JP2009062653A - Reinforcing fiber cord for hose and hose - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforcing fiber cord for a hose which is especially excellent in fatigue resistance, and a hose for pressurized fluid such as automotive use, construction machine use, aircraft hydraulic hose, etc., reinforced with the cord. <P>SOLUTION: The reinforcing fiber cord for a hose is formed of a spun yarn of a fiber wherein 95 mol% or more of the repeating unit is a polyketone expressed by formula (1), and having an average fiber length of the spun yarn of 300-2,000 mm. The spun yarn is preferably a yarn produced by draft zone system spinning process. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a reinforcing fiber cord for a hose and a hose, and particularly relates to a reinforcing fiber cord for a hose excellent in fatigue resistance and a hose reinforced with the cord.

  The present applicant has previously proposed a spun yarn of a fiber composed of polyketone (hereinafter referred to as “polyketone fiber”) in Patent Document 1, and has high strength, excellent appearance and texture, It is a spun yarn excellent in processability such as process passability, and a check spun yarn having an average fiber length of 10 to 200 mm is disclosed as an example. Although this spun yarn is useful for rubber reinforcements such as hoses, no improvement has been studied for improving the fatigue resistance of hoses.

Japanese Patent Laid-Open No. 2003-082542

  An object of the present invention is to provide a reinforcing fiber cord for a hose particularly excellent in fatigue resistance and a hose reinforced with the cord.

（２）紡績糸が、牽切紡績糸であることを特徴とする上記（１）に記載のホース用補強繊維コード。
（３）上記（１）又は（２）に記載のホース用補強繊維コードで補強されたことを特徴とするホース。 The inventor of the present invention has reached the present invention as a result of intensive studies to solve the above-mentioned problems.
That is, the present invention is as follows.
(1) 95% by mole or more of repeating units is a reinforcing fiber cord for a hose composed of a spun yarn of a fiber composed of a polyketone represented by the following formula (1), and the spun yarn has an average fiber length of 300 Reinforcing fiber cord for hose characterized by being -2000 mm.

(2) The reinforcing fiber cord for a hose as described in (1) above, wherein the spun yarn is a check spun yarn.
(3) A hose that is reinforced with the reinforcing fiber cord for a hose according to (1) or (2).

  ADVANTAGE OF THE INVENTION According to this invention, the hose reinforced with the reinforcement fiber cord for hoses excellent in especially fatigue resistance and this cord is provided.

The present invention will be specifically described below.
The hose in the present invention is typically a pressurized fluid hose such as an automobile hose, a construction machine hose, an aircraft hydraulic hose, a marine hose, specifically, a water hose, a radiator hose, a brake, etc. A hose, a power steering hose, an air hose, etc. are mentioned.
These hoses are generally made of acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR), hydrogenated acrylonitrile butadiene rubber (HNBR), natural rubber, styrene butadiene rubber (SBR), alkylated chlorosulfonated polyethylene (ACSM). ), Epichlorohydrin, olefin-vinyl ester copolymer, ethylene-propylene-diene rubber (EPDM) or other inner tube composed of a tube rubber, CR, chlorosulfonated polyethylene rubber (CSM), The reinforcing layer is arranged between the outer layer made of a cover rubber made of singly or blend of chlorinated polyethylene rubber (CPE), natural rubber, SBR or the like.

  Reinforcing layers include reinforcing cords that are braided (braided up) or spiral, knitted fabrics such as raschel using reinforcing cords (especially useful for hoses with varying pipe diameters), and particularly high pressure resistance. Examples include a reinforcing layer formed of a woven fabric, which is useful for a required hose and in which the reinforcing fiber cord for the hose is preferably arranged in the longitudinal direction of the hose, and the reinforcing layer may be one layer or two layers or more. In this case, an intermediate rubber layer (using the same kind of elastomer as the inner tube and the outer tube) may be disposed between the respective layers. By the way, in automotive hoses where relatively high temperature oil flows in the inner pipe, when there are multiple reinforcing layers, the reinforcing layer excluding the innermost layer of the hose is composed of the spun yarn of the polyketone fiber of the present invention. It is preferable to use the reinforcing fiber cord for hose, and the reinforcing layer of the innermost layer is preferably a reinforcing fiber cord using a fiber having excellent heat resistance such as an aramid fiber.

