US3843098A - Fluid layering assembly for attachment to a jet or spinneret for production of side-by-side and sheath-core fibers - Google Patents

Abstract

A fluid layering assembly for attachment to an existing jet or spinneret for spinning from fiber forming solutions or melts side-by-side and sheath-core bicomponent fibers and formed of three concentric cylindrical pipes. Each pipe has an inlet and an outlet for receiving into and dispensing from the pipe the fiber forming solution or melt. The inner pipe has attached thereto a breaker plate, which has formed therein a central opening for receipt of flow from outlet of the inner pipe and a plurality of openings arranged radially around the central opening for receipt from the plurality of openings the flow from the outlet of the middle pipe. A chamber in axial alignment with the three pipes and located downstream of the breaker plate receives the flow from the outlet of the outer pipe as well as the flows from the breaker plate and combines all of the flows for extrusion through the jet or spinneret orifices. The breaker plate breaks up the flow between the inner and middle pipes and produces individual circular streams of material surrounded by material flowing in the inner and outer pipes. The breaker plate may also be rotatably adjustable relative to the jet or spinneret orifices for determining whether fibers having side-by-side or sheath-core fiber cross-sections are obtained.

Description

United States Patent [191 Phillips et al.

1 51 Oct. 22, 1974 FLUID LAYERING ASSEMBLY FOR ATTACHMENT TO A JET OR SPINNERET FOR PRODUCTION OF SIDE-BY-SIDE AND SHEATH-CORE FIBERS [75] Inventors: Bobby M. Phillips; Hal 0. Jones,

both of Kingsport, Tenn.

[73] Assignee: Eastman Kodak Company,

Rochester, NY.

22 Filed: Aug. 6, 1973 211, Appl. 190.; 385,760

Primary ExaminerRobert W. Jenkins Attorney, Agent, or Firm-Malcolm G. Dunn; Daniel B. Reece, Ill

[57] ABSTRACT A fluid layering assembly for attachment to anexisting jet or spinneret for spinning from fiber forming solutions or melts side-by-side and sheath-core bicomponent fibers and formed of three concentric cylindrical pipes. Each pipe has an inlet and an outlet for receiving into and dispensing from the pipe the fiber forming solution or melt. The inner pipe has attached thereto a breaker plate, which has formed therein a central opening for receipt of flow from outlet of the inner pipe and a plurality of openings arranged radially around the central opening for receipt from the plurality of openings the flow from the outlet of the middle pipe. A chamber in axial alignment with the three pipes and located downstream of the breaker plate receives the flow from the outlet of the outer pipe as well as the flows from the breaker plate and combines all of the flows for extrusion through the jet or spinneret orifices. The breaker plate breaks up the flow between the inner and middle pipes and produces individual circular streams of material surrounded by material flowing in the inner and outer pipes. The breaker plate may also be rotatably adjustable relative to the jet or spinneret orifices for determining whether fibers having side-by-side or sheath-core fiber crosssections are obtained.

2 Claims, 11 Drawing Figures PATENTEDHETZZIQH 3.843098 sum 20: 2

FLUID LAYERING ASSEMBLY FOR ATTACHMENT TO A JET OR SPINNERET FOR PRODUCTION OF SIDE-BY-SIDE'AND SHEATH-CORE FIBERS BACKGROUND OF THE INVENTION This invention is directed to a fluid layering assembly to be connected to an existing type jet or spinneret for spinning from flows of fiber forming solutions or melts side-by-side and sheath-core bicomponent fibers.

It has long been known that it is difficult to mix inherently different viscous fluids in fiber forming solutions and melts so as to provide an entirely homogeneous material when extruded from a jet or spinneret. Although it is possible to break up streams into smaller streams, there is essentially no mixing or diffusing into each other for short contact times. This phenomenon was noted, for instance, in the Braunlich patent, US. Pat. No. 2,815,532, granted Dec. 10, 1957. Braunlichs patented invention took advantage of this phenomenon by controlling mechanically the composition of the final filaments by means of alignment between perforated proportioning members as well as between one or more such proportioning members and the orifices in the jet or spinneret. In this manner Braunlich found it possible to vary the different materials in such a way as to form a sharp dividing line between two materials when the fiber was seen in cross-section. Braunlich could control the dividing line or interface of the filament so that substantially half of the filament was of one material or color and the other half was of another color or material. Braunlich found that by varying the proportion of materials, the dividing line could be relocated to give any relative proportion in any desired length of the filament, or to provide a relatively diffused dividing line on either side of which there was a preponderance of one material over the other. Also, the location of the various orifices could be controlled so that sheathed filaments having a core of different color and/or material than the outer coating could be obtained. Further, the sheath or outer coating could be controlled to provide annular or irregular shapes. Braunlich obtained this control mechanically by an arrangement of proportioning or mixing disc-like members which could be used singly or in groups to provide for the introduction of a plurality of different fluids as well as to increase the tendency of the blending or mixing of only one liquid stream. The disc-like members each had a plurality of orifices extending through the member and a group of orifices which extended only partially through the member and communicated with a bore or hollowed interior to which a second fluid was introduced. The relative location and number of the orifices communicating with the interior of the hollowdisc or member with respect to the orifices providing communication through the member controlled the pattern and characteristics of the extruded filament,

A fiber forming solution may be cellulose acetate in acetone or viscose and the like, and the fiber forming melt may be polyester, nylon and the like.

