Low Fuming Spin Finish For Nylon Weaving Yarns

Abstract

A lubricating composition useful in the processing of nylon yarns consisting of 30 to 50 percent vegetable oils and trimethylolalkane esters of fatty acids having 8 to 10 carbon atoms, 10 to 30 percent imidazolinium alkyl sulfates, and 20 to 60 percent of an emulsifier selected from a group consisting of alkoxylated fatty acid esters of sorbitan and sorbitol and alkoxylated alkyl phenols.

Description

The present invention relates to textile lubricating compositions that resist degradation and fuming in high temperature applications to nylon fibers and which will not adversely affect the application of polyacrylic acid size overcoatings applied thereafter.

In the preparation of yarns suitable for textile manufacture it is necessary to apply a lubricant to the filaments to permit processing of the yarn with minimum difficulty. As is well known in the art, selection of a suitable lubricant composition is not readily made since many diverse requirements are imposed on the lubricant composition by the nature of a yarn's end use and the manner in which it is manufactured. Of particular concern in high temperature processing is the formation of hard insoluble resins and the fuming of the finish when contacting heated surfaces. Usually these surfaces are heated above the boiling point of water which is a major solvent for many spin compositions and can be evaporated without causing health problems in the atmosphere surrounding the processing equipment. However, most compositions either because they degrade or because they contain violatile components form noxious vapors which are irritating to those working in and around such equipment.

Previously the use of high temperature spin finishes required an additional washing step to remove them from the fiber prior to the application of polyacrylic acid sizes because they were not compatible with the finish coating.

The novel spin finishes of the present invention, therefore, solves environmental problems as well as the problem of compatability with polyacrylic acid sizes applied to the yarns.

It is the primary objective of this invention to provide a textile spin finish composition suitable for use in the preparation of nylon yarns employing high temperature processes and which are subsequently treated with polyacrylic acid type sizes.

Another object is to provide nylon yarns having a lubricant finish and a polyacrylic acid size overfilm.

These and other apparent objects are obtained in accordance with the invention by the application to the nylon filament of an aqueous composition containing about 1 to 35 percent of a spin finish consisting essentially of 30 to 50 percent by weight of a lubricant selected from soybean oil, coconut oil or 1,1,1-trimethylol alkane triesters of fatty acids having 8 to 10 carbon atoms; 10 to 30 percent of 1-hydroxyethyl-2-heptadecenyl-imidazoline as an antistatic agent; and 20 to 60 percent weight of one or more of the following emulsifiers: polyoxyethylene (20)sorbitan monolaurate, polyoxyethylene(8)nonylphenol, and a surfactant made by condensing 40 mols of ethyleneoxide with a mol of sorbitol hexaoleate containing 15 percent by weight water.

In the conventional manufacture of yarn from polyhexamethylene adipamide, polycaproamide or other known nylon compositions primarily designed as weaving yarns, the nylon yarn comes into contact with a plurality of heated rolls. In one typical process, nylon polymer is melt spun and the resulting filament strands are passed around a roll having at least one surface immersed in a bath of lubricating finish. Strands leaving the finished roll are converged by means of a guide. The yarn is then fed by a feed roll to a draw pin and then to first stage draw rolls. In this step, part of the total drawing that is to occur is applied. The yarn then passes over a heated tube and from there to a second stage draw roll where the remainder of the draw is imparted. The drawn yarn is then wound in the conventional manner. The heated tube referred to can serve to preheat the yarn as it passes over second stage draw rolls. A typical hot tube temperature is in the range of about 185.degree. to 190.degree.C. The second stage draw rolls are heated to about 225.degree.C. This temperature serves to volatilize part of the finish that is present on the yarn and aggravates oxidizing conditions, resulting in gum or resin formation. During this operation, the decomposition of the finish ingredients fill the atmosphere around the draw and spin equipment and serve as serious irritants to the operators thereof. In using the finish composition of the present invention the down-time of equipment is substantially reduced thereby increasing the efficiency of the operation and the personnel required to operate it.

