JP2008201973A - Industrial rubber roll composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an industrial rubber roll composition containing EPDM as a main component, which causes no deterioration of abrasion resistance and processibility even when containing reclaimed rubber. <P>SOLUTION: The industrial rubber roll composition is a sulfur vulcanization type rubber roll composition composed mainly of an ethylene-propylene-diene copolymer, wherein the sulfur vulcanization type industrial rubber roll composition comprises 5-40 wt.% of an ethylene-propylene-diene copolymer-based reclaimed rubber relative to the rubber component. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an industrial rubber roll composition. In particular, the present invention relates to a rubber composition containing EPDM as a main component, in which wear resistance and workability do not decrease even when recycled rubber is contained.

  A rubber roll is a roll manufactured by adhesively coating a rubber fabric on a metal core such as iron and then vulcanizing. Generally, an adhesive is applied to a metal core, and a rubber fabric sheet is formed thereon. Is manufactured by a method in which a rubber cloth is extruded in a ribbon shape by an extruder and wound around a metal core. Such a rubber roll is used for various uses such as paper making, iron making, and printing. Among these, industrial rubber rolls are used for producing films, printing, iron making, paper making and the like. In addition, an industrial rubber roll means what excludes what is called a small roll for OA.

  Industrial rubber rolls are required to have characteristics such as wear resistance, chemical resistance, oil resistance, ozone resistance, heat resistance, and pressure resistance depending on the intended use. In particular, so-called EPDM (ethylene-propylene-diene rubber) -based blends in which ethylene-propylene-diene rubber is blended are generally applied to industrial rubber rolls that require chemical resistance. However, the disadvantages of blending EPDM are generally poor wear resistance and poor workability during production.

  In EPDM-based blending, improving the wear resistance of manufactured rubber rolls has been a big problem from the past. For this purpose, polymerizing EPDM polymer, increasing the amount of reinforcing filler, carbon species, silica species, etc. Various studies have been made to improve wear resistance by making fine particles. However, these means have a problem that the rubber dough becomes hard and has the disadvantage of poor processability during production. That is, the current state of the EPDM-based rubber roll is that there is no sufficient means to achieve both wear resistance and improved workability.

On the other hand, in recent years, interest in environmental issues is increasing, and movements such as recycling for the recycling of materials are progressing in the general industry. In particular, in the tire industry, materials are reused by converting used tires into crushed rubber and blending them in small amounts. It has been proposed that such a regenerated rubber is usually produced by destroying the crosslinked structure of the vulcanized rubber and used for the same purpose as the unvulcanized rubber. Such recycled rubber has many problems in terms of both workability and quality, such as fracture elongation, reduced strength, and poor compression set as quality characteristics after vulcanization. It has been used only on athletic pavements). For example, it is conventional to convert used tire rubber into recycled rubber and use it as a raw material for products such as roads, playgrounds, and mats, and to use used tire rubber as a fuel for cement kilns for heat recycling. (See, for example, the website of Muraoka Rubber Co., Ltd.)
In addition, attempts to regenerate and use vulcanized rubber such as tires have been made in recent years (for example, Patent Document 1). According to such a technique, it is described that a rubber composition having excellent physical properties can be obtained.

  However, in the field of rubber rolls, there has been no example of taking out rubber from a used product roll and reusing this rubber. This is because there are many problems in workability and performance when rubber is reused. Industrial rubber rolls manufactured using recycled rubber have drawbacks that there are many processing problems such as poor unity when kneading rubber, easy perforation of fabric, and poor skin. Therefore, in the field of industrial rolls, it is desired to develop technology that can be recycled as recycled rubber using vulcanized rubber.

JP 2006-241184 A

  Accordingly, an object of the present invention is to provide an industrial rubber roll composition containing EPDM as a main component, in which wear resistance and workability do not deteriorate even when recycled rubber is contained.

