an adhesive method. In the heat fusion method, both ends of the bias sheet 20 are heat-sealed. In the adhesive method, both ends of the bias sheet 20 are adhered to each other with an adhesive. Further, in the first embodiment, the first non-biased end 20A of the bias sheet 20 and the second non-biased end 20B are connected, but the present invention is not limited thereto. For example, the first bias end 20C and the second bias end 20D may be connected.

As shown in FIG. 7B, the cylindrical object 30 has a first outer peripheral end portion 30A, a second outer peripheral end portion 30B, and a connecting portion 30C. The first outer peripheral end portion 30A is formed by the first bias end portion 20C of the bias sheet 20. The second outer peripheral end portion 30B is formed by the second bias end portion 20D of the bias sheet 20. The connecting portion 30C is formed by a first non-biased end portion 20A of the bias sheet 20 and a second non-biased end portion 20B.

Next, the winding step S140 will be described with reference to FIGS. 8 and 9. FIG. 8A is a perspective view of the tubular object 30 according to the first embodiment. FIG. 8B is a diagram showing a cross section of the tubular object 30 cut along the cutting line VIIIB shown in FIG. 8A. FIG. 9A is a perspective view of the ring-shaped object 40 according to the first embodiment. FIG. 9B is a diagram showing a cross section of the ring-shaped object 40 cut along the cutting line IXB shown in FIG. 9A. FIG. 9C is a perspective view of the ring-shaped object 40 to which the cover sheet 41 is attached.

As shown in FIGS. 8A and 8B, in the winding step S140, the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the tubular object 30 are connected to the central axis O of the tubular object 30. Wrap inward in the radial direction with respect to. Specifically, the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the tubular object 30 are wound in the direction indicated by the arrow D8. As a result, the ring-shaped object 40 shown in FIGS. 9 (a) and 9 (b) is formed. Hereinafter, "inside the cylindrical object 30 in the radial direction with respect to the central axis O" will be described as "inside the tubular object 30".

In the first embodiment, as described with reference to FIG. 7B, the first non-biased end 20A and the second non-biased end 20B of the bias sheet 20 are connected to each other. Therefore, when the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the tubular object 30 are wound inside the tubular object 30, the crease direction of the tubular object 30 and the weft direction D1 or the warp thread direction D2 Are not approximately parallel. The crease direction of the tubular object 30 is substantially parallel to the circumferential direction R of the tubular object 30. The circumferential direction R of the tubular object 30 indicates the circumferential direction of the circle centered on the central axis O of the tubular object 30. As a result, even if the first outer peripheral end portion 30A or the second outer peripheral end portion 30B of the tubular object 30 is bent, the tubular object 30 is less likely to crack along the weft direction D1 or the warp direction D2. As a result, it becomes easy to obtain a rubber packing 1 containing a cloth having excellent durability. Further, the operator can easily form the ring-shaped object 40 from the tubular object 30.

In the first embodiment, the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the tubular object 30 are wound inside the tubular object 30, but the present invention is not limited to this. For example, one of the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the cylindrical object 30 may be wound inside the tubular object 30 or outside in the radial direction with respect to the central axis O of the cylindrical object 30. .. Hereinafter, "outside the radial direction of the cylindrical object 30 with respect to the central axis O" will be described as "outside the tubular object 30". Further, for example, after bending in two to the inside of the cylindrical object 30 or the outside of the cylindrical object 30, the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the cylindrical object 30 are formed of the tubular object 30. You may get caught inside. The number of times the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the tubular object 30 are involved is not particularly limited.

In the first embodiment, in the winding step S140, the cover sheet 41 is attached to the connecting portion 30C of the ring-shaped object 40. The cover sheet 41 covers the seam of the thread 31 at the connecting portion 30C of the ring-shaped object 40. As a result, a cloth-filled rubber packing 1 in which the thread 31 is not exposed on the surface can be obtained. That is, a rubber packing 1 containing a cloth having excellent design can be obtained. The cover sheet 41 may have the same configuration as the rubber sheet 10. The cover sheet 41 is obtained by cutting, for example, the rubber sheet 10.

Next, the second step S200 will be further described with reference to FIG. As shown in FIG. 3, in the first embodiment, the second step S200 includes a compression molding step S210 and a deburring step S220. The compression molding step S210 and the deburring step S220 are executed in this order.

In the compression molding step S210, a compression molding machine is used to obtain a compression molding from the ring-shaped product 40. The compression part may have burrs. In the deburring step S220, burrs are removed from the compression molded product.

In the first embodiment, in the compression molding step S210, the ring-shaped object 40 is compression-molded into a V-shaped ring. Specifically, the ring-shaped object 40 is placed directly in the cavity of the first mold, the first mold is closed, and molding is performed while applying pressure. As a result, the vulcanized product 12S is formed from the unvulcanized product 12U of the rubber composition of the ring-shaped product 40. The cavity of the first mold is formed in a V-ring shape.

The compression molding conditions may be appropriately adjusted according to the material of the rubber composition and the like. The compression molding conditions include vulcanization temperature and vulcanization time. The vulcanization temperature is, for example, 100 ° C. or higher and 200 ° C. or lower. The vulcanization time is, for example, 1 minute or more and 60 minutes or less.

