JP2017150105A - Organic fiber cord and rubber product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic fiber cord having improved fatigue resistance of a polyester fiber and a rubber when exposed to high temperature and practically efficient adhesive force, which are not achieved in prior art.SOLUTION: There is provided an organic fiber cord having down twist and up twist, twisting coefficient of the down twist of 1000 to 2500, twisting coefficient of the up twist of 1500 to 3600, coated by an adhesive containing resorcin formalin rubber latex (RFL) after twisting and having cord compressibility ratio of 83 to 97% and RFL impregnation degree of 10 to 50%.SELECTED DRAWING: None

Description

  The present invention relates to an organic fiber cord used for tires, hoses and belts. More specifically, it has a high elastic modulus, and the heat-resistant adhesiveness, heat-resistant strength retention, and fatigue resistance when exposed to high temperatures in rubber for a long time during rubber vulcanization process and product use are remarkably improved. The present invention relates to a method for producing an organic fiber cord suitable for tires, hoses and belts.

  Since fibers such as polyester and aramid have excellent strength, elastic modulus and thermal dimensional stability, they have been widely used as reinforcing materials for rubber products such as tires, hoses and belts. However, when a reinforcing material is embedded and used in a rubber product, a load is repeatedly applied, and deterioration due to repeated expansion, compression, and bending occurs. Further, due to such deterioration, the initial properties of strength and adhesiveness are remarkably lowered, and there is a problem that it cannot be used.

  The following proposals have been made as a method for solving these problems.

  Patent Document 1 discloses a cord having an RFL adhesive impregnation degree of 3.5 to 9%.

  Patent Document 2 discloses a tire cord manufacturing method including a step of continuously pressing the twisted cord against a felt body impregnated with an adhesive composition.

  Patent Document 3 discloses a rubber in which silicon and magnesium are main constituent elements, and a silicate compound having a silicon / magnesium ratio of 1 / (0.1 to 1.0) is blended in an adhesive matrix component. A fiber adhesive composition is disclosed.

  Patent Document 4 is coated with a first treatment agent containing an aliphatic polyepoxide compound, a blocked polyisocyanate compound, and a vinylpyridine / styrene / butadiene rubber latex having a glass transition point of −30 to 0 ° C. It is a polyester fiber cord for rubber reinforcement coated with a second treating agent containing resorcin / formalin / rubber latex (RFL) as an outer layer, and the hot stretch tension at the first bath is 0.05 to 0.40 cN / A method for producing a polyester fiber cord for rubber reinforcement characterized by being treated with dTex is disclosed.

Special table 2014-530302 gazette JP 2009-138292 A Japanese Patent Laid-Open No. 9-100165 JP 2013-76186 A

  However, according to Patent Document 1, the fatigue resistance is improved, but the adhesive strength is not sufficient. According to Patent Document 2, the adhesion is sufficient, but the fatigue resistance is not improved. According to Patent Document 3, fatigue resistance is improved and adhesiveness is sufficient, but adhesive force after forced deterioration is not sufficient. According to Patent Document 4, although the adhesive force and the adhesive force after forced deterioration are sufficient and the fatigue resistance is improved, the durability while the required level is increasing is still not sufficient.

  Therefore, an object of the present invention is to provide an organic fiber cord that has improved fatigue resistance and that has practically sufficient adhesion between fiber and rubber, which could not be achieved by the above-described conventional technology.

  The present inventors diligently studied and found that the reason why the fatigue resistance is not improved is that the cord is excessively impregnated with the adhesive. In past studies, the main focus was on impregnating the inside of the fiber with an adhesive in order to ensure adhesion. When the inside of the fiber is filled with the adhesive, the adhesive hardens the cord, the movement of the filament is restricted, and the adhesive promotes chemical decomposition of the fiber to deteriorate the fatigue resistance. On the other hand, if the impregnation property of the adhesive inside the fiber is insufficient, the adhesive strength is reduced.

  That is, this invention consists of the following structures.