In order to achieve the above object, the present inventor has intensively studied, and as a result, obtained the knowledge that the above object can be achieved by using an industrial rubber roll composition having a specific composition, and completed the present invention. The present invention has been made based on the above object, and is a sulfur vulcanized rubber roll composition comprising an ethylene-propylene-diene copolymer as a main component, and an ethylene-propylene-diene copolymer-based recycled rubber. Is a sulfur vulcanized industrial rubber roll composition containing 5 to 40% by weight of the rubber component.
The present invention also provides an industrial rubber roll formed by wrapping the rubber roll composition on a shaft core material and vulcanizing it.

  Industrial Applicability According to the present invention, an industrial rubber roll composition containing EPDM as a main component, in addition to having good wear resistance even when recycled rubber is contained, has good adhesion and moldability during production. Is provided. In addition, according to the present invention, an industrial rubber roll composition that can contribute to recycling, industrial waste reduction, and the like is provided by using recycled rubber.

Hereinafter, first, the industrial rubber roll composition of the present invention will be described.
The industrial rubber roll composition of the present invention is a sulfur vulcanized rubber roll composition comprising an ethylene-propylene-diene copolymer as a main component, wherein an ethylene-propylene-diene copolymer recycled rubber is used as a rubber component. 5 to 40% by weight.

The industrial rubber roll composition of the present invention is a sulfur vulcanized industrial rubber roll composition.
The industrial rubber roll composition of the present invention means a composition for producing an industrial rubber roll by sulfur vulcanization. That is, the industrial rubber roll composition of the present invention is a composition for producing an industrial rubber roll by sulfur vulcanization using a sulfur-containing vulcanization accelerator.

  The industrial rubber roll composition of the present invention contains an ethylene-propylene-diene copolymer as a main component. In the present specification, an ethylene-propylene-diene copolymer as a main component means that 50% by weight or more of the rubber component contained in the industrial rubber roll composition is an ethylene-propylene-diene copolymer (hereinafter referred to as “ethylene-propylene-diene copolymer”). It includes an ethylene-propylene-diene copolymer-based recycled rubber as described. Preferably, the ethylene-propylene-diene copolymer is 70% by weight or more of the rubber component, more preferably 80% by weight or more, and still more preferably 90% by weight or more. In the industrial rubber roll composition of the present invention, 5 to 40% by weight of the rubber component is ethylene-propylene-diene copolymer recycled rubber.

The ethylene-propylene-diene copolymer (EPDM copolymer) -based recycled rubber refers to a rubber obtained by subjecting a vulcanized EPDM rubber to a recycled rubber treatment. Recycled rubber treatment is a rubber roll containing vulcanized EPDM rubber, which is cut into ribbons, cut into small chips, and then crushed into finely pulverized forms using a roll. It means that an agent is added and heat-treated at a temperature of 180 ° C. or higher to cut the crosslinked portion of the rubber. This treatment is a generally known method for chemically regenerating rubber. The recycled rubber used in the present invention is generally produced by a chemical treatment method, but is not limited to the production method, and can be used by any production method. is there. The industrial rubber roll composition of the present invention contains an EPDM copolymer as a main component and contains 5 to 40% by weight of a rubber component of an EPDM copolymer-based recycled rubber. The blending ratio of the EPDM copolymer-based recycled rubber is preferably 10 to 20% by weight, and the optimum amount varies depending on which of quality and processability is prioritized.
When the blending ratio of the EPDM copolymer-based recycled rubber is less than 5% by weight of the rubber component, the effect of improving the wear resistance is small. On the other hand, when the blending ratio exceeds 50 parts by weight, the workability (gum of rubber, fabric skin) , Shrinkage, etc.), and the rubber rupture strength and elongation of the vulcanizate are deteriorated.