As described with reference to FIGS. 1 to 9, the method for manufacturing the rubber packing containing cloth includes a first step S100 and a second step S200. In the first step S100, the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the tubular object 30 are wound inside the tubular object 30 to form the ring-shaped object 40. In the second step S200, the ring-shaped object 40 is compression-molded. As a result, the cloth-containing rubber packing 1 having higher durability than the cloth-containing rubber packing obtained by laminating the cloth-containing rubber sheets and compression molding can be obtained.

As described with reference to FIGS. 1 to 9, in the method for manufacturing the rubber packing containing cloth, the first step S100 includes a preparation step S110, a cutting step S120, and a connecting step S130. In the preparation step S110, the rubber sheet 10 is prepared. In the cutting step S120, the rubber sheet 10 is cut in the bias direction C of the cloth base material 11 to form the bias sheet 20. In the connecting step S130, both ends of the bias sheet 20 are connected to form a tubular object 30. As a result, when the tubular object 30 is formed into the ring-shaped object 40, the tubular object 30 is not easily cracked even if the first outer peripheral end portion 30A or the second outer peripheral end portion 30B of the tubular object 30 is bent. As a result, it is easy to obtain a cloth-containing rubber packing 1 having excellent long-term airtightness of hydraulic oil. Further, the operator can easily form the cylindrical object 30 into the ring-shaped object 40.

As described with reference to FIGS. 1 to 9, in the method for producing a rubber packing containing cloth, the rubber composition contains nitrile rubber, urethane rubber, fluororubber, or tetrafluorinated ethylene resin. As a result, a cloth-containing rubber packing 1 having excellent resistance to mineral oil-based hydraulic oil, W / O emulsion-based hydraulic oil, and O / W emulsion-based hydraulic oil can be obtained.

As described with reference to FIGS. 1 to 9, in the method for producing a rubber packing containing cloth, the rubber composition contains a tetrafluorinated ethylene resin. As a result, a cloth having excellent resistance to mineral oil-based hydraulic oil, W / O emulsion-based hydraulic oil, O / W emulsion-based hydraulic oil, water-glycol-based hydraulic oil, phosphoric acid ester-based hydraulic oil, and fatty acid ester-based hydraulic oil. The containing rubber packing 1 is obtained.

As described with reference to FIGS. 1 to 9, in the method for manufacturing the rubber packing containing cloth, in the second step S200, the ring-shaped object 40 is compression-molded into a V-ring shape. As a result, a rubber packing 1 containing a cloth that satisfies the test conditions specified in JIS B 2403 can be obtained. That is, a cloth-containing rubber packing 1 having excellent long-term airtightness of hydraulic oil can be obtained.

[Embodiment 2]
The leather packing 2 according to the second embodiment will be described with reference to FIGS. 10 (a) and 10 (b). FIG. 10A is a perspective view of the leather packing 2 according to the second embodiment. FIG. 10B is a diagram showing a cross section of the leather packing 2 cut along the cutting line XB shown in FIG. 10A.

As shown in FIGS. 10 (a) and 10 (b), the leather packing 2 according to the second embodiment is a leather V-packing. The shape and dimensions of the leather packing 2 may be the same as the shape and dimensions of the rubber packing 1 containing cloth except that the groove portion 1B is not provided.

The leather packing 2 is a compression molded product of leather. As a result, the leather packing 2 is flexible and highly elastic. Further, the wear coefficient of the leather packing 2 is low. That is, the leather packing 2 is excellent in slidability. Therefore, when the leather packing 2 is used, heat is less likely to be generated. As a result, the leather packing 2 is excellent in durability. Further, since the wear coefficient of the leather packing 2 is low, the leather packing 2 is less likely to damage the surface of the metal in contact with the leather packing 2.

Leather is formed by tanning the leather. Leather is less likely to rot and is easier to mold than leather. Leather is breathable. In other words, leather has a large number of micropores. The type of leather and the type of tanning may be appropriately selected according to the use of the leather packing 2. The skin includes cowhide, pig skin, goat skin, sheep skin, or horse leather. Tanning includes vegetable tannin tanning, chrome tanning, oil tanning, aluminum tanning, or combination tanning. Combination tanning includes the combination of two or more tanning agents. For example, combination tanning involves chrome tanning on the skin followed by further plant tannin tanning.

The leather packing 2 contains a polysulfide-based synthetic rubber. As a result, the leather packing 2 is more durable than the cloth-containing rubber packing obtained by laminating a cloth-containing rubber sheet and compression molding. Further, the leather packing 2 is flexible and retains elasticity even when exposed to a solvent. That is, the leather packing 2 has excellent solvent resistance. Solvents include thinner, MEK, or toluene.

The polysulfide-based synthetic rubber has a skeleton in which the main chain has the general formula-(RSx) n-. R is a hydrocarbon group. X is preferably an integer of 1 or more and 4 or less. n is preferably an integer of 1 or more and less than 30.