但し、Ｒは、エチレン以外の炭素数１〜３０の有機基であり、例えば、プロピレン、ブチレン、１−フェニルエチレン等の基であり、Ｒの水素原子の一部または全部が、ハロゲン基、エステル基、アミド基、水酸基、エーテル基で置換されていてもよい。もちろん、Ｒは二種以上であってもよく、例えば、プロピレン基と１−フェニルエチレン基が混在していてもよい。 In the polyketone constituting the polyketone fiber of the present invention, 95 mol% or more, preferably 98 mol% or more, particularly 99.6 mol% or more of the repeating unit is represented by the above formula (1). The polyketone may contain a repeating unit other than the above formula (1), for example, one represented by the following formula (2) within a range of less than 5 mol%.

Where R is an organic group having 1 to 30 carbon atoms other than ethylene, for example, a group such as propylene, butylene, 1-phenylethylene, etc., and a part or all of the hydrogen atoms of R are halogen groups, esters It may be substituted with a group, an amide group, a hydroxyl group or an ether group. Of course, R may be two or more, for example, a propylene group and a 1-phenylethylene group may be mixed.

式中のｔ及びＴは、それぞれヘキサフルオロイソプロパノール（セントラル硝子（株）社製）及び該ヘキサフルオロイソプロパノールに溶解したポリケトンの希釈溶液の２５℃での粘度管の流過時間である。Ｃは、上記希釈溶液の濃度であり、ヘキサフルオロイソプロパノール１００ｍｌ中のポリケトンの質量（ｇ）である。 The intrinsic viscosity [η] of the polyketone is preferably 1 dl / g or more, more preferably 2 dl / g or more, particularly preferably 4 dl / g or more, preferably 20 dl / g or less, more preferably 15 dl / g or less, particularly Preferably it is 10 dl / g or less.
The intrinsic viscosity [η] is a value obtained based on the following definition formula.

In the formula, t and T are the flow times of the viscosity tube at 25 ° C. of hexafluoroisopropanol (manufactured by Central Glass Co., Ltd.) and a dilute solution of polyketone dissolved in the hexafluoroisopropanol, respectively. C is the concentration of the diluted solution, and is the mass (g) of polyketone in 100 ml of hexafluoroisopropanol.

The polyketone may contain additives such as antioxidants, radical inhibitors, other polymers, matting agents, ultraviolet absorbers, flame retardants, and metal soaps as necessary.
The shape of the polyketone fiber may be uniform or thick in the length direction, and the cross-sectional shape of the fiber may be round, triangular, L-shaped, T-shaped, Y-shaped, W-shaped, Yaba-shaped, flat (With flatness of about 1.3-4, W type, I type, boomerang type, wave type, skewer type, eyebrows type, rectangular parallelepiped type, etc.), polygonal type such as dogbone type, multileaf It may be a mold, a hollow mold, or an irregular shape.

Next, as preferable characteristics of the polyketone fiber, the tensile strength is 5 cN / dtex or more, more preferably 10 cN / dtex or more, particularly preferably 15 cN / dtex or more, 30 cN / dtex or less, and the tensile elongation is 3%. Or more, more preferably 3.5% or more, particularly preferably 4% or more, 15% or less, more preferably 10% or less, still more preferably 8% or less, and particularly preferably 6% or less. Is 100 cN / dtex or more, more preferably 200 cN / dtex or more, particularly preferably 300 cN / dtex or more, and 1000 cN / dtex or less.
The preferred single yarn fineness of the polyketone fiber is 0.01 to 10 dtex, more preferably 0.1 to 3 dtex, and particularly preferably 0.5 to 3 dtex.

The present invention is a reinforcing fiber cord for a hose using a spun yarn of such polyketone fiber, and the average fiber length of the spun yarn needs to be 300 to 2000 mm, preferably 350 mm or more, more preferably 400 mm or more, Particularly preferably, it is 450 mm or more, preferably 1700 mm or less, more preferably 1500 mm or less, and particularly preferably 1200 mm or less. If the average fiber length is less than 300 mm and more than 2000 mm, the object of the present invention is not achieved.
In the present invention, as the spun yarn, a check spun yarn is preferable, and when the average fiber length is L, it is preferable that short fibers having a length of 1.5 L or more have a ratio of 10 to 25%. The short fibers having a length of 1.5 L or more are preferably 12% or more, particularly preferably 15% or more, preferably 23% or less, particularly preferably 20% or less.

