MODIFIED CROSS-SECTION LYOCELL MATERIAL FOR TOBACCO FILTER, AND PREPARATION METHOD THEREFOR

• US 20170156394A1
• Filed: 06/30/2015
• Published: 06/08/2017
• Est. Priority Date: 06/30/2014
• Status: Active Grant

• Current Assignee: Kolon Industries Incorporated, KT&G Corporation
• Original Assignee: Kolon Industries Incorporated, KT&G Corporation
• Inventors: KIM, Jong Yeol, KIM, Soo Ho, CHEONG, Bong Su, CHO, Hyun Suk, KI, Sung Jong, JEONG, Jong Cheol, JIN, Sang Woo, LEE, Sang Yoel, KIM, Woo Chul, LEE, Sang Mok
• Granted Patent: US 11,103,003 B2
• Time in Patent Office: Days
• CPC Class Codes: A24D 3/064 having non-circular cross-section
• CPC Class Codes: A24D 3/068 Biodegradable or disintegrable
• CPC Class Codes: A24D 3/10 of cellulose or cellulose derivatives
• CPC Class Codes: B29C 48/0019 combined with shaping by flattening, folding or bending
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/21 the layers being joined at their surfaces
• CPC Class Codes: B29C 48/345 Extrusion nozzles comprising two or more adjacently arranged ports, for simultaneously extruding multiple strands, e.g. for pelletising
• CPC Class Codes: B29K 2001/08 Cellulose derivatives
• CPC Class Codes: B29L 2031/14 Filters optical filters B29L2011/0066, sieves or screens B29L2031/737
• CPC Class Codes: B29L 2031/7416 for cigars or cigarettes
• CPC Class Codes: D01D 4/02 Spinnerettes alloys therefor C22C
• CPC Class Codes: D01D 5/088 Cooling filaments, threads or the like, leaving the spinnerettes
• CPC Class Codes: D01D 5/253 with a non-circular cross section; Spinnerette packs therefor D01D5/38 takes precedence
• CPC Class Codes: D01D 5/28 while mixing different spinning solutions or melts during the spinning operation; Spinnerette packs therefor
• CPC Class Codes: D01F 2/00 Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
• CPC Class Codes: D01F 2/08 Composition of the spinning solution or the bath
• CPC Class Codes: D10B 2503/00 Domestic or personal

Abstract

This invention relates to a lyocell material for a tobacco filter and a method of manufacturing the same, and more particularly to a lyocell fiber having a modified cross-section for a tobacco filter, wherein the cross-sectional shape of a monofilament contained in a lyocell fiber is controlled to increase the external surface area of the fiber, after which then crimps are formed, thereby exhibiting properties equal or superior to those of conventional lyocell materials, even when used in a small amount.

Claims

1. A method of manufacturing a lyocell material having a modified cross-section for a tobacco filter, comprising:

(S1) spinning a lyocell spinning dope comprising a cellulose pulp and an N-methylmorpholine-N-oxide (NMMO) aqueous solution using a spinneret having a plurality of unit holes each having multiple holes;

(S2) coagulating the lyocell spinning dope spun in (S1), thus obtaining a lyocell multifilament;

(S3) water-washing the lyocell multifilament obtained in (S2);

(S4) oiling the lyocell multifilament water-washed in (S3); and

(S5) crimping the lyocell multifilament oiled in (S4), thus obtaining a crimped tow,

wherein the lyocell multifilament comprises a monofilament having a modified cross-section,

the modified cross-section includes a plurality of projections, and

the plurality of projections comes into contact with a first virtual circle and a second virtual circle included in the first virtual circle, is integrally formed with the second virtual circle serving as a center, and comes into contact with the first virtual circle at ends thereof, a ratio (L1/L2) of a radius (L1) of the first virtual circle to a radius (L2) of the second virtual circle ranging from 1.5 to 5.0.

2. The method of claim 1, wherein in (S1), the lyocell spinning dope comprises 6 to 16 wt % of the cellulose pulp and 84 to 94 wt % of the N-methylmorpholine-N-oxide aqueous solution based on a total weight of the spinning dope.

3. The method of claim 2, wherein the cellulose pulp comprises 85 to 97 wt % of alpha-cellulose based on a total weight of the pulp and has a degree of polymerization (DPw) of 600 to 1700.

4. The method of claim 1, wherein the coagulating in (S2) comprises primary coagulation using air quenching (Q/A) including supplying cold air to the spinning dope and secondary coagulation including immersing the primarily coagulated spinning dope in a coagulation solution.

5. The method of claim 4, wherein the air quenching is performed by supplying the cold air at a temperature of 4 to 15°

C. and a wind velocity of 5 to 50 m/s to the spinning dope.

6. The method of claim 4, wherein the coagulation solution has a temperature of 30°

C. or less.

7. The method of claim 1, wherein (S5) comprises crimping the oiled lyocell multifilament using a stuffer box to yield a crimped tow having 15 to 60 crimps per inch.

8. The method of claim 1, wherein (S5) is performed by supplying steam and applying pressure to the lyocell multifilament so that the lyocell multifilament is crimped.

9. The method of claim 8, wherein (S5) is performed by supplying the steam so that a pressure of the steam is 0.05 to 2.0 kgf/cm², and the lyocell multifilament is pressed and crimped using a press roller at a pressure of 1.0 to 4.0 kgf/cm².

10. The method of claim 1, wherein the spinneret is a spinneret having a plurality of unit holes each having three holes, and the lyocell multifilament is configured such that a number of points of contact of the first virtual circle and the second virtual circle with a cross-section of the monofilament is 3.

11. A lyocell material having a modified cross-section for a tobacco filter, manufactured by spinning a lyocell spinning dope comprising a cellulose pulp and an N-methylmorpholine-N-oxide (NMMO) aqueous solution to produce a lyocell multifilament and crimping the lyocell multifilament,

wherein the lyocell multifilament comprises a monofilament having a modified cross-section,

the modified cross-section includes a plurality of projections, and

the plurality of projections comes into contact with a first virtual circle and a second virtual circle included in the first virtual circle, is integrally formed with the second virtual circle serving as a center, and comes into contact with the first virtual circle at ends thereof, a ratio (L1/L2) of a radius (L1) of the first virtual circle to a radius (L2) of the second virtual circle ranging from 1.5 to 5.0.

12. The lyocell material of claim 11, wherein the lyocell spinning dope comprises 6 to 16 wt % of the cellulose pulp and 84 to 94 wt % of the N-methylmorpholine-N-oxide aqueous solution based on a total weight of the spinning dope.

13. The lyocell material of claim 12, wherein the cellulose pulp comprises 85 to 97 wt % of alpha-cellulose based on a total weight of the pulp and has a degree of polymerization (DPw) of 600 to 1700.

14. The lyocell material of claim 11, wherein the lyocell material has a space occupancy of 150 to 400%, as defined as Equation 1 below:

Space occupancy (%)=(area of first virtual circle/cross-sectional area of monofilament contained in lyocell fiber)×

100. 

 

(Equation

     1)

15. The lyocell material of claim 11, wherein the first virtual circle has a radius (L1) of 8 to 30 μ

m.

16. The lyocell material of claim 11, wherein the second virtual circle has a radius (L2) of 3 to 12 μ

m.

17. The lyocell material of claim 11, wherein a number of points of contact of the first virtual circle and the second virtual circle with a cross-section of the monofilament is 3.

18. The lyocell material of claim 11, wherein the first virtual circle and the second virtual circle are concentric.