JP6588259B2 - Polyamide fiber for transmission belt, and cord, woven fabric, and transmission belt using the same - Google Patents

Description

  The present invention relates to a polyamide fiber for a transmission belt excellent in rubber adhesion and durability at high temperatures, and a cord, a fabric, and a transmission belt using the same.

A power transmission belt is a belt that plays a role of power transmission, and is currently used in various applications from automobiles to general industrial equipment. The power transmission mechanism can be roughly divided into friction transmission and synchronous transmission. Examples of the former include a V belt, a V-ribbed belt, and a flat belt, and examples of the latter include a toothed belt.
Especially in automotive applications, the engine room has become increasingly hot due to the reduction in weight and size of the vehicle, which has led to improved fuel efficiency, and the higher performance of the engine. However, there is an increasing demand for heat resistance.
Currently, nylon 6 and nylon 66 are used for the core wire and tooth cloth of the transmission belt. However, these fibers are excellent in rubber adhesion and fatigue resistance, but have problems in terms of heat resistance when used at high temperatures.

  On the other hand, a technique using an aramid fiber has been disclosed for the purpose of improving heat resistance. However, although the aramid fiber has high heat resistance of the fiber itself, it has a drawback of poor adhesion to rubber. Therefore, as described in Patent Documents 1 and 2 below, a composite yarn with nylon 66 that is excellent in adhesive improvement and rubber adhesion has been proposed, but it is not sufficient. In addition, since the aramid fiber has a further lowered adhesive property with rubber at high temperature, there is a problem that the performance as expected as the heat resistance of the transmission belt cannot be obtained.

JP 2006-207600 A JP-A-7-217704

  In view of the above-described state of the art, the problem to be solved by the present invention is to provide a polyamide fiber for a transmission belt excellent in rubber adhesion and durability at high temperature, and a cord, a woven fabric, and a transmission belt using the same. That is.

  As a result of intensive studies and repeated experiments to solve the above-mentioned problems, the present inventors have used a multifilament fiber made of a novel high-melting-point polyamide resin for a transmission belt cord and / or woven fabric, thereby achieving good rubber adhesion. The present inventors have found that a transmission belt cord, a woven fabric, and a transmission belt that are excellent in durability and durability at high temperatures can be obtained, and have completed the present invention.

That is, the present invention is as follows.
[1] A polycondensate of a dicarboxylic acid containing an alicyclic dicarboxylic acid and a diamine, wherein the ratio of the alicyclic dicarboxylic acid to the dicarboxylic acid is 50 mol% or more, and storage elasticity at 120 ° C The ratio of the modulus E ′ (120 ° C.) and the storage elastic modulus E ′ (25 ° C.) at 25 ° C., and the value of E ′ (120 ° C.) / E ′ (25 ° C.) is 0.6 or more and 0.9 or less. A polyamide fiber for power transmission belts.
[2] The polyamide fiber for a transmission belt according to the above [1], wherein the heat resistant adhesion retention with rubber after heat treatment at 180 ° C. for 5 hours is 80% or more.
[3] The polyamide fiber for a transmission belt according to [1] or [2], wherein a rubber adhesion property measured according to JIS L1017: 2002 Annex 1 (3.1 T test) is 1000 N / cm ² or more. .
[ 4 ] The polyamide fiber for a transmission belt according to any one of [1] to [ 3 ], wherein Δn of the polyamide fiber is 0.04 or more.
[ 5 ] The polyamide fiber for a transmission belt according to any one of [1] to [ 4 ], wherein the polyamide fiber contains 1 ppm to 500 ppm of copper element.
[ 6 ] The polyamide fiber for a transmission belt according to any one of [1] to [ 5 ], wherein the tensile strength is 4.0 cN / dtex or more.
[ 7 ] The polyamide fiber for a transmission belt according to any one of [1] to [ 6 ], wherein the heat resistant strength retention after heat treatment for 12 hours in an air environment of 180 ° C. is 70% or more.
[ 8 ] The polyamide fiber for a transmission belt according to any one of [1] to [ 7 ], wherein the single yarn fineness is 0.5 dtex or more and 10 dtex or less.
[ 9 ] A transmission belt cord obtained by treating the polyamide fiber for a transmission belt according to any one of [1] to [ 8 ] with a resorcin-formalin-latex resin.
[ 10 ] The transmission belt cord according to [ 9 ], wherein the rubber adhesion property measured according to JIS L1017: 2002 Annex 1 (3.1 T test) is 1000 N / cm ² or more.
[ 11 ] A transmission belt using the transmission belt cord according to [ 9 ] or [ 10 ] as a core of the belt.
[ 12 ] A woven fabric for a transmission rubber belt, wherein the polyamide fiber for a transmission belt according to any one of [1] to [ 8 ] is used for any one of the weaving yarns.
[ 13 ] A transmission belt using the transmission belt fabric described in [ 12 ] as a belt tooth cloth.

  The present invention uses a multifilament fiber made of a novel high-melting-point polyamide resin for a transmission belt cord and / or woven fabric, so that the transmission belt cord, woven fabric, and excellent rubber adhesion and durability at high temperatures are obtained. A transmission belt can be provided.

Hereinafter, embodiments for carrying out the present invention will be described in detail. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist.
The polyamide fiber for a transmission belt according to this embodiment has a storage elastic modulus E ′ (120 ° C.) at 120 ° C. and a storage elastic modulus E ′ (25 ° C.) at 25 ° C., that is, E ′ (120 ° C.) / It has a dynamic viscoelastic property that E ′ (25 ° C.) is 0.6 or more and 0.9 or less, and such a ratio is preferably 0.7 or more and 0.9 or less.

  In general, when the rigidity is lowered at a high temperature and the belt is loosened, the slip increases between the belt and the pulley, and the durability of the belt deteriorates. In addition, when an auto tensioner is provided, slip is suppressed, but the amount of belt wound around the auto tensioner is increased to suppress loosening, the bending becomes large, and the life is shortened. Therefore, if the cord of the polyamide fiber of this embodiment having E ′ (120 ° C.) / E ′ (25 ° C.) of 0.6 or more is used for the core wire, the rigidity at high temperature is improved, and the belt Looseness is suppressed, and as a result, durability at high temperatures is improved. On the other hand, when E ′ (120 ° C.) / E ′ (25 ° C.) is larger than 0.9, the molecular chain is essentially very rigid, and the affinity with the adhesive is poor. Since adhesiveness falls, in this embodiment, E '(120 degreeC) / E' (25 degreeC) is 0.9 or less.

  Further, when the polyamide fiber fabric of this embodiment having E ′ (120 ° C.) / E ′ (25 ° C.) of 0.6 or more is used for the tooth cloth, the rigidity of the tooth cloth is maintained even at a high temperature. Further, it is possible to suppress the bending of the rubber teeth during the belt running. As a result, it is possible to suppress heat generation of the rubber teeth, reduce tooth cracks and chipping, and improve the durability of the toothed belt at high temperatures. Even when used for a tooth cloth, a fiber having an E ′ (120 ° C.) / E ′ (25 ° C.) larger than 0.9 has a problem of adhesion, so that E ′ (120 ° C.) / E ′ ( 25 ° C.) is 0.9 or less.

The rubber adhesive property (N / cm ² ) of the polyamide fiber for a transmission belt of this embodiment is preferably 1000 N / cm ² or more, more preferably 1050 or more, and further preferably 1100 or more. When the rubber adhesion property is low, peeling occurs at the rubber-cord interface or the rubber-woven fabric interface constituting the transmission belt, leading to a reduction in the service life. In this embodiment, by using a polyamide fiber for a transmission belt having a rubber adhesion property of 1000 N / cm ² or more, peeling at the interface between rubber and cord or between the rubber and fabric can be reduced. Greatly contributes to durability.

  The heat-resistant adhesive retention of the power transmission belt fiber of this embodiment is preferably 80% or more, more preferably 85% or more, and further preferably 90% or more. Even if the rubber adhesive property at normal temperature is good, the adhesive property often deteriorates under high temperature exposure. Therefore, the heat resistant adhesive retention is particularly important for the durability of the belt at high temperature. When the heat-resistant adhesion retention rate is 80% or more, it is possible to reduce the peeling of the rubber and cord or the rubber and the fabric constituting the transmission belt when the belt is run in a high temperature environment, greatly contributing to the life of the belt. .

  The melting point of the polyamide fiber for a transmission belt of this embodiment is preferably 270 ° C. or higher. The higher the melting point of the fiber, the higher the durability when the transmission belt is used at a high temperature. The melting point is more preferably 275 ° C. or higher, and further preferably 280 ° C. or higher. On the other hand, the melting point is preferably 350 ° C. or less from the viewpoint that uniform multifilament fibers can be easily obtained by melt spinning.

  The heat resistant strength retention after heat treatment of the polyamide fiber for a transmission belt of this embodiment for 12 hours in an air environment at 180 ° C. is preferably 70% or more, more preferably 75% or more, and still more preferably 80% or more. . When the heat resistant strength retention is 70% or more, the fiber breakage under high temperature use is reduced, and the durability of the belt is improved.

The peak temperature of the loss tangent (tan δ) determined by the dynamic viscoelasticity measurement of the polyamide fiber for a transmission belt of the present embodiment is preferably 150 ° C. or higher and 200 ° C. or lower. When the peak temperature of tan δ is 150 ° C. or higher, the movement of the molecular chain in the amorphous part or the amorphous region is suppressed, and the fatigue resistance at high temperatures is improved.
Further, the value of tan δ at the peak temperature is preferably 0.3 or less. By stretching the fiber and reducing tan δ, the molecular chain is difficult to move and the rigidity at high temperature is maintained. In addition, the structure of the molecular chain does not change due to repeated stretching motion, and therefore the fiber has excellent fatigue resistance. The value of tan δ is 0.01 or more in the normal stretching.

