US2428046A - Artificial filaments - Google Patents

Description

Sept. 30, 1947 W. A. SISSON ETAL ARTIFICIAL FILAMENTS Filed Aug. 5, 1943 WW T58 w wz WWW mw w z. 9

ATTORNEY.

Patented Sepn 399 i? Webb, Glen ltre, Fa.

itt, Serial No. tt'hio ilpplioation 8 t z i This invention relates to fil 'i 1.1., oi com-- posite character comprising at least two basic components, one of which is disposed between two portions oi the other or others which may cover the lateral surfaces of the former component completely or only partially. In the iormer case, a core or sheath arrangement is obtained, while in the other, novel eflects may be obed.

It is an object oi this invention to provide fllaments having novel eflects. Further objects and advantages of this invention be apparent irom the drawing and the vdescription thereof hereinafter.,

In the draw illustrative of the invention,

Figura i is a mld-section through an extrusion device for producing fiiaments oi the invention;

Figure 2 is a cross-section taken on line II-H of Figure i;

Figura 3 is a cross-section taken on line m-Illi of Figure i; v

Figure i is a mld-section of another extrusion device ior produe '-z-ents of the invention;

r is a cross-section :tz i' en on e V-V of Flgure t;

Figure o is a cross-section taken on line 'VI-VI of Fe t.

Figure 'i is a cross-section ten on line -VH oi! Figure o;

Fisui'e 8 illustrates in cross-section various of the novel filaments obtainable in accordance with the invention: and

Figura 9 illustrates in cross-section, additional varieties of filaxnents obtainable in accordance with the invention.

As shown in Figures 1 to 3, thespinneret is attacheri to a supply head t ior the sp i. z. w materials or solutions by a coupling i.. A gasket is positioned between the flange of the spinneret 2 and the supply head t to assure a tight seal. Feed pipes and 'i communicate with passages 8 and t respectively. Within the space back of the face of the sp hneret t; there is provided a partitioning mea comprising a plate it from which a plurality of approximately parallel rlbs ii extend toward the back face of the spinneret withoutl being in contact therewith. A partie tion i2 extends from the plate it in the opposite direction to divide the space back of the plate iii into two separate regions A and B communicating with the passases t and t respectively. This partitioning means may be formed integrally within a cylindrical sleeve 93 fitting'within the recess it within the supply head t and resting upon a spacing ring i to support the 2) 2 partitioning system out of contact with the b -iace of the spinneret. The spieret is provided with two rows of oriflces it arrangeo'i in registry with alternate spaces between the ribs ii. 'I'hus as is shown in Fig'ure 3, every other between the partitions ii faces a portion of 'the spinneret face which is looking in orifices, while the intervening spaces between partitions ii are arranged in direct opposition to the spinneret oriices. Passages il through plate it connect the chamber B with the alternate speces ribs ii which face blanh portions ot the spin neret, while passages it coect the chzber i with the other aiteate spaces which .tace the orifices oi the spneret 7 It will appear from a study oi" the arraneenient of Figures i to 3, that ii two difierent spinning materials or solutions are supplied bv pipes t and l, the material or solution immediately bach 2h ot the spinneret tace would 'he more or less 35 seotionssuch as those sho stratiiied into altemating layers of the two types oi spinning materials, one ot the types being found in the spaces between the r'ibs li iacing the spinneret orifices d the other being found in the spaces between ribs ii which tace 'bl spaces ci' the spinneret face. ince both pumps force the spinning materials or solutions to find egress, the material or solution in the spaces between partitions ii which face blanlr ses of the spinneret face must fiow through the spinneret orifices on either side of the spinning material or solution flowing through the spaces between the ribs ii the speret orifices. Such ilow gives rise to el-i.: cross-s i e 8. If the pump associated with pipe i is operated at great volumetric speed than tt connected with pipe the lateral portions of fllament-iorming ma terial completely envelop the central portion as shown in Flgure 8a. When the pump speeds are more nearly equal, a cross-section of iilament sar to Figure 8b is obtained, while if 'the pump associated with pipe l is operated at con" siderably lower volumetric output than t associated with pipe t, the filament structure of Figure tc is obtained. The cross-section can also be controlled by selection of spinning niaterials. For example, in the case of two viscoses, if the intermediate viscose shrinlrs more rapidly in setting up, than the outer visccse, the crosssection of Figure 8a is obtained, whereas a rever-sal of shrinkage characteristics results in the cross-section of Figura 8a. Again, control Vcera be' eflected by aitering both pump speeds and viscose shrinkage characteristics. Although the 3 boundaries between the components of the niaments are shown distinetly in the drawingl there may be some intermingling of the different components on either side of the boundaries.