The product can be used as a polysulfide-based synthetic rubber. Thiokol (registered trademark) A, "Thiokol (registered trademark) AP", "Thiokol (registered trademark) B", "Thiokol (registered trademark) F", "Thiokol (registered trademark) FA" are the polysulfide-based synthetic rubbers. , "Thiokol® ST", "Thiokol LP®", "Thiokol® LP-2", "Thiokol® LP-282", "Thiokol® LP3" , "Thiokol® LP33", "Thiokol® N", or "Thiokol® R". These may be used alone or in combination of two or more. Above all, it is preferable to use "Thiokol (registered trademark) LP-2" as the polysulfide-based synthetic rubber. As a result, the leather packing 2 is superior in durability and solvent resistance.

In the second embodiment, the leather packing 2 further contains a lubricant. As a result, the leather packing 2 is superior in sealing property and slidability to the leather packing containing no lubricant.

Lubricants include microcrystalline wax, paraffin wax, white petrolatum, silicone oil, fluorooil, polyalkylene glycol, mineral oil, or liquid paraffin. These may be used alone or in combination of two or more.

The sealing medium of the leather packing 2 contains air, oil, solvent, alcohol, animal oil, synthetic agent, non-caustic aqueous solution, emulsion, hydrous fluid, fish oil, vacuum, petroleum base material, water, gasoline, or vegetable oil. Specifically, the leather packing 2 is suitably used as, for example, a packing for pneumatic equipment, a packing for hydraulic equipment, or a packing for hydraulic equipment.

Next, a method of manufacturing the leather packing 2 will be described with reference to FIG. FIG. 11 is a flowchart of the leather packing manufacturing process according to the second embodiment.

As shown in FIG. 11, the method for manufacturing the leather packing according to the second embodiment includes a first step S300, a second step S400, and a third step S500. The first step S300, the second step S400, and the third step S500 are executed in this order. In the first step S300, the second leather sheet 52 containing the polysulfide-based synthetic rubber is formed from the leather sheet 50. In the second step S400, the ring-shaped object 60 is formed from the second leather sheet 52. In the third step S500, the ring-shaped object 60 is compression-molded. In this way, the leather packing 2 is obtained.

Next, the first step S300 will be further described with reference to FIG. As shown in FIG. 11, the first step S300 includes a pretreatment step S310, a first dipping step S320, and a second dipping step S330. The pretreatment step S310, the first dipping step S320, and the second dipping step S330 are executed in this order.

In the pretreatment step S310, the pretreatment solution is immersed in the leather sheet 50 to form the first leather sheet 51 containing the vulcanization accelerator. In the first immersion step S320, the first solution 53 is immersed in the first leather sheet 51 to form the second leather sheet 52 containing the polysulfide-based synthetic rubber. In the second dipping step S330, the second solution is dipped in the second leather sheet 52, and the lubricant is incorporated into the second leather sheet 52.

Next, the pretreatment step S310 will be further described. In the pretreatment step S310, the pretreatment solution is immersed in the leather sheet 50. Next, the leather sheet 50 is taken out of the pretreatment solution and air-dried. By executing the pretreatment step S310, the first leather sheet 51 is obtained. As a result of executing the pretreatment step S310, the polysulfide-based synthetic rubber is easily taken into the inside of the first leather sheet 51 in the first dipping step S320.

The leather sheet 50 is a leather sheet-like material. The shape and dimensions of the leather sheet 50 may be appropriately adjusted according to the shape and dimensions of the leather packing 2.

The pretreatment solution contains a vulcanization accelerator and a second solvent.

The vulcanization accelerator includes, for example, a guanidine compound, a sulfenamide compound, a thiazole compound, a thiuram compound, a thiourea compound, a dithiocarbamic acid compound, an imidazoline compound, or a xanthate compound. Guanidine compounds include 1,3-diphenylguanidine, dioltotrilguanidine, or orthotrilbiguanidine. Sulfenamide compounds include N-cyclohexyl-2-benzothiazole sulfenamide or N-t-butyl-2-benzothiazolyl sulfenamide. Thiazole compounds include 2-mercaptobenzothiazole or di-2-benzothiazolyl disulfide. Thiram compounds include tetramethylthiuram disulfide or tetrabenzyl thiuram disulfide. These may be used alone or in combination of two or more. The content of the vulcanization accelerator is, for example, 3 parts by mass or more and 9 parts by mass or less with respect to 100 parts by mass of the pretreatment solution.

The second solvent includes, for example, MEK, toluene, acetone, or MIBK. These may be used alone or in combination of two or more.

The immersion time of the leather sheet 50 may be appropriately adjusted according to the dimensions of the leather sheet 50, the content of the vulcanization accelerator, and the like. The immersion time of the leather sheet 50 is, for example, 15 minutes or more and 20 minutes or less.

Next, the first immersion step S320 will be further described with reference to FIG. FIG. 12 is a diagram showing a vacuum device 300 according to the second embodiment. The first immersion step S320 will be described with reference to FIG.

In the first immersion step S320, the first leather sheet 51 is immersed in the first solution 53 under a reduced pressure atmosphere. Next, the first leather sheet 51 is taken out from the first solution 53 and air-dried. As a result, the second leather seat 52 is formed. By executing the pretreatment step S310, the polysulfide-based synthetic rubber is incorporated into the first leather sheet 51.

