US1999170A - Dyeing process for solidified drying oils - Google Patents

Description

Patented Apr. 23, 1935 PATENT OFFICE DYEING rnocnss FOR soumrmn name oms Vernon a. Pallas, Cortland, N.

No Drawing. Original application November 8,

1932, Serial No. 641,739. Divided and this application November 5, 1934, Serial No. 751,545

9 Claims. (Cl. 91-68) This invention relates to a novel process for dyeing and similarly treating fibriform substances such as threads, strands or braided cords, also 'textile products of silk, linen, cotton, viscose rayon or the like after they have been coated with a solidified drying oil, and which process is especially suited for the economical production of high grade fish lines and oil coated fabrics.

The present methodis a division of my copending application, Serial No. 641,739 filed November 8, 1932, as now confined to an intensive heat treating process for baking drying oils upon fibrous materials. Since certain aspects of the resulting product bear upon the dyeing problem herein solved, a brief definition of the aforesaid so-called drying process will serve to characterize the preferred preparation to be given such oil coated materials for subsequent. dye treatment in an improved manner.

Said drying process has more specifically to do with impregnating a fibrous substance with filler dope and then baking at a controlled oven temperature ranging between 100 C. and 200 C. to solidify the applied drying oil in an oxidizing atmosphere. Several oil coatings or layer courses may be superimposed thereon to build up a pliant, homogeneous filler body about the fibrous strand. Each of the respective coatings may be subjected to a separate baking period but the total time of heat application is preferably terminated in order to preserve the oil coated fibrous material against inordinate deterioration in tensile strength while exposed to such intensive heat treatment. The stipulated temperature range makes for a tough solidified oil coating that may be rapidly and thoroughly oxidized without resort to chemical driers. My filler dope is purposely kept substantially free from pigments or other detrimental coloring agencies likely to addition- 40 ally weaken the tensile strength of the fibrous material by chemical reaction or to otherwise injure the quality of its solidified coating while being subjected to the prescribed relatively high baking temperature for a prolonged period. By virtue of a final seasoning bake applied prior to coloring the solidified oil body, my coating is made to withstand aging without significant hardening or checking. Such supplemental baking improves the kink resisting qualities of the 50 finished product.

The object of the present invention is to devise a dyeing method that will allow of imparting color to a solidified, translucent drying oil particularly when the filler is applied and baked upon a fibrous core strand in accordance with my improved heat treating process; also to attain a uniform color distribution along such strand by dyeing inwardly from its. coating exterior without allowing the core strand to become fully saturated and thereby overcome certain intrinsic 5 coloring difficulties heretofore encountered in the fabrication of superior fish llnes,'textlles or the like oil coated goods on a rapid productive spale.

A further objective is to provide for a durable but pliant solidified oil coating that shall prove suit- 10 able for fish line or fabric purposes and by the application of the cited'seasoning bake, additionally toughen my solidified coating and render it more resistant when subjected to a kinkproofing test.

'It has heretofore proven difficult to dominate 15 the natural yellow color common to most drying oils without mixing a pigment into the filler dope bath, but which obstacle may be surmounted by a procedure that will hereinafter be more fully defined. As directed to the fabrication of a fish line 20 or the like product, the usual braided line strand thereof primarily consists of silk material that may be kept white or undyed. Such virgin line may be impregnated with a filler dope composed in any constituent proportions of suitable raw or treated drying oils, preferably without the presence of lead, manganese or the like chemical driers, also free from pigments or the like injurious contamination likely to combine chemically with the fibrous strand or its coating and thereby adversely afiect the product while undergoing intensive heat treatment.

The resulting body of solidified oil remains translucent whether or not the line strand has been initially dyed or otherwise stained. It is preferred to introduce any other coloring matter as an ultimate step, that is to say, after all coating operations have been completed. A filler dope of the same character is also applicable to fabrics or the like textiles.

