US3605818A - High pressure hose - Google Patents

Abstract

METHOD OF MAKING A PACKAGE OF REINFORCING RIBBON. INVOLVES IMPREGNATING SUBSTANTIALLY UNTWISTED MUTI-FILAMENT YARNS WITH WET POLYMERIC BINDER, BRINGING THE IMPREGNATING YARNS TOGETHER IN A SIDE-BY-SIDE RELATIONSHIP WITH ADJACENT EDGES TOUCHING, WINDING THE YARNS ABOUT A CORE WHILE STILL WET WITH THE BINDER, AND DRYING. FURTHER RELTES TO RESULTING RIBBON PACKAGE, WHEREIN THE YARNS ARE BONDED TO ONE ANOTHER AT THEIR ADJACENT EDGES TO FORM THE RIBBON AND WHEREIN ADJACENT LAYERS OF THE RIBBON ARE WEAKLY BONDED TO ONE ANOTHER, SO THAT AN OUTER RIBBON LAYER IS READILY STRIPPABLE FROM A LAYER THEREBENEATH. ALSO DISCLOSES A TEXTILE-REINFORCED HIGH PRESSURE HOSE UTILIZING THE RIBBON IN THE TEXTILE REINFORCEMENT. HOSE COMPRISES A RUBBERY INTERIOR TUBE, A PLY OF REINFORCING TEXTILE WRAPPED THEREAROUND, AND A SECOND RUBBERY TUBE DISPOSED ABOUT THIS PLY, THE REINFORCING TEXTILE BEING MADE UP OF THE POLYMERIC BINDER-IMPREGNATED RIBBON, THE INTERIOR AND SECOND RUBBERY TUBES BEING VULCANIZED TO THE BINDER AND HENCE TENACIOUSLY SECURED TO THE BINDER-IMPREGNATED TEXTILE PLY.

Description

Sept. 20, 1971 A. J. BALCHAN HIGH PRESSURE HosE Filed Jan. 2, 1968 MQWW United States Patent O 3,605,818 HIGH PRESSURE HOSE Adolph J. Balchan, Paterson, NJ., assignor to Uniroyal, Inc., New York, N.Y. Filed Jan. 2, 1968, Ser. No. 695,163 Int. Cl. F161 1]/08 U.S. Cl. 138-126 7 Claims ABSTRACT OF THE DISCLOSURE Method of making a package of reinforcing ribbon. Involves impregnating substantially untwisted multi-lilament yarns with wet polymeric binder, bringing the impregnating yarns together in a side-by-side relationship with adjacent edges touching, winding the yarns about a core while still wet with the binder, and drying. Further relates to resulting ribbon package, wherein the yarns are bonded to one another at their adjacent edges to form the ribbon and wherein adjacent layers of the ribbon are weakly bonded to one another, so that an outer ribbon layer is readily strippable from a layer therebeneath. Also discloses a textile-reinforced high pressure hose utilizing the ribbon in the textile reinforcement. Hose comprises a rubbery interior tube, a ply of reinforcing textile wrapped therearound, and a second rubbery tube disposed about this ply, the reinforcing textile being made up of the polymeric binder-impregnated ribbon, the interior and second rubbery tubes being vulcanized to the binder and hence tenaciously secured to the binder-impregnated textile ply.

BACKGROUND OF THE INVENTION (l) Field of the invention This invention relates to the production of reinforcing ribbon for use in the manufacture of high pressure hose or other like textile-reinforced rubbery articles. More particularly, the invention relates to the production of a reinforcing ribbon from substantially no twist multifilament yarns and to the use of such ribbon as a textile reinforcement for medium and high pressure hose.

(2) Description of the prior art Textile-reinforced rubbery articles, e.g., hoses, are well known in the art. Heretofore it has been conventional to utilize a plurality of twisted multi-filament yarns in the braiding or spiral wrapping operation to form the reinforcing textile ply. Typically each such yarn was given a standard industrial twist of the order of from about 2 to 3 turns per inch. Such twisting was carried out for a number of purposes. Thus, it tended 'to keep the individual filaments making up the yarns from fraying and separating when the yarns were processed on hose making machinery. Additionally, it tended to concentrate the yarn strength in a small area.

