US 1681745 A
Description (OCR text may contain errors)
Patented Aug. 21., 19298.
EDWARD POHL, OF NEW YORK, N. Y., ASSIGNOR TO NEUTRASOL PRODUCTS CORPORA TION, A. CORPORATION OF DELAWARE.
a broad sense,
COATING roza TEXTILE THREADS.
This invention relates primarily tothe manufacture of artificial silk, the object, in being to produce this material in a form more nearly resembling the natural silk as produced by the worm, than has heretofore been done or been possible to do. The essential and most important mechanical difference between natural silk and artificial silk as heretofore produced, is that natural silk is composed of the silk fibre proper and a gum or wa-x known as sericin, the silk fibre forming the core and the gum an external coating therefor, the latter comprising approximately one-fifth of the total structure of the filament, whereas artificial silk is composed of the cellulose or artificial silk fibre alone, entirely devoid of the gum or Wax layer or coating. It is one object of the present invention to manufacture artificial silk with a coating corresponding to the sericin of natural'silk, having not only similar but other functions which are an improvement upon those of the natural silk coating.
The gum of natural silk serves to reinforce and protect the fibre proper and enables it to resist the strains and chafing incidental to a passage through machinery which converts the silk into fabric. Since this reinforcingelement is absent from artificial silk as heretofore made it has been necessary to make the fibre or thread of a larger or coarser size so that the inherent strength of the fibre or thread itself will be more nearly sufiicient to resist the strains incident to manufacture. But this prohibits the production of fabrics of as fine and beautiful texture as those made of natural silk. An-
- other function performed by the gum is that it binds together the individual filaments composing a thread so that they will notv open in traversing the machinery and subject the individual filaments to breakage, thus making loose ends in the'thread, an excessive amount of which produces fuzzy silk or fabric.
Notwithstanding the fact that artificial silk is ordinarily worked up in coarser threads, or in threads containing a larger number of filaments than natural silk, for the reasons stated, it is still usually neces- Application filed July 27, 1925. Serial No. 46,486.
sary for the throwster, weaver or knitter who obtains the raw yarn from the artificial silk manufacturer, to apply some kind of SlZlIlg or gum material, to the raw yarn before attempting to convert it into a fabric, and thus, in a manner, give it the character of raw natural silk. The application of these sizings or gums hasbeen made in either of two ways, first by dipping the skeins of raw silk in a sizing solution, extracting the excess solution and then drying the skeins before using, and second by slashing'which consists in applying the sizing simultaneously to a number of individual threads running from one beam of a warp, then passing the threads slowly across the surface of a polished hot plate or over rollers to smooth and dry the sizing on the threads, and finally winding them on the second warp beam.
Both of these methods are unsatisfacto because the skein sizing results in matted threads difficult to unwind, while the high heat employed in the slashing. injures the silk and the process is more all sizing materials yet produced for use in either methodhave been lacking in some quality desirable in a good sizing.
All gums and sizings must be capable of removal from the silk after the fabric is made. so that the latter will take the dye and disclose the natural beauty of the silk. This is usually accomplished in the boiloff when all foreign substances such as oil, dirt and the sizing are removed by boiling the fabric in soapy water, a process which is especially injuriousv to artificial silk.
My invention contemplates the application of the reinforcing material to the artificial silk preferably by the manufacturer of the silk, so that when he delivers the silk to the throwster, weaver, knitter or other converter into fabric, it will be a completed very slow. Furthersolidify, or set added a small quantity of oil.
or extra cost of the materials or process might easily render them prohibitive from a commercial standpoint.
v To this end the sizing should be of such a character that immediately after it is deposited uopn the thread it will congeal,
ately wound into a skein, bobbin or other compact body without liability of the adjoining threads of such a compact body sticking together.
A good sizing or coating for the fibre should add to its strength, should bind the individual fibres of a thread together and prevent opening in the loom or elsewhere, should add to the elasticity of the thread, prevent the development of static electricity and afford good lubrication to promote the free movement of the thread when travelling in contact with parts of the machine by which it is beins. converted into a fabric: it should furthermore be capable of,easy removal from the fabric after its function is fulfilled, without injury to the fibre. Such a coating should also be proof against changes of climate or temperature and from varying atmospheric moisture conditions, or mere lapse of time.