  (1) An adhesive having a lower twist and an upper twist, a twist coefficient of the lower twist of 1000 to 2500, a twist coefficient of the upper twist of 1500 to 3600, and various twist cords including resorcin, formalin, rubber latex (RFL) An organic fiber cord having a cord compression rate of 83 to 97% and an RFL impregnation degree of 10 to 50% inside the cord.

  (2) The organic fiber cord according to (1), wherein the organic fiber includes at least one selected from polyethylene terephthalate, nylon 66, and aramid.

  (3) The organic fiber cord according to (1) or (2), which is for rubber reinforcement.

  (4) A rubber product comprising the organic fiber cord according to any one of (1) to (3).

  According to the present invention, a fiber cord having significantly improved fatigue resistance when used in a rubber product and practically sufficient adhesion can be obtained. The rubber product reinforced with the fiber cord according to the present invention can withstand severe use for a long time when used as a tire, belt and hose.

  The present invention is described in detail below.

  The organic fiber cord of the present invention (hereinafter sometimes referred to as a cord) is a cord made of organic fibers. The organic fiber cord of the present invention can be used for various rubber members such as tires, belts, hoses and the like for automobiles, and the weight of the rubber member can be reduced and the durability can be improved.

 The organic fiber used for the organic fiber cord is preferably in the form of a multifilament. In addition, the material constituting the organic fiber includes at least one selected from polyethylene terephthalate, polyethylene naphthalate, nylon 6, nylon 66, nylon 46, polyvinyl alcohol, rayon, and aramid. It is preferable in terms of productivity.

  Further, the organic fiber used in the present invention may have been previously provided with a polyepoxide compound in the yarn making process. Examples of the polyepoxide compound that can be used in the present invention include compounds containing 0.1 g equivalent or more per 100 g of the compound in at least two epoxy groups in one molecule. Specifically, reaction products of polyhydric alcohols such as pentaerythritol, ethylene glycol, polyethylene glycol, propylene glycol, glycerol, sorbitol and halogen-containing epoxides such as epichlorohydrin, unsaturated by peroxide or hydrogen peroxide, etc. Polyepoxide compounds obtained by oxidizing compounds, such as 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexenecarboxylate, bis (3,4-epoxy-6-methyl-cyclohexylmethyl) adipate, phenol novolac type, Hydroquinone type, biphenyl type, bisphenol S type, brominated novolak type, xylene modified novolak type, phenol glyoxal type, trisoxyphenylmethane type, trisphenol PA type, bisphenol Aromatic polyepoxides such as enol-type polyepoxides. Particularly preferred are polyepoxides of sorbitol glycidyl ether type or cresol novolac type.

  These compounds are usually used as emulsions and solutions. That is, the above compound is dissolved in a solvent and used as a solution, or it is emulsified using an ordinary emulsifier such as sodium alkylbenzene sulfonate, dioctyl sulfosuccinate sodium salt, nonylphenol ethylene oxide adduct and the like, and used as an emulsion.

  The polyepoxide compound is applied together with a spinning oil agent in a process for producing organic fibers. The amount of the polyepoxide compound deposited at this time is preferably in the range of 0.1 to 5% by weight. When the adhesion amount of the polyepoxide compound is within the above range, the effect of the polyepoxide compound is sufficiently exhibited, and satisfactory adhesiveness can be obtained between the organic fiber and the rubber. Moreover, if it is the said range, a fiber will not become hard too much and a strength will not fall easily when twisting in the following process.

  The organic fiber used in the present invention is not restricted by the fineness, the number of filaments, the cross-sectional shape, etc., but usually a circular cross-section yarn of 200 to 5000 dtex, 30 to 1000 filament is used, and a 250 to 3000 dtex, 50 to 500 filament. A circular section yarn is preferred.

  The organic fiber cord of the present invention is usually obtained by twisting the above organic fiber into a raw cord (various twisted cord), and weaving the raw cord as it is or after weaving the raw cord, and then treating with an adhesive. The raw cords used for ordinary carcass tire cords are twisted in the S or Z direction, then two or three twisted cords are combined and the same number of twists are applied in the opposite direction to the twisted cord. It is what. Next, the raw cord is used as a warp, and the weft is covered with cotton yarn or the organic fiber is covered with cotton yarn to obtain a weft, which is woven into a raw fabric. Next, the ginger fabric is treated with an adhesive to obtain a dip fabric.