However, the use of such twisted yarns has posed a number of serious problems. Thus, in commercial production it is customary to use twisted yarns in a one, two, three, or four end put-up. In other words, to supply the hose braider machine, the twisted yarns are first wound on a bobbin to provide a yarn package, the bobbin being wound with a single yarn, a pair of yarns, or three or four yarns, as required. Where two or more yarns are to be wound on the bobbin, these yarns are not bonded ice to one another. Accordingly, it has been found that in the subsequent hose braiding operation, numerous faults occur. These faults include: the separation of the yarn ends with a resulting non-uniform lay of yarns, loose yarns, buckling of loose yarn ends, sloughed yarns, bad builds on the bobbin, e.g., dropped yarn ends, telescoping of yarns wrapped on the bobbin, etc. These faults, in turn, either result in the production of defective hose with consequent production loss, or else the hose making machinery must be stopped to correct such faults, leading to expensive down time.

Another problem arising from the use of twisted multilament yarns in the production of high pressure hose is that known in the art as wicking Thus, it is conventional to treat twisted multilament yarns with a binder so as to promote adhesion to the yarns of a subsequently applied rubbery material. However, such 'treatment tends to be essentially a surface treatment of the twisted yarns with the binder. Accordingly, a common problem has arisen when the resulting high pressure hose (employing such yarns as the fabric reinforcement) is used to convey gases under pressure, namely, longitudinal wicking of the gas through the yarns. This can result in hose ply separation. The wicking problem is discussed in detail in Rubber World, September 1967, p. 58.

SUMMARY OF THE INVENTION The present invention provides a method for the production of a package of reinforcing ribbon for use in the manufacture of pressure hose and other textile-reinforced rubber articles. The method involves impregnating multifilament yarns, these yarns being characterized by substantially no twist, with a polymeric binder in an amount equal to at least ten per cent by weight of the yarns (expressed on a dry basis), bringing the yarns together in side-by-side substantially parallel relationship with their adjacent edges touching, winding the yarns about a core while the yarns are still wet with the polymeric binder, and drying. The drying serves to bond the yarns to one another at their adjacent edges to form the ribbon and additionally to weakly bond adjacent layers of the ribbon to one another. The resulting package of reinforcing ribbon holds its form, has no tendency whatsoever to telescope, 'the ribbon is characterized by high tensile strength, and the outermost layer of ribbon is readily strippable from the layers therebeneath.

The invention further comprehends a high pressure rubbery hose that has been textile-reinforced by use of the foregoing ribbon, as by braiding, spiral wrapping, or the like. Such high pressure hose comprises a rubbery in- Iterior tube, a ply of reinforcing textile wrapped therearound, and a second rubbery tube disposed about said ply, the reinforcing textile comprising the foregoing ribbon, as in the form of braid, spiral wrap, or the like, the ribbon being impregnated with the polymeric binder, the interior and second rubbery tubes being vulcanized to the binder and hence tenaciously secured to the fabric ply.

BRIEF DESCRIPTION OF THE DRAWING My invention will be further understood by the following detailed description taken in conjunction with the accompanying drawing wherein: Y

FIG. 1 is a schematic perspective view, partially in section, illustrating suitable apparatus for carrying out the method of my invention;

FIG. 2 illustrates a single multitilarnent yarn of substantially no twist, i.e., not greater than one-half turn per inch;

FIG. 3 illustrates my package of reinforcing ribbon, with adjacent layers of ribbon strippably secured to one another, and with the four individual yarns at the end of the ribbon having been partially separated from one another; and

FIG. 4 is a view in partial section of a high pressure hose made in accordance with my invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with one aspect of my invention, I have developed a method of making a package of reinforcing ribbon suitable for the production of high pressure rubber hose or like textile-reinforced rubber articles. In essence, this method involves impregnating multilament yarns characterized by substantially no twist with a polymeric binder in an amount equal to at least ten percent by weight of said yarns on a dry basis, bringing the yarns tgether in a side-by-side substantially parallel relationship with their adjacent edges touching, winding the yarns about a core, e.g., a spool or bobbin, while the strands are still wet with the polymeric binder, and drying so as to bond the yarns to one another at their adjacent edges via the polymeric binder so as to form the ribbon, and additionally to weakly bond adjacent layers of the ribbon to one another, such that the outermost ribbon layer can be readily stripped from an adjacent layer therebeneath.

