NATURAL FIBER FELT AND PRODUCTION METHOD THEREOF

Abstract

A natural fiber felt is provided, which is a film formed by processes of binding a natural fiber net with a binder, extruding, drying and shaping the natural fiber net. A surface of the film is coated with a waterproof layer. The foam binder is formed by combining modified starch serving as a binder and urea serving as a foaming agent with water. A water-repellent agent fruit wax emulsion is employed to form the waterproof layer. The natural fiber net is carded by a carding machine at one time, and the foam binder is sprayed onto the natural fiber net to bind the natural fiber net so as to form the film. The product has characteristics of ultra-thinness and high strength with good performances on heat preservation, moisturizing ability, waterproof and air permeability.

Claims

1. A natural fiber felt, which is a film formed by processes of binding a natural fiber net with a binder, extruding, drying and shaping the natural fiber net, wherein a surface of the film is coated with a waterproof layer; wherein the natural fiber net is a fiber net formed by carding natural fibers at one time using a carding machine, and the natural fibers are one of linen fibers, ramie fibers, cotton fibers or combinations thereof; wherein the binder is a foam binder which is a mixture comprises a binder, a foaming agent and water; every 100 parts by weight of foam binders contain 8 to 10 parts by weight of binders, 1 to 3 parts by weight of foaming agents and the balance being water; and the binder is modified starch, and the foaming agent is urea; and wherein the waterproof layer is formed by spraying water-repellent fruit wax emulsion onto the surface of the film; and the fruit wax emulsion is a CFW-type fruit wax emulsion.

2. The natural fiber felt according to claim 1, wherein the modified starch is oxidized cross-linked starch; and the CFW-type fruit wax emulsion comprises 10 wt % to 20 wt % of natural palm wax, 2.5 wt % to 3.0 wt % of morpholine fatty acid salt and the balance being water.

3. The natural fiber felt according to claim 1, wherein the natural fibers are a combination of 90 wt % of linen fibers and 10 wt % of cotton fibers; and the fineness of the linen fibers ranges from 1.5 to 2.5 dtex, the length of the linen fibers ranges from 17 to 25 mm, the fineness of the cotton fibers ranges from 1.5 to 3 dtex, and the length of the cotton fibers ranges from 15 to 35 mm.

4. The natural fiber felt according to claim 1, wherein the natural fibers are a combination of 20 wt % of cotton fibers and 80 wt % of ramie fibers; and the fineness of the cotton fibers ranges from 1.5 to 2.5 dtex, the length of the cotton fibers ranges from 16 to 35 mm, the fineness of the ramie fibers ranges from 3 to 6 dtex, and the length of the ramie fibers ranges from 25 to 45 mm.

5. The natural fiber felt according to claim wherein the natural fibers are 100 wt % of flax short fibers; and the fineness of the flax short fibers ranges from 0.15 to 0.25 dtex, and the length of the flax short fibers ranges from 17 to 25 mm.

6. The natural fiber felt according to claim 1, wherein technical characteristics of the natural fiber felt are as follows: a weight per unit area ranges from 30 to 50 g/m, a thickness ranges from 0.20 to 0.35 mm, a tensile strength ranges from 1400 to 1800 N/m, a tear resistance ranges from 50 to 90 N, a burst strength ranges from 100 to 200 N, and a vertical permeation coefficient ranges from 6.0×10−4 to 8.0×10−4 cm/s.

7. The natural fiber felt according to claim 2, wherein technical characteristics of the natural fiber felt are as follows: a weight per unit area ranges from 30 to 50 g/m, a thickness ranges from 0.20 to 0.35 mm, a tensile strength ranges from 1400 to 1800 N/m, a tear resistance ranges from 50 to 90 N, a burst strength ranges from 100 to 200 N and a vertical permeation coefficient ranges from 6.0×10−4 to 8.0×10−4 cm/s.

