WO2015147246A1

WO2015147246A1 - Surface treatment solution for rubber article, method of surface modification of rubber article, and method for producing rubber article

Info

Publication number: WO2015147246A1
Application number: PCT/JP2015/059566
Authority: WO
Inventors: 雄石井; 奥田　智昭
Original assignee: 三菱電線工業株式会社
Priority date: 2014-03-27
Filing date: 2015-03-27
Publication date: 2015-10-01
Also published as: JP6002864B1; TW201542648A; JP6495244B2; JPWO2015147246A1; JP2016180122A

Abstract

Provided is a surface treatment solution for a rubber article, the solution being composed of a solution obtained by dissolving a dichloroisocyanuric acid salt in an aqueous solvent. Also provided is a method for producing a rubber-made article, the method including a surface treatment step for using a treatment solution composed of a solution obtained by dissolving a dichloroisocyanuric acid salt in an aqueous solvent to perform a surface treatment on a vulcanized rubber molding, after a rubber molding manufacturing step for manufacturing the vulcanized rubber molding from a rubber composition.

Description

Surface treatment liquid for rubber products, surface modification method for rubber products, and method for producing rubber products

The present invention relates to a surface treatment solution for rubber products, a surface modification method for rubber products, and a method for producing rubber products.

Generally, a rubber product is obtained by kneading a rubber composition in which various additives such as a crosslinking agent are blended with a rubber material (raw rubber) as a base component, and kneaded the rubber composition (rubber composition after the kneading process). Is molded into a desired shape such as a sheet or tube (preliminary molding process), and the resulting unvulcanized rubber molded body is further vulcanized (vulcanized molding process). Unnecessary parts are removed from the body to finish the molded body (finishing process), and thereafter, washing, drying, etc. are performed, and the final product is obtained through an inspection process, a packaging process, and the like.

If a rubber molded product that has undergone a vulcanization molding process tends to adhere during the manufacturing process of such a rubber product, the handleability of the rubber molded product (product) in the subsequent inspection process and packaging process of the rubber molded product (product) will be reduced. Therefore, it is preferable that the rubber molded body (that is, the vulcanized rubber molded body) that has undergone the vulcanization molding process is less likely to adhere (that is, has adhesion resistance). For example, Patent Document 1 discloses that 10 to 30% by weight of a low molecular weight polyethylene glycol and, if necessary, a microcristan wax as an anti-sticking agent capable of preventing sticking (adhesion) of vulcanized rubber with respect to the total amount thereof. An anti-adhesive agent emulsified in an oil-in-water type with 20 to 40% by weight of a nonionic surfactant and 80 to 120% by weight of a long-chain fatty acid salt has been proposed. However, this anti-blocking agent needs to be used at a high concentration in order to exert a sufficient anti-adhesion effect. Therefore, if the anti-blocking agent is added to vulcanized rubber, There is a problem of deteriorating physical properties.

On the other hand, it is conventionally known that surface treatment of rubber or resin is performed using a halide of isocyanuric acid such as trichloroisocyanuric acid or dichloroisocyanuric acid. For example, Patent Documents 2 and 3 disclose that isocyanuric acid halides reduce the friction coefficient of the rubber surface and improve ozone resistance. Patent Document 3 discloses that a treatment liquid in which trichloroisocyanuric acid is dissolved in water is advantageous in that wrinkles generated in rubber can be prevented as compared with a treatment liquid in which trichloroisocyanuric acid is dissolved in an organic solvent. It has been broken.

Sliding parts of pneumatic cylinders, solenoid valves, spool valves, etc. used to open and close doors in trains, that is, members that rotate or reciprocate (pistons, spools, etc.) and members that face them (cylinders, sleeves) Etc.) in order to seal the fluid flowing between them without impairing the slidability, a seal such as packing is attached. In a so-called sliding portion seal applied to such a sliding portion, it is necessary to seal the working liquid or working gas that operates the moving portion without impairing the sliding property of the moving portion. Therefore, it is required that the surface friction coefficient is small. As this type of seal, for example, nitrile rubber (NBR) is often used from the viewpoint of cost, oil resistance, etc., but nitrile rubber has a high coefficient of friction. For this reason, when the surface of the seal made of nitrile rubber is treated with a treatment liquid disclosed in the above prior art documents (Patent Documents 2 and 3) in which trichloroisocyanuric acid is dissolved in ethyl acetate, the treatment liquid is obtained. As a result, it was found that when the seal was stretched, cracks occurred on the surface of the seal and the sealing performance deteriorated. In addition, when an organic solvent is used as a solvent, the concentration of the treatment liquid is easily changed because the organic solvent is easily volatilized, and there is a disadvantage that the load on the environment is large. Therefore, a treatment liquid in which trichloroisocyanuric acid is dissolved in water is used. Although it examined, in the process liquid which dissolved the trichloroisocyanuric acid in water, since the trichloroisocyanuric acid cannot be dissolved in high concentration, it turned out that the friction coefficient reduction effect by a process is not enough. On the other hand, seals made of rubber, the main component of which are industrially mass-produced, are stored in a lump until they are actually installed on the device or equipment. It is necessary to work to separate the stickers that have adhered and adhered to each other before being attached to an apparatus or device. For this reason, it is the cause of reducing the manufacturing efficiency of the apparatus and apparatus in which the seal is mounted.

JP-A-60-203649 JP-A-56-63432 JP 60-108438 A

The present invention has been made in view of the above circumstances, and the problem to be solved is to impart low friction to the surface of rubber products (particularly rubber seals) without reducing extensibility. Another object of the present invention is to provide a surface treatment solution for rubber products and a method for modifying the surface of rubber products using the surface treatment solution, which can also provide an adhesion preventing effect between rubber products during storage.

In addition, when producing a rubber product comprising a vulcanized rubber molded body from a rubber composition, it is possible to prevent adhesion between the rubber molded bodies without causing deterioration in physical properties of the rubber molded body. An object of the present invention is to provide a method for producing a rubber product that can efficiently produce the product.

In addition, when producing a rubber product composed of a vulcanized rubber molded body from a rubber composition, it is possible to prevent adhesion between the rubber molded bodies without lowering the physical properties of the rubber molded body. An object of the present invention is to provide a method for producing a rubber product, which can efficiently produce a rubber product imparted with friction.

As a result of diligent research to solve the above problems, the inventors of the present invention can dissolve dichloroisocyanurate in an aqueous solvent at a high concentration, and the solution is contained in rubber products (particularly rubber seals). It has been found that it is difficult to penetrate into the surface of the rubber product and can impart low friction and adhesion to the surface of rubber products (especially rubber seals).

In addition, a solution obtained by dissolving dichloroisocyanurate in an aqueous solvent does not easily penetrate into a rubber molded body (vulcanized rubber molded body) in the production process of a rubber product, and the rubber molded body surface-treated with the solution. The physical properties of the rubber are hardly changed with respect to the physical properties of the rubber molded body (vulcanized rubber molded body) before being surface-treated with the solution. It has been found that if the molded body) is surface-treated, the rubber molded body can be provided with excellent adhesion and low friction.