The first solution 53 contains a polysulfide-based synthetic rubber and a third solvent. In the second embodiment, the first solution 53 further contains an organic peroxide and a cyclic ether compound. As a result, the polysulfide-based synthetic rubber is easily crosslinked in the plurality of micropores of the first leather sheet 51. When the polysulfide-based synthetic rubber is crosslinked in the plurality of micropores of the first leather sheet 51, the polysulfide-based synthetic rubber is easily held inside the first leather sheet 51. As a result, a leather packing 2 incorporating a larger amount of polysulfide-based synthetic rubber can be obtained.

The third solvent contains MEK, toluene, acetone, or MIBK. These may be used alone or in combination of two or more.

The content of the polysulfide-based synthetic rubber is, for example, 50 parts by mass or more and 80 parts by mass or less with respect to 100 parts by mass of the first solution 53.

Organic peroxides include hydroperoxide compounds, dialkyl peroxide compounds, diacyl peroxide compounds, peroxyester compounds, ketone peroxide compounds, peroxyketal compounds, alkyl peroxide compounds, or peroxides. Contains carbonate compounds. Hydroperoxide compounds include cumene hydroperoxide. Dialkyl peroxide compounds include dicumyl peroxide. Diacyl peroxide compounds include benzoyl peroxide. Peroxy ester compounds include t-butyl peroxybenzoate. Ketone peroxide systems include methyl ethyl ketone peroxide. These may be used alone or in combination of two or more. The content of the organic peroxide is, for example, 0.1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the first solution 53.

Cyclic ether compounds include ethylene oxide, propylene oxide, butylene oxide, tetramethylene oxide, or tetrahydrofuran. These may be used alone or in combination of two or more. The content of the cyclic ether compound is, for example, 0.1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the first solution 53.

In the first immersion step S320, the vacuum device 300 can be used. By using the vacuum device 300, the polysulfide-based synthetic rubber is easily taken into the inside of the first leather sheet 51. Hereinafter, the first immersion step S320 using the vacuum device 300 will be described.

As shown in FIG. 12, the vacuum device 300 includes a vacuum tank 310, a vacuum pump 320, a pipe 330, and a valve 340. The vacuum tank 310 and the vacuum pump 320 are connected to each other via a pipe 330. The valve 340 is attached to the pipe 330. The vacuum tank 310 has a storage space S inside. The vacuum tank 310 has an opening / closing door 311 and a main body portion 312. The opening / closing door 311 is attached to the main body portion 312 so as to be openable / closable. When the opening / closing door 311 is open, the accommodation space S is open to the atmosphere. When the opening / closing door 311 is closed, the accommodation space S is sealed. The vacuum pump 320 sucks the air in the accommodation space S. The valve 340 opens or closes the flow path of the pipe 330. Specifically, when the valve 340 is open, the flow path of the pipe 330 is opened. When the valve 340 is closed, the flow path of the pipe 330 is closed.

First, the opening / closing door 311 is opened, and the first solution 53 and the first leather sheet 51 are put into the vacuum tank 310. Next, the opening / closing door 311 is closed. As a result, the gas space S1 and the liquid space S2 are formed in the accommodation space S. The liquid space S2 is formed by the first solution 53 and the first leather sheet 51. The gas space S1 indicates a space of the accommodation space S excluding the liquid space S2. The first leather sheet 51 is immersed in the first solution 53. At this time, the valve 340 is in the closed state.

Next, the valve 340 is opened. As a result, the gas space S1 is in a reduced pressure state. The first leather sheet 51 has a large number of micropores on its surface and inside. When the gas space S1 is depressurized, the air in the micropores tends to expand. This expanded air is easily separated from the first leather seat 51. As a result, the polysulfide-based synthetic rubber is easily incorporated into the first leather sheet 51.

The pressure of the gas space S1 in the depressurized state is lower than the atmospheric pressure. The pressure of the gas space S1 in the reduced pressure state is, for example, −0.09 MPa or more and −0.10 MPa or less. The holding time in the reduced pressure state may be appropriately adjusted according to the volume of the accommodation space S and the like. The holding time in the reduced pressure state is, for example, 5 minutes or more and 20 minutes or less.

At this time, it is preferable to perform alternate operations. The alternating operation means an operation in which the opening operation of the accommodation space S and the closing operation of the accommodation space S are alternately repeated at predetermined time intervals. The opening operation indicates an operation of closing the valve 340 and opening the opening / closing door 311. When the opening operation is performed, the pressure in the accommodation space S becomes substantially the same as the atmospheric pressure. The closing operation indicates an operation of closing the opening / closing door 311 and opening the valve 340. When the closing operation is performed, the pressure in the accommodation space S is reduced. By performing such an alternating operation, air can be more easily desorbed from the surface and the inside of the first leather sheet 51. As a result, the polysulfide-based synthetic rubber is easily taken in by the first leather sheet 51.