The polyamide fiber for a transmission belt according to this embodiment is preferably an alicyclic polyamide fiber made of a polyamide obtained by polycondensation of a dicarboxylic acid and a diamine containing 50 mol% or more of the alicyclic dicarboxylic acid to the dicarboxylic acid. With such a composition, a high melting point of the fiber is achieved, heat resistance is improved, and the amount of change in storage elastic modulus at room temperature and high temperature is small, and transmission with better dimensional stability than nylon 6 or nylon 66 fiber. A belt can be obtained. In addition, such an alicyclic polyamide fiber has an amide bond as an aliphatic polyamide, and therefore has excellent adhesion to rubber. Furthermore, a yarn having a flexible polymer structure and a high elongation at break can be obtained as compared with a polyamide containing a structural unit derived from an aromatic group as a general heat-resistant polyamide.
Δn is birefringence, and the degree of fiber orientation can be evaluated. By applying an appropriate drawing process, the fibers are uniaxially oriented and Δn increases. Δn is preferably 0.04 or more. When Δn is 0.04 or more, the storage elastic modulus, which is an index of rigidity, is increased, and the decrease in storage elastic modulus at high temperatures can be moderated, contributing to dimensional stability and rigidity retention.

Polyamide means a polymer having an amide (—NHCO—) bond in the main chain. Further, “the ratio of the alicyclic dicarboxylic acid to the dicarboxylic acid is 50 mol% or more” means “the ratio of the structural unit derived from the alicyclic dicarboxylic acid to the structural unit derived from the raw material monomer component is 25 mol% or more”. To do.
The fineness of the polyamide fiber for a transmission belt of the present invention is preferably 20 dtex or more and 3000 dtex or less from the viewpoint of spinnability.

  When the polyamide fiber for a transmission belt of the present embodiment is used as a core wire of the transmission belt, the (total) fineness is preferably 100 dtex or more and 10000 dtex or less. When the fineness is 100 dtex or more, the mechanical strength required as the core can be obtained, and from the viewpoint of lightness, it is preferably 10,000 dtex or less. In order to achieve such fineness, several yarns may be combined or twisted.

  When the polyamide fiber for a transmission belt according to this embodiment is used as a tooth cloth for a transmission belt, the (total) fineness is preferably 10 dtex or more and 1500 dtex or less. The mechanical strength required when weaving a tooth cloth with a fineness of 10 dtex or more can be obtained, and 1500 dtex or less is preferable from the viewpoint of the flexibility of the tooth cloth.

  The single yarn fineness of the polyamide fiber for a transmission belt of the present embodiment is preferably 0.5 dtex or more and 10.0 dtex or less from the viewpoint of bending strength and fatigue resistance. If the single yarn fineness is 0.5 dtex or more, it is difficult to cause a problem in the productivity of the yarn. On the other hand, if the single yarn fineness is 10.0 dtex or less, highly flexible fibers can be obtained, and bending strength and resistance Fatigue is improved.

  The number of single yarns of the polyamide fiber for a transmission belt of this embodiment is preferably 10 filaments or more and 500 filaments or less. When the number of single yarns is 10 filaments or more, the specific surface area is increased and the external stress can be flexibly dealt with, thereby improving rubber adhesion and fatigue resistance. On the other hand, when the number of filaments is 500 filaments or less, it is possible to avoid fusion of single yarns during melt spinning.

  The strength of the polyamide fiber constituting the cord and / or woven fabric of the present embodiment is preferably 4.0 cN / dtex or more, more preferably 5.0 cN / dtex or more, even more preferably, when used as a transmission belt. Is 6.0 cN / dtex or more.

Hereinafter, the polymer composition of the alicyclic polyamide multifilament fiber which is the yarn constituting the cord and / or the fabric of the present embodiment will be described.
[Dicarboxylic acid]
The polyamide multifilament fiber of this embodiment is a polyamide multifilament fiber made of a polycondensate of a dicarboxylic acid containing an alicyclic dicarboxylic acid and a diamine, and the ratio of the alicyclic dicarboxylic acid to the dicarboxylic acid is at least 50 mol. % Or more, preferably 60 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, and most preferably 100 mol%. By including at least 50 mol% of structural units derived from alicyclic dicarboxylic acids, polyamide multifilaments with improved heat resistance due to higher melting point, retention of storage elastic modulus (E ') at high temperature, fiber strength and spinnability Fiber can be obtained.

The alicyclic dicarboxylic acid is not limited to the following. For example, the alicyclic dicarboxylic acid having 3 to 10 carbon atoms in the alicyclic structure, preferably 5 to 10 carbon atoms in the alicyclic structure. The alicyclic dicarboxylic acid which is is mentioned. Specific examples include, but are not limited to, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, and the like.
The alicyclic dicarboxylic acid may be unsubstituted or may have a substituent. Examples of the substituent include, but are not limited to, for example, 1 to 4 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and tert-butyl group. And the like.
As the alicyclic dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid is preferable from the viewpoints of heat resistance, dimensional stability, strength and the like of the polyamide multifilament fiber.
One type of alicyclic dicarboxylic acid may be used alone, or two or more types may be used in combination.

  An alicyclic dicarboxylic acid has a trans isomer and a cis geometric isomer. For example, 1,4-cyclohexanedicarboxylic acid as a raw material monomer may use either a trans isomer or a cis isomer, or may be used as a mixture in various ratios of a trans isomer and a cis isomer. 1,4-Cyclohexanedicarboxylic acid is isomerized at a high temperature to have a certain ratio, and the cis isomer has higher water solubility in the equivalent salt with diamine than the trans isomer. The body ratio, that is, the molar ratio of trans isomer / cis isomer is preferably 50/50 to 0/100, more preferably 40/60 to 10/90, and still more preferably 35/65 to 15/85. It is. When the trans isomer ratio is within the above range, polyamide not only has excellent properties such as high melting point, toughness, and strength, but also has a high glass transition temperature (point) and usually has a property that is contrary to heat resistance. A certain fluidity and high crystallinity can be satisfied at the same time. The molar ratio of the trans form / cis form of 1,4-cyclohexanedicarboxylic acid can be determined by liquid chromatography (HPLC) or nuclear magnetic resonance spectroscopy (NMR).

Examples of dicarboxylic acids other than alicyclic dicarboxylic acids include, but are not limited to, for example, malonic acid, dimethylmalonic acid, succinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylglutaric acid, 2,2-diethylsuccinic acid, 2,3-diethylglutaric acid, glutaric acid, 2,2-dimethylglutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, suberic acid, azelaic acid, sebacine Examples thereof include linear or branched aliphatic dicarboxylic acids having 3 to 20 carbon atoms such as acid, dodecanedioic acid, tetradecanedioic acid, hexadecanedioic acid, octadecanedioic acid, eicosanedioic acid, and diglycolic acid.
Moreover, you may add aromatic dicarboxylic acid to the said dicarboxylic acid in the range which does not inhibit the fluidity | liquidity of the polyamide whose ratio of aromatic dicarboxylic acid with respect to dicarboxylic acid is 0 mol% or more and 10 mol% or less. Examples of the aromatic dicarboxylic acid include, but are not limited to, for example, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium Examples thereof include aromatic dicarboxylic acids having 8 to 20 carbon atoms which are unsubstituted or substituted with various substituents such as sulfoisophthalic acid.
As long as the ratio of the alicyclic dicarboxylic acid to the dicarboxylic acid is at least 50 mol% or more, a dicarboxylic acid other than those described above may be included unless the desired effects are impaired.

[Diamine]
The polyamide multifilament fiber of this embodiment contains 1,10-decamethylenediamine as a diamine component from the viewpoint of spinning stability, heat resistance, and low water absorption, and the ratio of 1,10-decamethylenediamine to diamine is It is preferable that it is 20 mol% or more. The ratio of 1,10-decamethylenediamine to diamine is preferably at least 20 mol% or more, more preferably 30 mol% or more and 80 mol% or less, still more preferably 40 mol% or more and 75 mol% or less, and even more preferably 45. The mol% is 70 mol% or more.
When the melting point is too high due to the composition, the polyamide is thermally decomposed at the time of melting, resulting in a decrease in molecular weight and strength, coloring, and mixing of decomposition gas, resulting in poor spinnability. However, by including 1,10-decamethylenediamine in an amount of 20 mol% to 80 mol%, the melting point suitable for melt spinning can be suppressed while maintaining a high Tg. Moreover, since the polyamide containing 1,10-decamethylenediamine has high thermal stability at the time of melting, a multifilament fiber having excellent spinning stability and good uniformity can be obtained. Moreover, the thread | yarn which is excellent in the dimensional stability at the time of water absorption can be obtained because the amide group density | concentration in polyamide falls. Furthermore, 1,10-decamethylenediamine is also preferable from the viewpoint that it is a biomass-derived raw material.

The diamine other than 1,10-decamethylenediamine is not particularly limited, and may be an unsubstituted linear aliphatic diamine, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl. A branched aliphatic diamine having a substituent such as an alkyl group having 1 to 4 carbon atoms such as a tert-butyl group or an alicyclic diamine may be used.
Examples of diamines other than 1,10-decamethylenediamine include, but are not limited to, ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, Non-methylene diamine, decamethylene diamine, undecamethylene diamine, dodecamethylene diamine, tridecamethylene diamine and other linear aliphatic diamines, 2-methylpentamethylene diamine, 2,2,4-trimethylhexamethylene diamine, 2-methyl Examples include octamethylenediamine, 2,4-dimethyloctamethylenediamine, 1,4-cyclohexanediamine, 1,3-cyclohexanediamine, 1,3-cyclopentanediamine, and the like.