  The industrial rubber roll composition of the present invention preferably contains a phenol resin, terpene resin or terpene phenol copolymer resin having a solubility coefficient (SP value) of 8 to 10 and a molecular weight of 900 or less. An example of the phenolic resin is a novolac type phenol resin. The novolac type phenol resin used in the present invention is obtained by condensation polymerization of phenol or modified phenol and formaldehyde. Specific examples include straight phenol resins, alkyl-substituted phenol resins, and oil-modified phenol resins.

The terpene resin includes a terpene monomer polymer and a polymer containing the second component in the polymer chain. Specifically, in addition to the terpene resin, a styrene terpene resin, a phenol-modified terpene resin. Further, hydrogenated terpene resins obtained by hydrogenating these resins are included.
The terpene phenol resin is (1) a cyclic terpene phenol resin obtained by copolymerizing a cyclic terpene compound and phenols, and (2) phenol to the cyclic terpene compound and phenol for one molecule of the cyclic terpene compound. Cyclic terpene-containing phenolic compound added at a ratio of two molecules, (3) cyclic terpene skeleton containing (1) cyclic terpene phenolic resin of (1) and (2) cyclic terpene-containing phenolic compound (4) A cyclic terpene skeleton-containing phenol resin obtained by condensation reaction of a cyclic terpene skeleton-containing phenol compound obtained by adding one molecule of phenols to one molecule of a cyclic terpene compound and an aldehyde. Can be mentioned.

The phenol resin, terpene resin or terpene phenol copolymer resin has a solubility coefficient (SP value) of 8 to 10, preferably 8 to 9. It is preferable to use a phenol resin, terpene resin or terpene phenol copolymer resin having a solubility coefficient in the above-mentioned range because it exhibits compatibility with the EPDM copolymer. The molecular weight of the phenol resin, terpene resin or terpene phenol copolymer resin is 900 or less, preferably 800 to 900.
Moreover, the blending amount of the phenol resin, terpene resin or terpene phenol copolymer resin is preferably 5 to 16 parts by weight, more preferably 10 to 15 parts by weight with respect to 100 parts by weight of the rubber component. is there. When the blending amount of the phenol resin, terpene resin or terpene phenol copolymer resin is less than 5 parts by weight with respect to 100 parts by weight of the rubber component, the polymer dispersibility of the blended fabric of rubber roll, kneaded skin, tackiness, etc. In some cases, the effect of improving workability is too small, and when it exceeds 20 parts by weight, the vulcanization reaction rate and compression set resistance may be lowered, causing problems in practice.

The industrial rubber roll composition of the present invention contains a porous inorganic filler having an average particle diameter of 2 to 6 μm, an oil absorption of 30 to 70 ml / g, and a specific surface area of 8 to 16 cm ² / g. It is preferable to make it. The average particle diameter of the porous inorganic filler is preferably 2 to 4 μm, the oil absorption is preferably 40 to 60 ml / g, and the specific surface area is preferably 10 to 14 cm ² / g.
By including such a porous inorganic filler, the effect of preventing fabric cracking during processing, which is a drawback of using recycled rubber, is improved. In the present specification, the dough cracking means a phenomenon in which when the dough is made into a sheet, a hole is formed in the sheet or the green elongation is lowered. It also has the role of improving shrinkage.

  As the porous inorganic filler, an anhydrous aluminum silicate-based condensate composed of fine-particle spherical quartz and plate-like kaolinite is preferably used. The inorganic filler preferably contained in the industrial rubber roll composition of the present invention is a surface treated with a silane coupling agent. There is no restriction | limiting in particular in the method of surface-treating an inorganic filler with a silane coupling agent, It can implement by a conventionally well-known method. As a method of surface-treating an inorganic filler with a silane coupling agent, for example, stirring an untreated inorganic filler, a method of dropping or spraying a silane coupling agent, a silane coupling agent dissolved in an organic solvent, Examples include a method of adding an inorganic filler while mixing the organic solvent in which the silane coupling agent is dissolved, mixing the two, and then drying.