In addition, a solution in which dichloroisocyanurate is dissolved in an aqueous solvent is not necessarily heated and attached to the surface of the rubber molded body. It was found that the surface treatment reaction can proceed.

The present invention has been completed based on such findings, and the features thereof are as follows.
[1] A surface treatment solution for rubber products, comprising a solution in which dichloroisocyanurate is dissolved in an aqueous solvent.
[2] The surface treatment liquid according to the above [1], wherein the dichloroisocyanurate is an alkali metal dichloroisocyanurate.
[3] The surface treatment liquid according to the above [1], wherein the dichloroisocyanurate is sodium dichloroisocyanurate.
[4] The surface treatment solution according to any one of [1] to [3] above, wherein the concentration of dichloroisocyanurate in the solution is 2 to 20% by weight.
[5] The surface treatment liquid according to any one of the above [1] to [4], which is a solution heated to 50 to 70 ° C.
[6] The surface treatment liquid according to any one of [1] to [5] above, wherein the rubber product is a rubber seal.
[7] The surface treatment liquid according to [6] above, wherein the rubber seal contains nitrile rubber (NBR).
[8] The surface treatment liquid according to the above [6], wherein the rubber seal is a sliding portion rubber seal.
[9] A method for modifying the surface of a rubber product, comprising applying the surface treatment liquid according to any one of [1] to [5] to the surface of the rubber product.
[10] The method according to [9] above, wherein the surface treatment liquid is heated to 50 to 70 ° C. and applied to the surface of the rubber product.
[11] The method according to [9] or [10] above, comprising immersing a rubber product in the surface treatment liquid.
[12] The method according to [11] above, wherein the immersion time is 1 to 30 minutes.
[13] The method according to any one of [9] to [12] above, wherein the rubber product is a rubber seal.
[14] After the rubber molded body manufacturing step for manufacturing a vulcanized rubber molded body from the rubber composition, the vulcanized rubber molded body is treated with a treatment liquid at 20 to 70 ° C. comprising a solution in which dichloroisocyanurate is dissolved in an aqueous solvent. A method for producing a rubber product, comprising a surface treatment step (I) for performing surface treatment of a body.
[15] After the rubber molded body manufacturing process, a finishing process for removing unnecessary portions from the vulcanized rubber molded body obtained through the rubber molded body manufacturing process, and an inspection for inspecting the appearance of the vulcanized rubber molded body after the finishing process Including a process, or in addition to the finishing process and the inspection process, further including a packaging process of packaging the vulcanized rubber molded body that has undergone the inspection process,
[14] The surface treatment step (I) is performed in (i) a period after the rubber molded body preparation step and before the finishing step, and / or (ii) after the finishing step and before the inspection step. ] The manufacturing method of the rubber product of description.
[16] In the case of further having a cleaning process and a drying process before the inspection process, and having a surface treatment process (I) after the finishing process and before the inspection process, the cleaning process is performed after the surface treatment process (I). And the method according to [15] above, wherein a drying step is performed.
[17] The method according to any one of [14] to [16] above, wherein the surface treatment step (I) of applying the treatment liquid to the surface of the rubber molded body is a step of immersing the rubber molded body in the treatment liquid. .
[18] The method according to [17] above, wherein the immersion time is 10 seconds to 30 minutes.
[19] Instead of the surface treatment step (I),
A first step of applying a treatment liquid of 40 ° C. or less comprising a solution of dichloroisocyanurate in an aqueous solvent to the surface of the vulcanized rubber molded body, and heating and washing of the treatment liquid adhered to the surface of the vulcanized rubber molded body The method for producing a rubber product according to [14] above, further comprising a surface treatment step (II) including a second step of performing the step.
[20] The method according to [19] above, wherein the first step is a step of immersing the vulcanized rubber molded article in a treatment liquid having a temperature of 40 ° C. or lower.
[21] The method described in [20] above, wherein the immersion time is 1 second to 10 minutes.
[22] The method according to any one of [19] to [21] above, wherein the heating temperature of the treatment liquid in the second step is higher than 40 ° C and lower than 100 ° C.
[23] The above-mentioned [19], wherein the second step is a step of immersing the vulcanized rubber molded body having the treatment liquid attached to the surface through the first step in warm water having a temperature of more than 40 ° C and not more than 100 ° C. ] To [21].
[24] The method described in [23] above, wherein the immersion time is 1 to 10 minutes.
[25] After the rubber molded body manufacturing process, a finishing process for removing unnecessary portions from the vulcanized rubber molded body obtained through the rubber molded body manufacturing process and an inspection for inspecting the appearance of the vulcanized rubber molded body after the finishing process Including a process, or in addition to the finishing process and the inspection process, further including a packaging process of packaging the vulcanized rubber molded body that has undergone the inspection process,
[19] The surface treatment step (II) is carried out in (i) after the rubber molded body preparation step and before the finishing step and / or (ii) after the finishing step and before the inspection step [19 ] To [22] The method according to any one of [22].
[26] After the rubber molded body manufacturing process, a finishing process for removing unnecessary portions from the vulcanized rubber molded body obtained through the rubber molded body manufacturing process, and an inspection for inspecting the appearance of the vulcanized rubber molded body after the finishing process Including a process, or in addition to the finishing process and the inspection process, further including a packaging process of packaging the vulcanized rubber molded body that has undergone the inspection process,
[23] The surface treatment step (II) is performed in (i) a period after the rubber molded body preparation step and before the finishing step, and / or (ii) after the finishing step and before the inspection step [23 ] Or the method according to [24].
[27] Before the inspection step, further having a cleaning step and a drying step, and after the finishing step and before the inspection step, and having the surface treatment step (II), the temperature of the cleaning step exceeds 40 ° C. The method according to [26] above, wherein the vulcanized rubber molded article is immersed in warm water of 100 ° C. or lower and applied to the second step of the surface treatment step (II).
[28] The rubber composition comprises nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), [14] to [27], wherein an additive is blended with one or more rubbers selected from the group consisting of butyl rubber (IIR), natural rubber (NR), and ethylene-propylene-diene rubber (EPDM). ] The method as described in any one of.
[29] The method according to any one of the above [14] to [27], wherein the rubber composition is a niryl rubber composition in which an additive is blended with niryl rubber.
[30] The method according to any one of [14] to [29] above, wherein the rubber product is a rubber seal.

The surface treatment liquid for rubber products of the present invention can effectively impart low friction and adhesion properties to rubber products such as rubber seals without reducing the extensibility of the rubber products. In particular, even a rubber product including a rubber having a high surface friction coefficient such as nitrile rubber (NBR) can be imparted with low friction without reducing the extensibility of the rubber product. For this reason, for example, by applying a surface treatment to a rubber seal containing nitrile rubber (NBR) with the treatment liquid, the slidability of the moving part is improved while utilizing the excellent oil resistance and mechanical properties of nitrile rubber (NBR). A seal for the sliding portion that can be maintained can be realized. In addition, since rubber products treated with the surface treatment liquid for rubber products of the present invention exhibit excellent adhesion, adhesion between the rubber products during storage can be prevented, and the devices and equipment to which the rubber products are mounted can be prevented. Since it is not necessary to separate the rubber products adhering to each other at the manufacturing site, the manufacturing efficiency of the apparatus and equipment is improved.