Side-by-side and sheath core spun filaments are of interest because of their self-crimping or novel bonding or dyeing effects which can bepbtained when the component substances of the fiber forming solution or melt differ in an appropriate physical and/or chemical. respect. There is a large body of patent art available that -is concerned with these types of spinning. The selfcrimping, for instance, is effected by the fact that one of the component substances of the fiber shrinks under conditions of appropriate heat, for instance, more than the other component substance, thereby resulting in curling or crimping and pulling the fiber into a helical configuration.

In a side-by-side filament, two or more filamentary compositions or component substances form along the length of thefilament in a side-by-side relationship. In a sheath core filament, two or more filamentary compositions or component substances form along the length of the filament so that there is a sheath of one material that is formed around a core of another material so that the core is embedded in the sheath.

In the instance of a sheath-core filament, a high strength polymer may be used for the core and a polymer of desirable surface characteristics might be used for the sheath to produce a filament having high strength properties combined with a good appearance. Also, an inexpensive core fiber of relatively inferior properties might be encased in a sheath of highcost polymer that has the desiredcharacteristics, in order to achieve a fiber or filament having a substantially lower cost than if it were to be made entirely of the expensive polymer. Further, a polymer having as an extruded fiber favorable hand and dye characteristics may be used as a sheath on a core of relatively inexpensive polymer having as an extruded fiber good mechanical prbperties.

In another instance of the side-by-side filament, a composite filament of substantially uniform crosssection composed of segments of at least two dissimilar man-made polymeric compositions with the crosssection having at least two segments of at least one of the polymers may be extruded, and subsequently separated into its component sections by mechanical action to produce filaments having one or more sharp longitudinal edges. The purpose of this construction is to produce fabrics that are silk-like.

The possibilities and advantages for both types of fiber constructions, side-by-side and sheath core bicomponent fibers, are endless.

The object of the present invention, therefore, is to provide as attachment to an existing type jet or spinneret a fluid layering assembly that is simply constructed and may be used in cooperation with the jet or spinneret to spin from flows of fiber forming solutions or melts side-by-side and sheath-core bicomponent fibers. The terms jet and spinneret, for purposes of this disclosure are used interchangeably.

SUMMARY OF THE INVENTION The invention is a fluid layering assembly to be attached to a jet or spinneret for spinning from fiber forming solutions or melts side-by-side and sheath-core bicomponent fibers, the assembly being simply formed of three concentric cylindrical pipes with each pipe having an inlet and an outlet for receiving into and dispensing from the pipe a fiber forming solution or melt. The inner concentric pipe has attached thereto a breaker plate having formed therein a central opening for the receipt of the flow from the outlet of the inner pipe and a plurality of openings arranged radially around the central opening for receipt from the plurality of openings the flow from the outlet of the middle concentric pipe. A chamber in axial alignment with the three concentric pipes and located downstream of the circular streams of material which are surrounded by material flowing in the inner and outer concentric pipes. The breaker plate may also be rotatably adjustable relative to the orifices of the jet or spinneret, thereby determining whether fibers having side-by-side or sheath-core fiber cross-sections are obtained.

BRIEF DESCRIPTION OF THE INVENTION In the drawings:

FIG. 1 is an elevational view in cross-section of the fluid layering assembly and the attached jet or spinneret;

1 FIG. 2 illustrates the fiber forming flows in the concentric pipes upstream of the breaker plate;

FIG. 3 illustrates the fiber forming flows in the chamber downstream of the breaker plate;

. FIG. 4 illustrates the relative orientation of the plurality of holes (shown in phantom) in the breaker plate to the orifices in the jet or spinneret downstream of the breaker plate;

FIG. 5 is an enlarged view of one of the pie-shaped sections shown in FIG. 4 showing the flow that feeds each jet or spinneret orifice;

. FIG. 6 illustrates the fiber cross-section of a sheathcore bicomponent fiber obtained from the pie-shaped section of flow shown in FIG. 5 from cellulose acetate dopes;