Content of a porous inorganic filler is 5-16 weight part with respect to 100 weight part of said rubber components, Preferably it is 8-12 weight part.
If the content of the porous inorganic filler is less than 5 parts by weight with respect to 100 parts by weight of the rubber component, the above-mentioned effects may not be obtained. The compression set may be reduced, and the wear resistance may be reduced.

  The industrial rubber roll composition of the present invention may contain a vulcanization accelerator. As the vulcanization accelerator, those described below can be used. The amount of sulfur is usually 1.5 to 8 parts by weight per 100 parts by weight of the rubber component of the industrial rubber roll composition, and varies depending on the desired hardness. As the vulcanization accelerator to be blended with sulfur, the following organic accelerators can be used.

  Examples of the organic accelerator include thiazole vulcanization accelerators such as 2-mercaptobenzothiazole and N-cyclohexyl-2-benzothiazolesulfene, and aliphatic first compounds such as n-butylamine, tert-butylamine and propylamine. Oxidation condensate of amine and 2-mercaptobenzothiazole, oxidative condensate of aliphatic secondary amine such as dicyclohexylamine, pyrrolidine, piperidine and 2-mercaptobenzothiazole, alicyclic primary amine and 2-mercaptobenzothiazole Sulfenamide-based vulcanization accelerators such as oxidative condensates with morpholine compounds and 2-mercaptobenzothiazole, tetramethylthiuram monosulfide (TMTM), tetramethylthiuram disulfide (TMTD), Tetraethylthiuramdimonos Thiuram vulcanization accelerators such as fido (TETD), tetrabutyl thiuram dimonosulfide (TBTD), dipentamethylene thiuram tetrasulfide (DPTT), zinc dimethyldithiocarbamate (ZnMDC), zinc diethyldithiocarbamate (ZnEDC), Dithiocarbamate vulcanization accelerators such as zinc di-n-butylcarbamate (ZnBDC) can be used.

  In particular, at least one accelerator of a thiazole vulcanization accelerator and a sulfenamide vulcanization accelerator and at least one accelerator of a thiuram vulcanization accelerator and a dithiocarbamate vulcanization accelerator are used in combination. Is preferred. This is because when at least one of thiazole vulcanization accelerator and sulfenamide vulcanization accelerator is used, the vulcanization speed is increased, and thiuram vulcanization accelerator and dithiocarbamate vulcanization accelerator are used. This is because, when at least one of them is used, the start of vulcanization is accelerated and the vulcanization can proceed efficiently.

  The amount of the vulcanization accelerator is usually 1 to 5 parts by weight per 100 parts by weight of the rubber component of the industrial rubber roll composition.

The industrial rubber roll composition of the present invention preferably has a surface electrical resistance value of 10 ⁵ to 10 ⁹ Ωcm when vulcanized, and more preferably 10 ⁵ Ωcm or less. By setting the surface electrical resistance value when vulcanized to the above range, it is possible to prevent the generation of static electricity during use of the roll. In addition, to make the surface electrical resistance value when vulcanized within the above range, It is preferable to mix FEF grade carbon in an industrial rubber roll composition. In addition, the compounding quantity of FEF grade carbon becomes like this. Preferably it is 60 weight% or more with respect to the total weight of an industrial rubber roll composition. The greater the amount of FEF grade carbon blended, the lower the electrical resistance value.

  The industrial rubber roll composition of the present invention has a compression set when vulcanized is preferably 60% or less, and more preferably 20% or less. By setting the compression set within the above range, the sag durability during roll use can be maintained. In addition, in order to set the compression set when vulcanized to the above range, it can be carried out by controlling the amount of carbon in the industrial rubber roll composition. A solubility coefficient (SP value) of 8 to 10 and a molecular weight of 900 or less can be blended with a phenol resin, a terpene resin or a terpene phenol copolymer resin and sulfur vulcanized.