Here, the average fiber length L is a value obtained by dividing the number obtained by multiplying the fiber length and the number of fibers in the staple diagram by the total number of fibers, and 10 to 25% of short fibers having a length of 1.5 L or more. Having in proportion means that a value obtained by dividing the number of short fibers having a length of 1.5 L or more by the total number of fibers is 10 to 25%.
If the ratio of short fibers having a length of 1.5 L or more is less than 10%, the strength may be insufficient, and if it exceeds 25%, fatigue resistance may be reduced.
Furthermore, it is preferable that the short fiber having a length of 0.5 L or less is 10% or more, particularly preferably 15% or more, 25% or less, particularly preferably 20% or less, and less than 10%. Fatigue resistance may decrease, and if it exceeds 25%, high strength may be difficult to obtain.

The total fineness of the spun yarn is preferably 30 to 1100 dtex, particularly preferably 55 to 800 dtex.
Further, the spun yarn may be used after being additionally twisted, and the twisting coefficient (K) of the additional twist calculated by the following formula may be selected in the range of 1000 to 10,000. In addition, it may be used in a conventional manner, for example, by twisting and then twisting to form a twin yarn or triplet, or by combining two or more spun yarns and then conjugating them using a swivel conjugation nozzle. A combination of can also be used.
Twisting coefficient (K) = number of twists × total fineness of spun yarn (dtex) ^1/2

The spun yarn used in the present invention includes composite spun yarn such as silospan, silofil, and core yarn in addition to the spun yarn after fine spinning, and particularly a core-sheath structured yarn (sheath sheath) in which a polyketone fiber is disposed in the core. The part is preferably exemplified by the following mixed fibers.)
The spun yarn used in the present invention may be 100% polyketone fiber, but if necessary, it is preferably in the range of 50% by mass or less, other than polyketone fiber, for example, natural fibers such as cotton and wool, rayon. Cellulose fibers such as fibers, lyocell fibers, polyester fibers, polyamide fibers, aramid fibers (para and meta), polyvinyl alcohol fibers, wholly aromatic polyester fibers, poly (p-phenylenebenzobisoxazole) fibers, ultrahigh molecular weight polyolefins Various known fibers (long fibers or short fibers, which may be used in combination) such as fiber, carbon fiber, ceramic fiber, glass fiber, metal fiber, and the like may be mixed by twisting, blending, or the like.

  As a suitable method for producing the spun yarn used in the present invention, the one exemplified in FIG. 1 can be cited, and while the polyketone fiber tow or multifilament A is drawn and overlapped in front of the supply nip roller 1, After passing the supply nip roller 1, it is simultaneously torn in the shooter 2 by the check nip roller 3, and uniformly checked while being drafted to obtain a short fiber bundle. Next, after being torn off from the check nip roller 3 by the suction air nozzle 4, and further provided with a binding unit by winding the fluff of short fibers together with the swirling conjugation nozzle 5, and then by the delivery roller 6 It is taken up and becomes a yarn 7 in which the fluffs of short fibers are randomly wound.

Further, two series of steps illustrated in FIG. 1 are provided, and each of the swirling conjugation nozzles 5 is provided with a binding portion by wrapping the fluff of short fibers together with the entanglement, and then combining the two. It may be picked up by the delivery roller 6 after being conjugated by a swivel conjugated nozzle (not shown).
The spun yarn thus obtained is made into a twin yarn or triplet by a conventional method, for example, a lower twist and then an upper twist, or two or more spun yarns are combined, and then a swivel conjugated nozzle And may be used in combination.
Further, the short fiber bundle obtained by checking may be used as a spun yarn through a general drawing, roving, and spinning process according to a conventional method. Especially, the ring spun yarn has a softer texture. This is preferable.
Further, when checking, a conventional perlock type or turbo type may be used.

In the present invention, for example, a method of setting the ratio of short fibers having a length of 1.5 L or more to 10 to 25%, a method of setting a draft at the time of checking low, a supply nip roller 1 and a checking nip roller 3, etc. There is a method of providing a regular polygonal middle roller in between. This method is also suitable as a method for adjusting the ratio of short fibers having a length of 0.5 L or less to 10 to 25%.
The reinforcing fiber cord for hose of the present invention is composed of spun yarn of such polyketone fiber, but when used as a reinforcing fiber cord for hose, it may be RFL-treated.