Moreover, you may add aromatic diamine to diamine in the range which does not inhibit the fluidity | liquidity of the polyamide whose ratio of aromatic diamine with respect to diamine is 0 mol% or more and 10 mol% or less. The aromatic diamine is a diamine containing an aromatic, and is not limited to the following, and examples thereof include metaxylylenediamine, orthoxylylenediamine, paraxylylenediamine, and the like.
As the diamine other than 1,10-decamethylenediamine, a diamine having 5 to 6 carbon atoms and a ratio of the diamine having 5 to 6 carbon atoms being 20 mol% or more is more preferable. By copolymerizing a diamine having 5 to 6 carbon atoms in addition to 1,10-decamethylenediamine, a polymer having high crystallinity can be obtained while maintaining an appropriate melting point suitable for spinning. Examples of the diamine having 5 to 6 carbon atoms include pentamethylenediamine, hexamethylenediamine, 2-methylpentamethylenediamine, 2,5-dimethylhexanediamine, and 2,2,4-trimethylhexamethylenediamine.

  Among the diamines having 5 to 6 carbon atoms, 2-methylpentamethylenediamine is preferable from the viewpoint of spinnability, fluidity, and strength. If the ratio of 2-methylpentamethylenediamine is too high, 2-methylpentamethylenediamine is self-cyclized and decomposes when melted, causing a decrease in molecular weight, resulting in poor spinnability and strength. The ratio of 2-methylpentamethylenediamine in the diamine needs to be set in a range where decomposition is not caused at the time of melting while ensuring fluidity, preferably 20 mol% or more and 70 mol% or less, more preferably It is 20 mol% or more and 60 mol% or less, More preferably, it is 20 mol% or more and 55 mol% or less.

  Of the diamines having 5 to 6 carbon atoms, hexamethylene diamine is preferable from the viewpoint of heat resistance of the polyamide multifilament fiber. If the ratio of hexamethylenediamine is too high, the melting point becomes too high and spinning becomes difficult, so the ratio of hexamethylenediamine in the diamine is preferably 20 mol% or more and 60 mol% or less, more preferably 20 mol. % To 50 mol%, more preferably 20 mol% to 45 mol%.

  The addition amount of the dicarboxylic acid and the addition amount of the diamine are preferably around the same molar amount in order to increase the molecular weight. The amount of diamine escaped from the reaction system during the polymerization reaction is also considered in terms of molar ratio, and the total amount of diamine is 0.90 to 1.20 compared to the total amount of 1.00 of dicarboxylic acid. Preferably, it is 0.95 to 1.10, more preferably 0.98 to 1.05.

[Lactam and / or aminocarboxylic acid]
The polyamide multifilament fiber of the present embodiment may contain a component derived from lactam and / or aminocarboxylic acid as long as desired effects are not impaired.
Examples of the lactam include, but are not limited to, butyrolactam, pivalolactam, ε-caprolactam, caprilactam, enantolactam, undecanolactam, laurolactam (dodecanolactam), and the like.

The aminocarboxylic acid is not limited to the following, but is preferably, for example, a linear or branched saturated aliphatic carboxylic acid having 4 to 14 carbon atoms substituted with an amino group at the ω position. -Aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and the like can be mentioned, and examples of the aminocarboxylic acid include paraaminomethylbenzoic acid.
The component ratio derived from the lactam and / or aminocarboxylic acid is not particularly limited, but the ratio derived from the lactam and / or aminocarboxylic acid component to the structural unit derived from the raw material monomer component is 0 mol% or more and 20 mol. % Or less, more preferably 2 mol% or more and 15 mol% or less. When the ratio derived from the lactam and / or aminocarboxylic acid component is 0 mol% or more and 20 mol% or less, a polyamide multifilament fiber excellent in heat resistance, spinnability, and strength can be obtained.

[Terminal blocking agent]
When polymerizing a polyamide from a dicarboxylic acid and a diamine, a known end-capping agent can be further added to adjust the molecular weight. Examples of the end-capping agent include monocarboxylic acids, monoamines, acid anhydrides such as phthalic anhydride, monoisocyanates, monoacid halides, monoesters, monoalcohols, and the like, from the viewpoint of thermal stability. Monocarboxylic acid and monoamine are preferable. One type of end capping agent may be used, or two or more types may be used in combination.
The monocarboxylic acid that can be used as the end-capping agent is not particularly limited as long as it has reactivity with an amino group. For example, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid , Aliphatic monocarboxylic acids such as caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid and isobutyric acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, and aromatic monocarboxylic acids such as α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid.

One kind of monocarboxylic acid as a terminal blocking agent may be used, or two or more kinds may be used in combination.
The monoamine that can be used as the end-capping agent is not particularly limited as long as it has reactivity with a carboxyl group. For example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, Aliphatic monoamines such as decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine, and naphthylamine; It is done. Monoamine as a terminal blocking agent may be used alone or in combination of two or more.

[Additive]
For thermal stability in a high temperature and high humidity environment, it is preferable to add a copper compound so that the copper concentration is 1 ppm or more and 500 ppm or less with respect to the polyamide fiber, and more preferably 30 to 500 ppm or less. is there. By doing so, even if the transmission belt of this embodiment is left in a high temperature and high humidity environment for a long time or exposed to an environment containing a lot of ozone for a long period of time, the reduction in mechanical performance is extremely effective. To be suppressed. When the copper content is less than 30 ppm, the heat resistant strength retention ratio decreases, and when the added amount exceeds 500 ppm, the strength decreases.

The type of the copper compound is not particularly limited, and for example, an organic copper salt such as copper acetate, or a copper halide such as cuprous chloride or cupric chloride can be preferably used. The copper compound is more preferably used in combination with a metal halide compound. Examples of the metal halogen compound include potassium iodide, potassium bromide, potassium chloride and the like. Preferred combinations in this embodiment are cuprous iodide and potassium iodide, and copper acetate and potassium iodide. The copper content in the polyamide can be measured by high frequency inductively coupled plasma (ICP) emission analysis or colorimetric method.
Although not limited to the following, as stabilizers, organic antioxidants such as hindered phenol antioxidants, sulfur antioxidants, phosphorus antioxidants, heat stabilizers, hindered amines, benzophenones, imidazoles, etc. A light stabilizer, an ultraviolet absorber, or the like may be added. The addition amount should just select an appropriate quantity, but 1-1000 ppm can be added with respect to polyamide. These additives may be used alone or in combination of several kinds.

[Degree of polymerization]
The molecular weight distribution of the polyamide multifilament fiber can be evaluated by Mw (weight average molecular weight) / Mn (number average molecular weight). Mw / Mn of the polyamide multifilament fiber is preferably 4.0 or less, more preferably 1.5 to 3.8, and still more preferably 1.5 to 3.5 from the viewpoints of stretchability and fiber strength. It is. The lower limit of Mw / Mn is 1.0.
From the viewpoints of mechanical properties such as high elongation and spinnability, the polyamide multifilament fiber has a sulfuric acid relative viscosity (ηr) of 1.5% or more at a concentration of 1% in 98% sulfuric acid measured in accordance with JIS-K6810 at 25 ° C. 4.0 or less, preferably 1.7 or more and 3.5 or less, more preferably 1.8 or more and 3.3 or less. If ηr is 1.5 or less, fibers having sufficient strength cannot be obtained for industrial materials, and fibers having ηr of 4.0 or more are difficult to spin because of poor polymer fluidity. I can't.

[Production method of polyamide]
Examples of the method for producing the polyamide include various methods as exemplified below:
(1) A method in which an aqueous solution or a suspension of water of a dicarboxylic acid / diamine salt or a mixture thereof is heated and polymerized while maintaining a molten state (hereinafter also abbreviated as “hot melt polymerization method”).
(2) A method of increasing the degree of polymerization while maintaining the solid state of the polyamide obtained by the hot melt polymerization method at a temperature below the melting point (hereinafter also abbreviated as “hot melt polymerization / solid phase polymerization method”).
(3) A method in which an aqueous solution or a suspension of water of a diamine / dicarboxylate salt or a mixture thereof is heated, and the precipitated prepolymer is melted again with an extruder such as a kneader to increase the degree of polymerization (hereinafter, “ Also abbreviated as “prepolymer / extrusion polymerization method”).
(4) A method in which an aqueous solution or a suspension of water of a diamine / dicarboxylate or a mixture thereof is heated, and the degree of polymerization is increased while maintaining the solid state at a temperature below the melting point of the polyamide. (Also abbreviated as “prepolymer / solid phase polymerization method”).
(5) A method of polymerizing a diamine dicarboxylate or a mixture thereof while maintaining a solid state (hereinafter, also abbreviated as “solid phase polymerization method”).
(6) A “solution method” in which polymerization is performed using a dicarboxylic acid halide component equivalent to dicarboxylic acid and a diamine component.

  In the polyamide production method, from the viewpoint of the fluidity of the polyamide, it is preferable to carry out the polymerization while maintaining the trans isomer ratio of the alicyclic dicarboxylic acid at 85% or less, and particularly by maintaining at 80% or less, Polyamide having excellent color tone and tensile elongation and high melting point can be obtained. In the polyamide production method, it is necessary to increase the heating temperature and / or lengthen the heating time in order to increase the melting point of the polyamide by increasing the degree of polymerization. There is a case where the tensile elongation is lowered due to coloring of the polyamide or thermal deterioration. In addition, the rate at which the molecular weight increases may decrease significantly. Since it is possible to prevent a decrease in tensile elongation due to polyamide coloring or thermal deterioration, it is preferable to perform polymerization while maintaining the trans isomer ratio at 80% or less.