Referring now to the drawing, and particularly to FIG. 1, there is schematically illustrated means for carrying out the method of my invention. These means generally include a plurality of containers 10, each each containing a spool about which is wrapped a multilament yarn characterized by substantially no twist (the spool and wrapped yarn not being shown), eyelet guides 12 and 14, a vessel 16 containing therein a bath 18 containing polymeric binder material, eyelet guides 20 and 22, pigtail guide 24, yarn tensioning device 26, reciprocating yarn guide 28, and pick-up bobbin 30.

In practicing the method of my invention, I utilize two or more multililament yarns to make up the reinforcing ribbon. As illustrated in FIG. l, four such yarns are employed. Generally I have found it best to employ from about 2 to l2 yarns in making the ribbon. Thus, while more than l2 yarns could be employed, it would serve no particular advantage. Preferably, the ribbon is formed from 3 to 6 yarns.

I have found that it is essential to my invention that the multitilament yarns be characterized by substantially no twist. By substantially no twist I mean a twist of from zero to no more than 0.5 turn per inch, and this expression is intended to designate the foregoing definition throughout the speciiication and claims.

A yarn having substantially no twist is schematically illustrated in FIG. 2. Yarns having substantially no twist are occasionally referred to as having manufacturers twist, which expression designates yarns wherein no additional twist to the yarns has been imparted by the manufacturer after their production.

Referring again to FIG. 1 in connection with the method of my invention, there is illustrated the taking ofi of four separate no twist yarns 32a, 32b, 32C, and 32d from the spools housed in respective containers a, 10b, 10c, and 10d. These yarns are passed through four apertures in eyelet guides 12 and 14. It will be noted that the yarns are maintained in spaced parallel relationship by these eyelet guides. Thereafter, the yarns are passed into the bath 18 housed within vessel 16, each such yarn passing beneath guide bar 34, which guide bar is mounted on the inner walls of vessel 16. Three spaced separator plates 36 are mounted on guide bar 34, with the four yarns being separated from one another by the separator plates. This insures that no fouling of the yarns will occur during their immersion in the bath and hence promotes thorough impregnation of each such yarn with the polymeric binder material in the bath.

Thereafter, the yarns are passed out of the bath and through the apertures in eyelet guides 20 and 22. The yarns are then brought together by passage through pigtail guide 24. This serves to collect the yarns and bring them together in parallel relationship.

The four yarns are then passed through tensioning device 26 which serves to regulate and equalize the tensions on the yarns and additionally causes the yarns to be disposed in the form of a band or ribbon, that is, in parallel substantially coplanar alignment.

The four yarns, in such parallel coplanar alignment, are then passed through reciprocating yarn guide 28 and then wrapped about bobbin 30.

I have found it particularly adavntageous to have the reciprocating yarn guide have a channel-like U) cross section, the interior width of the channel substantially approximating the sum of the widths of the four yarns or just slightly in excess of such sum. By virtue of employing such a channelled cross section yarn guide, the yarns are compelled to assume a flat parallel eoplnaar relationship with the edges of each adjacent yarn touching one another.

It is of particular importance to note that, in accordance with the method of my invention, the yarns, after having been impregnated with polymeric binder material, are wound about the bobbin while still wet with the polymerio binder. This insures that upon subsequent drying, a layer of binder impregnated ribbon will be weakly bonded, through the binder, to adjacent layers of ribbon therebeneath and thereabove. Of course, the drying also results in the bonding of adjacent touching edges of the yarns making up the ribbon. Thus, there results a ribbon package that is lirm, tight, holds its form, and is completely resistant to telescoping, sloughing or the like. Yet such ribbon package is such that the outermost ribbon layer may be readily stripped from a ribbon layer therebeneath.

Considering the multitilament yarns employed in making the reinforcing ribbon, it is essential that these iilaments be continuous. The composition of the filaments in the yarns may vary as desired, depending upon the nature and properties desired in the ultimate fabric-reinforced article. Thus, any of the well known continuous filaments, whether synthetic or natural, may be employed, including, by way of example, polyamides, such as polyhexamethylene adipamide and polycaproamide; polyesters, such as ethylene terephthalate polymers and copolymers; acrylic polymers and copolymers such as polyacrylonitrile; vinyl polymers such as polyvinyl alcohol, polyvinyl chloride and polyvinylidene chloride; uon'nated ethylene polymers such as polytetrafluoroethylene and polytriclluoromonochloroethylene; polyhydrocarbons such as linear polypropylene and copolymers of ethylene with other polymerizable monomers; regenerated cellulose; cellulose acetate; polyurethanes; and the like. Also suitable for use in this invention are filament yarns from natural sources, such as silk, glass, and the like.