RFL treatment refers to treatment with a mixed solution containing resorcin, formalin and latex, and the preferred adhesion amount of the RFL resin is 1 to 10% by mass, particularly 2 to 7% by mass with respect to the fibers.
A preferred molar ratio (F / R) of formalin (F) to resorcin (R) is in the range of 1.0 to 2.2, particularly preferably 1.0 to 1.9. The ratio (RF / L) of resorcin and formalin total mass (RF) to L) is preferably in the range of 5 to 25% by mass, particularly 5 to 17% by mass. Furthermore, the total amount of sodium hydroxide and ammonium hydroxide and resorcin ( The molar ratio (NaOH + NH ₄ OH / R) to R) is preferably 0.21 or less.

  The latex is preferably a latex corresponding to the type of elastomer used for the inner tube or the outer tube. For example, styrene-butadiene-vinylpyridine terpolymer, chlorosulfonated polyethylene (CSM), alkylated chlorosulfonated polyethylene. Latex such as (ACSM), hydrogenated acrylonitrile butadiene rubber (HNBR), epichlorohydrin, natural rubber, styrene-butadiene rubber (SBR), chloroprene rubber, olefin-vinyl ester copolymer, ethylene-propylene-diene rubber (EPDM) Is mentioned.

Prior to the RFL treatment, pretreatment with an epoxy compound or an isocyanate compound may be performed.
As a method of RFL treatment, it may be applied to a spun yarn of polyketone fiber, or it is treated with RFL treatment in a state where a long fiber of polyketone fiber is twisted as necessary, and then cut to obtain a short fiber for spinning. It can be used as a thread. The number of twists is preferably a sweet twist of about 100 to 700 in terms of a twist coefficient (K1) represented by the following formula, but may be a medium to strong twist of about 30000.
T1 = K1 / D ^1/2
In the formula, T1 = twist number (T / m), D = fineness (dtex) of the yarn supplied to the RFL treatment.
Furthermore, RFL treatment may be performed after forming a knitted or woven fabric using a reinforcing fiber cord for a hose made of spun yarn of polyketone fiber.

In the present invention, a reinforcing layer is formed using a reinforcing fiber cord for a hose made of spun yarn of polyketone fiber, but all the reinforcing layers may be composed of the reinforcing fiber cord for a hose of the present invention. If necessary, preferably in the range of 50% by mass or less, the reinforcing fiber cords for hoses using fibers mixed with the polyketone fibers described above may be combined, knitted, knitted or woven, etc. For example, in a woven fabric, one or several warps and / or wefts may be used alternately. Alternatively, one S strand and Z twist yarn of the same fiber cord or different fiber cords may be used alternately.
Further, when forming a plurality of reinforcing layers, it is sufficient that at least one of the reinforcing layers is formed using the reinforcing fiber cord for hose of the present invention. One to several layers may be alternately stacked.

  For example, for the purpose of suppressing a decrease in the tensile strength of the polyketone fiber by receiving strong ultraviolet rays outdoors, for example, an ultraviolet absorbent (for example, benzophenone series, benzotriazole series, hindered amine) in the form of fiber or spun yarn or woven or knitted fabric. There are one type or a combination of two or more types) and / or ultraviolet screening agents (for example, fine particles of titanium oxide, iron oxide, cerium oxide, etc.), and the average particle size is preferably 0.01 to 0.6 μm. ) Is preferably contained. Examples of the method of inclusion include a method of applying or coating a resin or a film containing an ultraviolet absorber and / or an ultraviolet shielding agent to fibers, spun yarn, woven or knitted fabric, etc., and an ultraviolet absorbing material and / or an ultraviolet shielding agent. The content of is preferably 0.001 to 10% by mass relative to the mass of the resin or film.

The present invention will be described more specifically based on examples, but the present invention is not limited to these examples.
The measurement method and evaluation method in the present invention are as follows.
(1) Tensile strength, tensile elongation, and tensile modulus of fiber Measured according to JIS-L-1013.
Sample length: 20 cm, tensile speed: measured at 20 cm / min, and an average value is obtained when measured 20 times.

(2) Tensile strength of spun yarn The yarn twisted with the twist coefficient 5450 is measured.
Twist factor (K) = twist number × total fineness of spun yarn (dtex) ^1/2
(3) Hose fatigue test The inner diameter of the thermoplastic elastomer made of ACM (acrylic rubber: manufactured by Nippon Zeon) was used as the inner tube, the reinforcing fiber cord of the example was bladed on the outer side, and the ACM thermoplastic elastomer was placed as the outer tube. A hose having a diameter of 9.5 mm and an outer diameter of 17.4 mm was produced. The hose was subjected to an impact pressure test in accordance with JIS-K-6375, 7.7. The test oil used was a mineral oil corresponding to two kinds specified in JIS-K-2313, and a rectangular wave having a maximum pressure of 2700 N / cm ² was repeatedly applied at an oil temperature of 93 ° C., and the number of impact pressures leading to fracture was measured.