As a method for producing polyamide, since it is easy to maintain the trans isomer ratio at 85% or less, and because the color tone of the obtained polyamide is excellent, (1) hot melt polymerization method or (2) heat It is preferable to produce polyamide by a melt polymerization / solid phase polymerization method.
In the method for producing polyamide, the polymerization form may be a batch type or a continuous type. The polymerization apparatus is not particularly limited, and examples thereof include known apparatuses such as an autoclave reactor, a tumbler reactor, an extruder reactor such as a kneader.

As a method for producing polyamide, polyamide can be produced by a batch-type hot melt polymerization method described below.
As a batch type hot melt polymerization method, for example, water is used as a solvent, and a polyamide component (dicarboxylic acid, diamine, and, if necessary, lactam and / or aminocarboxylic acid) is contained in about 40 to 60% by mass. The solution is concentrated to about 65 to 90% by mass in a concentration tank operated at a temperature of 110 to 180 ° C. and a pressure of about 0.035 to 0.6 MPa (gauge pressure) to obtain a concentrated solution. The concentrated solution is then transferred to an autoclave and heating is continued until the pressure in the container is about 1.5-5.0 MPa (gauge pressure). Thereafter, the pressure is maintained at about 1.5 to 5.0 MPa (gauge pressure) while draining water and / or gas components, and when the temperature reaches about 250 to 350 ° C., the pressure is reduced to atmospheric pressure (gauge pressure is , 0 MPa). By reducing the pressure to atmospheric pressure and then reducing the pressure as necessary, by-product water can be effectively removed. Thereafter, pressurization is performed with an inert gas such as nitrogen to extrude the polyamide melt as a strand. The strand is cooled and cut to obtain pellets.

As a method for producing the polyamide, the polyamide can also be produced by a continuous hot melt polymerization method described below.
As the continuous hot melt polymerization method, for example, a solution of about 40 to 60% by mass containing water and a polyamide component as a solvent is preheated to about 40 to 100 ° C. in a container of a preliminary apparatus, and then a concentration tank / Concentrated to about 70-90% at a pressure of about 0.1-0.5 MPa (gauge pressure) and a temperature of about 200-270 ° C. to obtain a concentrated solution. The concentrated solution is discharged into a flasher maintained at a temperature of about 200 to 350 ° C., and then the pressure is reduced to atmospheric pressure (gauge pressure is 0 MPa). After reducing the pressure to atmospheric pressure, reduce the pressure as necessary. The polyamide melt is then extruded into strands, cooled and cut into pellets.

[Polyamide multifilament fiber]
The polyamide multifilament fiber of the present embodiment is obtained by fiberizing the above-described polyamide by a predetermined method. Since this polyamide is an alicyclic polyamide, its fluidity and spinnability are superior to aromatic polyamides, but inferior to general aliphatic polyamides such as nylon 66. Moreover, since Tm is also high, deterioration of the polymer due to heat and flow characteristics become very severe. In the present embodiment, fibers excellent in strength, spinning stability, and uniformity can be obtained by the following production method.

Various methods can be used as a method for producing the polyamide multifilament fiber, but usually, melt spinning is used, and it is preferable to use a screw-type melt extruder. The spinning temperature (melting temperature) of the polyamide is preferably 300 ° C. or higher and 360 ° C. or lower. If it is 300 degreeC or more, mixing of the undissolved substance by heat shortage can be suppressed. On the other hand, if it is 360 degrees C or less, the thermal decomposition of a polymer and generation | occurrence | production of a decomposition gas will be reduced significantly and spinnability will improve.
After the thermal melting, it is passed through a spinning pack incorporating a metal nonwoven fabric filter having pores with a pore diameter of about 10 to 100 μm, and discharged through a nozzle hole nozzle called a spinning nozzle. In order to obtain a multifilament, the nozzle in this case preferably has 30 or more holes. Moreover, in order to ensure spinnability, the hole diameter is preferably 0.10 mm to 0.50 mm. Furthermore, L / D, which is the ratio of the nozzle length (L) to the diameter (D), is preferably in the range of 1.0 to 4.0.

Since a multifilament spinneret requires a large number of pores, the surface area of the spinneret is larger than that of a monofilament, and temperature spots on the spinneret surface tend to occur. In particular, the polyamide multifilament fiber of the present embodiment has a high Tm and has a large influence on the flow characteristics due to temperature. Therefore, it is difficult to obtain a uniform fiber when temperature spots occur. Therefore, it is particularly important to reduce temperature spots on the spinneret surface and to equalize the polymer temperature during discharge. In order to improve the uniformity of the spinneret surface temperature, it is preferable to install a spinneret heater. In particular, since the outer surface of the spinneret is cooled strongly by the accompanying flow of the yarn, the spinner heater is preferably attached directly to the spinneret so as to surround the outer side of the spinneret.
The temperature of the spinneret is heated from Tm to Tm + 60 ° C with a spinner heater, and the temperature difference between the center and outer periphery of the spinneret is within 3 ° C. A fiber having excellent properties can be obtained. When the spinneret surface temperature is equal to or higher than Tm, uniform fibers can be obtained without causing discharge spots due to insufficient heat. Thermal deterioration can be reduced when the spinneret surface temperature is lower than Tm + 60 ° C.

  It is preferable to provide a heating zone with a heating cylinder or the like on the yarn immediately after being discharged. The heating cylinder is a heater that surrounds the yarn. Since the polyamide multifilament fiber of the present embodiment has a high Tm, the solidification rate immediately after spinning is high, the spinnability is lowered, and the cutting yarns just below the spinneret frequently occur, making spinning difficult. Therefore, by installing a heating cylinder and making the atmospheric temperature just below the spinning nozzle high and uniform, the solidification speed of the molten polymer and solidification spots between single yarns can be suppressed, and the spinnability is greatly improved. In addition, since the polyamide multifilament fiber of this embodiment has a high Tg, it is easily oriented due to the influence of the spinning draft, leading to a decrease in stretchability. However, by installing a heating cylinder, non-uniform orientation in the spinning draft is achieved. Relaxes and improves stretchability and strength. Since the yarn is cooled from the single yarn on the outer periphery due to the influence of the accompanying flow, the heating cylinder is preferably a cylindrical heater that surrounds the yarn from the outside.

Further, in order to ensure the spinnability immediately after discharge and to relax the orientation, the distance of the heating zone is necessary, and the length of the heating cylinder is preferably 10 to 300 mm, for example. Furthermore, the temperature of the heating cylinder is preferably 100 ° C. or higher and 200 ° C. or lower. When the temperature is less than 100 ° C., the discharged molten polymer is immediately solidified, and the spinnability and orientation relaxation are reduced. On the other hand, when the temperature is higher than 200 ° C., thermal deterioration occurs, resulting in a decrease in strength and a deterioration in color tone.
The yarn that has passed through the heating zone is rapidly cooled and solidified by applying cold air. The cold air speed at this time is preferably in the range of 0.2 to 2.0 m / min. If it is slower than 0.2 m / min, cooling is insufficient. When the speed is faster than 2.0 m / min, the yarn sway increases, the single yarns come into contact with each other, and the single yarns are brought into close contact with each other, thereby reducing the spinnability and stretchability. A finish is then applied. As the finishing agent, a non-aqueous finishing agent diluted with mineral oil or an aqueous dispersion emulsion having a finishing agent concentration of 15 to 35% by weight is applied. The amount of the finishing agent attached to the fiber is 0.5 to 2.5% by weight, preferably 0.7 to 2.0% by weight, based on the wound fiber.

In the stretching step, a heating bath, heated steam spraying, a roller heater, a contact type plate heater, a non-contact type plate heater, or the like can be used, but a roller heater is preferable from the viewpoint of productivity. Moreover, it is preferable that the extending | stretching of this embodiment performs two or more steps | paragraphs multistage hot drawing including the process of cold drawing and hot drawing. In particular, in order to obtain the fiber strength necessary for belt cords and the high degree of fiber orientation (Δn) effective in maintaining rigidity, the cold drawing temperature, the hot drawing temperature, and the ratio of the cold drawing ratio and the hot drawing ratio are important. It becomes.
Cold drawing plays the role of pre-drawing to properly align the fiber orientation before hot drawing. Since the polyamide resin of this embodiment has a high Tg, the cold stretching temperature also requires a high temperature of (Tg-30 ° C.) or higher and Tg or lower. By being (Tg-30 ° C.) or more, the film is uniformly oriented without stretching spots and good strength can be obtained. It can suppress that crystallization advances excessively because it is below Tg. In addition, in uniaxial orientation by stretching, there is a portion called a neck point where the diameter suddenly decreases and the orientation proceeds, but the neck point is stable because the cold stretching temperature is Tg or less. Uniform fibers can be obtained.

  Since the polyamide resin of this embodiment has a high Tg, stretch spots and excessive thermal crystallization are likely to occur during stretching due to insufficient heat or excessive heat. Therefore, in order to obtain a high degree of fiber orientation by high drawing, the distribution of the cold draw ratio and the hot draw ratio is very important. The distribution of the cold draw ratio is preferably 50% or more and 80% or less of the overall draw ratio. When the distribution of the cold draw ratio is 50% or more of the total draw ratio, the necessary pre-drawing is given to the fiber, and a uniform fiber without drawing unevenness can be obtained. Moreover, excessive crystallization by hot stretching can be suppressed. On the other hand, if the distribution of the cold draw ratio is 80% or less of the total draw ratio, the amount of heat necessary for crystallization is given by hot drawing, and excellent strength and Δn can be obtained.