To these ends the material I have in vented for coating the fibre consists of a compound of waxes, one of which. preferably is beeswax, this compound being treated in a manner to render it soluble in water of certain temperature, and to which is As a concrete formula which will serve the purpose very well, I cite the following :-3 parts of beeswax, 3 parts of Japan wax, 3 parts of stearic acid and one part oleic acid or red oil. These materials are placed in a melting pot and reduced to fluidity by heat, whereupon they are thoroughly agitated until most finely and intimately mixed. I then dissolve one part of commercial dry caustic soda in 20 parts of water and thoroughly mix this solution with the wax and oil compound. This causes the complete saponification of the Japan wax, stearic acid and oil and the partial, if not complete saponification of the beeswax. On allowing the mass to cool it becomes solid, in which condition it remains until wanted for use. It is a characteristic of this material that while it is in fluid condition it persists as a stable emulsion until it solidifies, i. e. the ingredients do not separate while cooling.
The mode of application to the artificial silk thread or other fibre is to first reduce the solid material to fluid form by heat. This requires a temperature of approximately 100 deg. F. above ordinary room temperature, but the actual worklng temperature of the material is dependent somewhat upon the thickness of the coating it is desired to deposit on the thread. The
so that it can be immedients of the material will be evenly applied to the thread in any liquid form in which they may be used. The essential characteristic of the material is, however, that its melting temperature or the temperature at which it is applied to the textile fibre is considerably above ordinary room temperatures; so that when applied in liquid form in a thin film, contrastin temperature, when immediately thereafter exposed to room or specially pro,-
vided low temperature, will be suflicient to cause the immediate solidifying or setting of the film on the thread. The congealing is so rapid in fact, that when it is applied to a thread while running upwards of 1500 feet per minute, the thread can be wound directly upon a reel located a few inches only from the point of application of the material to the thread, without any stickiness or adhesion of adjoining threads in the finished treated skein on the reel.
This feature renders the material commercially' practicable for the manufacture of artificial silk, because he can make the coating process a part of, or a continuation of, the process of manufacturing the cellu lose into fibre and thread, which involves a lineal movement of the fibres and thread at a very high speed from the moment the paste is exuded from the dies. The coating material can obviously be applied to the silk as an independent process at any time afterthe yarn has been made, either by the manufacturer of the silk yarn, or by the one who makes the yarn into fabric. The mechanical means for-applying the material to the linearly running thread is not an essential part of my invention, since any known device such as a roller rotating par tially submerged in a body of the hot material, may be utilized by leading the thread across and in contact with the roller and thence immediately to a reel upon which it is wound as a finished thread. The nature of the coating material is also such that it can be applied to a thread or yarn while in skein form by adopting special apparatus and methods for that purpose. it were necessary to move the thread slowly in its passage from the applying devices to the reel, or'to allow the thread to travel a long distance before winding it upon the reel in order to give the applied film time to solidify or set before it was wound up, the commercial practicability of the treatment would be much lessened and this is one to the thread, the
of the'objections to the sizings heretofore used.
' for it not only affords the characteristics of.
a good coating as heretofore enumerated, but it prevents the coating from being affected by changes of temperature and moisture conditions so that it will not experience physical change in any climate or locality before the silk is used. For instance a moist atmosphere will not make the coating soft and sticky because water has no effect on beeswax, nor will the highest temperature of the torrid zone soften the sizing because heat below approximately 150 deg. F. has no effect on beeswax. The quantity of beeswax in the compound is or should be sufiicient to prevent the coating as a whole from yielding to any moisture or heat condition which it would ordinarily en-.
counter notwithstanding that the other waxes alone might not be immune from their attack. Japan wax, among other things, is used to furnish a certain amount of stickiness to bind the fibres of a thread togetherand stearic acid affords and imparts elasticity to the treated thread, while the oil ensures no brittleness of the coating at any time. A characteristic of-this compound is that when in its hot fluid condition it s very penetrative and sticky, so that at the moment it touches the thread in this condition it enters the pores of the fibres and into the interstices of the thread and upon immediately solidifying thereafter, it becomes firmly anchored to the thread and presents a firm non-sticky and smooth surface coating thereon.
