Trilobal filaments and spinnerets for producing the same

Abstract

Various implementations include a filament that includes three lobes that extend from a central portion of the filament, and the central portion defines an axial void. Each lobe bulges outwardly at its proximal end adjacent the central portion and has edges that form a continuous concave curve toward its distal end relative to an axis A-A that extends through the distal end of the respective lobe and the central portion of the filament. Thus, a width of each lobe at the proximal end thereof is greater than a width of each lobe at or adjacent the distal end, and adjacent edges of adjacent lobes intersect each other at concave proximal ends of the adjacent edges.

Claims

1. A spinneret plate for producing filament, the spinneret plate comprising one or more capillaries, each capillary comprising a substantially hexagonal shaped central area, an outer radial area that is radially spaced apart from the substantially hexagonal shaped central area, and legs that extend between the outer radial area and the substantially hexagonal shaped central area, wherein the capillary defines three openings, each opening being defined between the substantially hexagonal shaped central area, the outer radial area, and two adjacent legs, wherein each opening has a proximal end adjacent the substantially hexagonal shaped central area and a rounded tip at a distal end adjacent the outer radial area, wherein the rounded tip has a proximal end that is a closest portion of the rounded tip to the substantially hexagonal shaped central area, and the proximal end of the opening has a greater width than the distal end such that each opening has a substantially triangular shape, and an outer side of each opening between the proximal end of the rounded tip at the distal end and the proximal end of the opening is substantially straight.

2. The spinneret plate of claim 1, wherein the proximal end of each opening has a geometric center defined by an intersection of two adjacent sides of the substantially hexagonal shaped central area adjacent the opening.

3. The spinneret plate of claim 2, wherein lines extending through the distal end of each opening and a center of the hexagonal shaped central area intersect at 120°.

4. The spinneret plate of claim 1, wherein lines extending through the distal end of each opening and a center of the hexagonal shaped central area intersect at 120°.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Various implementations are explained in even greater detail in the following exemplary drawings. The drawings are merely exemplary to illustrate the structure of various devices and certain features that may be used singularly or in combination with other features. The invention should not be limited to the implementations shown.

(2) FIG. 1 illustrates an end view of a filament in the prior art.

(3) FIG. 2 illustrates an end view of a filament according to one implementation.

(4) FIG. 3 illustrates an end view of a plurality of filaments, such as the filament shown in FIG. 2.

(5) FIG. 4 illustrates a spinneret plate having a plurality of capillaries according to one implementation.

(6) FIG. 5 illustrates an end view of one of the capillaries of the spinneret plate of FIG. 4.

(7) FIG. 6 illustrates a cross sectional view of the capillary in FIG. 5 taken along the G-G line.

DETAILED DESCRIPTION

(8) Various implementations include a thermoplastic polymer filament that provides improved soil hiding without dulling the luster of the filament. In addition, the filament maintains its color over a wide temperature range and is durable. Such a filament may be useful in carpets or textiles, for example. In addition, various implementations include a spinneret plate that defines one or more capillaries for producing the filament.

(9) For example, FIG. 2 illustrates one implementation of a filament 100. The filament 100 includes three lobes 102, 104, 106 that extend from a central portion 108 of the filament 100, and the central portion 108 defines an axial void 110. Each lobe 102, 104, 106 bulges outwardly at its proximal end 112 adjacent the central portion 108 and has edges 116a, 116b that form a continuous concave curve toward its distal end 114 relative to an axis A-A that extends through the distal end 114 of the respective lobe 102, 104, 106 and the central portion 108 of the filament 100. Thus, a width W.sub.p of each lobe 102, 104, 106 at the proximal end 112 thereof is greater than a W.sub.D at or adjacent the distal end 114, and adjacent edges 116a, 116b of adjacent lobes intersect each other at concave proximal ends 117 of the adjacent edges 116a, 116b.