I have found that a particularly suitable material for the continuous filaments is a biconstituent lilament made up of polyamide and polyester, e.g., nylon-polyester or the like. Such biconstituent filaments are produced commercially, for example, by Allied Chemical under the trade name EF-121." (Frequently such biconstituent filaments of nylon-polyester are referred to as merged filaments?) Generally, these filaments are obtained by the simple expedient of melt mixing polyamide and polyester, e.g., nylon and polyethylene terephthalate, and thereafter extruding the resulting molten mixture in iilamentary form.

Such merged nylon-polyester laments or fibers generally will contain from 30 to 90% by weight of polyester. These biconstituent filaments are more fully described in the Apr. 16, 1966 issue of Chemical Week at page 35. See also Chemical and Engineering News, page 57A, of Sept. 5, 1966i.

In such biconstituent filaments made up of nylon and polyester, either the nylon or the polyester may make up the continuous phase. It appears that for biconstituent filaments `wherein the polyester is at least about 40 percent by weight of the filament, the polyester is the continuous phase, whereas at levels of less than about 40 percent by weight polyester, the nylon is the continuous phase. I have found that particularly advantageous results are obtained utilizing a biconstituent filament of nylon-polyester wherein the nylon is present in about 70 percent by `weight and the polyester is present in about percent by weight.

Inasmuch as the multi-yarn reinforcing ribbon of my invention is to be used for the reinforcement of high pressure rubber hose or like textile-reinforced rubber articles, it is, of course, apparent that the nature of the polymeric binder employed in bath 18 should be such as to promote adhesion as between the ribbon and the subsequently applied rubbery material. Thus, virtually any water-based or organic-solvent based solutioning bath known to the art to be suitable for solutioning cords to promote adhesion of subsequently applied rubber stock can be used as the dipping medium for the yarns and to make the ribbon. Those skilled in the art can readily select a suitable solutioning bath for any given filamentary material utilized in the multi-filament yarns making up the ribbon.

For yarns made up of rayon filaments, nylon filaments, or biconstituent nylon-polyester filaments wherein the nylon is the continuous phase, I have found it particularly advantageous to use, as the solutioning bath, the Well known RFL solutioning bath, i.e., an aqueous resorcinol-formaldehyde rubber latex solutioning material. Examples of such RFL solutioning baths are illustrated in U.S. Pats. 2,128,229; 2,128,635; 2,429,397; 2,561,215; and 2,615,826. See also Rubber World, October 1954, at p. 126, and Rubber World, September 1957, at pp. 847- 851.

Where glass filaments are utilized in making up the yarns, I find it desirable to use solutioning materials known to the art to be particularly suitable for promoting adhesion of rubber to glass fiber, examples being those illustrated in U.S. Pat. 3,029,589.

Where polyester is employed as the filamentary material for the yarns, or where a biconstituent polyamidepolyester iilamentary material is employed with the polyester making up the continuous phase, I have found it particularly advantageous to employ a two-dip solutioning technique, as described in U.S. Pat. 3,533,460.

A preferred method for promoting good adhesion as between a subsequently applied .rubber stock on yarns wherein the multi-filaments therein are made up of polyester Ifilaments or polyester-nylon filaments with the polyester being the continuous phase involves (l) dipping the filaments in an aqueous slurry of a phenol-blocked isocyanate containing dissolved therein water-soluble epoxy resin, drying at about 400 F. for about 2 minutes, and (2) then dipping the dried yarns in an aqueous solution bath comprising resorcinol-formaldehyde resin and a latex of a terpolymer of butadiene, vinyl pyridine, and styrene. This is followed by winding the yarns while still wet about the bobbin to produce a package, and then drying, eg., at about 400 F. For best adhesion, a methylated nitroalkane and a resorcinol-type methylene acceptor should be incorporated in the solid rubber stock that is to be bonded to the foregoing filaments. This system is fully described in Hollatz et al. U.S. Pat. No. 3,503,845.