8. The natural fiber felt according to claim 3, wherein technical characteristics of the natural fiber felt are as follow weight per unit area ranges from 30 to 50 g/m, a thickness ranges from 0.20 to 0.35 mm, a tensile strength ranges from 1400 to 1800 N/m, a tear resistance ranges from 50 to 90 N, a burst strength ranges from 100 to 200 N, and a vertical permeation coefficient ranges from 6.0×10−4 to 8.0×10−4 cm/s.

9. The natural fiber felt according to claim 4, wherein technical characteristics of the natural fiber felt are as follows: a weight per unit area ranges from 30 to 50 g/m, a thickness ranges from 0.20 to 0.35 mm, a tensile strength ranges from 1400 to 1800 N/m, a tear resistance ranges from 50 to 90 N, a burst strength ranges from 100 to 200 N, and a vertical permeation coefficient ranges from 6.0×10−4 to 8.0×10−4 cm/s.

10. The natural fiber felt according to claim 5, wherein technical characteristics of the natural fiber felt are as follows: a weight per unit area ranges from 30 to 50 g/m a thickness ranges from 0.20 to 035 mm, a tensile strength ranges from 1400 to 1800 N/m, a tear resistance ranges from 50 to 90 N, a burst strength ranges from 100 to 200 N, and a vertical permeation coefficient ranges from 6.0×10−4 to 8.0×10−4 cm/s.

11. A method for producing the natural fiber felt according to claim 1, comprising the following steps: a. treatment of raw material fibers: unpacking the raw material natural fibers, mixing and loosening the natural fibers, and then removing dust and impurities; wherein the natural fibers are one of linen fibers, ramie fibers, cotton fibers or combinations thereof; b. forming a net: carding the natural fibers obtained in step a at one time using a carding machine to obtain a formed natural fiber net; c. binding the net to form a film: spraying a foam binder onto two opposite surfaces of the natural fiber net obtained in step b, and after the spraying, extruding the natural fiber net to form the film; wherein the foam binder is a mixture formed by stirring a binder, a foaming agent and water for 25 to 30 minutes, and every 100 parts by weight of foam binders contain 8 to 10 parts by weight of binders, 1 to 3 parts by weight of the foaming agents and the balance being water; and the binder is modified starch, and the foaming agent is urea; d. drying and shaping: drying the film obtained in step c at a temperature ranging from 145° C. to 160° C. for 0.5 to 1 minutes, and then shaping at a temperature ranging from 150° C. to 165° C. for 0.5 to 1 minutes; e. waterproof treatment spraying water-repellent fruit wax emulsion onto the two opposite surfaces of the film obtained in step d; and f. calendering finish, coiling and warehousing: performing calendering finish to the film obtained in step a using a cold calender, then cutting to form coils, and warehousing the coils to obtain the natural fiber felt.

12. The method for producing the natural fiber felt according to claim 11, wherein technical characteristics of the natural fiber felt produced are as follows: a weight per unit area ranges from 30 to 50 g/m2, a thickness ranges from 0.20 to 0.35 mm, a tensile strength ranges from 1400 to 1800 N/m, a tear resistance ranges from 50 to 90 N, a burst strength ranges from 100 to 200 N, and a vertical permeation coefficient ranges from 6.0×10−4 to 8.0×10−4 cm/s.

13. The method for producing the natural fiber felt according to claim 11, wherein the modified starch in step c is oxidized cross-linked starch; and the fruit wax emulsion in step e is the CFW-type fruit wax emulsion which comprises 10 wt % to 20 wt % of natural palm wax, 2.5 wt % to 3.0 wt % of morpholine fatty acid salt and the balance being water.

14. The method for producing the natural fiber felt according to claim 11, wherein in step d the film is dried at a temperature ranging from 148° C. to 152° C. for 0.7 to 0.9 minutes, and then shaped at a temperature ranging from 158° C. to 162° C. for 0.6 to 0.8 minutes.

15. The method for producing the natural fiber felt according to claim 11, wherein the natural fibers in step a area combination of 90 wt % of linen fibers and 10 wt % of cotton fibers; and the fineness of the linen fibers ranges from 1.5 to 2.5 dtex, the length of the linen fibers ranges from 17 to 25 mm, the fineness of the cotton fibers ranges from 1 5 to 3 dtex, and the length of the cotton fibers ranges from 15 to 35 mm.