Prior to weaving nylon fabrics, a film forming material called a size is applied to both spun and filament yarns in an operation called slashing in order to strengthen and protect these yarns from the abrasive action of the weaving process. While starch and gellatin based sizes have been used for many years on regenerated cellulose and acetate yarns, these sizing materials do not function properly on nylon yarns due to a combination of poor yarn wetting properties and a lack of adequate adhesion between the size and the yarn. In addition, many spin finish systems employed to insure proper spinning, drawing, and packaging of the yarn interfere subsequently with the proper adhesion of the size to the yarn.

Polyacrylic acid sizes have been developed which offer excellent adhesive properties suitable for nylon yarn applications due mainly to the formation of a chemical bond between carboxyl groups in polyacrylic acid and the amido groups in nylon. Several manufacturers produce a complete line of polyacrylic acids sizes which vary in their molecular weight and/or in the use of copolymers or additives. Sizes have been developed for specific nylon fiber applications such as low molecular weight polymer (5,000 - 50,000) for easy penetration in the large fiber bundles versus high molecular weight materials (50,000 - 250,000) for application to fine denier nylons. Such materials are available as aqueous solutions and are sold by B. F. Goodrich Chemical Co. as Good-rite K-702, K-732, and K-714; by Rohm and Haas Co. as Acrysol A-1, A-3; and by Polymer Industries, Inc. as Polyfilm 236 to name a few. Sized yarns usually have coating of polyacrylic acid ranging from 0.5 - 2 percent by weight of the yarn.

Prior art spin finishes such as those described in U.S. Pat. Nos. 3,464,922; 3,402,127; 3,575,856; 3,338,830; 3,428,560; 3,421,935, usually contain a combination of ingredients which function as the lubricant, antistat and emulsifier. These are deficient for the above described purposes either because they are incompatible with the polyacrylic acids size, they do not function properly as a lubricant at high temperatures or that they produce excessive fuming.

The compositions of the present invention are prepared by mixing the components to produce a homogeneous solution. Each of the components employed is commercially available and can be used in this invention as obtained without special treatment. For example, any commercially available vegetable oil such as soybean oil and coconut oil or tri-fatty acid esters such as caprylic, pelargonic, capric and mixtures thereof of 1,1,1-trimethylolethane or trimethylol propane can be mixed with commercially available antistats such as diethyl sulfate quaternary of 1-hydroxyethyl-2-heptadecenylimidazoline and thereafter with 20 to 60 percent of one or more of the following emulsifiers such as polyoxyethylene(20)sorbitan monolaurate, polyoxyethylene(40)sorbitol hexaoleate, and polyoxyethylene(8)-nonylphenol.

The finish is usually applied to the nylon yarn filament in amounts from 0.5 to about 1.5 percent by weight of the yarn as aqueous solutions containing 98 percent to about 65 percent water.

There are various methods for applying the finish to the yarn. In one method the yarn passes in contact with a roller or wick partially immersed in the aqueous finish compositions. The other finish application methods consists of spraying, brushing or immersing the yarn in aqueous finish composition baths such as described in the spinning and drawing steps above.

Preferred finishes are formed by blending 40 to 60 percent trimethylolethane tripelargonate, 20 to 35 percent polyoxyethylene(8)nonylphenol and 20 to 30 percent diethylsulfate quarternary of 1-hydroxyethyl-2-heptadecenyl imadazoline.

SIZE-SPIN COMPATABILITY TEST

A quick method has been devised for demonstrating the compatability of polyacrylic acids sizes with spin finish compositions. Such a test circumvents the longer procedure needed for coating nylon yarns with finish and acrylic acid size compositions to demonstrate compatability. The test is carried out by preparing a size bath heated to 55.degree.C. and thereafter adding 2 percent by weight of a finish composition to be tested. In the instant test, 2 baths were prepared one containing 6.25 percent by weight of POLYFILM 236 and the other 6.25 percent solids of ACRYSOL A-3 both being polyacrylic acid sizes manufactured by Polymer Industries, Inc. and Rohm & Haas, respectively. These two sizes are considered representative of the range of products commercially available. After a five minute period of storage, the size/finish systems are checked for compatability and any system that exhibits gross separation is considered incompatible. If compatible, they are then cast onto a TEFLON surface and dried in an oven at 70.degree.C. and the films that result are evaluated. The finish is considered compatible with the size if the films are non-tacky and similar in appearance to those films cast from the size alone.