Moreover, since the surface treatment liquid for rubber products of the present invention is a solution composed of an aqueous solvent, it can be used after being heated to room temperature or higher, and is heated and applied to the surface of the rubber product. The processing effect can be further enhanced.

Further, according to the method for producing a rubber product of the present invention (an embodiment having the surface treatment step (I) or an embodiment having the surface treatment step (II)), a rubber product comprising a vulcanized rubber molded body is produced from the rubber composition. In doing so, it is possible to prevent adhesion between the rubber molded bodies without deteriorating the working environment, and it is possible to efficiently produce a rubber product having the desired physical properties (physical characteristics). Further, in addition to preventing adhesion between rubber molded bodies, it is possible to impart low friction to the rubber molded bodies. For example, from a nitrile rubber composition containing a nitrile rubber having a high coefficient of friction against metal to a metal. On the other hand, it is possible to obtain a rubber product (vulcanized rubber molding) exhibiting low friction.

In addition, according to the rubber product manufacturing method of the present invention (an embodiment having the surface treatment step (I) or an embodiment having the surface treatment step (II)), the rubber product is susceptible to precipitation (bloom, bleed, etc.). In the case where the rubber molded body containing the dichloroisocyanurate is dissolved in an aqueous solvent, the rubber molded body (vulcanized rubber molded body) in which no precipitation occurs immediately after the vulcanization molding step is produced. The surface treatment prevents the subsequent precipitation, that is, the precipitation (bloom, bleed, etc.) from the rubber product during the finishing process, inspection process and packaging process, and during storage and transportation after the packaging process. And a more reliable rubber product can be manufactured.

In addition, according to the rubber product manufacturing method of the present invention (a mode having the surface treatment step (II)), since the treatment liquid near room temperature is used, deterioration of the treatment liquid can be suppressed, and the surface treatment is repeatedly performed. It is only necessary to replenish the treatment liquid, and there is no problem of discarding the deteriorated treatment liquid. For this reason, costs associated with the processing liquid can be reduced, and there is no concern about environmental pollution because the processing liquid is not discarded.

In addition, “normal temperature” in this specification means 20 ° C. ± 15 ° C. (5-35 ° C.) defined in JIS Z 8703, and “near normal temperature” means 1-40 ° C.

Hereinafter, the present invention will be described with reference to preferred embodiments thereof.

[Surface treatment liquid and surface modification method]
The surface treatment liquid for rubber products of the present invention (hereinafter simply referred to as “surface treatment liquid” or “treatment liquid”) consists of a solution in which dichloroisocyanurate is dissolved in an aqueous solvent. A typical example of the rubber product to be treated includes a rubber seal (particularly, a rubber seal for a sliding portion).

In the present invention, the “aqueous solvent” is typically water, but an aqueous solution in which a water-soluble organic solvent is dissolved in water can also be used as the “aqueous solvent”. Examples of such water-soluble organic solvents include lower alcohols such as methanol and ethanol; lower ketones such as acetone and methyl ethyl ketone; lower carboxylic acids such as acetic acid; glycols such as ethylene glycol, propylene glycol and diethylene glycol; acetaldehyde And aldehydes. The water-soluble organic solvent is used within a range that does not significantly reduce the solubility of dichloroisocyanurate in water, and can usually be used within a range of 30% by weight or less based on water.

In the present invention, the “dichloroisocyanurate” can be used without particular limitation as long as it is a salt that can be dissolved in an aqueous solvent. However, from the viewpoint of the effect of imparting low friction, alkali such as sodium salt and potassium salt can be used. Metal salts are preferred and sodium salts are particularly preferred. In addition, the sodium dichloroisocyanurate and potassium dichloroisocyanurate can also use the hydrate which has crystal water other than a normal anhydride. In the present invention, one or more dichloroisocyanurates can be used.

The content of dichloroisocyanurate in the surface treatment liquid of the present invention (that is, a solution in which dichloroisocyanurate is dissolved in an aqueous solvent) is preferably 2 to 20% by weight, more preferably 2 to 15%, based on the entire treatment liquid. % By weight, particularly preferably 2 to 10% by weight, most preferably 5 to 10% by weight. When the amount is more than 20% by weight, the amount of bubbles generated during the surface treatment of the rubber product with the treatment liquid increases, the reaction due to the surface treatment is inhibited, and the desired effect is hardly obtained. If it is less than 2% by weight, it tends to be difficult to impart sufficient low friction to the surface of the rubber product.

The method for modifying the surface of a rubber product of the present invention is performed by applying (contacting) the surface treatment liquid of the present invention to the surface of the rubber product. Since the surface treatment liquid of the present invention is a solution composed of an aqueous solvent, it can be stored at room temperature, and the solvent hardly evaporates even when heated to room temperature or higher. Further, the rubber product is heated in a state where the surface treatment liquid of the present invention is heated to about 50 to 70 ° C. and maintained at a temperature of 50 to 70 ° C., that is, in a state where the surface treatment liquid of the present invention is heated to 50 to 70 ° C. A higher treatment effect (surface modification effect) can be obtained by attaching to the surface. When the surface treatment liquid is heated to a temperature exceeding 70 ° C., the amount of bubbles generated during the surface treatment of the rubber product increases, and the treatment effect tends to decrease. The treatment liquid may permeate and make uniform treatment difficult. Further, the evaporation of the aqueous solution becomes remarkable, which is not preferable from the viewpoint of the life of the treatment liquid.

The method of applying (contacting) the surface treatment liquid of the present invention to the surface of the rubber product is not particularly limited, but the treatment of immersing the rubber product in the treatment liquid, the treatment of spraying the treatment liquid onto the rubber product, brushing, etc. However, the dipping treatment is preferable from the viewpoint that the operation is simple and the effect can be obtained in a short time. The immersion time is preferably about 1 to 15 minutes, more preferably about 1 to 10 minutes. If it exceeds 15 minutes, fine cracks (cracks confirmed by observation with a scanning electron microscope (SEM) at 1000 times) are generated on the surface of the rubber product, and the performance of the rubber product tends to be lowered. If it is less than 1 minute, it will become difficult to obtain a sufficiently high low-friction imparting effect and / or a sufficiently high adhesion-preventing effect. After the surface treatment liquid of the present invention is applied to the rubber seal surface, the treatment liquid on the rubber seal surface is usually washed by immersing the rubber seal in water or an organic solvent such as alcohol for several seconds, and then taken out and naturally dried at room temperature. When the temperature of the treatment liquid and the cleaning liquid is high, the rubber seal is taken out at a high temperature, which leads to shortening of the drying time during drying. Therefore, the above-described treatment liquid heated to 50 to 70 ° C. is preferable from the viewpoint of the treatment efficiency of surface modification. *

[Production method of rubber products]
The method for producing a rubber product of the present invention (hereinafter also abbreviated as “the method of the present invention”) is a method in which a dichloroisocyanurate is dissolved in an aqueous solvent after a rubber molded body preparation step for preparing a vulcanized rubber molded body from a rubber composition. The main feature is that it has a surface treatment step of attaching the treatment liquid comprising the solution to the surface of the rubber molded body.