(10) In addition, line B-B is tangential to edge 116b of lobe 106 at the proximal end 117 of the edge 116b, and line C-C is tangential to edge 116a of lobe 102 at the proximal end 117 of the edge 116a. Edge 116b of lobe 106 is adjacent edge 116a of lobe 102, and lines B-B and C-C intersect at an angle Θ.sub.I of 120°. However, in other implementations, Θ.sub.I is between 120° and 180°.

(11) In addition, line D-D is perpendicular to the axis A-A that extends through the distal end 114 of lobe 102 and the central portion 108, and line E-E is tangential to a portion 115 of a tip portion of the lobe 102 adjacent the distal end 114 of lobe 102. Lines D-D and E-E intersect at an angle Θ.sub.T of 30°. However, in other implementations, Θ.sub.T is between 0° and 45°.

(12) Furthermore, in the implementation shown in FIG. 2, the distal end 114 of each lobe is aligned with the intersection 117 of the other two lobes. In particular, line A-A extending through the distal end 114 of lobe 102 and central portion 108 extends through the intersection 117 of the adjacent edges 116a, 116b of adjacent lobes 104 and 106. Similarly, line A-A extending through the distal end 114 of lobe 104 and central portion 108 extends through the intersection 117 of adjacent edges 116a, 116b of adjacent lobes 102 and 106. And, line A-A extending through the distal end 114 of lobe 106 and central portion 108 extends through the intersection 117 of adjacent edges 116a, 116b of adjacent lobes 102 and 104. However, in other implementations, the lobes may not be equispaced about the central portion.

(13) The filament 100 also has a radius R1 that extends from the central axis F of the filament 100 to the distal end 114 of any one of the lobes 102, 104, 106 and a second radius R2 that extends from the central axis F to the intersection of adjacent edges 116a, 116b of any two adjacent lobes 102, 104, 106. A ratio of the radius R1 to the radius R2 defines an external modification ratio (R1/R2) of between 2.0 and 2.5. For example, in one implementation, the external modification ratio is 2.2. In addition, each distal end 114 has a tip radius R3, and a ratio of the radius R1 to the tip radius R3 defines a first tip ratio (R1/R3) of between 0.17 and 0.27 (e.g., 0.21). A ratio of the radius R2 to the tip radius R3 defines a second tip ratio (R2/R3) of between 0.4 and 0.6 (e.g., 0.55).

(14) In other implementations, the tip portion adjacent the distal end 114 of each lobe is non-circular shaped.

(15) The void 110 shown in FIG. 1 has three concave shaped sides 111a, 111b, 111c relative to the central axis F that extends axially through the void 110. The sides 111a-c define an acorn or bulging triangular shape. In addition, vertices 113 of the void 110 are defined by each pair of intersecting sides 111a-111c, and each vertex 113 is aligned with the intersection 117 of the adjacent edges 116a, 116b of adjacent lobes 102, 104, 106 that is nearest the respective vertex 113 and the central axis F. In other implementations, the void 110 is round or triangular.

(16) According to some implementations, an area of the void 110 is 2% to 3.5% of a cross sectional area of the filament 100. And, a modification ratio of the radius R.sub.V from the central axis F to one of the vertices 113 to the radius R.sub.S from the central axis F to a midpoint of one of the sides 111a-c (R.sub.V/R.sub.S) is between 1.0 and 2.0 (e.g., 1.5 to 2.0).

(17) According to some implementations, the void 110 causes light to scatter when passing through the filament 100, which helps with hiding soil. In addition, the low external modification ratio of R1/R2 provides less surface area to which soil can cling and is durable.

(18) The thermoplastic polymer used to produce the filament 100 in FIGS. 2 and 3 includes Nylon 6, but other suitable thermoplastic polymers may be used in other implementations. For example, other exemplary polymers include Nylon 6,6, polyethylene terephthalate (PET), and polytrimethylene terephthalate (PTT). The relative viscosity of the nylon 6 is between 2.4 and 3.6. The filament 100 is at least 24 denier, but other implementations may have various other suitable deniers.