[Example 1]
Using the apparatus shown in FIG. 1, a polyketone fiber multifilament yarn of 1670 dtex / 1250f (manufactured by Asahi Kasei Fibers Co., Ltd .; trademark Cyvalon; tensile strength 18 cN / dtex, tensile elongation 5%, tensile elastic modulus 350 cN / dtex) The short fiber bundle torn at a speed of 300 m / min between the supply nip roller 1, the shooter 2 and the check nip roller 3 (check length 120 cm) at a speed of about 5.7 times (draft during check). Subsequently, the yarn was passed through the suction air nozzle 4 and the swirl conjugated nozzle 5, and a spun yarn of 330 dtex with a binding portion was obtained by winding the fluff of short fibers together with the entanglement.
The obtained spun yarn had a strength of 13.6 cN / dtex, an average fiber length (L) of 450 mm, a ratio of 1.5 L or more and 0.5 L or less of 16 to 18%.
Seven spun yarns were combined and 220 T / m twist was added to obtain a reinforcing fiber cord.
The result of the hose fatigue test was excellent in fatigue resistance with 150,000 impact pressures.

[Examples 2-4, Comparative Examples 1-2]
In Example 1, the check length was changed to obtain a short fiber bundle in which the average fiber length (L) was changed, and the result of the hose fatigue test using the reinforcing fiber cord obtained in the same manner as in Example 1 was When the average fiber length (L) is 300 mm (Example 2), the spun yarn strength is 13.6 cN / dtex, the impact pressure is 130,000 times, and the average fiber length (L) is 1200 mm (Example 3). Has a spun yarn strength of 13.8 cN / dtex and an impact pressure of 150,000 times, and an average fiber length (L) of 2000 mm (Example 4) has a spun yarn strength of 13.8 cN / dtex and an impact pressure of 130,000 times. It was excellent in fatigue resistance.
The one with an average fiber length (L) of 250 mm (Comparative Example 1) has a spun yarn strength of 13.4 cN / dtex, an impact pressure of 90,000 times, and an average fiber length (L) of 2200 mm (Comparative Example 2). Compared to Example 1, the spun yarn strength was 13.8 cN / dtex and the impact pressure was 100,000, which was inferior in fatigue resistance.

[Example 5]
The strength of the ring spun yarn obtained by ring-spinning the short fiber bundle obtained in Example 1 according to a conventional method was 13.5 cN / dtex. The result of the hose fatigue test using the reinforcing fiber cord obtained from the spun yarn obtained in the same manner as in Example 1 is excellent in fatigue resistance as in Example 1 with 150,000 impact pressures. there were.

  The present invention provides a reinforcing fiber cord for a hose particularly excellent in fatigue resistance and a hose reinforced with the cord. The spun yarn used in the present invention is, for example, a core wire such as a conveyor belt or a transmission belt, a reinforcing fabric, a toothed belt tooth fabric (particularly the core yarn is an elastic yarn or a stretch processed yarn, and the spun yarn used in the present invention. Is useful for tooth fabrics using covering yarn in the longitudinal direction of the belt), reinforcing fabric for air springs and diaphragms, gut for tennis and badminton (especially multi (and mono) filament yarns such as nylon as the core yarn) It is also effective to use the spun yarn used in the present invention as a gut which is a side yarn.

It is a side view which shows an example of the method of manufacturing the spun yarn of this invention.

Explanation of symbols

A: Tow or multifilament 1: Supply nip roller 2: Shooter 3: Checking nip roller 4: Suction air nozzle 5: Swivel conjugation nozzle 6: Delivery roller 7: Yarn

Claims (3)

A reinforcing fiber cord for a hose composed of a spun yarn of fibers composed of a polyketone represented by the following formula (1) with 95 mol% or more of the repeating unit, wherein the spun yarn has an average fiber length of 300 to 2000 mm A reinforcing fiber cord for a hose characterized by being.

  The reinforcing fiber cord for a hose according to claim 1, wherein the spun yarn is a check spun yarn.   A hose reinforced with the reinforcing fiber cord for a hose according to claim 1.

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