As already noted, when the band of parallel yarns is subjected to the foregoing twoklip solutioning, the wet band emerging from the second dipping operation is wound on the bobbin while wet and the package thus formed is subsequently dried, so as to realize the advantages of my invention.

It will of course be obvious that known chemical vulcanizing compounds can be added to the solid rubber stock, in every instance, if desired, so as to promote better bonding of the rubber to the multi-yarn ribbon.

After the polymeric binder-impregnated yarns are wound, while still wet with such binder, on the bobbin so as to form a package, the package is subjected to drying. The drying conditions may vary over wide limits; the higher the temperature employed, the less time required. For instance, at a temperature of the order of 400 F. only a few minutes will generally be required, whereas at room temperature a few days may be needed.

An important aspect of this invention is my discovery that the amount of solids pick-up from the bath by the yarns must be appreciably greater than heretofore employed by the art.

As previously noted, in preparing yarns for use in the production of textile-reinforced rubber hose, the prior art has utilized twisted yarns of multi-filament material in treatment with the solutioning bath. Immersion of such twisted yarns in the solutioning bath results in a solids pick-up, on a dry basis, generally of the order of from about 4 to 7 percent by weight. The foregoing range for solids pick-up was in large part due to the geometrical configuration of the yarns. In other wards, the twist imparted to the yarns, resulting in relatively tight yarns of circular cross section, tended to prevent penetration of the solutioning material to the interior of the yarn bundle. Rather, there essentially resulted merely a surface coating by the solids from the solutioning bath. Thus, the prior art had to accept a solids pick up of the order of 4 to 7 percent and further had to accept as adequate the resulting adhesion values as between the so treated yarns and a subsequently applied rubber stock.

By contrast, I have found that by virtue of using yarns of substantially no twist, the amount of solids pick-up from the impregnating bath can and should be at least about 10 percent of the weight of the yarns, expressed on a dry basis. This amount of pick-up is markedly greater than that heretofore contemplated and employed in the art. By utilizing yarns that are of substantially no twist, upon passing these yarns through the impregnating bath (containing the polymeric material that is to promote adhesion as between the yarns and a subsequently applied rubber stock), there results a thorough penetration of the bath to the interior of the yarn with consequent impregnation of each of the individual filaments making up the yarn. Thus, a relatively high pickup, of the order of at least ten percent by weight of the yarn, may be readily attained. And, in contradistinction to the prior art, my polymeric binder material does not merely surface coat the yarns but rather penetrates to all of the interior filaments and impregnates each. This results in considerably improved Vadhesion values as between the multi-yarn ribbon and a subsequently applied rubber stock.

I have found that the amount of polymeric material impregnating the yarns should be, on a dry basis, at least about ten percent by weight of the yarns, desirably from about l0 to 25 percent by weight, and most preferably from about 12 to 15 percent by weight.

In order to readily obtain the foregoing solids pickup, I have found it advantageous to use a solutioning bath wherein the polymeric ybinder material is present in relatively high concentration, e.g., of the order of from about 10 to 40 percent by weight. More preferably, the polymerio binder is present in the bath in a range 0f from about 12 to 25 percent by weight.

As previously pointed out, upon drying of the yarn package while still wet with polymeric binder, the flat multifilament yarn bundles are bonded va the binder to one another at their adjacent edges to form a cohesive ribbon. Such drying also serves to weakly cohere or bond (via the polymeric binder) a given layer of ribbon to adjacent layers of ribbon therebeneath and thereabove.

This results in a rm package capable of holding its dimensional form.

Such a package is illustrated in FIG. 3. This package is tight, completely resistant to telescoping, and yet the free and of the ribbon 38 is readily strippable from. the package for use, as in braiding or spiral wrapping to form a textile reinforcement for a hose or the like. It will be noted that the end of ribbon 3S is shown with the four yarn ends 32a, 32h, 32C, and 32d partly separated. This is merely to identify each yarn as a component of the overall four yarn ribbon. In actual practice the ends are, of course, bonded to one another by the polymeric binder.

It should be noted that the multi-yarn ribbon of this invention may be considered to be substantially rectangular in cross section, with the width being at least twice the thickness, and generally several times the thickness. Typical ribbons for use, e.g. as in the braiding of a textile reinforcement for hose, may be of the order of a thickness of about 0.014 inch and a width of about 0.156 inch, although either larger or smaller ribbons may be prepared and employed, as desired.