The operation interval and the number of repetitions when performing the alternate operation may be appropriately adjusted according to the volume of the accommodation space S and the like. For example, when the vacuum tank 310 has a small size (volume of the accommodation space S: about 20 L), the operation interval is preferably 2 minutes and the number of repetitions is 5. When the vacuum tank 310 has a large size (volume of the accommodation space S: about 35 L), the operation interval is preferably 3 minutes and the number of repetitions is 5.

Next, the valve 340 is closed, the opening / closing door 311 is opened, and the first leather seat 51 is taken out from the vacuum tank 310. Next, the first leather sheet 51 is air-dried. In this way, the second leather seat 52 is obtained.

In the second embodiment, the vacuum device 300 is used, but the present invention is not limited to this. In the present invention, for example, the first leather sheet 51 may be immersed in the first solution 53 under atmospheric pressure.

Next, the second dipping step S330 will be further described with reference to FIG. In the second dipping step S330, the second leather sheet 52 is dipped in the second solution. Next, the second leather sheet 52 is taken out from the second solution. In this way, the lubricant is incorporated into the second leather seat 52.

The second solution contains a lubricant. In the second embodiment, the second solution is a melting solution of the lubricant. The temperature of the second solution may be appropriately adjusted according to the type of lubricant. The temperature of the second solution is, for example, 35 ° C. or higher and lower than 100 ° C.

The lubricant preferably contains white petrolatum. White petrolatum is solid at room temperature. Therefore, the leather packing 2 that further suppresses the penetration of the sealing medium can be obtained.

The immersion time of the second leather sheet 52 may be appropriately adjusted according to the dimensions of the second leather sheet 52 and the like. The immersion time of the second leather sheet 52 is, for example, 1 minute or more and 10 minutes or less.

The second leather sheet 52 taken out from the second solution may be air-dried. When the lubricant contains white petrolatum, when the second leather sheet 52 is taken out from the second solution, the white petrolatum solidifies at room temperature.

Next, the second step S400 will be further described with reference to FIGS. 11 and 13 (a) and 13 (b). FIG. 13A is a front view of the second leather seat 52 according to the second embodiment. FIG. 13B is a perspective view of the ring-shaped object 60 according to the second embodiment.

As shown in FIG. 11, the second step S400 includes a cutting step S410. As shown in FIG. 13A, in the cutting step S410, the second leather sheet 52 is cut into a ring shape. Specifically, the second leather sheet 52 is cut along the ring-shaped cutting line CL. As a result, the ring-shaped object 60 shown in FIG. 13 (b) is obtained. The dimensions of the ring-shaped object 60 may be appropriately adjusted according to the dimensions of the leather packing 2.

Next, the third step S500 will be further described with reference to FIG. In the second embodiment, as shown in FIG. 11, the third step S500 includes a preforming step S510 and a main molding step S520. The preforming step S510 and the main forming step S520 are executed in this order. Since the third step S500 includes the preforming step S510 and the main molding step S520, it becomes easy to mold the ring-shaped object 60 into a desired size.

In the pre-molding step S510, the ring-shaped product 60 is molded into the pre-molded product by using a compression molding machine.

In the main molding step S520, the premolded product is molded into the leather packing 2 by using a compression molding machine. In the preforming step S510, the ring-shaped object 60 is placed directly in the cavity of the second mold, the second mold is closed, and molding is performed while pressurizing. As a result, a preformed product is obtained. The cavity of the second mold is formed in a substantially V-ring shape.

The temperature of the second mold is, for example, 100 ° C. or higher and 150 ° C. or lower. The molding time may be appropriately adjusted according to the size of the ring-shaped object 60 and the like. The molding time is, for example, 2 minutes or more and 4 minutes or less. The pressure is, for example, 18.6 MPa or more and 19.6 MPa or less.

In the main molding step S520, the premolded product is placed directly in the cavity of the third mold, the third mold is closed, and molding is performed while applying pressure. The cavity of the third mold is formed in a V-ring shape.

The temperature of the third mold is, for example, 100 ° C. or higher and 150 ° C. or lower. The molding time may be appropriately adjusted according to the size of the ring-shaped object 60 and the like. The molding time is, for example, 4 minutes or more and 10 minutes or less. The pressure is, for example, 18.6 MPa or more and 19.6 MPa or less.

In the main molding step S520, when the compression molding is completed, the third mold may be cooled while the compression molded product is still in the third mold. The third mold has a cooling flow path inside. By circulating the cooling water through the cooling flow path of the third mold, the temperature of the third mold is lowered. As a result, the temperature of the third mold can be cooled to room temperature.

In the second embodiment, the third step S500 includes the preforming step S510 and the main molding step S520, but the present invention is not limited thereto. The third step S500 does not have to include the preforming step S510.

As described with reference to FIGS. 10 to 13, the method for manufacturing the leather packing includes a first step S300, a second step S400, and a third step S500. In the first step S300, the first leather sheet 51 is immersed in the first solution 53 to form the second leather sheet 52. In the second step S400, the second leather sheet 52 is cut into a ring shape to form a ring-shaped object 60. In the third step S500, the ring-shaped object 60 is formed. As a result, a leather packing having excellent durability and solvent resistance can be obtained.