FIG. 7 is a view similar to FIG..4 with the breaker plate being rotated clockwise degrees to change the relative orientation of the plurality of holes (shown in phantom) in the breaker plate to the orifices in the jet or spinneret downstream of the breaker plate;

FIG. 8 is an enlarged view of one of the pie-shaped sections shown in FIG. 7 showing the flow that feeds each jet or spinneret orifice;

FIG. 9 illustrates the fiber cross-section of a sheathcore bicomponent fiber obtained from the pie-shaped section of flow shown in FIG. 8 from cellulose acetate dopes;

FIG. 10 is a view illustrating the pie-shaped section of flow feeding each jet or spinneret orifice from a still different orientation of the plurality holes in the breaker plate to orifices in the jet or spinneret; and

FIG. 11 illustrates the fiber cross-section of a side-byside bicomponent fiber obtained from the pie-shaped section of flow shown in FIG. 10 from cellulose acetate dopes. DESCRIPTION OF THE PREFERRED EM- BODIMENT In reference to FIG. 1 the fluid layering assembly is shown in general at 10 and the jet or spinneret to which the assembly may be attached is shown at 12. The jet or spinneret may be either one for handling a fiber forming solution or a fiber forming melt, and the fluid layering assembly may be appropriately heated depending upon the nature of the fiber forming flows to be handled.

The fluid layering assembly 10 comprises three concentric cylindrical pipes with each pipe having a separate inlet and outlet for receiving and dispensing a fluid or flow of fiber forming solution or melt. The inner pipe 14 has an inlet 16 and an outlet 18; the'middle pipe 20 has an inlet 22 and an outlet 24; and the outer pipe 26 has an inlet 28 and an outlet 30. A breaker plate 32 may be suitably, threadably attached at the outlet 18 of the inner pipe '14.

The breaker plate has a central opening 34 that communicates directly with the outlet 18 of the inner pipe 14, and a plurality of openings 36 arranged radially around the central opening 34 and which communicate directly with the outlet 24 of the middle pipe 20. The breaker plate, as previously indicated, breaks up the flow between the inner and middle concentric pipes and produces through the plurality of openings 36 individual circular streams of material which are surrounded by material flowing in the inner and outer concentric pipes.

A chamber 38 is provided downstream of and in axial alignment with the three concentric cylindrical pipes and the breaker plate for receiving and combining the flows from the outer pipe as well as the inner and middle pipes and the breaker plate. The chamber is provided with an outlet 40 for the combined flows from the chamber to the orifices of the jet or spinneret which may be attached to the outlet 40. As may be observed from FIG. 1 the fluid layering assembly is relatively simple in construction and appearance, and will require relatively low maintenance expense.

The breaker plate may be fixed in position so that its plurality of openings 36 will bear a predetermined oriented relation to the orifices of the jet or spinneret 12. The breaker plate may, and preferably, be rotatably adjustable and thereby enable the fluid layering assembly in cooperation with the jet or spinneret to produce fibers having either side-by-side or sheath-core crosssections, or a combination of both fiber cross-sections at the same time. A single fluid layering assembly having a rotatably adjustable breaker plate would be more versatile, although it would also be possible, within the scope of the defined invention, to form separate assemblies each with a different orientation of holes in a fixed breaker plate to the jet or spinneret orifices.

The inner concentric pipe 14 may be suitably secured to the middle pipe 20 at one end as by welding at the intersection where the inner pipe passes outwardly through the one end of the middle pipe. The outer pipe 26 may be suitably attached to the middle pipe 20 by the threaded arrangement shown generally at 42. The chamber 38 may be formed by the threaded arrangement shown in general at 44 and through which arrangement the downstream ends of the pipes are threadedly interconnected, as illustrated. In this manner, the pipes may be readily disassembled for repair and/0r cleaning, if desired.

OPERATION In operation, a separate fluid or fiber forming flow may be introduced into each of the inlets of the three concentric pipes. The same material, preferably, may be introduced into the inner and outer concentric pipes.

For purposes of illustration, a red cellulose acetate dope, identified as I in the drawings, was introduced in inlet 16 of the inner pipe and in inlet 28 of the outer pipe 26; and a blue cellulose acetate dope, identified as H in the drawings, was introduced in the inlet 22 of the middle concentric pipe 20. The breaker plate 32 was positioned so that the plurality of openings 36 were oriented at the same angular relation (note the center lines in FIG. 4) with the orifices 46 of the jet or spinneret 12. In this example the breaker plate is shown as having eight openings and the jet as also having eight orifices.

The flow of the materials is essentially laminar, meaning that there will be no significant mixing or diffusion for short contact times of the neighboring layers. Thus the interfaces will be substantially preserved throughout. FIG. 2 shows the appearance of the flows upstream of the breaker plate, and FIG. 3 shows the appearance of the flows downstream of the breaker plate after the fiber forming solutions, in this instance cellulose acetate dopes, have become combined in the chamber 38.