Similar to conventional rubber product manufacturing methods, the rubber molded body preparation step for preparing a vulcanized rubber molded body from the rubber composition in the method of the present invention involves pre-molding the kneaded rubber composition and further vulcanizing the rubber composition. A mode of molding (that is, a mode comprising a preforming step of preforming a kneaded rubber composition and a vulcanization molding step of vulcanizing a rubber molded body obtained through the preforming step), or The kneaded rubber composition is injection molded to obtain a vulcanized rubber molded body.

In addition, after the rubber molded body manufacturing process, basically, the appearance inspection of the vulcanized rubber molded body that has undergone the finishing process and finishing process to remove unnecessary portions of the vulcanized rubber molded body obtained in the rubber molded body manufacturing process is performed. Includes inspection process. In addition, the vulcanized rubber molded product that has undergone the finishing process is washed and dried in order to remove rubber scraps generated in the finishing process, to improve the appearance of the rubber product, to stabilize the surface properties, etc. After performing the drying process), the inspection process may be performed. In many cases, the vulcanized rubber molded product (rubber product) that has been made a good product through the inspection process is stored and distributed after shipment. In order to protect the product in the process, the packaging material may be counted (that is, after a predetermined number is counted) and then packaged (that is, having a packaging process).

In the present specification, “vulcanization” in “unvulcanized”, “vulcanized molding”, “vulcanized rubber” and the like refers to the polymer molecule of rubber using sulfur or sulfur and a vulcanization accelerator. Not only does it chemically combine to make it three-dimensional, but it means not only the three-dimensional state, but also uses a cross-linking agent other than sulfur, such as an organic peroxide, to chemically modify the rubber polymer molecules. To be three-dimensionally combined with or the three-dimensional state.

Hereinafter, the rubber composition and each step in the method of the present invention will be described in detail.
The rubber composition includes various rubber materials such as a crosslinking agent, a crosslinking accelerator, a scorch inhibitor, an anti-aging agent, a filler, a plasticizer, a crosslinking aid, a processing aid, a process oil, and a flame retardant. These additives are added to a kneader together with the rubber material.

The rubber material is not particularly limited. For example, nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber ( CR), butyl rubber (IIR), natural rubber (NR), ethylene-propylene-diene rubber (EPDM) and the like. One or more rubber materials can be used.

The cross-linking agent is a material added to chemically bond rubber polymer molecules into a three-dimensional structure, and sulfur or organic peroxide is preferably used. Examples of the organic peroxide include di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, 1,1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3,1,3-di (t -Butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate, t-butylperoxyisopropyl carbonate, n-butyl-4,4-di Examples thereof include (t-butylperoxy) valerate. One or more crosslinking agents can be used.

Examples of the crosslinking accelerator include thiuram vulcanization accelerators, sulfenamide vulcanization accelerators, thiazole vulcanization accelerators, dithiocarbamate vulcanization accelerators, and the like. Examples of the scorch inhibitor include N-cyclohexylthiophthalimide, N-nitrodiphenylamine, phthalic anhydride, N-phenyl-N- (trichloromethylthio) benzenesulfonamide, and the like. Examples of the anti-aging agent include amine-based anti-aging agents, phenol-based anti-aging agents, and imidazole-based anti-aging agents. Examples of the filler include carbon black, calcium carbonate, silica, barium sulfate, titanium oxide, magnesium hydroxide, aluminum hydroxide, talc, clay, graphite, calcium silicate, and the like. Examples of the plasticizer include phthalic acid plasticizers such as dioctyl phthalate (DOP), adipic acid plasticizers such as dioctyl adipate, sebacic acid plasticizers such as dioctyl sebacate, and tri- (2-ethylhexyl) trimellitate. Examples thereof include trimellitic acid plasticizers such as polyethers, and polymerization plasticizers such as polyethers and polyesters. Examples of the crosslinking aid include triallyl cyanurate, triallyl isocyanurate, N, N′-m-phenylenebismaleimide, trimethylolpropane trimethacrylate, triallyl trimellitate, 1,2-polybutadiene and the like. Multifunctional compounds are exemplified. Examples of processing aids include stearic acid, palmitic acid, paraffin wax, and the like. Examples of the process oil include aromatic process oil, naphthene process oil, paraffin process oil, and the like. Examples of the flame retardant include hydrated metal oxides such as aluminum hydroxide and magnesium hydroxide, and bromine compounds such as decabromodiphenylethane. Each additive other than these crosslinking agents can be used alone or in combination of two or more as in the case of the crosslinking agent.

The blending amount of various additives in the rubber composition is appropriately adjusted according to a conventional method according to the use, required characteristics, etc. of the rubber product to be manufactured. For example, when manufacturing a sealing material using nitrile rubber as a rubber material, the following composition is illustrated as a typical composition of a rubber composition.

(Composition Example 1)
Nitrile rubber: 100 parts by weight Crosslinking agent (typically sulfur): 0.1 to 3 parts by weight Filler (typically carbon black): 20 to 150 parts by weight Crosslinking accelerator: 2 to 6.5 parts by weight Processing aid: 0.1-5 parts by weight Plasticizer: 3-20 parts by weight Anti-aging agent: 0.5-5 parts by weight Zinc oxide: 3-7 parts by weight

Further, when a sealing material is produced using EPDM as a rubber material, the following composition is exemplified as a typical composition of the rubber composition.

(Composition example 2)
EPDM: 100 parts by weight Zinc oxide: 3-7 parts by weight Stearic acid: 0.3-1.5 parts by weight Carbon black: 50-120 parts by weight Naphthenic oil: 30-80 parts by weight Vulcanization accelerator: 0.7 -2.4 parts by weight Sulfur: 0.1-3 parts by weight

The kneading of the rubber composition is performed using a known kneader (for example, an open roll, an intermix, a kneader, a Banbury mixer, etc.), a twin-screw kneading extruder, or the like. The kneading temperature, kneading conditions, and the like are appropriately set according to conventional methods according to the use, required characteristics, etc. of the rubber product to be manufactured.

In the pre-molding step, the kneaded rubber composition is pre-molded into a shape close to a rubber product (vulcanized rubber molded body) to be manufactured or a shape that is easy to mold. For the pre-molding, devices such as an extruder, an open roll, and a pre-former that are widely used in a pre-molding process in manufacturing a conventional rubber product are preferably used. The shape and size of the unvulcanized rubber molded body obtained by preforming are appropriately selected in consideration of the shape and size of the rubber product (vulcanized rubber molded body) to be manufactured. In addition, when obtaining a vulcanized rubber molded body by injection molding, a preforming process is unnecessary by finishing in a ribbon shape at the time of kneading in advance. After the kneading process, the vulcanization molding is performed without passing through the preforming process. A process is performed.