The heat stretching temperature is preferably 200 ° C. or higher and 250 ° C. or lower. When it is 200 ° C. or higher, the amount of heat necessary for crystallization can be provided, and when it is lower than 250 ° C., thermal degradation of the fiber can be suppressed. The overall draw ratio is 2.0 to 7.0 times, preferably 3.0 to 6.0 times.
It is preferable that the drawn fiber is entangled by blowing a high-pressure fluid onto the yarn by an entanglement imparting device before winding. As the entanglement imparting device, a conventional air entanglement device can be used as appropriate. By giving the entanglement to the multifilament, it is possible to prevent the single yarn from converging and to avoid troubles such as cord breakage in post-processing. Moreover, it contributes to the improvement of plunger energy by making breaking elongation high. The number of entanglements is preferably 1 / m to 30 / m, more preferably 1 / m to 20 / m, and still more preferably 1 / m to 15 / m. When the number of entanglement is 1 / m or more, it is possible to suppress the convergence of single yarns. On the other hand, when the number of entanglement is 20 / m or less, damage to the yarn due to entanglement can be reduced.

[Cord for transmission belt]
The drawn yarn of the polyamide multifilament fiber obtained above is twisted to form a cord, which can be used as a transmission belt cord. By twisting the polyamide multifilament fiber, the strength utilization rate is averaged and the fatigue property is improved. The number of twists for the polyamide multifilament fiber of this embodiment is preferably 1 time / m or more. Although there is no restriction | limiting of the form and method of a twisted yarn, It is preferable to twist in the range whose twist coefficient (K) is 300-30000. The twist coefficient (K) is defined by the following formula:
K = Y × D ^0.5 (T / m · dtex ^0.5 )
{Wherein Y is the number of twists per 1 m of polyamide twisted yarn (T / m), and D is the total displayed fineness (dtex) of the polyamide twisted yarn. }. The tension during twisting is preferably 0.01 to 0.2 cN / dtex.

  Furthermore, it is preferable to apply a resorcin-formalin-latex liquid (RFL liquid) to the transmission belt cord of the present embodiment in order to bond the rubber constituting the transmission belt and the cord. The adhesion rate of the RFL resin is preferably 0.5 to 30% by mass with respect to the cord. When the adhesion rate of the RFL resin is 0.5% by mass or more, an adhesive force with the rubber is expressed, and when it is 30% by mass or less, the cord becomes hard and it is possible to avoid deterioration of the bending fatigue property. Usually, the RFL resin is attached after twisting, but may be performed before or during the twisting. The preferred composition of the RFL solution is 0.1 to 10% by weight of resorcin, 0.1 to 10% by weight of formalin and 1 to 28% by weight of latex, and more preferably 0.5 to 3% by weight of resorcin. %, Formalin 0.5-3 mass%, latex 10-25 mass%.

  A transmission belt can be obtained by using the cord or the woven fabric made of the polyamide multifilament fiber thus obtained as a core wire. Examples of the transmission belt include a V-ribbed belt, a wrapped V-belt, a low-edge V-belt, a cogged V-belt, a combined V-belt, a toothed belt, a double-sided V-belt, a double-sided toothed belt, a toothed V-rib belt, and a flat belt.

[Textiles for transmission belts]
The yarn used as the woven fabric for the transmission belt may be a yarn made of only the polyamide multifilament fiber obtained above or a composite yarn in which a polyamide multifilament is covered around a polyurethane elastic yarn. Furthermore, an aramid fiber may be covered around the polyurethane elastic yarn, and the polyamide multifilament of the present embodiment may be covered from above.
In the case of using a yarn composed only of polyamide multifilament fiber, a stretched crimped yarn suitable for a cover cloth of a belt fabric can be obtained by false twisting.

In the case of a composite yarn of polyamide multifilament fiber, the ratio of the polyamide multifilament fiber is 30 wt% or more and 100 wt% or less, preferably 50 wt% or more and 100 wt% or less, more preferably 70 wt% or more and 100 wt%. It is as follows. When the weight of the polyamide multifilament fiber is 30 wt% or less, the rubber adhesiveness and heat resistance are insufficient.
As a means for weaving the transmission belt fabric, it can be produced using a loom such as a rapier room, an air jet room, a water jet room, or a projector room. The woven structure may be any woven structure such as plain weave, twill weave, satin weave, etc., but twill weave is preferable from the viewpoint of the cover factor.

  Stretchable yarns are generally woven as weft yarns for transmission belt fabrics, and drawn yarns are used as warp yarns. As a result, if the stretchable yarns are arranged in the longitudinal direction of the belt, as described above The warp and weft may be reversed. Further, the stretched crimped yarn can be used not only in one direction of the transmission belt fabric but also in both directions.

It is preferable to apply a resorcin-formalin-latex liquid (RFL liquid) to the woven fabric made of polyamide fiber of the present embodiment for adhesion to the rubber constituting the transmission belt. As for the adhesion rate of RFL resin, 5-50 mass% is preferable with respect to a textile fabric. When the adhesion rate of the RFL resin is 5% or more, the elongation of the woven fabric becomes small at the time of molding, and the opening can be reduced. On the other hand, when it is 50% or less, the woven fabric becomes hard and sticks at the time of molding. Can be prevented from becoming impossible.
Usually, the RFL resin is attached after weaving, but may be performed before weaving. The preferred composition of the RFL solution is 0.1 to 10% by weight of resorcin, 0.1 to 10% by weight of formalin and 1 to 28% by weight of latex, and more preferably 0.5 to 3% by weight of resorcin. %, Formalin 0.5-3 mass%, latex 10-25 mass%.
A transmission belt can be obtained by using the woven fabric made of polyamide multifilament fibers thus obtained as a tooth cloth. Examples of the transmission belt include a toothed belt, a double-sided toothed belt, and a toothed V-rib belt.

[Power transmission belt]
The power transmission belt of the present embodiment can be manufactured by a conventionally known manufacturing method. For example, in the case of a toothed belt, a rubber composition for a tooth cloth and an adhesive rubber layer on a peripheral surface of a molding drum having a tooth mold. An unvulcanized sheet is wound, a core wire is spun on the uncured sheet, and further, a rubber composition unvulcanized sheet for the adhesive rubber layer is wound thereon, and then the rubber composition for the compressed rubber layer is not yet wound. A vulcanized sheet is wound to form a laminated body, and then a ring obtained by vulcanizing the laminated body is formed with ribs on the surface with a cutting grindstone and cut into a predetermined width.

EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited to these specific examples.
First, preparation of raw materials, measurement methods, and production methods used in Examples and Comparative Examples are shown below. In this embodiment, 1 kg / cm ² is 0.098 MPa.

[Evaluation of fiber]
(1) (Total) fineness of polyamide multifilament fiber (dtex: decitex)
The weight W and length L of the polyamide multifilament fiber were measured, and the fineness was determined from the formula fineness (d) = 10000 × W (g) / L (m).
(2) Melting point of polyamide multifilament fiber (Tm) (° C)
According to JIS-K7121, it measured using Pyris1-DSC by PERKIN-ELMER. The measurement condition is that the temperature of an endothermic peak (melting peak) that appears when about 10 mg of a sample is heated to 200 to 400 ° C. according to the melting point of the sample at a heating rate of 20 ° C./min in a nitrogen atmosphere is Tm (° C.). It was.

(3) Analysis of copper element (ppm)
The copper element in the fiber was quantified by high frequency inductively coupled plasma (ICP) emission analysis using an IRIS / IP manufactured by Thermo Jarrel Ash.
(4) Fiber strength (cN / dtex)
Using a Shimadzu autograph AGS-500NG, a 25 cm fiber sample was measured at a descent rate of 300 mm / min in accordance with JIS-L1013.
(5) Δn
A compensator U-CTB made by OLYMPUS was attached to a polarizing microscope BX-51P made by OLYMPUS, and Δn was measured.
(6) Loss tangent (tan δ) peak (° C)
Using a dynamic viscoelasticity measuring device DMS-6100 manufactured by Seiko Instruments Inc., a sample having a yarn length of 20 mm, frequency: 10 Hz, strain amplitude: 10 μm, minimum tension / compression force: 50 mN, tension / compression force gain: 1.5, initial value of force amplitude: Measured from −50 ° C. to 270 ° C. at a rate of 2.5 ° C./min under conditions of 50 mN. The tan δ peak at that time was read.

(7) Storage elastic modulus E ′ ratio (E ′ (120 ° C.) / E ′ (25 ° C.))
Using a dynamic viscoelasticity measuring device DMS-6100 manufactured by Seiko Instruments Inc., a sample having a yarn length of 20 mm, frequency: 10 Hz, strain amplitude: 10 μm, minimum tension / compression force: 50 mN, tension / compression force gain: 1.5, initial value of force amplitude: Measured from −50 ° C. to 270 ° C. at a rate of 2.5 ° C./min under conditions of 50 mN. The ratio of the storage elastic modulus E ′ (120 ° C.) at 120 ° C. and the storage elastic modulus E ′ (25 ° C.) at 25 ° C. was defined as “E ′ (120 ° C.) / E ′ (25 ° C.)”. .
(8) Heat resistant strength retention rate (%)
The fiber was wound around the kite at a constant tension and heated in an air environment at 180 ° C. for 12 hours. After allowing to stand overnight and cooling, fiber strength measurement was performed based on JIS-L1013 using Shimadzu Autograph AGS-500NG, and the strength retention before and after heating was calculated.