The objection to the use of beeswax ordinarily as a coating for silk is that it cannot be completely removed from the thread by any practical means after it has served its purpose as a fibre coating. Beeswax is not sufliciently saponifiable to be fully dissolved by any ordinary agent, but my invention provides forthe intimate association of the wax with other waxes or materials,
' which are easily saponifiable and are in a saponified condition by reason of the action thereupon of the caustic soda, so that upon subjecting the treated thread to a. hot Water bath the coatin is converted into an emulsion in which t e fine particles of beeswax are suspended, the bulk of the emulsion being taken from the silk or fibre by the water and the remainder being carried away by one or more subsequent rinsings. This operation is most effectively and rapidly performed'in waterat 160 deg. F. or over. 'The naked fibre is thus left clean for dyeing without the necessity of any injurious treatment such as hard boiling.
' This coating material is applicable to both natural and artificial silk and fact. to anv textile fibre or yarn and can be applied by any desired means. It is also an improvement on natural sericin since the latter varies in quality and quantity with the" health of the silk worm and the quality of the mulberry leaf on whichit feeds, whereas the coating described herein can always be. made uniform in quality and applied in a uniform controlled thickness to the thread. F urthermore on account of its oil content it will not become hard or brittle whereas natural sericin is often found in one or the other of these conditions in which it is far less effective in performing its functions.
It has been pointed out that the material I have herein described is not a mere sizing of the character commonly used to fortify artificial silk yarn such as starch, gelatin, glues and so forth, which are sensitive to moisture and weather conditions and thus lose their efficiency but is probably as near a synthetic sericin as can be produced, judging by its functions and performance. Natural sericin cannot be mechanically removed from the fibre, as by scraping the yarn with the finger nail or across the edge of a knife and this is true also of the coating which is the subject of this application; whereas any of the ordinary sizings can be easily scraped from the thread and are not in any sense an integral part of the thread or fibre. lose fibre or thread, now known as artificial silk, is provided with a coating of the material I have invented, it becomes a perfected and complete artificial silk fibre or thread oorres onding in structure throughout to the structure of raw natural silk.
I claim? 0 1. A coating for textile thread comprising beeswax and a saponified wax intimately mixed therewith.
2. A textile fibre or thread having a coating comprising finely divided beeswax intimatel mixed with a saponified wax.
3. X textile fibre or thread having a coating comprising finely divided beeswax intimately mixed with a. saponlfied wax and saponified stearic acid.
4. A textile fibre or thread having a coating comprising the reaction product of wax, stearic acid and oleic acid with. a saponifying agent.
5. A textile fibre or thread having a coating comprising finely divided beeswax 1n t1- mately mixed with saponified stearic acid.
6. A textile fibre or thread having a coating comprising finely divided and partially saponified wax intimately mixed with a ful y saponified wax.
' 'l. A textile thread having a coating comprising the reaction product of a plurality of waxes, one of which is beeswax, with a saponifying agent. I
. 8. A coating for textile threads compris- Therefore when the naked celluing the reaction product of beeswax, Japan wax and stearic acid with a saponifying agent. v
9. A coating for textile thread comprising the reaction product of beeswax, Japan wax, stearic acid and oleic acid with a saponifying agent.
10. A coating for textile thread comprising the reaction product of substantially 10 three parts of beeswax, 3 parts ofJapan Wax, 3% parts stearic acid, 1 part oleic acid and 20 parts of water with a saponifying agent.
11. A coating for textile thread comprising a plurality of saponified waxes and saponified oleic acid to prevent the coating from becoming brittle.
In witness whereof,
I hereunto subscribe