In conjunction with the dyeing of my oil coated product, it is preferred to include a seasoning step in my heat treatment during which the oil coated line or fabric is exposed to a prolonged final bake of from one to three hours at a comparatively high temperature preferably ranging from 140 to. 150 C. Such supplementary baking serves to more thoroughly complete oxidation without inordinately weakening the fibrous filament, hence fortifies my translucent fiber coating in withstanding a kinking test so that upon being superficially dyed, said coating will not develop a conspicuous localized opaqueness when subjected to such strain.

Exposure to high temperature generally causes the undyed oil filler of an initially light yellow shade to become darker in color during protracted baking. Where a pale or other attractive light finish is desired, I have found it expedient to first bleach or fade such product after prolonged baking, preferably but not necessarily, by light ray treatment as distinguished from chemical bleaching. The surface of the solidified oil coating may be exposed to strong sunlight or ultraviolet rays of ample intensity until a desired lighter color shade has been achieved. Such processing may be conducted simultaneously with one or more of the cited baking steps. Thereupon, said bleached product may be immersed in a suitable dye bath containing soluble, organic dyestuif or the equivalent thereof; Glaubers salts or other aiding chemicals may be used to stimulate the dyeing process. Because of its being virtually impervious to water and other dyestuff carriers, a solidified drying oil usually requires a concentrated dye solution to bring the time of color absorption within reasonable operative limits.

After taking on the desired color shade and the coatings have become superficially impregnated with coloring matter, the removed product may be subjected to a dye precipitating agency such as a solution of barium chloride or the like chemical. This step fixes said dye and makes it insoluble in water-to provide for an adequately waterproofed and non-leaching finished product.

The aforesaid dyestuff naturally penetrates rather slowly into the surface of an impervious oil coating of this kind, and hence the coloring agent will be rather gradually absorbed even should the impregnation be accelerated by means of hydrostatic pressure. In practice, it has proven exacting to effect an even distribution of the dye throughout the length of a fish line or the like textiles, since the thickness of the applied baked coatings are likely to vary somewhat about the irregular surface contour afforded by the braided or twisted core strand thereof. Furthermore, after some of the thinner coating spots have been penetrated, the greater dye afiinity of the fibrous core material tends to bring about an uneven color apportionment. In order to attain a shade that shall appear substantially uniform throughout the baked translucent drying oil, it is preferred to cease dyeing operations prior to complete impregnation of the core material. This mode of processing is likely to leave a stratum of undyed or innate yellow filler lying immediately contiguous to depressed portions of the aforesaid irregular core surface. A silk fish line in which the solidified filler surface rather than the braided strand has thus been intensely stained, makes for a superior commercial product and one in which both the time and cost of dyeing may be materially reduced. Where the translucent oil coat ing of such goods has been dyed inwardly, any pronounced change in its refractive index under a sharp kinking test or the like spotty surface imperfection may be substantially overcome by my improved coloring process as used in combination with the prescribed seasoning heat treatment.

It may in certain instances, prove expedient to work with an initially dyed filament which of itself would virtually impart color to the translucent coating baked therearound. It is generally preferred however, to superficially dye the innate pale color of such coating to a darker shade and thereby subdue its contrasting yellow streak so that the baked filler medium may be sharply kinked without vitiating the natural transparency thereof.

The foregoing is descriptive of a method that has been found wholly'satisfactory as applied to apparent that certain of the cited steps may be omitted and that their described order may be rearranged. For instance, if the ultimate surface finish of such product is to be kept relatively dark in color, it may prove needless to bleach the same, particularly so if oven temperatures lower than 100 C. should be resorted to. As regards the use of the precipitating or dye fixing agency, this is primarily intended to produce a water fast article that will also prove reasonably color fast when exposed to sunlight. Where waterfastness is not a requirement, the cited dye precipitating step may be eliminated. As a substitute for the described coloring and dye precipitating process, the final surface of the coated line or fabric may likewise be stained and made waterfast in a bath of mineral oil or other dye carryi g agency that is colored with an oil soluble dyestuif.