As described with reference to FIGS. 10 to 13, in the first step S300, the first leather sheet 51 is immersed in the first solution 53 under a reduced pressure atmosphere lower than the atmospheric pressure. The first leather seat 51 has a large number of micropores. Under a reduced pressure atmosphere, air escapes from the large number of micropores in the first leather sheet 51, and the sulfide-based synthetic rubber is easily taken into the first leather sheet 51. As a result, a leather packing 2 incorporating a larger amount of polysulfide-based synthetic rubber can be obtained. That is, a leather packing 2 having more excellent solvent resistance can be obtained.

As described with reference to FIGS. 10 to 13, in the first step S300, the leather sheet 50 is immersed in the pretreatment solution to form the first leather sheet 51. The first solution 53 contains an organic peroxide and a cyclic ether compound. As a result, a leather packing 2 incorporating a larger amount of polysulfide-based synthetic rubber can be obtained. That is, a leather packing 2 having further excellent solvent resistance can be obtained.

As described with reference to FIGS. 10 to 13, in the first step S300, the first leather sheet 51 is immersed in the first solution 53, and then the first leather sheet 51 is immersed in the second solution. The second leather sheet 52 is formed. The first leather seat 51 has a large number of micropores. Lubricant is easily taken into a large number of micropores. As a result, a leather packing 2 having more excellent sealing property and slidability can be obtained.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention is not limited to the examples.

[Example 1: Rubber packing with cloth 1]
The following materials were used as the material of the rubber packing 1 containing the cloth.

<Rubber component>
-Product name "Nipol (registered trademark) 1042" (NBR, manufactured by Zeon Corporation)
<Vulcanizing agent>
-Product name "SULFAX (registered trademark) 200SS" (sulfur, manufactured by Tsurumi Chemical Industry Co., Ltd.)
<Vulcanization accelerator>
-Product name "Noxeller CZ-G" (N-cyclohexyl-2-benzothiazolyl sulfeneamide, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.)
-Product name "Noxeller TT-P" (Tetramethylthiuram disulfide, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.)
<Cloth base material>
-Product name "22C 115 width" (manufactured by Shinko Orifu Co., Ltd., thickness: 0.9 mm, weave: plain weave)

(Preparation step S110: Kneading step S111)
The rubber component, the vulcanizing agent, and the vulcanization accelerator were put into a roll machine at the ratios shown in Table 1 and kneaded. As a result, a rubber composition was obtained. The kneading temperature was about 90 ° C.

(Preparation step S110: Immersion step S112)
The kneaded rubber composition and the first solvent were put into a mixing device and mixed. As a result, a rubber solution 120 was obtained. The obtained rubber solution 120 was put into the immersion tank 200. The content of the rubber composition was 26.4 parts by mass with respect to 100 parts by mass of the rubber solution 120. As the first solvent, a mixed solvent of toluene and MEK was used. The mass ratio of toluene and MEK (mass of toluene / mass of MEK) was 1.5 (60/40).

The long cloth base material 11 was conveyed into the immersion tank 200 by a plurality of guide rolls 210. As a result, a covering sheet 10U was obtained. The transport direction D3 of the long cloth base material 11 and the weft direction D1 of the cloth base material 11 were substantially parallel.

Next, the covering sheet 10U was conveyed into the heating furnace 230. The temperature in the heating furnace 230 was, for example, about 98 ° C. The transport time in the heating furnace 230 was about 7 minutes.

In this way, the rubber sheet 10 was continuously obtained.

(Cut step S120)
As shown in FIG. 6A, the rubber sheet 10 was cut in the bias direction C of the cloth base material 11. As a result, the bias sheet 20 shown in FIG. 6B was obtained.

(Connecting step S130)
As shown in FIG. 7A, the first non-bias end 20A of one bias sheet 20 and the second non-bias end 20B were butted against each other. Next, as shown in FIG. 7B, the first non-biased end 20A and the second non-biased end 20B of the bias sheet 20 were butt-sewn with a thread 31. As a result, the tubular object 30 was obtained.

(Enrollment step S140)
As shown in FIGS. 8 (a) and 8 (b), the first outer peripheral end portion 30A and the second outer peripheral end portion 30B of the tubular object 30 were wound inside the tubular object 30. As a result, the ring-shaped object 40 shown in FIGS. 9 (a) and 9 (b) was formed. Next, as shown in FIG. 9C, the cover sheet 41 was attached to the connecting portion 30C of the ring-shaped object 40. The cover sheet 41 was obtained by cutting the rubber sheet 10.

(Compression molding step S210)
The ring-shaped object 40 was compression-molded into a V-shaped ring. As a result, a compression molded product was obtained. The vulcanization temperature was 160 ° C. The vulcanization time was 10 minutes.

(Deburring step S220)
The burrs on the compression part were removed. As a result, the rubber packing 1 containing cloth was obtained.

[Leakage test]
The amount of leakage of the rubber packing 1 containing cloth was measured by a method conforming to the leakage test specified in JIS B 2403. As a result, the amount of leakage of the cloth-containing rubber packing 1 was 1.5 mL / 1000 times or less. As a result, it was confirmed that the rubber packing 1 containing the cloth was excellent in long-term airtightness of the hydraulic oil.