(19) Various implementations also include a spinneret plate for producing filament. FIG. 4 illustrates a spinneret plate 500 that includes a plurality of capillaries 502. FIG. 5 illustrates an end view of one capillary 502. As shown in FIG. 5, the capillary 502 includes a hexagonally shaped central area 504, an outer radial area 506 that is radially spaced apart from the hexagonally shaped central area 504, and legs 508a, 508b, 508c that extend between the outer radial area 506 and the hexagonally shaped central area 504. The capillary 502 defines three openings 510a, 510b, 510c, and each opening 510a, 510b, 510c is defined between the substantially hexagonal shaped central area 504, the outer radial area 506, and two adjacent legs 508a, 508b, 508c. Each opening 510a, 510b, 510c has a proximal end 512 adjacent the substantially hexagonal shaped central area 504 and a distal end 514 adjacent the outer radial area 506. The proximal end 512 has a greater width than the distal end 514 such that each opening 510a, 510b, 510c has a substantially triangular shape.

(20) In addition, the proximal end 512 of each opening 510a, 510b, 510c has a geometric center 516 defined by an intersection of two adjacent sides of the substantially hexagonal shaped central area 504 adjacent the respective opening 510a, 510b, 510c.

(21) The distal end 514 of each opening 510a, 510b, 510c has a rounded tip. For example, the rounded tip of each opening 510a-c may have a diameter D.sub.T of 0.16 mm. However, in other implementations, the tip may have a different diameter or be more pointed.

(22) In the implementation shown in FIG. 5, the width W.sub.L of each leg 508a, 508b, 508c is 0.076 mm, the length L.sub.L of each leg 508a, 508b, 508c is 0.11 mm, the width W.sub.AS between outer ends of adjacent legs 508a, 508b, 508c is 0.67 mm, the distance D.sub.CV between the center 516 of the hexagonal area 504 and one of the vertices 518 of the hexagonal area 504 is 0.31 mm, the distance D.sub.CL between the center 516 and an outer end of one of the legs 508a, 508b, 508c is 0.34 mm, and the distance D.sub.CT between the center 516 and a proximal end 520 of a tip of one of the openings 510a, 510b, 510c is 1.05 mm. In addition, lines H-H extending through the distal end 514 of each opening 510a, 510b, 510c and the center 516 are 120° apart.

(23) FIG. 6 illustrates a cross sectional view of the capillary 502 shown in FIGS. 4 and 5 as viewed through the G-G line shown in FIG. 5. The capillary 502 is 6 mm deep, but in other implementations, this depth may be changed depending on the drawing speed and polymer being used.

(24) The polymer exiting the end of the capillary 502 exits in three separate strands having the shape of the openings 510a, 510b, 510c, and each strand bulges radially outwardly such that the strands merge together, forming the intersection 117 of adjacent lobes 102, 104, 106 and the central portion 108 and void 110 of the filament 100 shown in FIG. 2.

(25) In addition, the filament 100 may be a continuously drawn filament or may be a crimp and cut filament (e.g., to form staple fibers).

(26) The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

(27) While the foregoing description and drawings represent the preferred implementation of the present invention, it will be understood that various additions, modifications, combinations and/or substitutions may be made therein without departing from the spirit and scope of the present invention as defined in the accompanying claims. In particular, it will be clear to those skilled in the art that the present invention may be embodied in other specific forms, structures, arrangements, proportions, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. One skilled in the art will appreciate that the invention may be used with many modifications of structure, arrangement, proportions, materials, and components and otherwise, used in the practice of the invention, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present invention. In addition, features described herein may be used singularly or in combination with other features. The presently disclosed implementations are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims and not limited to the foregoing description.

(28) It will be appreciated by those skilled in the art that changes could be made to the implementations described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular implementations disclosed, but it is intended to cover modifications within the spirit and scope of the present invention, as defined by the following claims.