My multi-yarn ribbons are also characterized by the fact that the individual yarns making up the ribbon tend to be flattened. That is, they too may be considered to be of substantially rectangular cross section, with the length of the rectangle (or width of the yarn) being in alignment with the width of the ribbon and the height of the rectangle corresponding to the thickness of the ribbon. This tends to further impart a flatness to the overall ribbon. My ability to use relatively flattened (rectangular cross section) yarns arises from the fact that each yarn has substantially no twist, as compared to the twisted yarns used heretofore in the production of high pressure hose, such twisted yarns being essentially circular in cross section.

Neither the number of laments making up the substantially no twist yarns utilized in the preparation of my reinforcing ribbon nor the denier of the multi-filament yarn is critical. Typically the number of filaments per yarn will be from about 50 to 2000, preferably from about 100 to 1000, and most preferably from about 150' to 400. The yarn denier is advantageously from about 1100 to 4400, although higher or lower deniers may also be employed if desired.

The ribbon package of my invention is particularly suited for use in the production of textile reinforced rubber hose or like textile reinforced rubber articles. Thus, as produced, it is heavily impregnated with a polymeric binder capable of promoting adhesion as between the ribbon yarns and a subsequently applied solid rubber.

The manufacture of textile reinforced rubber hose such as high pressure hose is done by conventional methods, apart from the using of my ribbon package rather than yarn packages heretofore used by the art. In this connection, reference may be had to U.S. Pats. 3,083,130; 3,296,047; and 3,336,172; each of which describes in detail conventional methods used in the production of textile reinforced rubber hose. inasmuch as these methods are well known in the art, it is deemed unnecessary to here describe them in detail.

Generally, such methods involve inserting a rubber tubing over a mandrel (this rubber tubing ultimately serving as the interior tubing of the nished hose. Thereafter, a textile reinforcing ply is laid about the rubber tubing, as by the braiding of the yarns over the rubber tubing, spiral wrapping of the yarns, or the likeI In order to produce the hose of my invention there are, of course, employed, instead of the yarns of the prior art, my polymeric binder-impregnated ribbon. The ribbon is desirably braided over the interior rubber tubing, although spiral wrapping or the like could be employed if desired.

It is to be noted that the use of my hat ribbon in braiding a reinforcing hose textile affords particular advantage in that one can obtain a better, closer pack as compared to that obtained from twisted (circular cross section) yarns. Moreover, the ribbon yarns do not separate during the braiding operation.

If but a single ply of textile reinforcement is contemplated for the hose, then over such ply there is disposed a second rubbery tube, and the assembly is then vulcanized by conventional techniques.

Particularly suitable is the lead sheath technique, which technique is well known in the art. Essentially this involves encasing the hose in a lead sheath (formed about the hose by lead extrusion) followed by subjecting the so encased hose to vulcanizing conditions, as by vulcanizing in steam at 60 p.s.i.g. for 60 minutes. Thereafter, the lead sheath is stripped off so as to obtain the vulcanized high pressure textile-reinforced hose.

lf desired, more than one ply of reinforcing textile may be employed. ln such instance, then after the second rubbery tube is disposed over the iirst ply, a second ply of reinforcing textile is disposed over the second rubbery tube, followed by disposing an outer rubbery tube over the second ply. Thereafter, vulcanization is effected as previously described.

Such a two ply textile-reinforced hose is illustrated in FIG. 4, the hose being generally designated by the reference numeral 40. This hose comprises an interior rubbery tube 42, a reinforcing ply 44 disposed thereover, a second rubbery tube 46 disposed about the reinforcing ply 44, a second reinforcing ply 48 disposed about second rubbery tube 46, and an outer rubbery tube 50 surrounding the second reinforcing ply 48. Each of plies 44 and 48 are made up of braided ribbon 38 (FIG. 3), such ribbon previously having been thoroughly impregnated with polymeric binder. By subjecting the hose to vulcanizing conditions, as by the lead sheatth technique described previously, each rubbery layer 42, 46, 50 is vulcanized to the adjacent polymeric binder and hence is tenaciously secured to its respective adjacent reinforcing ply.

It is to be understood that in certain instances one might wish to provide a hose containing three or more reinforcing plies. In such instance, the foregoing technique would be extended accordingly.