A fish line made in accordance with my process not only handles well and remains soft and pliable, but to a marked degree solves the cited kinking problem. This end is preferably secured by working with a filler medium which may be kept substantially pure throughout the heat processing steps and allowing no pigments or the like impurities to be introduced which under intensive heat treatment, may tend to set up detrimental secondary chemical reactions. Said dyeing process also is admirably suited to treat cloth or other woven goods of suitable texture which may likewise be impregnated and baked to make up table covers, window shades, raincoats, umbrella covers, and the like moderately waterproofed sheet materials. In such instances, the cited filler bleaching step assumes especial importance in that it allows of finishing such goods in many handsome colors of lighter shade.

I claim as my invention:

1. The process for dyeing an oil coated fibrous filament and which process comprises coating said filament with drying oil and solidifying said coating in an oxidizing atmosphere, and then superficially coloring said coating with dyestufl and terminating the dye penetration prior to allowing the filament to become saturated.

2. The process for dyeing an oil coated fibrous filament and which process comprises coating said filament with drying oil substantially free from a pigment and baking in an oxidizing atmosphere at a temperature ranging between one hundred and two hundred degrees centigrade for a limited period of time that is terminated in accordance with the actual baking temperature employed to preserve the filament against inordinate deterioration while solidifying the oil coating thereof, and then superficially applying dyestuff to said coatingwithout allowing the dyestufi to saturate the filament.

v 3. The process for dyeing an oil coated fibrous filament and which process consists in applying a series of drying oil coatings uponsaid filament and baking the respective coatings for a length of time sufiicient to solidify the drying oil and 4. The process for dyeing a fish line and which process comprises coating the line strand with drying oil and baking in an oxidizing atmosphere at a temperature ranging between one hundred and two hundred degrees centigradefor a limited period of time that is terminated in accordance with the actual baking temperature employed to preserve said strand against inordinate deterioration while solidifying the oil coating thereof, then superficially treating the baked coating with dyestuff and thereupon fixing the penetrated dye to render the same substantially insoluble in water.

5. The process for dyeing an oil coated fibrous filament and which process consists in coating said filament with an innate pale drying oil, baking in an oxidizing atmosphere for a prolonged period of time sufficient to solidify the coating of drying oil and darken the shade thereof and which baking is terminated in accordance with the actual baking temperature employed to preserve the embraced filament against inordinate deterioration while being baked, then bleaching said darkened oil coating to a lighter shade, and thereupon dyeing the bleached oil coating to a different color. 1

6. The process for kinkproofing a colored fish line and which process consists in initially coloring the line strand, then coating said strand with drying oil kept substantially free from a pigment, and lastly baking the coated strand in an oxidizing atmosphere to dry the oil into a solidified translucent state and which baking includes a seasoning period held at a temperature ranging between one hundred. and two hundred degrees centigrade without allowing the tensile strength of the strand material to become unduly impaired during such seasoning period, said seasoning serving to convert the drying oil into a pliant body that substantially maintains its translucency and correspondingly shows the outline oi! the strand therethrough when subjected to a localized kinking strain.

'7. The process for dyeing an oil coated fibrous filament and which process consists in coating said filament with drying oil that is kept substantially free from impurities likely to react injuriously upon said oil when subjected to heat treatment, then baking the coated filament for a limited period in an oxidizing atmosphere at a temperature ranging between one hundred and two hundred degrees centigrade to solidify and season the oil coating, and thereupon superficially treating the seasoned coating with a carrying agency containing dyestufi.

8. The process for dyeing an oil coated fibrous filament and which process consists in coating an initially colored filament with semi-transparent drying oil of an innate pale color and baking the filament in an oxidizing atmosphere to solidify the coating thereof, then superficially treating said coating with dyestufl of a shade darker than the aforesaid innate color to render the baked coating relatively less transparent and thereby correspondingly mask the colored filament.

9. The process for dyeing a fish line and which process consists in coating the line strand with a translucent drying oil having an innate pale color and baking said strand in an oxidizing atmosphere for a limited period to solidify the coating thereof, and then superficially treating said coating with a carrying agency containing dyestufi to impart color thereto of a shade darker than the aforesaid innate color but without allowing the dye to saturate the line strand.

VmNON R. PALLAS.