Nylon yarns and filaments having first been coated with the spin finishes of the present invention are therefore compatible with polyacrylic acid sizes readily commercially available by the definition imparted by the above test. The test results further indicate that when nylon is treated first with the spin finish and thereafter with polyacrylic acid sizes that the size will function as designed and will not suffer any loss in performance due to spin finish incompatability problems.

The following example is presented to illustrate a preferred composition of the invention but it is not intended to limit the scope of the invention or its application.

EXAMPLE 1

A preferred spin finish is prepared by mixing the following components:

Component % By Weight ______________________________________ 1,1,1-trimethylolethane 50% tripelargonate polyoxyethylene(8)nonylphenol 25% diethylsulfate quarternary of 1-hydroxyethyl-2-heptadecenyl- imidazoline 25% ______________________________________

The mix is then added to water and heated to about 50.degree.C. to form an aqueous solution containing 85 percent water. The spin finish requires no homogenization to form a stable emulsion.

The aqueous finish composition is then applied to a melt spun 185 denier/34 filament nylon 66 yarn at a point between the spinerette and the bobbin used to take up the filaments. The yarn is thus coated with 1 percent finish based on the yarn weight. These filaments are then drawn on a conventional draw-winding machine employing two sets of rolls; a draw-pin between said rolls, around which the yarn is snug and thereafter into a takeup assembly in which the yarn is wound on a cheese. Utilizing conventional procedures, the yarn is then wound onto a beam and subsequently, the sheet of yarns from the beam is passed through a slasher where the sizing material such as Acrysol A3 is applied in aqueous solutions.

The finish-polyacrylic size coated nylon upon examination exhibited no tackiness or clouding of the surface. No noticeable separation occurred in the size bath as the finished nylon passed through it.

The slashed yarn is then ready for weaving. The yarn exhibits very good lubricity, excellent bundle cohesion and good antistatic properties during the weaving operation.

EXAMPLE 2

A spin finish is prepared by mixing the following components:

Component % By Weight ______________________________________ Trimethylolethane tri-C.sub.8.sub.-10 40% fatty acid ester Polyoxyethylene(8)nonylphenol 30% Diethylsulfate quarternary of 30% 1-hydroxyethyl-2-heptadecenyl- imidazoline ______________________________________

Nylon fibers can be processed in a manner similar to Example 1 and sized with several polyacrylic acid solutions having molecular weights ranging in 5,000 - 10,000; less than 50,000; less than 150,000; and 180,000 - 220,000 to give coating weights of 0.5 - 2 percent by weight of the yarn. The yarns can be woven by many techniques without abnormal difficulty.

Claims

What is claimed is:

1. A nylon spin finish composition which is compatible with polyacrylic acid size applied therewith consisting essentially of:

a. 30-50 percent of lubricant selected from the group consisting of soybean oil, coconut oil, triesters of fatty acids having 8 to 10 carbon atoms of 1,1,1-trimethylolethane and 1,1,1-trimethylolpropane;

b. 10-30 percent by weight of diethyl sulfate quarternary of 1-hydroxy ethyl-2-heptadecenyl-imidazoline;

c. 20-60 percent by weight of an emulsifier selected from the group consisting of polyoxyethylene (20)sorbitan monolaurate, polyoxyethylene(8) nonylphenol and polyoxyethylene(40)sorbitol hexaoleate.

2. A composition of claim 1 consisting essentially of 50 percent by weight trimethylol ethane tripelargonate; 25 percent polyoxyethylene(8)nonylphenol and 25 percent by weight diethylsulfate quarternary of 1-hydroxyethyl-2-heptadecenyl imidazoline.

3. A composition of claim 1 consisting essentially of 40 percent by weight trimethylolethane tripelargonate; 30 percent by weight polyoxyethylene(8)nonylphenol and 30 percent by weight diethyl sulfate quarternary of 1-hydroxyethyl-2-heptadecenyl imidazoline.

4. An aqueous emulsion of the compositions of claim 1 containing 97-65 percent water.