  On the other hand, in the case of cords for hoses and belts, apply a lower twist, combine two or three, and then apply the same number of upper twists in the opposite direction to the lower twist to form various twisted cords, and treat with the adhesive in the form of the cord And dip code.

  The organic fiber cord to which the adhesive of the present invention is applied refers to both the dip anti-dip and the dip cord.

  The organic fiber cord used in the present invention is required to be a twisted yarn cord subjected to a lower twist and an upper twist. At this time, the twist coefficient K1 of the lower twist needs to be 1000 ≦ K1 ≦ 2500, and preferably 1300 ≦ K1 ≦ 2000. If the twist coefficient of the lower twist is out of the range of 1000 ≦ K1 ≦ 2500, the RFL impregnation degree is out of the preferable range, or the fatigue resistance in the rubber is deteriorated.

  Further, the twist coefficient K2 of the upper twist needs to satisfy 1500 ≦ K2 ≦ 3600, and preferably satisfies 2000 ≦ K2 ≦ 3000. When the twist coefficient of the upper twist is out of the range of 1500 ≦ K2 ≦ 3600, the degree of RFL impregnation is out of the preferable range, or the fatigue resistance in the rubber is deteriorated.

The twist coefficient K is represented by the following formula.
K = T × D ^1/2
(K: twist coefficient, T: number of twists per unit length (times / 10 cm), D: fineness dTex)

  The cord in the present invention is a fiber cord in which the above-mentioned twisted cords are coated with an adhesive containing resorcin / formalin / rubber latex (RFL), and the cord compression rate is 83 to 97%, and the cord enters the cord. The RFL impregnation degree is 10 to 50%.

  In the present invention, the stranded cords may be subjected to primer treatment before the stranded cords are coated with an adhesive containing resorcin / formalin / rubber latex (RFL) (sometimes referred to as an RFL adhesive).

  A preferable range of the cord compression rate is 85 to 95%, and if it falls outside this range, the fatigue resistance of the cord is deteriorated. A preferable range of the RFL impregnation degree is 10 to 30%. When the degree of impregnation is less than 10%, the adhesive strength is reduced, and when the degree of impregnation exceeds 50%, the fatigue property of the cord is deteriorated. The method of adjusting the code compression ratio to 83 to 97% and the impregnation degree to 10 to 50% is not particularly limited, but an adhesive containing RFL and / or a viscosity mineral such as smectite as a primer treatment agent before RFL treatment, 1 to 7 parts by weight is added to 100 parts by weight of the solid content of the adhesive containing RFL, or 1 to 100 parts by weight of the solid content of the primer treatment agent when added to the primer treatment agent before the RFL treatment. It can be achieved by adding -10 parts by weight, and setting a tank internal tension (dipping tension), a roll pressure, and a drying tension (DRY tension) described below within specific ranges. Viscosity minerals such as smectite are not particularly limited, but smectite that is an aqueous dispersion having a thixotropy index of 2 to 10 when 1 part by weight of solid is dispersed in water is preferable.

  When performing primer treatment, it is preferable from the viewpoint of adhesiveness to add a blocked isocyanate compound, an epoxy compound, etc. as a primer treatment agent.

  The primer treatment agent is preferably added with a rubber latex from the viewpoint of improving adhesiveness. Examples of the rubber latex include natural rubber latex, butadiene rubber latex, styrene / butadiene rubber latex, vinylpyridine / styrene / butadiene rubber latex having any glass transition temperature other than those described above, nitrile rubber latex, hydrogenated nitrile rubber latex, chloroprene. Rubber latex such as rubber latex, chlorosulfonated rubber latex, ethylene / propylene / diene rubber latex can be used in combination.

  The solid content concentration of the primer treatment agent is preferably 1 to 20% by weight.