As indicated previously, my ribbon permits the obtaining of a close tight pack in the braiding operation, with the ribbon maintaining its flat rectangular shape in the hose carcass. The braided ribbon presents an essentially regular, even profile, as compared to the irregular profile resulting from braiding with twisted (circular cross section) yarns. Such irregular profile is manifested by the appearance of hills and valleys over the hose carcass. Accordingly, the attaching of couplings to the hose often results in only intermittent contact, with resultant failure by virtue of the hose being pulled out of the coupling. By contrast, the even wrap attained by use of my ribbon permits the maintenance of closer tolerances as between hose and coupling, a greater surface to surface contact as 'between the coupling and the braided fabric, and hence a considerably decreased tendency for the hose to fail by detachment of the coupling therefrom.

It will be readily apparent to those skilled in the art that the ribbon package made in accordance with my invention may be utilized to produce a wide variety of types of high pressure hose as well as other kinds of textilereinforced rubber articles. Hose types include, by way of example, special purpose hose, hydraulic hose, air conditioning hose, tank truck hose, gas and oil hose, LPG hose, air hose, welding hose, acid hose, utility hose, agricultural hose, automotive hose, garden hose, paint and lacquer hose, etc.

The nature of the rubbery stock material used in preparing textile-reinforced hoses and like textile-reinforced articles is not critical. Virtually all of the usual rubbers known in the art, whether natural or synthetic, may be employed, for example, polychloropene, nitrile rubber, SBR, butyl rubber, natural rubber, synthetic natural rubber, ethylene-propylene copolymer rubber, EPDM rubber (ethylene-propylene-diene rubber, also referred to in the art as EPT rubber), polyurethane rubber, chlorosulfonated polyethylene rubber, reclaim rubber, and the like.

It will be understood that the rubber employed in the rubbery stock material may, if desired, be mixed with other components such as, eg., polyvinyl chloride. Thus, such a mixture may comprise a blend of polyvinyl chloride with nitrile rubber, for instance, the commercial product known as OZO (Uniroyal, Inc.).

The following examples will further illustrate my invention. All parts are by weight unless otherwise stated.

EXAMPLE l In this example, the apparatus illustrated in FIG. 1 was employed. Commercial RFL latex solution (40% solids, from Versatile Products, Pine Brook, NJ., under the designation Capitol 232 RFL Solution was diluted with water to solids and was employed as such as the bath 18.

Four greige yarn ends, each end made up of 1260 denier, 204 filament, zero twist, nylon-polyester material (EF-l2l, Allied Chemical) were used as yarns 32a, 32b, 32e, and 32d. The yarns were passed through the bath at ambient temperature and at a speed of about 125 feet per minute. Upon emergence from the bath the yarns were gathered and passed through pigtail 24, tensioning device 26, aligned in parallel coplanar touching relationship by yarn guide 28, and wound while wet upon bobbin 30.

The ribbon package was then hot air dried at 225 F. for two hours, followed by cooling to room temperature. The ribbon showed a solids pick up of about 14 percent by weight. The four yarns making up the ribbon were bonded at their adjacent edges to form a flat coplanar ribbon (four yarn ends as one), each such yarn having been thoroughly impregnated throughout its interior. The ribbon package was essentially a unitary, solid, tight mass, with each layer of ribbon being bonded to adjacent layers therebeneath and thereabove, the topmost layer of ribbon being readily strippable from the layers therebeneath.

EXAMPLE 2 Ribbon packages made as described in Example 1 were utilized to make SAE 100R3 hydraulic hose. This is a seamless oil resistant hose made up of an inner polychloroprene tube, a ply of high tenacity flat organic yarn braid, an intermediate polychloroprene layer, a second braided ply, and polychloroprene cover. Polychloroprene tube stock was extruded to size over a flexible plastic mandrel. A standard New England Butt Braider, double deck, 24 spool machine was used to apply both the first and second braided plies. (Twenty-four ribbon packages of the type prepared in Example l where used.) The first ply was braided over the polychloroprene tube, a polychloroprene layer (to size) was placed over the first braid, and the second ply was braided thereover. A polychloroprene cover was extruded to size over the second braid.

Each of the foregoing polychloroprene rubber stocks were, of course, compounded with the usual vulcanizing agents; accelerators, fillers, and plasticizers in accordance with conventional art-recognized recipes.