(9) Rubber adhesion characteristics of fiber (N / cm ² )
In order to evaluate the rubber adhesive property of the fiber under a certain condition, two yarns were twisted under the condition of a twisting factor of 21000 to obtain a cord. Thereafter, an RFL solution is applied so that the adhesion rate of resorcin-formalin-latex (RFL) resin is 5.0% with respect to the cord, the first zone is 160 ° C., the second and third zones are 223 ° C., Drying and heat setting were performed under the condition that the elongation ratio of the delivery cord length and the winding cord length was 105%. After that, a 6.0 mm thick unvulcanized rubber sheet (hydrogenated acrylonitrile / butadiene copolymer) cut into 0.5 cm width × 22 cm length was embedded in the grooved sulfur plate, and the cord was arranged Further, an unvulcanized rubber sheet having a thickness of 6.0 mm was overlaid, press vulcanized at 150 ° C. and 34 MPa for 30 minutes, and then cooled to room temperature. Thereafter, unnecessary portions for measurement were removed, and a T-pull measurement sample having an adhesion measurement length of 0.5 cm was obtained. The adhesive strength of the obtained sample was measured by the method shown in JIS-L1017 (2002) T test (Method A). The measurement speed is 300 mm / min. Then, rubber strength (N / cm ² ) was evaluated by dividing by the surface area S (cm ² ) calculated from the fineness of the yarn embedded with the tenacity (N) of the obtained sample. The surface area S (cm ² ) is defined by the following formula:
S = 0.5 × 10 ⁻³ × (4Dπ / ρ)
{In the formula, D: the total display fineness of the cord (dtex), π: the circularity, and ρ: the density of the cord (g / cm ² ). }.

(10) Heat-resistant adhesive retention of fibers (%)
A rubber sheet was produced under the conditions described in the previous section, and then press vulcanized at 180 ° C. and 34 MPa for 60 minutes. Thereafter, the adhesive strength of the obtained sample was measured by the method shown in JIS-L1017 (2002) T test (Method A). The measurement speed was 300 mm / min.

[Evaluation of code]
(11) Rubber adhesive property of cord (N / cm ² )
In order to evaluate the rubber adhesiveness of the cord, a 6.0 mm thick unvulcanized rubber sheet cut to 0.5 cm width × 22 cm length was embedded in the grooved sulfur plate, and the cord was placed. The unvulcanized rubber sheet having a thickness of 0 mm was overlaid, press vulcanized at 150 ° C. and 34 MPa for 30 minutes, and then cooled to room temperature. Thereafter, a portion unnecessary for measurement was removed to obtain a T-pull measurement sample having an adhesion measurement length Lcm. The adhesive strength of the obtained sample was measured by the method shown in JIS-L1017 (2002) T test (Method A). The measurement speed was 300 mm / min. Then, rubber strength (N / cm ² ) was evaluated by dividing by the surface area S (cm ² ) calculated from the fineness of the yarn embedded with the tenacity (N) of the obtained sample. The surface area S (cm ² ) is defined by the following formula:
S = L × 10 ⁻³ × (4Dπ / ρ)
{In the formula, L: Depth of cord embedded in rubber (cm), D: Total display fineness of cord (dtex), π: Circumference ratio, ρ: Density of cord (g / cm ² ). }.

(12) Heat-resistant adhesive retention of cord (%)
A rubber sheet was produced under the conditions described in the previous section, and then press vulcanized at 180 ° C. and 34 MPa for 60 minutes. Thereafter, the adhesive strength of the obtained sample was measured by the method shown in JIS-L1017 (2002) T test (Method A). The measurement speed was 300 mm / min.

[Evaluation of belt]
(13) Heat resistance retention rate of core wire (%)
Under an ambient temperature of 25 ° C., the load of the driven pulley is 16 hp, the initial tension of the tension pulley is 85 kgf, the drive pulley is driven at a rotational speed of 4900 rpm, the V-ribbed belt is run, and the core wire is exposed from the belt Or the life time (25 ° C.) until the rubber layer was cracked was measured. Similarly, the life time (130 ° C.) in an atmosphere of 130 ° C. was measured, and the life time (130 ° C.) / Life time (25 ° C.) × 100 was defined as the heat resistance retention rate (%) of the core wire.

(14) High-temperature load retention rate of core wire (%)
After heat-treating the V-ribbed belt for 5 hours at an ambient temperature of 150 ° C., the driven pulley load was 16 horsepower, the initial tension of the tension pulley was 85 kgf, and the drive pulley was driven at a rotational speed of 4900 rpm to run the V-ribbed belt. The life time (150 ° C. heat treatment, 130 ° C.) until the core wire was exposed from the belt or the rubber layer was cracked was measured. In addition, using the value of the life time (130 ° C.) described above, the life time (150 ° C. heat treatment, 130 ° C.) / Life time (130 ° C.) × 100 was defined as the high-temperature load resistance retention rate (%) of the core wire.

(15) Heat-resistant retention of tooth cloth (%)
Under an ambient temperature of 25 ° C., it is wound between an 8T drive and driven pulley, subjected to a load of 4 horsepower, a toothed belt running test is performed at a rotational speed of 1500 rpm, and the life time until a tooth is cracked (25 ° C). Similarly, the life time (130 ° C.) in an atmosphere of 130 ° C. was measured, and the life time (130 ° C.) / Life time (25 ° C.) × 100 was defined as the heat resistant retention rate (%) of the tooth cloth.

(16) Heat-resistant retention of tooth cloth (%)
After heat-treating the toothed belt for 5 hours at an ambient temperature of 150 ° C, the belt is wound between an 8T drive and driven pulley under an ambient temperature of 130 ° C, a load of 4 horsepower is applied, and the toothed belt is rotated at 1500 rpm. A running test was conducted, and the life time (150 ° C. heat treatment, 130 ° C.) until the tooth part cracked was measured. Further, using the value of the life time (130 ° C.) described above, the life time (150 ° C. heat treatment, 130 ° C.) / Life time (130 ° C.) × 100 was defined as the high temperature load resistance retention rate (%) of the tooth cloth.

<Example 1>
Polyamide polymerization was carried out by the “hot melt polymerization method”.
The weight of the raw material monomer is 1500 g, and the composition ratio in Table 1 below is set to 816 g (4.74 mol) of 1,4-cyclohexanedicarboxylic acid, 408 g (2.37 mol) of 1,10-decamethylenediamine, And 275 g (2.37 mol) of 2-methylpentamethylenediamine was dissolved in 1500 g of distilled water to prepare an equimolar 50 mass% homogeneous aqueous solution of the raw material monomer. To this homogeneous aqueous solution, 17.0 g of 1,10-decamethylenediamine (0.10 mol, 2.1% based on the total diamine) was added, and the copper concentration was 170 ppm based on the polymer weight after polymerization. Then, potassium iodide and copper iodide were added so that the iodine concentration was 0.68% to obtain an aqueous solution.
The obtained aqueous solution was charged into an autoclave (made by Nitto Koatsu Co., Ltd.) having an internal volume of 5.4 L, kept warm until the liquid temperature (internal temperature) reached 50 ° C., and the inside of the autoclave was purged with nitrogen. The liquid temperature was continuously heated from about 50 ° C. until the pressure in the autoclave tank reached about 2.5 kg / cm ² as gauge pressure (hereinafter, all pressure in the tank was expressed as gauge pressure). (The liquid temperature in this system was about 145 ° C.).

In order to keep the pressure in the tank at about 2.5 kg / cm ² , heating was continued while removing water out of the system, and the solution was concentrated until the concentration of the aqueous solution reached about 75% by mass (the liquid temperature in this system was It was about 160 ° C.). The removal of water was stopped, and heating was continued until the pressure in the tank reached about 30 kg / cm ² (the liquid temperature in this system was about 245 ° C.). Heating was continued until the final temperature was −30 ° C. while removing water out of the system in order to keep the pressure in the tank at about 30 kg / cm ² . After the liquid temperature rose to a final temperature of −30 ° C. (here, 280 ° C.), the pressure was lowered while heating was continued while taking 60 minutes until the pressure in the tank reached atmospheric pressure (gauge pressure was 0 kg / cm ² ). Thereafter, the heater temperature was adjusted so that the final temperature of the resin temperature (liquid temperature) was about 310 ° C. With the resin temperature kept in this state, the inside of the tank was maintained for 10 minutes under a reduced pressure of 100 torr with a vacuum apparatus. Thereafter, it was pressurized with nitrogen to form a strand from the lower nozzle (nozzle), water-cooled and cut, and discharged in a pellet form to obtain a polyamide. The obtained polyamide was dried with a vacuum dryer, and the moisture content was adjusted to 500 ppm.

Table 1 below summarizes the polymerization composition, polymerization conditions, etc. together with other examples. The composition of the fiber after the subsequent spinning process was as shown in Table 1 below.
The polyamide in a dried state is melted at a spinning temperature of 320 ° C., a spinning heater temperature of 320 ° C., and a heating cylinder temperature of 120 ° C. using a melt spinning device (die nozzle nozzle: number of holes 35, hole diameter 0.23 mm, outer diameter 130 mm). Spinning was performed under the conditions of a heating cylinder length of 150 mm and an inner diameter of 170 mm. The temperature difference between the spinneret center and the outer periphery at this time was 1 ° C. Then, after cooling at a cold air speed of 0.9 m / s, a finish was attached at 1.0% by weight with respect to the wound fiber. Next, the film was stretched at a cold stretching temperature of 140 ° C. by 65% of the overall stretching ratio, and further at a hot stretching temperature of 220 ° C. After stretching, entanglement was imparted 8 times / m by a entanglement imparting device, wound with a winder to obtain a 235 dtex polyamide multifilament. Thereafter, the evaluation results of the obtained fibers are shown in Tables 1 and 2 below. The obtained polyamide multifilament fiber had a high Tg and was excellent in fiber uniformity and spinning stability. Further, the values of tan δ of the undrawn yarn and the drawn yarn of Example 1 were as follows. Undrawn yarn: 0.48, drawn yarn 0.20.

<Examples 2 to 4>
Polymers were polymerized in the same manner as in Example 1 under the composition and conditions shown in Table 1 below, and fibers were produced by melt spinning to obtain polyamide multifilament fibers. The evaluation results of the fibers are shown in Tables 1 and 2 below.