  The adhesion amount of the primer treatment agent is preferably in the range of 0.5 to 5% by weight with respect to the cord from the viewpoint of adhesion and fatigue resistance.

  As the RFL adhesive, a practical rubber adhesive can be obtained by using an RFL treating agent obtained by adding a rubber latex (L) to a commonly used resorcin-formalin initial condensate (RF).

  The RFL adhesive contains resorcin / formalin / rubber latex (RFL). Resorcin / formalin / rubber latex is a mixture of resorcin / formaldehyde precondensate and rubber latex. The resorcin / formalin / rubber latex (RFL) is preferably prepared using a resorcin / formaldehyde initial condensate obtained by initial condensation in particular under an alkali catalyst. For example, resorcin and formaldehyde are added and mixed in an alkaline aqueous solution containing an alkaline compound such as sodium hydroxide, and allowed to stand at room temperature for several hours. After the initial condensation of resorcin and formaldehyde, a rubber latex is added to the mixed emulsion. It is prepared by the method.

  As the resorcin / formaldehyde initial condensate, a resorcin / formaldehyde molar ratio of 1: 0.3 to 1: 5, preferably 1: 0.75 to 1: 2.0 is used. If the molar ratio of formaldehyde is less than the above range, the treatment cord may become sticky and may cause soiling of the processing machine. On the other hand, if the molar ratio of formaldehyde is larger than this range, the adhesive strength may decrease. There is.

  Examples of the rubber latex used for the preparation of resorcin / formalin / rubber latex include natural rubber latex, butadiene rubber latex, styrene / butadiene rubber latex, vinylpyridine / styrene / butadiene rubber latex, nitrile rubber latex, hydrogenated nitrile rubber latex, Examples include chloroprene rubber latex, chlorosulfonated rubber latex, ethylene / propylene / diene rubber latex, and the like. These can be used alone or in combination.

  In the resorcin / formalin / rubber latex, it is preferable that the compounding ratio of the resorcin / formaldehyde initial condensate and the rubber latex is 2/1 to 1/12 in terms of solid content weight. If it is out of this range, the adhesive strength may decrease.

  The solid content concentration of the RFL adhesive is preferably 3 to 30% by weight.

  The adhesion amount of the RFL adhesive is preferably in the range of 0.5 to 10% by weight with respect to the cord from the viewpoint of adhesion and fatigue resistance. If it exceeds 10% by weight, the impregnation degree may exceed 50% by weight.

  The organic fiber cord of the present invention characterized by the above has significantly improved fatigue resistance during the rubber vulcanization process and during the use of rubber products. The rubber product reinforced with the organic fiber cord according to the present invention can withstand long-term severe use when used as a tire, a belt, and a hose, and thus is extremely useful for rubber reinforcement.

  Next, the manufacturing method of the organic fiber cord of the present invention will be described. The organic fiber cord of the present invention can be obtained by applying an adhesive containing the aforementioned resorcin / formalin / rubber latex to the above-mentioned various cords. Before applying the RFL adhesive, the above-described primer treatment agent may be applied as necessary.

  The organic fiber used in the present invention is twisted to form a raw cord (twisted cord) having the above-described twist coefficient, and then the cord is woven using a loom for weaving. In the case of a hose or belt cord, the lower twisted cord or various yarn cords may be used for the next dipping step without weaving.

  The method for applying the primer treatment agent is performed by immersing the organic fiber raw cord or raw cord cocoon, followed by drying and heat treatment. The total solid content concentration of the dip solution of the primer treatment agent is 2 to 30% by weight, preferably 3 to 15% by weight. If the solid content concentration is too low, the adhesive surface tension increases, the uniform adhesion to the organic fiber surface decreases, and the resin adhesion amount decreases, which may increase the degree of impregnation of the RFL adhesive. Further, if the solid content concentration is too high, the resin adhesion amount becomes too large, so that the adhesion amount of the RFL adhesive is decreased, and the adhesive force may be lowered.