[Example 2: Leather packing 2]
The following materials were prepared as materials for the leather packing 2.

<First leather seat 51>
-Product name "Combination leather" (manufactured by SPIRE Leather, leather: cowhide, tanning: combination tanning)
<Vulcanization accelerator>
-Product name "Noxeller DP" (1,3-diphenylguanidine, manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.)
<Second solvent>
-Product name "MEK" (Methyl ethyl ketone, manufactured by Daishin Chemical Co., Ltd.)
<Polysulfide synthetic rubber>
-Product name "Thiokol (registered trademark) LP-2" (manufactured by Toray Fine Chemicals Co., Ltd.)
<Organic peroxide>
-Product name "Park Mill (registered trademark) H-80" (cumene hydroperoxide, manufactured by NOF CORPORATION)
<Cyclic ether compound>
・ Product name "Special grade propylene oxide" (1,2-epoxypropane, manufactured by Kishida Chemical Co., Ltd.)
<Third solvent>
・ Product name "Toluene" (Toluene, manufactured by Chuo Kasei Seihin Co., Ltd.)
-Product name "MEK" (Methyl ethyl ketone, manufactured by Daishin Chemical Co., Ltd.)
<Wax>
-Product name "Microcrystalline Wax" (microcrystalline wax)
<Vaseline>
・ Product name "White Petrolatum" (white petrolatum, manufactured by Ishii Kiyoshi Shoten Co., Ltd.)

(Pretreatment step S310)
The vulcanization accelerator and the second solvent were mixed to obtain a pretreatment solution. The content of the vulcanization accelerator was, for example, 6 parts by mass with respect to 100 parts by mass of the pretreatment solution.

Then, the leather sheet 50 was immersed in the pretreatment solution. The immersion time of the leather sheet 50 was 15 minutes. The leather sheet 50 was taken out from the pretreatment solution and dried at room temperature for about 1 week. As a result, the first leather seat 51 was obtained.

(First Immersion Step S320)
The polysulfide-based synthetic rubber and the third solvent were mixed to obtain a first solution 53. Next, an organic peroxide and a cyclic ether compound were added to the obtained first solution 53 and mixed to prepare a first solution 53. The content of the polysulfide-based synthetic rubber was 66 parts by mass with respect to 100 parts by mass of the first solution 53. The content of the organic peroxide was 2.0 parts by mass with respect to 100 parts by mass of the first solution 53. The content of the cyclic ether compound was 1.7 parts by mass. As the first solvent, a mixed solvent of toluene and MEK was used. The mass ratio of toluene and MEK (mass of toluene / mass of MEK) was 1.0 (50/50).

The opening / closing door 311 was opened, and the first solution 53 and the first leather sheet 51 were put into the vacuum tank 310 (volume of the accommodation space S: about 35 L). Next, the opening / closing door 311 was closed and alternate operations were performed. The operation interval of the alternating operation was 3 minutes, and the number of repetitions of the alternating operation was 5. At this time, the cumulative time of the decompressed state in the accommodation space S was 15 minutes. The pressure of the gas space S1 in the reduced pressure state was −0.10 MPa.

Next, the valve 340 was closed, the opening / closing door 311 was opened, and the first leather seat 51 was taken out from the vacuum tank 310. Next, the first leather sheet 51 was dried at room temperature for about one week.

(Second Immersion Step S330)
The wax and petrolatum were heated to 90 ° C. to obtain a second solution. The wax content was 13 parts by mass with respect to 100 parts by mass of the second solution.

Next, the first leather sheet 51 was immersed in the second solution. The immersion time of the first leather sheet 51 was 3 minutes. The first leather sheet 51 was taken out from the second solution to obtain a second leather sheet 52.

(Cut step S410)
As shown in FIG. 13A, the second leather seat 52 was cut into a ring shape. As a result, a ring-shaped object 60 was obtained.

(Preliminary molding step S510)
The ring-shaped object 60 was placed directly in the cavity of the second mold, the second mold was closed, and molding was performed while applying pressure. As a result, a preformed product was obtained. The temperature of the second mold was 125 ° C. The molding time was 3 minutes. The molding pressure was 19.6 MPa.

(Main molding step S520)
The premolded product was placed directly in the third mold cavity, the second mold was closed, and molding was performed while pressurizing. The temperature of the third mold was 125 ° C. The molding time was 6 minutes. The molding pressure was 19.6 MPa.

Next, 6 minutes after the start of compression molding of the premolded product, cooling water was circulated in the cooling flow path of the third mold while the compression molded product was still in the third mold, and the third mold was formed. The mold was cooled to room temperature. As a result, the leather packing 2 was obtained.

The embodiments of the present invention have been described above with reference to the drawings (FIGS. 1 to 13). However, the present invention is not limited to the above-described embodiment, and can be implemented in various aspects without departing from the gist of the present invention (for example, (1) to (11) shown below). The drawings are schematically shown mainly for each component for easy understanding, and the thickness, length, number, etc. of each component shown are different from the actual ones for the convenience of drawing creation. .. Further, the material, shape, dimensions, etc. of each component shown in the above embodiment are merely examples, and are not particularly limited, and various changes can be made without substantially deviating from the effects of the present invention. be.