In the vulcanization molding step, for example, by using an injection molding machine, a compression molding machine, a hot press molding machine, or the like, heat molding is performed at a predetermined temperature to obtain a vulcanized rubber molded body. The heating temperature and the heating time are appropriately set according to the rubber material, the shape of the rubber product to be manufactured, and the like, but are generally selected within the range of 130 to 200 ° C. and 1 to 120 minutes. Specifically, for example, when the rubber composition is a nitrile rubber composition, suitable temperature conditions include a mode of heating at about 150 to 200 ° C. for about 2 to 30 minutes.

The vulcanized rubber molded body obtained through the vulcanization molding process usually has unnecessary parts such as burrs, and therefore, a finishing process for removing unnecessary parts such as burrs is performed. The finishing process is usually performed by an apparatus or a human hand using a punching machine, a hand-knot, or the like.

In the cleaning process performed after the finishing process, tap water or industrial ion exchange water is usually sprayed or poured on the surface of the rubber molded body as a cleaning liquid, or tap water or industrial ion exchange water is used. The rubber molded body is dipped in a cleaning tank filled with. By the washing process, the vulcanized rubber molded body that has undergone the finishing process is transferred to a packing operation. From the viewpoint of suppressing the adhesion of impurities to the rubber molded body surface, it is preferable to use ion-exchanged water as the cleaning liquid. As the ion-exchanged water, for example, the conductivity at 25 ° C. is 5 to 25 MΩ. · Cm, preferably 10 to 20 MΩ · cm is preferably used. The temperature of the cleaning solution may be normal temperature or higher than normal temperature, and considering the subsequent drying step, it is preferably higher in the range of 20 to 80 ° C. than normal temperature. Also, two or more, preferably three or more (eight or less) cleaning tanks may be provided, and the cleaning effect is improved by transferring the rubber molding in a plurality of cleaning tanks.

The drying step is a step of drying the rubber molded body that has undergone the cleaning process, and usually the rubber molded body is naturally dried in the air. In order to accelerate drying, for example, drying may be performed by blowing hot air of about 50 to 100 ° C.

The inspection step is a step of inspecting the appearance of the rubber molded body by visual inspection, a magnifying glass, an image analysis device or the like to inspect the surface of the rubber molded body for a final rubber product. In this inspection process, good products and defective products are selected.

The packaging process is a process in which a rubber molded body that has undergone the inspection process is packaged with a packaging material in order to store the rubber product or protect the rubber product during the transportation process after shipment. In such a packaging process, a plurality of rubber moldings are randomly packed in a packaging bag. Here, “packaging” means “industrial packaging” for the purpose of transportation.

In the method of the present invention, as described above, after the rubber molded body preparation step for preparing a vulcanized rubber molded body from the rubber composition, a treatment liquid (hereinafter referred to as “the present invention”) comprising a solution in which dichloroisocyanurate is dissolved in an aqueous solvent. A surface treatment step of performing a surface treatment of the vulcanized rubber molded body using a "treatment liquid") is performed. Here, the “treatment liquid comprising a solution in which dichloroisocyanurate is dissolved in an aqueous solvent” is the same as the aforementioned surface treatment liquid for rubber products. Such a treatment liquid hardly penetrates into the inside of the rubber molded body, acts only on the surface of the rubber molded body, and gives adhesion to the surface of the rubber molded body without deteriorating the physical properties of the rubber molded body. To do.

The content of dichloroisocyanurate in the treatment liquid is preferably 2 to 20% by weight, more preferably 2 to 15% by weight, and particularly preferably 2 to 10% by weight based on the whole treatment liquid. When the amount is more than 20% by weight, the amount of bubbles generated during the surface treatment of the rubber molded body with the treatment liquid increases, the reaction by the surface treatment is inhibited, and the desired effect is hardly obtained. If it is less than 2% by weight, it tends to be difficult to impart sufficient low friction to the surface of the rubber molded body.

The method of the present invention includes the method according to the first aspect in which the surface treatment step comprises a step (surface treatment step (I)) of subjecting the vulcanized rubber molded body to a surface treatment with a treatment liquid at 20 to 70 ° C. The process includes a first process in which a treatment liquid of 40 ° C. or less is applied to the surface of the vulcanized rubber molded body, and a second process in which the treatment liquid adhered to the surface of the vulcanized rubber molded body is heated and washed ( The method of the 2nd aspect which consists of surface treatment process (II)) is included.

The first aspect surface treatment step (I) is performed in (i) a period after the rubber molded body preparation step and before the finishing step, and / or (ii) after the finishing step and before the inspection step. . In addition, when surface treatment process (I) is implemented in the period before (ii) finishing process and before an inspection process, a washing process and a drying process are usually after surface treatment process (I) and before an inspection process. Done. In the surface treatment step (I), as described later, after the treatment liquid is applied to the surface of the rubber molded body, it is usually washed and dried with water or alcohol, but the surface treatment step ( Cleaning and drying in I) can be omitted.

A higher treatment effect is achieved by heating the treatment liquid to 20 to 70 ° C. and applying it to the surface of the rubber molded body in a state where the temperature of 20 to 70 ° C. is maintained (the treatment liquid is heated to 20 to 70 ° C.). (Adhesiveness imparting effect) can be obtained. When the treatment liquid is heated to a temperature exceeding 70 ° C., the amount of bubbles generated during the surface treatment of the rubber molded body increases, and the treatment effect decreases. Further, the treatment liquid partially penetrates into the rubber molded body, and uniform treatment tends to be difficult. When the treatment liquid is at a temperature lower than 20 ° C., the surface treatment does not proceed and the production efficiency is lowered. A treatment liquid heated in a range of 50 ° C. or higher and 70 ° C. or lower is particularly preferable.

The method of attaching (contacting) the treatment liquid to the surface of the rubber molded body is not particularly limited, but the method of immersing the rubber molded body in the treatment liquid, the method of spray-coating the treatment liquid on the rubber molded body, the rubber molded body Examples include a method of brushing the treatment liquid, a method of pouring the treatment liquid over the rubber molded body, etc., but the work is simple, an effect can be obtained in a short time, and a large number of rubber molded bodies can be collected at once. The immersion treatment is preferable from the viewpoint that the treatment can be performed uniformly.

The immersion time is preferably about 10 seconds to 30 minutes, more preferably about 30 seconds to 15 minutes. When it exceeds 30 minutes, the influence of the penetration of the treatment liquid into the product occurs, and the surface tends to crack by tension. If it is less than 10 seconds, it tends to be difficult to obtain a sufficiently high adhesion-imparting effect. After the treatment liquid has been applied to the surface of the rubber molded body, the rubber molded body surface is usually washed by immersing the rubber molded body in water or an organic solvent such as alcohol for several seconds, and then removed and air-dried at room temperature. Let

The second aspect surface treatment step (II) is performed in (i) a period after the rubber molded body production step and before the finishing step, and / or (ii) after the finishing step and before the inspection step. . When the surface treatment process (II) is performed in the period after the finishing process (ii) and before the inspection process, the cleaning process and the drying process are usually performed after the surface treatment process (II) and before the inspection process. Is called. In this case, the cleaning step is a step of immersing the vulcanized rubber molded body in warm water having a temperature exceeding 40 ° C. and not higher than 100 ° C., and the cleaning step will be described in detail later. Since the second step of the step (II) can be applied, there is an advantage that the manufacturing process of the rubber product can be simplified.