FIG. 4, as previously mentioned, shows the angular relation of the plurality of breaker plate openings 36 to the jet orifices 46. The pipe-shaped sections 48 in FIG. 4 and the section in FIG. 5 represent the flow of materials feeding each jet orifice. The cellulose acetate red dope (I) formed a sheath of material around the core of cellulose acetate blue dope (II) so that the resulting fiber cross-section had an appearance somewhat similar to that illustrated in FIG. 6. When spinning cellulose acetate dopes, the resulting fiber cross-section tends to shrink inwardly in an irregular manner because of solvent loss. A melt flow, such as polyester polymer, would tend to result in a more rounded fiber crosssection when the polymer is extruded through circular orifices. The flow from the outer pipe is essential to assure that in spinning fibers having sheath-core cross- 1 sections the core remains completely inside the pieshaped section shown in FIGS. 5, 6, 8 and 9. When the core stream is bisected by the dividing streamline between two pie-shaped sections, the sandwich fiber cros-. ssection of FIGS. 10 and 11 will occur because the core streams feed material to each of the adjacent pieshaped sections.

FIG. 7 shows the change of hole-to-orifice relation when the breaker plate was rotatably adjusted clockwise 10 degrees with respect to the jet or spinneret orifices. FIG. 8 shows how the core of the blue dope (II) material in the pie-shaped section 48' shifted relative to the red dope (I) sheath material, the resulting fiber crosssection appearing as shown in FIG. 9.

The breaker plate was rotatably adjusted still further so that the pie-shaped section 48" showing the flow of material to an individual jet orifice had the appearance of that shown in FIG. 10 with the resulting fiber crosssection being a side-by-side filamentary construction as that shown in FIG. 11.

The number of openings 36 in the breaker plate 32 may vary, as desired, and also there may be a variance in the ratio of openings 36 to the orifices 46 in the jet or spinneret. Other types of holes or openings may be used in the breaker plate, such as triangular, rectangular, square, hexagonal, etc. Various ranges of flow rates may be employed by gear pumps, extruders or the like operating at different pressures and flows with respect to the materials being introduced into the concentric pipes. Also, as previously mentioned, the material flowing into each pipe may be different from those flowing into each of the other pipes.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it. will be understood that variations and modifications can be effected within the spirit and scope of the invention.

We claim:

l. Fluid layering assembly for attachment to a jet or spinneret for spinning from flows of fiber forming solution or melts side-by-side and sheath-core bicomponent fibers, said assembly comprising:

three concentric cylindrical pipes;

a breaker plate means;

each pipe having inlet and outlet means for receiving into and dispensing from the pipe a flow of fiber forming solution or melt;

the inner concentric pipe having attached at its outlet means the breaker plate means; the breaker plate means having formed therein a central opening and a plurality of openings arranged radially around the central opening, the central opening being in communication with the outlet means of the inner concentric pipe and the plurality of openings being in communication with the outlet means of the middle concentric pipe; and means defining a chamber that is downstream of and in axial alignment with the three concentric cylindrical pipes and the breaker plate means for receiving and combining the flows from the outer as well as the inner and middle pipes and the breaker plate means, and an outlet means for the combined flows from the chamber to the orifices of the jet or spinneret which may be attached to the outlet means.

2. A fluid layering assembly as defined in claim 1, and wherein said breaker plate means is rotatably adjustable for positioning the plurality of openings in a predetermined manner relative to the orifices of the jet or spinneret.

Claims (2)

1. Fluid layering assembly for attachment to a jet or spinneret for spinning from flows of fiber forming solution or melts sideby-side and sheath-core bicomponent fibers, said assembly comprising: three concentric cylindrical pipes; a breaker plate means; each pipe having inlet and outlet means for receiving into and dispensing from the pipe a flow of fiber forming solution or melt; the inner concentric pipe having attached at its outlet means the breaker plate means; the breaker plate means having formed therein a central opening and a plurality of openings arranged radially around the central opening, the central opening being in communication with the outlet means of the inner concentric pipe and the plurality of openings being in communication with the outlet means of the middle concentric pipe; and means defining a chamber that is downstream of and in axial alignment with the three concentric cylindrical pipes and the breaker plate means for receiving and combining the flows from the outer as well as the inner and middle pipes and the breaker plate means, and an outlet means for the combined flows from the chamber to the orifices of the jet or spinneret which may be attached to the outlet means.

2. A fluid layering assembly as defined in claim 1, and wherein said breaker plate means is rotatably adjustable for positioning the plurality of openings in a predetermined manner relative to the orifices of the jet or spinneret.

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