  You may mix | blend the additive normally mix | blended with the rubber roll composition in the industrial rubber roll composition of this invention. Examples of the additive include carbon (FEF), zinc oxide, stearic acid, and a plasticizer. Examples of the plasticizer include Diana process oil in naphthenic oil.

  Further, the industrial rubber roll composition of the present invention may be blended with a resin other than the EPDM copolymer and the EPDM copolymer-based recycled rubber described above. Examples of such a resin include ethylene ethyl acrylate resin, ethylene vinyl acetate resin, polyethylene resin, polypropylene resin, ethylene-methacrylic acid copolymer resin, styrene thermoplastic elastomer, polyester thermoplastic elastomer, and the like. When blending such a resin, the content is preferably 10% by weight or less based on the total amount of the EPDM copolymer and the EPDM copolymer-based recycled rubber. When a large amount of the above resin is blended, the compatibility with the EPDM copolymer and the EPDM copolymer regenerated rubber is deteriorated, and the EPDM copolymer is difficult to finely disperse during vulcanization, and the durability and friction of the resulting industrial rubber roll are reduced. The coefficient may be likely to decrease.

  The industrial rubber roll composition of this invention is used in order to manufacture an industrial rubber roll so that it may mention later. Specifically, the industrial rubber roll composition of the present invention is used for producing an industrial rubber roll by sulfur vulcanization. The industrial rubber roll composition is vulcanized using sulfur as described above.

In order to obtain the industrial rubber roll composition of the present invention, for example, it can be obtained by kneading the above materials using a normal mixing roll, Banbury mixer, various kneaders, etc., but is not limited thereto.
The industrial rubber roll composition of the present invention produces an industrial rubber roll, that is, a rubber roll used for industrial materials and products such as films, iron making, paper making, etc. except those used for printing and OA. Can be used as a material.

Next, the industrial rubber roll of the present invention will be described.
The industrial rubber roll of the present invention is formed by covering and vulcanizing the above-described industrial rubber roll composition of the present invention on a shaft core material.
The industrial rubber roll of the present invention uses the above-described industrial rubber roll composition of the present invention as a material, is kneaded by a normal Banbury mixer, a kneader, etc., and extrudes a ribbon-shaped rubber with an unvulcanized rubber sheet or an extruder. Can be manufactured by wrapping a metal core in a spiral shape and subsequently vulcanizing with a vulcanizer. Examples of the metal core used include those generally made of iron, aluminum, stainless steel, and the like. In addition, the temperature at the time of kneading | mixing is normally Max110-150 degreeC, and time is about 10 to 30 minutes.

  The industrial rubber roll of the present invention is preferably used as a rubber roll used for industrial materials and products such as films, iron making, paper making, etc. except for those used for printing and OA, or a friction roll. Used.

Hereinafter, the present invention will be described in more detail with reference to examples. Needless to say, the scope of the present invention is not limited to such examples.
The present invention will be described in more detail with reference to examples. Needless to say, the scope of the present invention is not limited to such examples.

Production Example 1
Production of Recycled Rubber From a rubber roll vulcanized with an ethylene-propylene-diene copolymer, the rubber is cut into a ribbon shape (width: about 1 to 2 cm) and cut short (about 2 cm). The cut vulcanized rubber is pulverized with a pulverizing roll machine, and a regenerant (a mixture of petroleum hydrocarbon and coumarone indene copolymer) is added to the powder rubber and mixed with a mixer. This is heated in a steam pressure kettle (desulfurization kettle) to cut or depolymerize (desulfurize) the crosslinked portion to obtain desulfurized rubber. Next, the desulfurized rubber is passed through a deadline roll to grind the granular rubber. By performing such treatment, plasticity appears in the rubber. Finally, it passes through a strainer (a machine that removes foreign matter by passing through a wire mesh with a kind of extruder) in order to remove foreign matter in the recycled rubber. In order to make this into a final product, the refiner roll further enhances the plasticity and arranges it into a rubber sheet to make a product. These methods are generally processes for producing recycled rubber. The recycled rubber employed in the present invention is produced by the above-mentioned general method.
The recycled rubber used in the following examples is composed of 63 parts by weight of carbon (FEF), 28 parts by weight of plasticizer, 5 parts by weight of zinc oxide, 1 part by weight of stearic acid, and 100 parts by weight of EPDM as a polymer. A regeneration agent is added to sulfur-vulcanized vulcanized rubber and regenerated by the above method.

