Highly functional polyethylene fibers, woven or knit fabric, and cut-resistant glove
A polyethylene fiber characterized by having an intrinsic viscosity [η] of 0.8 dL/g or more and less than 5 dL/g; being composed of a repeating unit substantially derived from ethylene; having pores formed inside of the fiber; having an average diameter of the pores of ranging from 3 nm to 1 μm when the diameter is measured, by each pore being approximated by a column, at a contact angle of 140 degrees, in a mercury intrusion method; a porosity of the pores of ranging from 1.5% to 20%; and having a tensile strength greater than or equal to 8 cN/dtex.
1. A polyethylene fiber comprising a polyethylene, wherein
the polyethylene has an intrinsic viscosity [η] of greater than or equal to 0.8 dL/g, and less than 5 dL/g, and substantially contains ethylene as a repeating unit,
the polyethylene fiber comprises pores formed inside of the fiber,
the average diameter of the pores is in the range of from 3 nm to 200 nm when the diameter is measured, by each pore being approximated by a column, at a contact angle of 140 degrees, in a mercury intrusion method,
the porosity of the fiber is in the range of from 1.5% to 15%, and
the polyethylene fiber has a tensile strength greater than or equal to 8 cN/dtex.
2. The polyethylene fiber according to claim 1 , wherein the thermal conductivity in a fiber axis direction at a temperature of 300 K is in the range of from 6 W/mK to 50 W/mK.
3. The polyethylene fiber according to claim 1 , wherein the polyethylene fiber contains an organic substance having a high affinity for a disperse dye and a polyethylene.
4. The polyethylene fiber according to claim 1 , wherein the weight average molecular weight (Mw) of the polyethylene is in the range of from 50,000 to 600,000, and the ratio (Mw/Mn) of the weight average molecular weight to the number average molecular weight (Mn) is less than or equal to 5.0.
5. The polyethylene fiber according to claim 1 , wherein the specific gravity of the polyethylene fiber is greater than or equal to 0.90, and the modulus of the polyethylene fiber is in the range of from 200 cN/dtex to 750 cN/dtex.
6. A dyed polyethylene fiber comprising the polyethylene fiber as defined in claim 3 , wherein the polyethylene fiber is dyed with a disperse dye.
7. The dyed polyethylene fiber according to claim 6 , wherein the evaluation value of a fastness to washing in compliance with JIS L-0844 A-1 or the evaluation value of a fastness to dry cleaning in compliance with JIS L-0860 A-1 of the dyed polyethylene fiber is higher than or equal to grade 3.
8. A covered elastic yarn comprising an elastic fiber being covered by the polyethylene fiber as defined in claim 3 .
9. The polyethylene fiber according to claim 2 , wherein the polyethylene fiber contains an organic substance having a high affinity for a disperse dye and a polyethylene.
10. The polyethylene fiber according to claim 2 , wherein the weight average molecular weight (Mw) of the polyethylene is in the range of from 50,000 to 600,000, and the ratio (Mw/Mn) of the weight average molecular weight to the number average molecular weight (Mn) is less than or equal to 5.0.
11. The polyethylene fiber according to claim 2 , wherein the specific gravity of the polyethylene fiber is greater than or equal to 0.90, and the modulus of the polyethylene fiber is in the range of from 200 cN/dtex to 750 cN/dtex.
12. The polyethylene fiber according to claim 1 , wherein the polyethylene fiber comprises pores inside the fiber that communicate with the surface of the fiber.
13. The polyethylene fiber according to claim 1 , wherein the polyethylene fiber is manufactured by a manufacturing method including a drawing process step, the drawing process step comprising drawing a non-drawn filament comprising the polyethylene at a deformation rate of greater than or equal to 0.05 m/sec.
14. The polyethylene fiber according to claim 3 , wherein the exhaustion rate of the polyethylene fiber is greater than or equal to 17%, and the exhaustion rate is obtained when dyeing is performed at 100° C. at a bath ratio of 1:100 for 90 minutes by using a dye liquor that is prepared to have such a concentration as to contain 0.4 g/L of the disperse dye.
15. The polyethylene fiber according to claim 3 , wherein the organic substance having the high affinity for the disperse dye and the polyethylene contains at least one polyether compound having a molecular weight greater than or equal to 500.
16. The polyethylene fiber according to claim 3 , wherein the proportion of the organic substance to the polyethylene fiber is in the range of from 0.005 mass % to 10.0 mass %.
17. A protective woven/knitted textile comprising, as at least a portion of the protective woven/knitted textile, the polyethylene fiber as defined in claim 3 , wherein the protective woven/knitted textile has an index value of a coup tester of greater than or equal to 3.9.
18. A cut-resistant glove comprising the protective woven/knitted textile as defined in claim 17 .