The surface treatment step (II) includes a first step of applying a treatment liquid having a temperature of 40 ° C. or less to the surface of the vulcanized rubber molded body, and heating of the treatment liquid attached to the surface of the vulcanized rubber molded body through the first step. And a second step of performing cleaning.

1st process This process is a process of making a process liquid adhere to the surface of a vulcanized rubber molding.
The method of attaching (contacting) the treatment liquid having a temperature of 40 ° C. or less to the surface of the rubber molded body is not particularly limited, but the method of immersing the rubber molded body in the treatment liquid or the method of spray-coating the treatment liquid on the rubber molded body There are a method of brushing the treatment liquid on the rubber molded body, a method of pouring the treatment liquid on the rubber molded body, etc., but the work is simple, the effect can be obtained in a short time, and many rubber moldings Immersion treatment is preferred from the viewpoint that the body can be uniformly treated at once. In addition, the temperature of the treatment liquid is preferably 1 ° C. or higher and 40 ° C. or lower, more preferably 20 ° C. or higher and 40 ° C. or lower, and particularly preferably 20 ° C. or higher and 30 ° C. or lower. If it is lower than 1 ° C., the solubility of dichlorocyanurate in an aqueous solvent tends to decrease and the coagulation of the treatment liquid may occur.

In the case of the immersion treatment, the immersion time is preferably about 1 second to 10 minutes, more preferably about 5 minutes to 10 minutes. When the immersion time exceeds 10 minutes, the surface treatment hardly proceeds further, and 1 second. If it is less than 1, the treatment liquid does not adhere sufficiently to the surface, and it tends to be difficult to obtain a sufficient effect.

Second Step This step is a step for effecting the surface treatment, and heating and washing of the treatment liquid adhering to the surface of the vulcanized rubber molded body is performed. In addition, the heating temperature of a process liquid exceeds 40 degreeC and 100 degrees C or less is suitable.
Specific examples of the second step include the following aspects.
(A) A mode in which a vulcanized rubber molded body having a treatment liquid attached to the surface is immersed in warm water having a temperature exceeding 40 ° C and not more than 100 ° C.
(B) The vulcanized rubber molded body with the treatment liquid adhering to the surface is placed in an oven set to a temperature exceeding 40 ° C. and not higher than 100 ° C. (heating) and then heated, and then vulcanized rubber molding is performed. A mode in which the body is washed with warm water.

In the case of the embodiment (A), the vulcanized rubber molded product with the treatment liquid adhering to the surface is immersed in warm water having a temperature exceeding 40 ° C. and not higher than 100 ° C., so that the vulcanized rubber molded product is heated with warm water in warm water. The treatment liquid adhering to the surface is heated to react with the vulcanized rubber molded body, and the treatment liquid is washed away from the surface of the vulcanized rubber molded body by continuing the immersion. When the temperature of the hot water is 40 ° C. or lower, the reaction between the treatment liquid and the vulcanized rubber molded article does not proceed sufficiently, and a sufficient surface treatment effect cannot be obtained. On the other hand, when the temperature of the hot water exceeds 100 ° C., the evaporation of the hot water becomes intense and the practicality is lost. In order to sufficiently advance the reaction between the treatment liquid and the vulcanized rubber molded product, the temperature of the hot water is preferably 50 ° C. to 70 ° C.

The immersion time is preferably about 1 second to 10 minutes, more preferably about 2 minutes to 8 minutes, and particularly preferably about 5 to 7 minutes. If it is less than 1 second, the surface treatment effect tends to be difficult to obtain, and if it exceeds 10 minutes, it is difficult to obtain a further effect.

Here, the warm water is, for example, heated tap water, industrial ion-exchanged water or the like, and is not particularly limited, but industrial ion-exchanged water is preferable because it is not easily affected by impurities.

In the case of the mode (B), the surface of the vulcanized rubber molded body is obtained by placing the vulcanized rubber molded body with the treatment liquid attached to the surface in an oven set to a temperature of 40 ° C. or higher and 100 ° C. or lower. The treatment liquid adhering to is heated and the reaction with the vulcanized rubber molded body proceeds. The temperature in the oven is preferably 50 ° C to 70 ° C. The heating time in the oven is not particularly limited, but is preferably about 1 second to 30 minutes, and more preferably about 10 seconds to 10 minutes.

In washing with hot water performed after heating in an oven, hot water is sprayed or poured on the surface of the rubber molded body, or the rubber molded body is immersed in warm water. The temperature of the hot water is not particularly limited, but it is more than 40 ° C., preferably 100 ° C. or less, and more preferably 50 ° C. to 70 ° C. When immersed in warm water, the immersion time is preferably about 1 second to 3 minutes, particularly preferably 30 seconds to 1 minute.

In the surface treatment step (II), after the second step, the vulcanized rubber molded body is naturally dried at room temperature (1 to 30 ° C.).

The treatment liquid of the present invention exhibits an excellent anti-adhesive property imparting effect on a vulcanized rubber molded product, and also has an effect of imparting low friction to the surface of the vulcanized rubber molded product. Therefore, (i) the surface treatment process is performed after the rubber molding production process (that is, after the vulcanization molding process) and before the finishing process, and / or (ii) after the finishing process and before the inspection process. As a result, adhesion of rubber products (vulcanized rubber moldings) in the inspection process and the packaging process is prevented, and the inspection process and the packaging process. As a result, the handleability of rubber products (vulcanized rubber moldings) can be improved, and as a result, the production efficiency of rubber products can be improved.

In particular, when the rubber product is a rubber product manufactured from a rubber composition containing a component that is likely to cause precipitation (bloom, bleed, etc.), precipitation occurs immediately after the rubber molded body preparation step (ie, vulcanization molding step). The effect of suppressing the subsequent precipitation, that is, the finishing process, the inspection process, the packaging process, and the like during storage and transportation after the packaging process by performing the surface treatment process on the vulcanized rubber molded body that has not been There is. Therefore, the method of the present invention is useful in producing a rubber product from a rubber composition having a compounding composition in which additive components (bloom, bleed, etc.) are likely to precipitate from the rubber molded body. As an example of a rubber composition having a compounding composition in which precipitation (bloom, bleed, etc.) of the additive component from the rubber molded body is likely to occur, for example, the following rubber composition A can be mentioned.

(Rubber composition A)
NBR: 100 parts by weight Zinc oxide: 1 to 10 parts by weight Stearic acid: 1 to 10 parts by weight Filler (carbon; SRF carbon): 20 to 120 parts by weight Plasticizer (DOP): 1 to 40 parts by weight Crosslinker (sulfur) ): 1 to 10 parts by weight Vulcanization accelerator: 1 to 10 parts by weight

In addition, since the treatment liquid imparts low friction to the surface of the rubber molded body without deteriorating the physical properties of the rubber molded body, a rubber having a high friction coefficient against a metal surface such as nitrile rubber (NBR) is used. In an embodiment in which a sealing material (rubber seal) is produced from a rubber composition as a base component, a sealing material (rubber seal) having excellent low friction against a metal surface without reducing the extensibility of the sealing material (rubber seal). Can be manufactured efficiently. Therefore, the method of the present invention is particularly suitable as a method for producing a sliding part sealing material (rubber seal).