In this example, the rubber roll composition was evaluated by the following method.
(1) Kneading processability When kneading a rubber compound with a kneader, evaluation was performed by comprehensively judging chemical dispersibility such as polymer and carbon, cohesiveness of kneaded dough, and skin of the dough.
Evaluation was performed according to the following evaluation criteria.
○: Dispersibility, cohesiveness, and dough skin were at a level with no problems as a whole.
(Triangle | delta): One or more of dispersibility, unity, and dough skin was a slightly inferior level.
X: One or more of dispersibility, cohesiveness, and dough skin was at a practically problematic level.

(2) Mooney viscosity
The Mooney viscosity is to evaluate the flow characteristics of the rubber fabric, and was measured at a temperature of 100 ° C. using a Mooney viscometer (manufactured by Toyo Seiki Co., Ltd., Mooney Viscometer).
After setting the sample, the torque value after 5 minutes is measured, and the lower viscosity is judged to be good (in this case, the fluid is judged to be good). The numerical values in the table are Mooney units determined by JIS proportional to the torque value, and 8.30 Nm corresponds to 100.

(3) Formability The rubber fabric is extruded into a ribbon shape with an extruder and the ribbon is cracked around the iron core when the ribbon is wound around the iron core. Evaluate and judge. If these properties are poor, high-precision molding cannot be performed, and a ribbon-like pattern or poor fusion (streaks) between ribbons tends to occur on the roll surface after vulcanization (product failure).
Evaluation was performed according to the following evaluation criteria.
○: The ribbon edge was sharp and the tackiness at the time of winding was at a level where there was no problem.
(Triangle | delta): The ribbon edge was not sharp or the tack property at the time of winding was inferior.
X: The ribbon edge is not sharp and causes a practical problem (product defect), or the tackiness at the time of winding becomes a practical problem (product defect).

(4) Abrasion resistance A rubber sample is attached to a rotating grindstone with an Akron-type abrasion tester (Kamijima Seisakusho Co., Ltd.) at an angle of 15 degrees with respect to the rotational direction of the rotating grindstone. Was measured for the weight loss (in terms of volume) of the rubber after 1000 revolutions. It can be evaluated that the smaller the numerical value, the better the wear resistance.

(5) Wear skin The wear skin of the sample tested in (4) is observed with a microscope, and the ablation pattern interval (wave interval) due to wear is measured. It is determined that the shorter the interval, the cleaner the wear surface and the better the wear skin. The wear skin index was determined as follows.
After performing the abrasion test, the abrasion surface of the test piece was magnified 100 times and observed, and the ablation interval was measured. The smaller the interval length (wear pitch), the better the wear skin, and the interval length (width) was indexed.

(6) Fracture energy Using a tensile tester (made by Toyo Seiki Co., Ltd., strograph), measure the strength and elongation of the vulcanized rubber sample (2 mm thick slab) until breakage. Convert the amount of energy required for stress fracture. In general, the area is evaluated by multiplying fracture and fracture elongation. The larger the value, the better.