<Example 5>
A polyamide multifilament was obtained in the same manner as in Example 1 except that the number of holes of the nozzle nozzle was 240 and the fineness was changed to 1400 dtex. The evaluation results of the fiber were the same as those of Example 1 except for the number of filaments and the fineness.

<Example 6>
A polyamide multifilament was obtained in the same manner as in Example 2 except that the number of holes of the nozzle hole nozzle was changed to 240 and the fineness was changed to 1400 dtex. The evaluation results of the fibers were the same as those in Example 2 except for the number of filaments and the fineness.

<Example 7>
A polyamide multifilament was obtained in the same manner as in Example 3, except that the number of holes in the nozzle nozzle was 240 and the fineness was changed to 1400 dtex. The evaluation results of the fiber were the same as in Example 3 except for the number of filaments and the fineness.

<Example 8>
A polyamide multifilament was obtained in the same manner as in Example 4 except that the number of holes in the nozzle nozzle was 240 and the fineness was changed to 1400 dtex. The evaluation results of the fibers were the same as those in Example 4 except for the number of filaments and the fineness.

<Comparative Example 1>
A polyamide multifilament fiber (manufactured by Asahi Kasei Co., Ltd .: trade name Leona) 235 dtex was used and evaluated based on the measurement method of the example. The evaluation results of this fiber are shown in Table 2 below. In Comparative Example 1, rigidity retention at high temperature was low, and E ′ (120 ° C.) / E ′ (25 ° C.) decreased to 0.39.

<Comparative example 2>
Para-aramid fiber (manufactured by AKZO: trade name Twaron) 220 dtex was used, and evaluation was performed based on the measurement method of the example. The evaluation results of this fiber are shown in Table 2 below. Comparative Example 2 was very rigid, and E ′ (120 ° C.) / E ′ (25 ° C.) hardly decreased.

<Example 9>
Four fibers of Example 1 were combined to obtain 940 dtex, and further, two 940 dtex yarns were twisted under the condition of a twisting factor of 21000 to obtain a cord (the fineness of this twisted yarn was 2000 dtex). Next, an RFL solution is applied so that the adhesion rate (DPU) of resorcin-formalin-latex (RFL) resin is 5.0% with respect to the cord, the first zone is 160 ° C., the second and third zones Was 223 ° C., drying and heat setting were performed under the conditions that the elongation ratio of the delivery cord length and the winding cord length was 105%, and an RFL-treated cord was obtained. The adhesiveness with the rubber at this time is shown in Table 3 below. Example 9 was excellent in adhesion to rubber and heat resistant adhesion retention.

<Examples 10 to 12>
Using the fibers of Examples 2 to 4, the same treatment as in Example 9 was performed to obtain an RFL treated cord. The adhesiveness with the rubber at this time is shown in Table 3 below.

<Example 13>
Two 1400 dtex yarns of Example 5 were twisted under the condition of a twisting factor of 21000 to obtain a cord (the fineness of this twisted yarn was 3000 dtex). Next, an RFL solution is applied so that the adhesion rate (DPU) of resorcin-formalin-latex (RFL) resin is 5.0% with respect to the cord, the first zone is 160 ° C., the second and third zones Was 223 ° C., drying and heat setting were performed under the conditions that the elongation ratio of the delivery cord length and the winding cord length was 105%, and an RFL-treated cord was obtained. The adhesiveness with the rubber at this time is shown in Table 3 below. Example 13 was excellent in adhesion to rubber and heat resistant adhesion retention.

<Examples 14 to 16>
It processed like Example 13 using the fiber of Examples 6-8, and obtained the RFL process code | cord | chord. The adhesiveness with the rubber at this time is shown in Table 3 below.

<Comparative Example 3>
Four fibers of Comparative Example 1 were combined to obtain 940 dtex, and further, two 940 dtex yarns were twisted under the condition of a twisting factor of 21000 to obtain a cord (the fineness of this twisted yarn was 2000 dtex). Next, an RFL solution is applied so that the adhesion rate (DPU) of resorcin-formalin-latex (RFL) resin is 5.0% with respect to the cord, the first zone is 160 ° C., the second and third zones Was 223 ° C., drying and heat setting were performed under the conditions that the elongation ratio of the delivery cord length and the winding cord length was 105%, and an RFL-treated cord was obtained. The adhesiveness with the rubber at this time is shown in Table 3 below. Comparative Example 3 was excellent in rubber adhesion and heat resistant adhesion retention.

<Comparative Example 4>
Four fibers of Comparative Example 2 were combined to make 880 dtex, and further, two yarns of 880 dtex were twisted under the condition of a twisting factor of 21000 to obtain a cord (the fineness of this twisted yarn was 1900 dtex). Next, an RFL solution is applied so that the adhesion rate (DPU) of resorcin-formalin-latex (RFL) resin is 5.0% with respect to the cord, the first zone is 160 ° C., the second and third zones Was 223 ° C., drying and heat setting were performed under the conditions that the elongation ratio of the delivery cord length and the winding cord length was 105%, and an RFL-treated cord was obtained. The adhesiveness with the rubber at this time is shown in Table 3 below. Comparative Example 4 was a rigid fiber, and RFL alone had poor adhesive properties with rubber and a low heat-resistant adhesion retention.

<Example 17>
2 × 3 twist configuration using the fiber of Example 5 (a configuration in which two yarns of 1400 dtex are aligned and provided with a lower twist to give an upper twist together) and a twist factor of 2500 conditions Was twisted to obtain a twisted cord (the fineness of this twisted yarn was 4500 dtex). Subsequently, the RFL solution was applied so that the adhesion rate (DPU) of the resorcin-formalin-latex (RFL) resin was 5.0% with respect to the cord, the first zone was 160 ° C., the second and third zones Was 223 ° C., and the length of the feeding cord and the length of the winding cord were 105%, followed by drying and heat setting to obtain a cord for the cord of the belt.
Next, an unvulcanized sheet of a rubber-coated canvas and an ethylene-propylene-diene rubber blend for the adhesive rubber layer was wound around the peripheral surface of a cylindrical molding drum having a smooth surface. The above-mentioned core wire subjected to adhesion treatment was spun into a spiral shape. Further, after wrapping the unvulcanized sheet of the rubber compound for the same adhesive rubber layer as above, the unvulcanized sheet of the ethylene-propylene-diene rubber compound for the compressed rubber layer is wound. A laminated body was obtained.

The laminate pressure 6 kgf / cm ^2, the external pressure 9 kgf / cm ^2, temperature of 165 ° C., heated and pressurized at a vulcanizer in under conditions of time 35 minutes, then steam vulcanized to obtain an annular substance. Next, the annular object is attached to a first drive system composed of a driving roll and a driven roll, and the annular object is ground using a grinding wheel while traveling under a predetermined tension, and a plurality of surfaces are ground on the surface. Ribs were formed. After that, this annular object is attached to a second drive system composed of another drive roll and a driven roll, and is cut into a predetermined width while running to obtain a product having three ribs and a circumferential length of 1000 mm. V-ribbed belt was obtained. The evaluation results of the cord for cord and the belt at this time are shown in Table 4 below. The cord of Example 17 had high rubber adhesion characteristics and heat-resistant adhesion retention, and the belt using the cord exhibited good heat resistance characteristics.

<Examples 18 to 20>
Using the fibers of Examples 6 to 8, the same treatment as in Example 17 was carried out to produce a cord for cord and a V-ribbed belt using the cord. The evaluation results of the cord for cord and the belt at this time are shown in Table 4 below.

<Comparative Example 5>
Six fibers of Comparative Example 1 are combined to form a 1410 dtex yarn, and a 2 × 3 twist configuration (two yarns of 1410 dtex are aligned and provided with a lower twist to give an upper twist together. Thus, the yarn was twisted under a condition of a twisting factor of 2500 to obtain a twisted cord (the fineness of this twisted yarn was 4500 dtex). Subsequently, the RFL solution was applied so that the adhesion rate (DPU) of the resorcin-formalin-latex (RFL) resin was 5.0% with respect to the cord, the first zone was 160 ° C., the second and third zones Was 223 ° C., and the length of the feeding cord and the length of the winding cord were 105%, followed by drying and heat setting to obtain a cord for the cord of the belt.

Next, an unvulcanized sheet of a rubber-coated canvas and an ethylene-propylene-diene rubber blend for the adhesive rubber layer was wound around the peripheral surface of a cylindrical molding drum having a smooth surface. The above-mentioned core wire subjected to adhesion treatment was spun into a spiral shape. Further, after wrapping the unvulcanized sheet of the rubber compound for the same adhesive rubber layer as above, the unvulcanized sheet of the ethylene-propylene-diene rubber compound for the compressed rubber layer is wound. A laminated body was obtained.
The laminate pressure 6 kgf / cm ^2, the external pressure 9 kgf / cm ^2, temperature of 165 ° C., heated and pressurized at a vulcanizer in under conditions of time 35 minutes, then steam vulcanized to obtain an annular substance. Next, the annular object is attached to a first drive system composed of a driving roll and a driven roll, and the annular object is ground using a grinding wheel while traveling under a predetermined tension, and a plurality of surfaces are ground on the surface. Ribs were formed. After that, this annular object is attached to a second drive system composed of another drive roll and a driven roll, and is cut into a predetermined width while running to obtain a product having three ribs and a circumferential length of 1000 mm. V-ribbed belt was obtained. The evaluation results of the cord for cord and the belt at this time are shown in Table 4 below. Although the cord of Comparative Example 5 was excellent in adhesive properties with rubber, the rigidity decrease at high temperature was large, and the heat resistant retention of the belt was insufficient.