(1) As described with reference to FIGS. 1 to 9, the shape of the cloth-filled rubber packing 1 according to the first embodiment is a V-ring, but the present invention is not limited thereto. For example, the shape of the cloth-containing rubber packing 1 may be J packing, L packing, U packing, W packing, Y packing, D ring, O ring, T ring, X ring, or square ring. Each of J packing, L packing, U packing, W packing, Y packing, D ring, O ring, T ring, X ring, and square ring is specified in JIS B 0116: 2015.

(2) As described with reference to FIGS. 1 to 9, the cloth base material 11 according to the first embodiment is a plain woven fabric, but the present invention is not limited thereto. For example, the cloth base material 11 may be a twill fabric, a knitted fabric, or a non-woven fabric.

(3) As described with reference to FIGS. 1 to 9, in the method for manufacturing the cloth-containing rubber packing according to the first embodiment, the first step S100 includes the preparation step S110, the cutting step S120, the connecting step S130, and the first step S100. The present invention includes, but is not limited to, the winding step S140. For example, the first step S100 may not include the preparation step S110, the cutting step S120, and the connecting step S130.

(4) As described with reference to FIGS. 1 to 9, in the method for manufacturing a rubber packing containing cloth according to the first embodiment, the preparation step S110 includes a kneading step S111 and a dipping step S112. Not limited to this. The preparation step S110 may not include the kneading step S111 and the dipping step S112. In this case, the rubber sheet 10 may be a product of another company.

(5) As described with reference to FIGS. 10 to 13, the shape of the leather packing 2 according to the second embodiment is a V-ring, but the present invention is not limited thereto. For example, the shape of the leather packing of the present invention may be a ring type, a bowl type, a hat type, or a groove type.

(6) As described with reference to FIGS. 10 to 13, in the method for manufacturing the leather packing according to the second embodiment, the first step S300 includes the pretreatment step S310, the first dipping step S320, and the second dipping. The present invention includes, but is not limited to, step S330. For example, the first step S300 may not include the pretreatment step S310 and the second dipping step S330.

The present invention is useful in the fields of, for example, a method for manufacturing a rubber packing containing a cloth, a method for manufacturing a leather packing, a rubber packing containing a cloth, and a leather packing.

1 Cloth-filled rubber packing 1A Recess 1B Groove 10 Rubber sheet 10U Coating sheet 11 Cloth base material 111 Weft 112 Warp 12S Vulcanized rubber composition 12U Unvulcanized rubber composition 20 Bias sheet 20A 1st non-biased end 20B 2nd non-biased end 20C 1st bias end 20D 2nd bias end 30 Cylindrical object 30A 1st outer peripheral end 30B 2nd outer peripheral end 30C Connecting part 31 Thread 40 Ring-shaped 41 Cover sheet 52 2nd leather Sheet 53 First solution 60 Ring

Claims (11)

The first step of forming a ring-shaped object by winding at least one outer peripheral end of the tubular object containing the cloth and the rubber composition inside or outside the tubular object in the radial direction.
A method for manufacturing a rubber packing containing a cloth, which comprises a second step of compression molding the ring-shaped material. The first step is
A preparatory step for preparing a rubber sheet containing the cloth and the rubber composition, and
A cutting step of cutting the rubber sheet in the bias direction of the cloth to form a bias sheet, and
The method for manufacturing a rubber packing containing a cloth according to claim 1, further comprising a connecting step of connecting both ends of the bias sheet to form the tubular object. The method for producing a rubber packing containing a cloth according to claim 1 or 2, wherein the rubber composition contains nitrile rubber, urethane rubber, fluororubber, or tetrafluorinated ethylene resin. The method for producing a rubber packing containing a cloth according to any one of claims 1 to 3, wherein the rubber composition contains a tetrafluorinated ethylene resin. The method for producing a rubber packing containing cloth according to any one of claims 1 to 4, wherein in the second step, the ring-shaped object is compression-molded into a V-ring shape. The first step of immersing the first leather sheet in the first solution containing the sulfide-based synthetic rubber to form the second leather sheet, and
The second step of cutting the second leather sheet into a ring shape to form a ring shape, and
The third step of forming the ring-shaped object and
Manufacturing method of leather packing including. The method for producing a leather packing according to claim 6, wherein in the first step, the first leather sheet is immersed in the first solution under a reduced pressure atmosphere lower than atmospheric pressure. The first step includes a pretreatment step of immersing the leather sheet in a pretreatment solution containing a vulcanization accelerator to form the first leather sheet.
The method for producing a leather packing according to claim 6 or 7, wherein the first solution contains an organic peroxide and a cyclic ether compound. In the first step, after immersing the first leather sheet in the first solution, the first leather sheet is immersed in a second solution containing a lubricant to form the second leather sheet. The method for manufacturing a leather packing according to claim 7 or 8. A rubber packing containing cloth having a leakage amount of 4.0 mL / 1000 times or less in a test based on the leakage test specified in JIS B 2403. Leather packing containing polysulfide synthetic rubber.

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