(7) Compression set A vulcanized sample having a thickness of 2 mm was cut into a strip shape (width 1 cm × length 12 cm), the sample was bent so as to overlap at the center in the length direction (angle 0), and the bent center portion (10 mm) The length was pressed with a constant load (0.2 kg / cm ² ). The sample was placed in a thermostatic bath at 130 ° C. for 6 hours and heated under pressure. After 6 hours, the sample was taken out, and at the same time the pressure-bonding force was released and allowed to cool naturally. After cooling, the set amount (crimp permanent set) angle at the center of the strip-shaped sample was measured. The greater the set angle after removing the load, the better the compression set. In the case of 180 degrees, the compression set is zero. Therefore, the evaluation was performed by calculating the compression set resistance = (180−set angle) / 180. It is judged that the smaller this value (index), the better.

(8) Surface electrical resistance
Using a DIGITAL type MΩ HITESTER (manufactured by KIOK), the surface electrical resistance value (Ωcm) of the vulcanized rubber sample at 250 V is measured. It is judged that the smaller the resistance value is, the easier it is for electricity to flow and the less likely to generate static electricity.

(9) Adhesiveness After applying an adhesive (Type Lai BN or Chemlock 205/220) to an iron core with a length of 750 mmΦ and an outer diameter of 60 mm, a sheet-like rubber is formed into a spiral shape (rubber thickness 15 mm) and vulcanized. Rubber roll. After vulcanization, one section of the rubber roll was partially polished along the iron core in the length direction to a width of 20 mm and close to the iron core interface of 5 mm. After polishing, a 20 mm wide cut is made in the length direction of the iron core, the rubber is peeled off from the interface of the iron core, and the appearance is visually evaluated according to the state of the iron core interface with rubber (observation of the state with rubber) To do. When there was no peeling of the interface, it was evaluated that the adhesion was good.
The adhesion was evaluated in the following three stages.
A: There is no peeling in the length direction (the state with rubber is 100%).
B: Peeling in the length direction is partial (the state with rubber is 50% or more and less than 100%).
C: The peeling in the length direction is complete (the state with rubber is less than 50%).

(10) Shrinkability After the rubber roll sheet fabric is sheeted to 2 mm pressure with a roll, it is cut into a rectangle with a fabric width of 10 cm and a length of 25 cm, and then left to stand naturally on a table in the length direction after 5 minutes. The amount of shrinkage was measured. Evaluation was performed using the shrinkage rate (%) in the length direction after 5 minutes. The smaller the measured value, the less the shrinkage of the sheet at the time of molding, and the stable molding can be performed, so that it is judged that the workability is good.

(11) Tackiness (adhesiveness)
A 2 mm-thick rubber roll sheet fabric is fixed on a base, and a 2 mm-thick sheet fabric is wrapped around a metal roller (30Φ x width 2 mm), and then the roller is loaded at a constant load (400 g / cm ² ). After pressing for 5 seconds, the force when pulling the roller apart was measured. The measurement was performed using an adhesive force measuring machine manufactured by Meiwa Rubber Industries. It is judged that tackiness (adhesiveness) is so favorable that this measured value is large. Also, those with good tackiness (adhesiveness) are judged to have good adhesion between rubber / rubber during molding, less air entering, quality is stable, and workability is good. The

Examples 1-5, Comparative Examples 1-2
Industrial rubber loam compositions having the formulations shown in Table 1 were produced by kneading for 19 minutes at a maximum 120 ° C. in a Banbury mixer. In the following examples, all numbers in the table represent parts by weight. The obtained rubber roll composition was evaluated as described above. The results are shown in Table 2.

In Table 1, as EPDM, manufactured by JSR Co., Ltd., T7241, as EPDM recycled rubber, the recycled rubber obtained in the above production example, as FEF carbon, manufactured by Asahi Carbon Co., Ltd., # 60 As a plasticizer, Sansen 4240 (naphthenic rubber process oil, manufactured by Nippon Kosan Co., Ltd.), Acticill as manufactured by HOFMANN, PF216 (average particle size: 2.6 μm, oil absorption: 50 ml / g) , Specific surface area: 11.6 cm ² / g) As a phenol-terpene resin, a silane-based surface treated product is YS resin (manufactured by Yasuhara Chemical Co., Ltd.), an aromatic modified terpene resin (SP value: 8.4, molecular weight). : About 700), zinc oxide (2 types) manufactured by Sakai Chemical Co., Ltd. was used, and surface treatment sulfur (manufactured by Tsurumi Chemical) was used as sulfur. In Table 1, DM and M each represent a vulcanization accelerator type.
The same applies to Tables 3 and 5.