The extrusion device of this invention may be used for wet or dry spinning or for spinning molten materials. The two spinning materials may be solutions which may contain the same iilament-forming substance in solution but differ in the kind of solvent or the ooncentration of the lilament-forming substance. The spinning materials may be polymeric substances which difl'er in their degree of polymerization or degradation; in the case of cellulose or its derivatives, the two solutions can be produced from celluloses of different origin, for example one from cotton linters and the other from wood pulp. In the case of spinning solutions which undergo a ripening process, such as viscose. difference of degree of ripeness may be the sole difference or one of several ditl'erences (which may include also cellulose content, sodium hydroxide content. carbon disnlfide content) between the spinning solutions.

The two spinmng materials may comprise the same or different spinning substances, but difler in that one of the two contains incorporated therein, either suspended therein or dispersed therein, such as by true or colloidal solution 'or by emulsiiication, at least one substance which is not of itself a filament-forming substance. Alternatively, both spinning materials can contain one or more of such additions in different concentrations. Such additions can be solid, liquid or gaseous, for example pigments, roughening agents, softening agents, agents for improving the feel, fats, oils, soaps, resins, dyestuifs. fungicides, medicinal substances, phosphorescent substances, and substances which can react chemically with the spinning substance in the solution or during the precipitation. In particular, those additions which are used to modify the properties of the fliaments and have hitherto involved unavoidable disadvantages when applied to homogeneous fibers can be restricted to that zone of the fllament where they are desired. For example, pigments and delustrants which are introduced into the spinning mass for the purpose of roughening the surface of the filament, or of coloring or dulling the iilament, cause a sensible decrease in the strength. By the new process such substances, which can fulfill their purpose when disposed only at the surface of the illament, need be introduced only into the spinning material or solution for forming the outer envelope of Figure 8a, while the core remains undiluted by such additions and, therefore, maintains its normal strength.

When the process is carried cut with two spinning solutions which contain different spinning substances in solution, the two spinning substances can be chemically related, as, for example, two different cellulose esters, or a cellulose ester and a cellulose ether, or two different albuminous substances. Two spinning substances may, however, be used which belong to quite different classes of materials, such as cellulose and an albuminous substance, or a cellulose ester or ether and an artiflcial resin or rubber produoed by polymerization. The only lixnitation is that the two spinning materials do not mutually coagulate each other and are coagulatable by a common coagulating medium. According to whether one kind of spinning substance forms the core or intermediate portion and another kind the sheath or lateral portions of the filaments, or

4 i vice versa, fllaments of diiferent properties can be obtained from the same substances. By using two spinning materials which shrink to a different extent during precipitation, drying or aftertreatment, there may be obtained. for example, strongly crimped threads. Also, one or both spinning materials or solutions may consist of or comprise mixtures of two or more fiJament-forming substances insofar as this is permitted by the compatibility of the particular substances.

Various effects may be obtained by enclosing a pigment or dyed core by an uncolored sheath,

or one which is colored but not so deeply as to prevent the core from exerting an influence on the appearance of the nlament. By sandwiching a colorless or lightly colored component between lateral components intensely dyed or heav'lly pigmented to form structures having cross-Sections similar to F'igures 8b and 8c, or by reversing the disposition of the lightly and densely colored components respectively, novel and interesting effects are obtained, and such effects are aecentuated when the two components are made of materials having different shrinkages, and are subsequently diiferentially shrunk to effect crimping thereof.