  When the primer treatment agent is applied, the organic fiber cord is dried at 70 to 150 ° C. for 0.5 to 5 minutes (hereinafter referred to as dry treatment) and then heat treated at 180 to 255 ° C. for 0.5 to 5 minutes (hereinafter hot). This is referred to as “treatment”, and a film of the primer treatment agent is formed on the fiber surface, but drying may be omitted in some cases.

  If the temperature of the heat treatment is less than 180 ° C., the adhesive is not sufficiently dried, and the rolls on the treatment process may cause solid gumming up, which may deteriorate the operational stability. On the other hand, the temperature exceeds 255 ° C. A high temperature is not preferable because the coating film formed by the treating agent formed on the fiber may be deteriorated to increase the degree of RFL impregnation, and the organic fiber may be thermally deteriorated to reduce the strength.

  In order to control the resin adhesion amount of the primer treatment agent to the organic fiber, for example, methods such as squeezing with a pressure roller, scraping with a scrubber, blowing with pressurized air, suction, etc. can be used. In order to adjust the degree of impregnation, it is preferable to use a pressure roller. When using a pressure roller, the roller pressure is preferably 0.1 to 1.0 kPa / dTex. Moreover, in order to increase the resin adhesion amount, it may be adhered a plurality of times. The cord tension when the resin is adhered is preferably about 0.05 to 0.5 cN / dTex. Moreover, the cord tension at the time of dry processing (when drying is omitted, at the time of hot processing) is preferably 0.1 to 2.0 cN / dTex. When it is within this range, the cord compression rate and the degree of impregnation can be easily controlled within a preferable range, and excellent strength can be obtained.

  When the primer treatment agent is applied as described above, an RFL adhesive containing resorcin / formalin / rubber latex is subsequently applied. When the primer treatment agent is not used, the RFL adhesive is directly attached to the various twisted cords after the lower twist and the upper twist.

  The RFL adhesive containing resorcin / formalin / latex preferably has a solid content of 3 to 30% by weight, more preferably 5 to 25% by weight. If it is less than 3% by weight, the resin adhesion amount of the dip liquid in the second bath may be insufficient, and the adhesive force may not be sufficient. If the solid content concentration exceeds 30% by weight, the storage stability of the dip solution deteriorates, the solid content aggregates and the concentration changes, and it becomes difficult to uniformly attach the dip solution to the surface of the organic fiber cord. The possibility and the degree of RFL adhesive impregnation may increase.

  The resin adhesion amount of the adhesive to the organic fiber cord is preferably in the range of 0.5 to 5% by weight, more preferably in the range of 0.7 to 4% by weight. The total resin adhesion amount in the first bath and the second bath is preferably in the range of 1.0 to 15% by weight, more preferably 1.5 to 8.0%. If the resin adhesion amount is too low, the adhesiveness may decrease. On the other hand, if the resin adhesion amount is too high, the cord may become hard and the fatigue resistance may decrease. Gum up of solid content may occur and operation stability may deteriorate.

  In order to control the amount of resin adhered to the organic fiber, for example, a method such as squeezing with a pressure roller, scraping with a scrubber, blowing with pressurized air, suction, or the like can be used. Although there is no limitation as long as it satisfies the scope of the present invention, it is preferable to use a pressure roller in terms of easy adjustment of the cord compression ratio and the RFL impregnation degree. When using the pressure roller, the roller pressure is 0.1 to 1. 0.0 kPa / dTex is preferable. In order to easily control the resin adhesion amount, the roller pressure is preferably low, more preferably 0.1 to 0.5 kPa / dtex, and further preferably 0.1 to 0.3 kPa / dtex. . It is possible to control the adhesive adhesion amount when the roller pressure is not less than the above lower limit, and the RFL soaked when the roller pressure is not more than the above upper limit is not excessively squeezed, and the code compression rate The RFL impregnation degree is in a preferable range. Moreover, in order to increase the resin adhesion amount, multiple times may be attached. The cord tension when the resin is adhered is preferably about 0.05 to 0.5 cN / dTex, more preferably 0.05 to 0.2 cN / dtex.