  Table 2 shows the following. It can be seen that the addition of an EPDM copolymer-based recycled rubber is effective in kneading processability, molding processability, wear resistance, and the like. The effect increases as the amount increases, but on the other hand, there is a drawback that the breaking energy decreases. Therefore, when the EPDM copolymer-based recycled rubber is added in an amount exceeding 50 parts by weight, the fracture energy level is greatly reduced, and it becomes a problem in practical use and becomes unusable, and the electric resistance value increases, which is a problem.

Examples 6-8, Comparative Examples 3-4
Industrial rubber loam compositions having the formulations shown in Table 3 were produced by kneading for 19 minutes at a maximum of 120 ° C. using a Banbury mixer. In the following examples, all numbers in the table represent parts by weight. The obtained rubber roll composition was evaluated as described above. The results are shown in Table 4.

  Table 4 shows the following. Addition of phenol / terpene resin to the system improves molding processability and tackiness, but the amount added increases, and when 20 parts by weight is reached, compression set resistance is reduced to a practically problematic level. . Also, the adhesiveness tends to decrease. When tackiness is improved, air content between ribbons is reduced and molding processability is improved. However, if the amount of the phenol / terpene resin added is increased to nearly 20 parts by weight, the compression set resistance decreases, so 4 to 16 parts by weight is practically a region where both workability and quality are compatible.

Examples 9-11, Comparative Examples 5-6
An industrial rubber loam composition having the composition shown in Table 5 was produced by kneading at a temperature of Max 120 ° C. for 19 minutes using a Banbury mixer. In the following examples, all numbers in the table represent parts by weight. The obtained rubber roll composition was evaluated as described above. The results are shown in Table 4.

  Table 4 shows the following. By adding an inorganic porous filler (acticyl) to the system, the shrinkage of the dough is improved, and at the same time, the kneadability is improved. Although there is an effect of reducing shrinkage when the added amount of the inorganic porous filler is 5 parts by weight, the compression set becomes worse when the amount is increased, so the added amount is desirably 18 parts by weight or less.

Claims (7)

A sulfur vulcanized rubber roll composition comprising an ethylene-propylene-diene copolymer as a main component, the ethylene-propylene-diene copolymer regenerated rubber containing 5 to 40% by weight of a rubber component, sulfur Vulcanized industrial rubber roll composition. The solubility coefficient (SP value) is 8 to 10 and the molecular weight is 900 or less, containing 5 to 16 parts by weight of phenol resin, terpene resin or terpene phenol copolymer resin with respect to 100 parts by weight of the rubber component. Item 2. The industrial rubber roll composition according to Item 1. A porous inorganic filler having an average particle diameter of 2 to 6 μm, an oil absorption of 30 to 70 ml / g, and a specific surface area of 8 to 16 cm ² / g is 5 to 100 parts by weight of the rubber component. The industrial rubber roll composition according to claim 1, comprising 18 parts by weight. The industrial rubber roll composition according to any one of claims 1 to 3, which has a surface electrical resistance value of 10 ⁵ Ω to 10 ⁹ Ωcm when vulcanized. The industrial rubber roll composition according to any one of claims 1 to 4, wherein the compression set when vulcanized is 60% or less. The industrial rubber roll composition according to any one of claims 1 to 5, comprising a vulcanization accelerator. An industrial rubber roll obtained by wrapping and vulcanizing the industrial rubber roll composition according to any one of claims 1 to 6 on a shaft core material.