Further modiflcations may be obtained by changing the partition |2 from a simple transverse rib to a partition of Y-shape, and providing another pipe connection similar to 5 and 'I for supplying a third spinning material or solution to the third chamber thus provided. In that case, the central one of the spaces between the several partitions il may be connected to the third chamber receiving the third spinning material or solution by a suitable passage similar to the central passage il shown in Figure 2. In such an arrangement, the filaments would be composed of three fllament-forming materials arranged similarly to the layers of Figures 8a, 8b and Sc, but with one of the laterally disposed materials of different composition than the other laterai member. This arrangement is illustrated in Figures 9a, 9b, 9c. This arrangement may be of particular advantage to form crimped filaments by associating a plurality of filament-forming materials at least two of which show different shrinkage characteristics, particularly after stretching, and subsequently crimping them by taking advantage of these characteristics.

Figures 'i to 'l' show a modiiication of the extrusiondevice in which the partitioning means within the space back of the spinneret face is arranged to co-operate with a spinneret having concentric groups of oriflces, such as cii'cular rows of oriflces. In this arrangement, the space immediately back of the spinneret face is dividcd by a plurality of concentric partitions 2| (four being shown, though any number may be used) into concentric annular chambers Cl. Ca. Ca and C4 about a central chamber C. These partitions 2| may extend from a transverse plate 22 secured in or integrally formed in a sleeve 23 fitting within the walls of the spinneret 2 and the reoess Il on the supply head 3. In the space back of the plate 22, there is disposed a distributor member having a transverse plate 24 from which the concentric partitions 25 extend into contact with plate 22. A transverse rib or partition 26 divides the space back of the plate 24 into two compartments or chambers A and B. A locating pin 2'l extends from a bore in one of the walls 28 extending back of the plate 24 through a slot in sleeve 23 to a slot 29 in the supply head 3. This locating pin 21 is arranged so that the passages 8 and I are each associated with only one of the compartments A and B respectively on either side of the rib 28. The passages 30 Join compartment B with alternate regions or chambers between the concentric partitions 25, while passages 3| connect thecompartment A with the other annular regions or chambers (including the central region) between partition 25. Passages f32 connect the corresponding regions and chambers in front of and in back of plate 22. The oriflces of the spinneret are arranged to face alternate. annular regions or chambers between the annular partitions 2|, namely C; and Cs. thus leaving blank the portions of the spinneret face opposite the intervening chambers C, Ca and C4 between partitions 2|..`

The operation of the device of Figures 4 to '1 is analogous to that of Figures 1 to 3, the spinning materials or solutions immediately behind the spinneret face being arranged as concentric strata instead of the' parallel linear strata of Flgures 1 to 3. As in Figures 1 to 3,' the partition may be of Y-shape and an additional spinning material feed pipe similar to 6 and 1 may be provided and connected with the third compartment tims provided by the Y-shape of parnnon ze. In'

such event. the third compartment may be connected with a separate region or chamber between the partitions by passages similar to and 3|, so that the spinning materials will alternate in sequence to provide fllaments similar to those of Figure 9. `Thus the third spinning material may be directed into the chamber Cz, leaving the other two materials to follow the same channels as shown in the drawing.