<Comparative Example 6>
Six fibers of Comparative Example 2 are combined to form a 1320 dtex yarn, and a 2 × 3 twisted structure (two yarns of 1320 dtex are aligned and provided with a lower twist to give an upper twist together. Thus, the yarn was twisted under a condition of a twisting factor of 2500 to obtain a twisted cord (the fineness of this twisted yarn was 4200 dtex). Subsequently, after being immersed in an isocyanate compound as the first treatment and in an RFL solution as the second treatment, heat treatment was performed at 200 ° C. to obtain a cord for the cord of the belt.

Next, an unvulcanized sheet of a rubber-coated canvas and an ethylene-propylene-diene rubber blend for the adhesive rubber layer was wound around the peripheral surface of a cylindrical molding drum having a smooth surface. The above-mentioned core wire subjected to adhesion treatment was spun into a spiral shape. Further, after wrapping the unvulcanized sheet of the rubber compound for the same adhesive rubber layer as above, the unvulcanized sheet of the ethylene-propylene-diene rubber compound for the compressed rubber layer is wound. A laminated body was obtained.
The laminate pressure 6 kgf / cm ^2, the external pressure 9 kgf / cm ^2, temperature of 165 ° C., heated and pressurized at a vulcanizer in under conditions of time 35 minutes, then steam vulcanized to obtain an annular substance. Next, the annular object is attached to a first drive system composed of a driving roll and a driven roll, and the annular object is ground using a grinding wheel while traveling under a predetermined tension, and a plurality of surfaces are ground on the surface. Ribs were formed. After that, this annular object is attached to a second drive system composed of another drive roll and a driven roll, and is cut into a predetermined width while running to obtain a product having three ribs and a circumferential length of 1000 mm. V-ribbed belt was obtained. The evaluation results of the cord for cord and the belt at this time are shown in Table 4 below. Although the cord of Comparative Example 5 had good adhesive properties with rubber due to the solvent treatment in two steps, the heat resistant adhesiveness at high temperature was poor and the high temperature load retention rate of the belt was insufficient.

<Example 21>
Using the fiber of Example 1 for warp and weft, a rapier loom (manufactured by Tsuda Koma Kogyo Co., Ltd.) with the following configuration was used to weave the canvas at a rotational speed of 300 rpm.
(Composition of canvas)
(A) Weft: false twisted yarn of Example 1 (friction type false twister, manufactured by Teijin Seiki Co., Ltd .: HTS-15V, false twist speed of 120 m / min, heater temperature of 275 ° C., false twist of about 2000 T / m)
(B) Warp: Example 1 (twist number 180 T / m, twist direction S)
(C) Woven structure: 2/2 twill, warp density 80 / 2.54 cm, weft density 70 / 2.54 cm
A toothed belt in which the warp was attached to the meshing surface of the tooth profile was molded so that the warp was arranged in the length direction of the toothed belt. The toothed belt had a belt width of 19.1 mm, a belt length of 975 mm (annular body), a number of teeth of 92, and a tooth pitch of 9.525 mm. A toothed belt in which the canvas was adhered to the meshing surface of the tooth profile was molded.

(Configuration of toothed belt)
(A) Rubber fabric: N-NBR (hydrogenated acrylonitrile / butadiene copolymer)
(B) Adhesive: RFL (resorcin-formalin-latex, 10% by weight based on the weight of the canvas)
(C) Core wire: glass fiber (dimension: diameter 7 μm × 200 × 3 strands, 0.26 mm spacing)
(D) Molding temperature: 160 ° C
(E) Heating temperature: 20 minutes The toothed belt evaluation results are shown in Table 5 below. The belt using the tooth cloth of Example 21 showed good heat resistance.

<Example 22>
A canvas was produced in the same manner as in Example 21 except that the fibers of Examples 2 to 4 were used for the warp and the weft, and a toothed belt was formed. The toothed belt evaluation results are shown in Table 5 below.

<Comparative Example 7>
Using the fiber of Comparative Example 1 as the warp and weft, a rapier loom (Tsukoma Kogyo Co., Ltd.) was used in the following configuration, and the canvas was woven at a rotational speed of 300 rpm.
(Composition of canvas)
(A) Weft: false twisted yarn of Example 1 (friction type false twister, manufactured by Teijin Seiki Co., Ltd .: HTS-15V, false twist speed of 120 m / min, heater temperature of 275 ° C., false twist of about 2000 T / m)
(B) Warp: Example 1 (twist number 180 T / m, twist direction S)
(C) Woven structure: 2/2 twill, warp density 80 / 2.54 cm, weft density 70 / 2.54 cm
A toothed belt in which the warp was attached to the meshing surface of the tooth profile was molded so that the warp was arranged in the length direction of the toothed belt. The toothed belt had a belt width of 19.1 mm, a belt length of 975 mm (annular body), a number of teeth of 92, and a tooth pitch of 9.525 mm. A toothed belt in which the canvas was adhered to the meshing surface of the tooth profile was molded.
(Configuration of toothed belt)
(A) Rubber fabric: N-NBR (hydrogenated acrylonitrile / butadiene copolymer)
(B) Adhesive: RFL (10% by weight based on the weight of the canvas)
(C) Core wire: glass fiber (dimension: diameter 7 μm × 200 × 3 strands, 0.26 mm spacing)
(D) Molding temperature: 160 ° C
(E) Heating temperature: 20 minutes The toothed belt evaluation results are shown in Table 5 below. The belt using the tooth cloth of Comparative Example 7 had poor rigidity retention at high temperatures and had insufficient heat resistance retention.

<Comparative Example 8>
Using the fiber of Comparative Example 2 for warp and weft, a rapier loom (manufactured by Tsuda Koma Kogyo Co., Ltd.) with the following configuration was used to weave the canvas at a rotational speed of 300 rpm.
(Composition of canvas)
(A) Weft: false twisted yarn of Example 1 (friction type false twister, manufactured by Teijin Seiki Co., Ltd .: HTS-15V, false twist speed of 120 m / min, heater temperature of 275 ° C., false twist of about 2000 T / m)
(B) Warp: Example 1 (twist number 180 T / m, twist direction S)
(C) Woven structure: 2/2 twill, warp density 80 / 2.54 cm, weft density 70 / 2.54 cm
A toothed belt in which the warp was attached to the meshing surface of the tooth profile was molded so that the warp was arranged in the length direction of the toothed belt. The toothed belt had a belt width of 19.1 mm, a belt length of 975 mm (annular body), a number of teeth of 92, and a tooth pitch of 9.525 mm. A toothed belt in which the canvas was adhered to the meshing surface of the tooth profile was molded.
(Configuration of toothed belt)
(A) Rubber fabric: N-NBR (hydrogenated acrylonitrile / butadiene copolymer)
(B) Adhesive: Isocyanate compound, RFL (provided 12% by weight based on the weight of the canvas)
(C) Core wire: glass fiber (dimension: diameter 7 μm × 200 × 3 strands, 0.26 mm spacing)
(D) Molding temperature: 160 ° C
(E) Heating temperature: 20 minutes The toothed belt evaluation results are shown in Table 5 below. The belt using the tooth cloth of Comparative Example 8 had poor rubber adhesion characteristics at high temperatures, and the high temperature load retention rate was insufficient.

  By using the multifilament fiber made of the novel high-melting-point polyamide resin according to the present invention for a transmission belt cord and / or woven fabric, the transmission belt cord, the woven fabric, excellent in rubber adhesion and durability at high temperatures, And a transmission belt can be provided.

Claims (13)

It consists of a polycondensate of a dicarboxylic acid containing an alicyclic dicarboxylic acid and a diamine, the ratio of the alicyclic dicarboxylic acid to the dicarboxylic acid is 50 mol% or more, and the storage elastic modulus E ′ at 120 ° C. The ratio of storage elastic modulus E ′ (25 ° C.) at (120 ° C.) to 25 ° C., and the value of E ′ (120 ° C.) / E ′ (25 ° C.) is 0.6 or more and 0.9 or less. Polyamide fiber for transmission belts.   2. The polyamide fiber for a transmission belt according to claim 1, wherein the heat-resistant adhesion retention ratio with the rubber after heat treatment at 180 ° C. for 5 hours is 80% or more. The polyamide fiber for a transmission belt according to claim 1 or 2, wherein the rubber adhesion property measured according to JIS L1017: 2002 Annex 1 (3.1 T test) is 1000 N / cm ² or more. The polyamide fiber for a transmission belt according to any one of claims 1 to 3 , wherein Δn of the polyamide fiber is 0.04 or more. The polyamide fiber for a transmission belt according to any one of claims 1 to 4 , wherein the polyamide fiber contains 1 ppm to 500 ppm of copper element. The polyamide fiber for a transmission belt according to any one of claims 1 to 5 , wherein the tensile strength is 4.0 cN / dtex or more. The polyamide fiber for a transmission belt according to any one of claims 1 to 6 , wherein the heat resistant strength retention after heat treatment in an air environment at 180 ° C for 12 hours is 70% or more. The polyamide fiber for a transmission belt according to any one of claims 1 to 7 , wherein the single yarn fineness is 0.5 dtex or more and 10 dtex or less. A transmission belt cord obtained by treating the alicyclic polyamide fiber for a transmission belt according to any one of claims 1 to 8 with a resorcin-formalin-latex resin. The transmission belt cord according to claim 9 , wherein the rubber adhesion property measured in accordance with JIS L1017: 2002 Annex 1 (3.1 T test) is 1000 N / cm ² or more. Transmission belt with transmission belt cord according as belt cords in claim 9 or 10. A woven fabric for a transmission rubber belt, wherein the polyamide fiber for a transmission belt according to any one of claims 1 to 8 is used as a woven yarn for any one of the backgrounds. A power transmission belt using the power transmission belt fabric according to claim 12 as a belt tooth cloth.