  The organic fiber cord to which the RFL adhesive is applied is dried at 70 to 150 ° C. for 0.5 to 5 minutes (dry treatment), then heat treated at 200 to 255 ° C. for 0.5 to 5 minutes (hot treatment), and then In order to control the physical properties of the cord, it is preferable to perform heat treatment at 200 to 255 ° C. for 0.5 to 5 minutes (hereinafter referred to as normalizing treatment). In this way, a film made of an adhesive can be formed on the fiber surface, but in some cases, drying can be omitted. If the temperature of the hot treatment and normalization treatment is less than 200 ° C., the formation of a film with an adhesive on the fiber and the adhesion to the rubber may be insufficient, whereas at a temperature higher than 255 ° C., it may be on the fiber. This is not preferable because the coating film formed by the treatment agent is deteriorated and the adhesive strength is reduced, and the organic fiber is thermally deteriorated and the strength is reduced. The cord tension during the dry treatment is preferably 0.1 to 2.0 cN / dTex. If it is out of this range, the cord compression rate and the degree of impregnation may be out of the preferred range, and the strength may be reduced.

  According to the present invention, an organic fiber cord having improved fatigue resistance and practically sufficient adhesion to rubber during a rubber vulcanization process or product use can be obtained. Therefore, the rubber product containing the organic fiber cord of the present invention has a practically sufficient adhesive force between the organic fiber cord and the rubber, and can effectively reinforce the rubber product. Useful. Therefore, the rubber product containing the organic fiber cord according to the present invention can withstand severe use for a long time when used as a tire, a belt and a hose.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In the present invention, the methods for measuring and evaluating the physical properties of the organic fiber cord are as follows.

(1) Amount of resin adhesion The weight (A) of the twisted cord per fixed length is measured in advance, and the cord weight (B) of the same length after the adhesive treatment is measured. The resin adhesion amount was calculated according to the calculation formula.
Resin adhesion amount = [(B−A) / A] × 100 (%)

(2) T-adhesive strength (normal conditions and forced deterioration conditions)
It shows the adhesive strength between the treatment cord and rubber. In accordance with JIS L-1017 (2002) adhesive strength-A method, the treatment cord was embedded in unvulcanized rubber, and under pressure, press vulcanization was performed under normal conditions at 150 ° C. for 30 minutes, and forced deterioration conditions were 170 ° C. Press vulcanization was performed for 70 minutes, and after standing to cool, the cord was drawn from the rubber block at a speed of 300 mm / min, and the load required for the drawing was displayed in N / cm.

In addition, the composition of the rubber compound used for the measurement of T-adhesion force is as follows.
Natural rubber (RSS # 1): 80 (parts by weight)
SBR (JSR1501): 20 (parts by weight)
RF carbon black: 50 (parts by weight)
Stearic acid: 2 (parts by weight)
Sulfur: 2 (parts by weight)
Zinc flower: 5 (parts by weight)
2,2′-dithiobenzothiazole: 4 (parts by weight)
Naphthenic acid process oil: 3 (parts by weight).

(3) Fatigue resistance in rubber (normal conditions and forced deterioration conditions)
It was evaluated according to JIS-L1017 (2002) Annex 1 2.2.2 disk fatigue strength (Goodrich method). Two treatment cords are embedded in tire rubber and vulcanized at 150 ° C. for 30 minutes to produce a rubber composite. The test piece was deformed with a compression of 6.3% under normal conditions and an extension of 12.6% for one cycle, and the forced deterioration condition was a deformation with compression of 12.6% and an extension of 12.6% for 1 cycle. After giving for 48 hours at a cycle / minute, the cord was taken out from the rubber, the breaking strength after fatigue was measured, and the retention rate before and after the fatigue test was expressed.

(4) Cord compression rate After measuring the initial cord gauge with a JIS-L1017 (2002) 8.1 cord gauge, the cord gauge after compression was measured by applying a load of 0.15 cN / dTex in the cord cross-sectional direction. The code gauge after compression was divided by the initial code gauge to calculate the code compression rate.