The following examples are illustrative of the' invention:

Ezample 1 Equal volumetric amounts of two different types of viscose solutions were spun, through a form of apparatus similar to that described above and shown in Flgure 4, into a spinning bath containing 10% sulfuric acid, 2% zinc sulfate and 19% sodium sulfate at a temperature of 45 C. One of the types of viscose solution was made from wood pulp using 30% carbon disulfide based onthe air dry weight of the pulp and contained 71;% cellulose and 61,12% sodium hydroxide. This viscose was aged for 100 hours and had a common salt point of 1.9. The other type of viscose solution was made from cotton pulp using 44% carbon disulfide based on the air dry weight of the pulp and contained 'W2% cellulose and 8% sodium hydroxide. To this viscose was added 6% finely ground titanium dioxide based on the weight of cellulose present. This viscose was aged for 48 hours and had a common salt point of 5.5. The young viscose containing titanium dioxide was allowed to pass through the apparatus, so as to enter the blank spaces of the spinneret face C, Cz and C4. The other viscose entered the alternate spaces facing the spinneret orifices C1 and aaaaoac Ca. Owing to the more rapid setting up or shrinkage rate of the older viscose the titanium dioxide containing viscose almost completely surrounded the other viscose to give a cross section approaching closely that shown in Figure 8a. The resulting filaments which were of 5 denier had a dull delustered appearance owing to the presence of the titanium dioxide on the outside sheath of the filament.

Eaample 2 Two different types of viscose' solution were prepared and spun exactly the same as in Example i, with the exception that the titanium diwood pulp instead ofbeing added to the younger viscose. The cross section which was of the type shown in Flgure 8a contained the titanium dioxide viscose surrounded by the other viscose, which imparted to the filaments a glossy delustered appearance owing to the presence of the delustrant in the core of the filament.

Ezample 3 Two different types of viscose solution were 'prepared and spun exactly as in Example 1, with the exception` that the young titanium dioxide containing viscose was allowed to pass through the apparatus so as to enter the spaces C1 and Cz facing spinneret orifices, and the old viscose to enter theface blank spaces C, C2 and C4. The r'esulting cross section was of the type illustrated in Figure 8c with the titanium dioxide containing viscose only partially surroundingthe other viscose.

In the claims, the term "alternate" is intended to refer to corresponding members of a series of two or greater than two members, which series may be repetitive. For example, the unit of a three-membered series would be ABCB, which could be partially repeated as in: ABCBA or ABCBABCB' It is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined by the appended claims.

We claim:

1.`Fi1aments of regenerated cellulose of com'- posite character whose transverse cross-section comprises three distinct components, one between two others, the intermediate component being substantiaily free of a pigment and the outer components containing a pigment, and the outer portions'bein'g generally symmetrically arranged with respect to the intermediate portion.

2. Filaments of composite character whose transverse cross-section comprises three distinct components. one between two others, the intermediate component being of a composition different from that of the outer components, said outer components containing a visibly contrasting material in finely subdivided form.

3. Filaments of composite character whose transverse cross-section comprises three distinct components, one between two others, the intermediate component being o f a composition different from that of the outer components, and said outer components containing a colored material in flnely subdivided form.

4. Fllaments of composite character whose transverse cross-section comprises three distinct components, one between two others, the intermediatel component being of a composition different from that of the outer components, said outer components containing a delustrant in flnely subdivided form, the intermediate component being substantiaily free of the delustrant.

5. Filaments of regenerated cellulose of com- .posite character whose transverse cross-section 7. Filaments oi' regenerated cellulose of composite character whose transverse cross-section comprises three distinct components. one hetween two others, the outer components containing a visibly contrasting material in finely subdivided i'orm, said filaments being crlmpedby virtue o! diflerent shrinkage characteristics of the regenerated cellulose components.

8. Filaments of regenerated cellulose of composite character whose transverse cross-section comprises three distinct components, one between two others, the intermediate component and each of thetwo outer components being derived from viscoses having different characteristics imparting to the finalcomposite fllament a crimped condition.

WAYNE A. SISSON. WESLEY L. WEBB.

REFEBENCES CITED The following references are of record in the file of this patent:

UNITED sTATEs PA'rEN'rs Name Date Hermann July 30, 1940 Number Number Number Ser. NO. 354,117,

OTHER REFERENCES Thiniiis,l (A. P. C.) pub. Apr.

Images