The method of the present invention can be applied to the production of various rubber products in various industrial fields. For example, automotive weather strips; automotive hoses (for example, brake hoses, radiator hoses, heater hoses, air cleaner hoses, etc.); Hose; gas hose; sealing material for building materials (for example, gasket, air tight, joint material, door stopper, etc.); sealing material for automotive seal (for example, O-ring, RL (radial lip), seal ring, etc.); Seals for construction machinery and hydraulic equipment seals (for example, O-rings, O-rings for cap seals, U-packings, rotary shaft seals, wear rings, D-rings, RL seals, etc.); Piston packing, rod packing, X ring, etc.); Seal for vacuum / semiconductor device seal Wood; Industrial sealing of the sealing member (cap seal ring and the like) are useful in the manufacture of rubber products, such as.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples.

Examples 1 to 3
(Preparation of treatment solution)
Three types of treatment liquids were prepared which consisted of aqueous solutions having a dissolution amount (concentration) of sodium dichloroisocyanurate of 2% by weight, 5% by weight and 10% by weight.

(sample)
A molded body obtained by vulcanizing and molding the rubber component into a sheet made of NBR was processed to a size of 50 mm (length) × 20 mm (width) × 2 mm (thickness).

(Processing method)
Treatment method 1: The test piece was immersed in a treatment solution heated to 25 ° C. for a predetermined time (1 minute, 5 minutes, 10 minutes), then washed and dried to perform surface modification.

Treatment method 2: The above test piece was immersed in a treatment solution heated to 60 ° C. for a predetermined time (1 minute, 5 minutes, 10 minutes), then washed and dried to perform surface modification.

Comparative Example 1
Surface modification was carried out in the same manner as in Example except that a treatment liquid having a dissolution amount (concentration) of trichloroisocyanuric acid in which trichloroisocyanuric acid was dissolved in ethyl acetate (EA) was 2% by weight was prepared.

The following evaluation tests were performed on the rubber members (samples) of Examples 1 to 4 and Comparative Example 1 described above.

[Evaluation test]
(1) Friction test (measurement of static friction coefficient and dynamic friction coefficient)
A surface property measuring instrument manufactured by HEIDON was used with reference to JIS-K7125. Apply a ball indenter (SUS304) to the test piece (arbitrary size) on the horizontal test table and apply a load of 100 g to the contact point, and the coefficient of friction between the ball indenter and the test piece when the test piece is moved horizontally at 75 mm / min. It was measured.

(2) Anti-adhesion test When the treated surfaces of the test pieces are brought into contact with each other, a load of about 1 kg is applied for about 5 minutes from the top, and when the load is removed, the test pieces adhere to each other and give some vibration. If it does not separate at all even if it shakes or shakes, it is impossible (×), but it adheres, but if it is lightly shaken or shaken, it can be separated (△), and it does not adhere (○ ).

(3) Stretchability test The test piece is stretched by about 100% to 150%, and the surface is visually observed to make cracks impossible (×). What was observed when observed with a microscope (200 times) was acceptable (Δ), and what was not observed even at 200 times was judged good (◯).

Tables 1 to 3 below show the test results.

Example 4
100 parts by weight of nitrile rubber as a rubber material, 0.5 parts by weight of sulfur as a crosslinking agent, 60 parts by weight of carbon black as a filler, 1.5 parts by weight of a crosslinking accelerator (TT: tetramethylthiuram disulfide), processing 1 part by weight of auxiliary agent (stearic acid) and 5 parts by weight of plasticizer (DOP) were put into a Banbury mixer, and then vulcanized and formed into a sheet shape, 50 mm (length) x 20 mm (width) x 2 mm (thickness) A) test piece was prepared. This test piece was immersed for 10 minutes in a treatment liquid at 25 ° C. composed of an aqueous solution having a dissolution amount (concentration) of sodium dichloroisocyanurate of 2% by weight. After immersion, the sample was taken out from the tank, immersed (washed) in 60 ° C. ion-exchanged water for 60 seconds, taken out, dried naturally, and dried, and then subjected to the evaluation test.

Example 5
The temperature of the treatment liquid was set to 60 ° C., and the same as Example 4 except that the treatment liquid was immersed in the treatment liquid at 60 ° C. for 5 minutes.

Example 6
The same procedure as in Example 4 was performed except that the solution (concentration) of sodium dichloroisocyanurate was immersed in a treatment solution at 60 ° C. composed of an aqueous solution of 10% by weight for 5 minutes.

Comparative Example 2
The processing solution was the same as Example 4 except that the amount (concentration) of trichloroisocyanuric acid obtained by dissolving trichloroisocyanuric acid in ethyl acetate (EA) was changed to 2% by weight.

Comparative Example 3
The same specimen as in Example 4 was used except that the surface treatment was not performed.

Table 4 below shows the test results of Examples 4 to 6 and Comparative Examples 2 and 3.

From the results of Table 4 above, if the treatment liquid is a solution in which dichloroisocyanurate is dissolved in an aqueous solvent, the low rub resistance and adhesion can be prevented without reducing the extensibility of the vulcanized rubber molded article. It can be seen that sex can be imparted. Therefore, after the rubber molded body production step for producing the vulcanized rubber molded body, the surface of the vulcanized rubber molded body is treated with a treatment liquid composed of a solution in which dichloroisocyanurate is dissolved in an aqueous solvent. It has been clarified that the rubber product having the desired physical properties (physical properties) can be efficiently produced.

Example 7
100 parts by weight of nitrile rubber as a rubber material, 0.5 parts by weight of sulfur as a crosslinking agent, 60 parts by weight of carbon black as a filler, 1.5 parts by weight of a crosslinking accelerator (TT: tetramethylthiuram disulfide), processing 1 part by weight of auxiliary agent (stearic acid) and 5 parts by weight of plasticizer (DOP) were put into a Banbury mixer, and then vulcanized and formed into a sheet shape, 50 mm (length) x 20 mm (width) x 2 mm (thickness) A) test piece was prepared. This test piece was immersed for 10 minutes in the treatment liquid of the washing tank which accommodated the 25 degreeC treatment liquid which consists of aqueous solution whose dissolution amount (concentration) of sodium dichloroisocyanurate is 2 weight%. After the immersion, the test piece was taken out from the tank, immersed in 60 ° C. ion exchange water for 60 seconds (washed), taken out, naturally dried, and dried, and then the evaluation test was performed.

Example 8
Example except that the temperature of the treatment liquid was set to 30 ° C., the test piece was immersed in the treatment liquid at 30 ° C. for 5 minutes, taken out from the bath of the treatment liquid, and the test piece was immersed in ion exchange water at 75 ° C. for 2 minutes. Same as 7.

Example 9
The test piece is immersed in a treatment liquid at 35 ° C. made of an aqueous solution having a dissolution amount (concentration) of sodium dichloroisocyanurate of 10% by weight for 1 minute, taken out from the tank of the treatment liquid, and the test piece is placed in ion exchange water at 65 ° C. for 8 minutes. The same as Example 7 except that it was immersed for a minute.