(5) Impregnation degree Using a microtome, the treatment cord was cut in a direction perpendicular to the length direction to obtain a thin piece having a thickness of 20 μm. Then, the cross section of the said process code was observed using the optical microscope which has 200-times magnification. The first polygonal area formed by connecting the outermost monofilaments in the cross section of the processing cord and the monofilaments that are only partially in contact with the RFL adhesive in the cross section of the processing cord. The area of the second polygon formed by each was measured. Subsequently, the degree of impregnation of the adhesive into the twisted yarn was calculated using the following formula:
P = [(A1-A2) / A1] × 100 (%)
Here, P is the degree of impregnation of the RFL adhesive into the twisted yarn, and A1 is formed by connecting the outermost monofilaments in the cross section of the processing cord perpendicular to the length direction of the processing cord. A2 is the area of the second polygon formed by linking the monofilaments that only partially contact the RFL adhesive in the cross section of the processing cord.

(Examples 1-6), (Comparative Examples 1-6)
As a smectite, a silicate compound was dispersed in water to prepare a 2 w% aqueous dispersion having a thixotropy index of 5. A polyepoxide compound, a rubber latex, and an aqueous dispersion of a silicate compound were mixed at a ratio shown in Table 1 as a solid content to prepare a primer treatment agent having a solid content concentration shown in Table 1. Further, an RFL adhesive having a solid content concentration shown in Table 1 was prepared by mixing resorcin / formalin initial condensate (RF) and rubber latex at a ratio of 1/5 in solid content. The preparation method of the RFL adhesive is as follows. The initial condensate (RF) of resorcin (R) and formalin (F) has an (R / F) molar ratio of 1/2 and a solid content concentration of 20% by weight, and is aged for 6 hours under a commonly used alkali catalyst. The resorcin / formalin precondensate was used. Thereafter, rubber latex was added to a solid content concentration of 20%, and after aging for 24 hours, ion exchange water was added to prepare an RFL adhesive having a target solid content concentration.
Polyepoxide compound: EX-421 (manufactured by Nagase ChemteX)
Silicate compound: “Lucentite” SWF (manufactured by Corp Chemical)
Rubber latex: 2518FS (made by Nippon Zeon)

  Two polyester multifilament yarns of 1100 dTex (“Tetron” 1100-240-705M manufactured by Toray Industries, Inc.) were twisted at the number of twists shown in Table 1 to obtain untreated cords.

  The untreated code is immersed in the primer treatment agent using a compute treater (CA Ritzler), dried at 120 ° C. for 2 minutes (dry treatment), and subsequently heat treated at 240 ° C. for 1 minute. (Hot treatment) was performed. Table 1 shows the roller pressure, cord tension during dipping, and cord tension during dry treatment. Subsequently, after being immersed in an RFL adhesive, it is dried at 120 ° C. for 2 minutes (dry treatment), subsequently subjected to heat treatment at 240 ° C. for 0.5 minutes (hot treatment), and further heat treatment at 240 ° C. for 0.5 minutes (hot treatment). Normalization processing was performed. Table 1 shows the roller pressure, cord tension during dipping, and cord tension during dry treatment.

  The obtained treated cord was measured for resin adhesion, T-adhesive strength, fatigue resistance in rubber, cord compression rate, and impregnation degree. The results are shown in Table 1.

  As in the results of Table 1, in Examples 1 to 6 according to the present invention, the fatigue resistance in rubber is better and the adhesion is better than conventional organic fibers (Comparative Examples 1 to 6). It can be seen that it is.

Claims (4)

  It has a lower twist and an upper twist, the twist coefficient of the lower twist is 1000 to 2500, the twist coefficient of the upper twist is 1500 to 3600, and the various twist cords are coated with an adhesive containing resorcin, formalin rubber latex (RFL). An organic fiber cord having a cord compression ratio of 83 to 97% and an RFL impregnation degree of 10 to 50% inside the cord.   The organic fiber cord according to claim 1, wherein the organic fiber includes at least one selected from polyethylene terephthalate, nylon 66, and aramid.   The organic fiber cord according to claim 1 or 2, which is used for rubber reinforcement.   The rubber product containing the organic fiber cord in any one of Claims 1-3.