The uncured hose was then covered with a lead sheath by means of a lead press, and the so encased hose was vulcanized for 45 minutes with 60 p.s.i.g. steam. The lead sheath was then stripped from the hose.

The resultant hose was subjected to quality control testing in accordance with the SAE specification requirements and was found to fully conform thereto. Adherence between the rubber layers and textile plies was outstanding.

Variations can, of course, be made without departing from the spirit of my invention.

Having thus described my invention, what I desire to secure and claim by Letters Patent is:

1. A high pressure hose comprising a cylindrical rubbery interior layer, a cylindrical ply of reinforcing textile ribbon braided fiat around said layer in such a way that the inner surface of said ply is in contact with the outer surface of said layer, and a second cylindrical rubbery layer disposed around and in contact with the outer surface of said ply, said ribbon comprising a plurality of relatively flattened substantially untwisted multi-filament yarns in side-by-side substantially parallel relationship with their adjacent edges touching one another, said yarns being thoroughly impregnated and surface-coated with a polymeric binder in an amount equal to from l0 percent to 25 percent by weight of said yarns on a dry basis and being bonded to one another by said polymeric binder to make up said ribbon, said ribbon being characterized by sufficient flexibility to enable it to be applied around said layer from wound ribbon packages by a braiding operation to form said cylindrical ply, said polymeric binder being capable of promoting adhesion between said yarns and said rubbery layers, said interior and second rubbery layers being vulcanized directly to said binder so that each of said rubbery layers is tenaciously bonded to said cylindrical ply.

2. A hose as defined in claim 1 which has two cylindrical plies of braided reinforcing textile ribbon as defined in said claim, said plies being separated by a cylindrical rubbery layer additional to said cylindrical rubbery interior layer referred to in said claim, and meets the specifications for SAE R3 hydraulic hose.

3. A hose as defined in claim 1 wherein said polymeric binder comprises dried solids deposited from an aqueous resorcinol-formaldehyde rubber latex solutioning material.

4. Hose as defined in claim 1 wherein the amount of said polymeric binder impregnating and coating said yarns is equal to from l2 percent to 15 percent by weight of said yarns on a dry basis.

5. Hose as defined in claim 1 -wherein said multi-filament yarns are formed from nylon.

6. Hose as defined in claim 1 wherein said ribbon was made by impregnating said yarns with an aqueous resorcinol-formaldehyde rubber latex solutioning material, bringing the impregnated yarns together in side-by-side substantially parallel coplanar relationship with their adjacent edges touching, winding the so-impregnated ribbonlike assembly while wet with said solutioning material onto itself into a package to yield a package which contains from 12 percent to 15 percent of solids deposited from said solutioning material, said percentages being by weight of said yarns on a dry basis, and drying said package, and wherein said ribbon was applied around said layer from packages so made.

7. A high pressure hose comprising a cylindrical rubbery interior layer, reinforcing textile comprising a cylindrical ply of reinforcing textile ribbon spirally Wrapped fiat around said layer in such a way that the inner surface of said ply is in contact with the outer surface of said layer, and a second cylindrical rubbery layer disposed around and in contact with the outer surface of said ply, said ribbon comprising a plurality of relatively flattened substantially untwisted multi-filament yarns in side-by-side substantially parallel relationship with their adjacent edges touching one another, said yarns being thoroughly impregnated and surface-coated with a polymeric binder in an amount equal to from 10 percent to 25 percent by weight of said yarns on a dry basis and being bonded to one another by said polymeric binder to make up said ribbon, said ribbon being characterized by sufficient flexibility to enable it to be applied around said layer from wound ribbon packages by a spiral wrapping operation to form said cylindrical ply, said polymeric binder being capable of promoting adhesion between said yarns and said rubbery layers, said interior and second rubbery layers being vulcanized directly to said binder so that each of said rubbery layers is tenaciously bonded to said cylindrical ply.

` References Cited UNITED STATES PATENTS 2,058,778 10/1936 Densmore l6l--C.A,S. 2,291,208 7/1942 Brown et al. 161C.A.S. 2,575,558 11/1951 Newey 13S-RESIN 12 2,899,982 8/1959 Harpfer 138-126X 3,011,525 12/1961 Randle et al. 13S-126 3,060,973 lOl/1962 Mlinar 138-126 3,129,129 4/1964 Schrade et al 13S-123)( ROBERT I. SMITH, Primary Examiner

Images