Comparative Example 4
The treatment solution was the same as that of Example 7 except that the treatment amount of the trichloroisocyanuric acid in which trichloroisocyanuric acid was dissolved in ethyl acetate (EA) was changed to 2% by weight.

Comparative Example 5
The same specimen as in Example 7 was used except that the surface treatment was not performed.

Table 5 below shows the test results of Examples 7 to 9 and Comparative Examples 4 and 5.

From the results of Tables 4 and 5 above, the treatment liquid composed of a solution in which dichloroisocyanurate is dissolved in an aqueous solvent is used to reduce the friction property without reducing the extensibility of the rubber seal as a vulcanized rubber molded body. It can also be seen that adhesion can be imparted. Therefore, after the rubber molded body production step for producing the vulcanized rubber molded body, by performing the process of treating the surface of the vulcanized rubber molded body with such a treatment liquid, it is possible to prevent adhesion between the rubber molded bodies, It became clear that rubber products with the desired physical properties (physical properties) can be produced efficiently.

This application is based on Japanese Patent Application Nos. 2014-066908, 2014-220218, and 2015-003218 filed in Japan, the contents of which are incorporated in full herein.

Claims

A surface treatment solution for rubber products consisting of a solution of dichloroisocyanurate dissolved in an aqueous solvent.
The surface treatment solution according to claim 1, wherein the dichloroisocyanurate is an alkali metal dichloroisocyanurate.
The surface treatment solution according to claim 1, wherein the dichloroisocyanurate is sodium dichloroisocyanurate.
The surface treatment solution according to any one of claims 1 to 3, wherein the concentration of dichloroisocyanurate in the solution is 2 to 20% by weight.
The surface treatment liquid according to any one of claims 1 to 4, which is a solution heated to 50 to 70 ° C.
The surface treatment liquid according to any one of claims 1 to 5, wherein the rubber product is a rubber seal.
The surface treatment liquid according to claim 6, wherein the rubber seal contains nitrile rubber (NBR).
The surface treatment liquid according to claim 6, wherein the rubber seal is a rubber seal for a sliding portion.
A method for modifying the surface of a rubber product, comprising applying the surface treatment liquid according to any one of claims 1 to 5 to the surface of the rubber product.
The method according to claim 9, wherein the surface treatment liquid is heated to 50 to 70 ° C and applied to the surface of the rubber product.
The method according to claim 9 or 10, comprising immersing the rubber product in the surface treatment liquid.
The method according to claim 11, wherein the immersion time is 1 to 30 minutes.
The method according to any one of claims 9 to 12, wherein the rubber product is a rubber seal.
The surface of the vulcanized rubber molded body is prepared by using a treatment liquid at 20 to 70 ° C. comprising a solution in which dichloroisocyanurate is dissolved in an aqueous solvent after the rubber molded body producing step for producing a vulcanized rubber molded body from the rubber composition. A method for producing a rubber product, comprising a surface treatment step (I) for performing treatment.
After the rubber molded body manufacturing process, a finishing process for removing unnecessary portions from the vulcanized rubber molded body obtained through the rubber molded body manufacturing process and an inspection process for performing an appearance inspection of the vulcanized rubber molded body that has undergone the finishing process are included. Or, in addition to the finishing step and the inspection step, further includes a packaging step of packaging the vulcanized rubber molded body that has undergone the inspection step,
The surface treatment step (I) is performed in (i) a period after the rubber molded body preparation step and before the finishing step, and / or (ii) after the finishing step and before the inspection step. A method for producing a rubber product as described in 1.
In the case of having a surface treatment step (I) after the finishing step and before the inspection step, the washing step and the drying step are included after the surface treatment step (I). 16. The method of claim 15, wherein
The method according to any one of claims 14 to 16, wherein the surface treatment step (I) of applying the treatment liquid to the surface of the rubber molded body is a step of immersing the rubber molded body in the treatment liquid.
The method according to claim 17, wherein the immersion time is 10 seconds to 30 minutes.
Instead of surface treatment step (I),
A first step of applying a treatment liquid of 40 ° C. or less comprising a solution of dichloroisocyanurate in an aqueous solvent to the surface of the vulcanized rubber molded body, and heating and washing of the treatment liquid adhered to the surface of the vulcanized rubber molded body The method for producing a rubber product according to claim 14, further comprising a surface treatment step (II) including a second step of performing the step.
The method according to claim 19, wherein the first step is a step of immersing the vulcanized rubber molded body in a treatment liquid having a temperature of 40 ° C or lower.
The method according to claim 20, wherein the immersion time is 1 second to 10 minutes.
The method according to any one of claims 19 to 21, wherein the heating temperature of the treatment liquid in the second step is more than 40 ° C and not more than 100 ° C.
The second step is a step of immersing the vulcanized rubber molded body having the treatment liquid adhered to the surface through the first step in warm water having a temperature of more than 40 ° C and not more than 100 ° C. The method of any one of Claims.
The method according to claim 23, wherein the immersion time is 1 to 10 minutes.
After the rubber molded body manufacturing process, a finishing process for removing unnecessary portions from the vulcanized rubber molded body obtained through the rubber molded body manufacturing process and an inspection process for performing an appearance inspection of the vulcanized rubber molded body that has undergone the finishing process are included. Or, in addition to the finishing step and the inspection step, further includes a packaging step of packaging the vulcanized rubber molded body that has undergone the inspection step,
The surface treatment step (II) is performed in (i) a period after the rubber molded body production step and before the finishing step, and / or (ii) after the finishing step and before the inspection step. The method according to any one of 1 to 22.
After the rubber molded body manufacturing process, a finishing process for removing unnecessary portions from the vulcanized rubber molded body obtained through the rubber molded body manufacturing process and an inspection process for performing an appearance inspection of the vulcanized rubber molded body that has undergone the finishing process are included. Or, in addition to the finishing step and the inspection step, further includes a packaging step of packaging the vulcanized rubber molded body that has undergone the inspection step,
24. The surface treatment step (II) is performed in (i) a period after the rubber molded body preparation step and before the finishing step, and / or (ii) after the finishing step and before the inspection step. Or the method of 24.
In the case of having a cleaning process and a drying process before the inspection process, and having a surface treatment process (II) after the finishing process and before the inspection process, the temperature of the cleaning process exceeds 40 ° C. and 100 ° C. or less. 27. The method according to claim 26, wherein the vulcanized rubber molded body is immersed in the warm water and applied to the second step of the surface treatment step (II).
The rubber composition is nitrile rubber (NBR), hydrogenated nitrile rubber (H-NBR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), butyl rubber (IIR). ), Natural rubber (NR), and ethylene-propylene-diene rubber (EPDM), one or more rubbers selected from the group consisting of additives are blended. The method described.
28. The method according to any one of claims 14 to 27, wherein the rubber composition is a knuryl rubber composition in which an additive is blended with nylyl rubber.
The method according to any one of claims 14 to 29, wherein the rubber product is a rubber seal.