16. The method for producing the natural fiber felt according to claim 11, wherein the natural fibers in step a are a combination of 20 wt % of cotton fibers and 80 wt % of ramie fibers; and the fineness of the cotton fibers ranges from 1.5 to 2.5 dtex, the length of the cotton fibers ranges from 16 to 35 mm, the fineness of the ramie fibers ranges from 3 to 6 dtex, and the length of the ramie fibers ranges from 25 to 45 mm.

17. The method for producing the natural fiber felt according to claim 11, wherein the natural fibers in step a are 100 wt % of flax short fibers; and the fineness of the flax short fibers ranges from 0.15 to 0.25 dtex, and the length of the flax short fibers ranges from 17 to 25 mm.

Description

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0021] The present invention is further described below in combination with embodiments; however, it is not limited to these embodiments.

[0022] Unless otherwise specified, all raw materials used in the embodiments are commercially available industrial products which can be purchased through commercial channels.

Embodiment 1

[0023] Specific steps and processes of a natural fiber felt are as follows: [0024] a. treatment of raw material fibers: unpacking the raw material natural fibers, mixing and loosening the natural fibers, and then removing dust and impurities; the natural fibers are 100 wt % of flax short fibers, the fineness of which ranges from about 1.5 to 2.5 dtex, and the length ranges from 17 to 25 mm; [0025] b. forming a net: using a carding machine to carde the natural fibers obtained in step a at one time to obtain a natural fiber net; [0026] c. bonding the net to form a film: holding the natural fiber net obtained in step b by an anti-sticking net to pass through a spraying area, spraying a foam binder onto two opposite surfaces of the natural fiber net using a uniform spray head, and then extruding the sprayed film by a pressure roller to form the film; the foam binder is a mixture formed by stirring a binder, a foaming agent and water for 25 minutes, and every 100 parts by weight of foam binders contain 9 parts by weight of binders, 1 part by weight of foaming agent and the balance being water; and the binder is modified starch oxidized cross-linked starch, and the foaming agent is urea; [0027] d. drying and shaping: holding the film obtained in step c by a supporting net and transporting to a drying device, drying at the temperature of 150° C. for 0.8 min, and then shaping at the temperature of 160° C. for 0.6 min; [0028] e. waterproof treatment: spraying a water-repellent fruit wax emulsion onto the two opposite surfaces of the film obtained in step d; the fruit wax emulsion is a CFW-type fruit wax emulsion; and [0029] f. calendering finish, coiling and warehousing: performing calendaring finish to the film obtained in step e using a cold calender, then cutting to form coils, and warehousing to obtain the natural fiber felt, wherein a breadth of the coil is 200 cm, and length of each coil is 100 m.

[0030] The technical characteristics of the natural fiber felt prepared are as follows: a weight per unit area is 35 g/m.sup.2, a thickness is 0.28 mm, a tensile strength is 1458 N/m, a tear resistance is 72.8 N, a burst strength is 125.2 N, and a vertical permeation coefficient is 7.12×10.sup.−4 cm/s.

Embodiment 2

[0031] Specific steps and processes of a natural fiber felt are as follows:

[0032] While the present embodiment is basically the same as the embodiment 1, the differences are as follows:

[0033] The plant fibers used in step a are a combination of 90 wt % of linen fibers and 10 wt % of cotton fibers. The fineness of the linen fibers ranges from 1.5 to 2.5 dtex, the length of the linen fibers ranges from 17 to 25 mm, the fineness of the cotton fibers ranges from 1.5 to 3 dtex, and the length of the cotton fibers ranges from 15 to 35 mm.

[0034] For the foam binder used in step c, every 100 parts by weight of foam binders contain 10 parts by weight of binders, 2 part by weight of foaming agent and the balance being water. The binder is modified starch oxidized cross-linked starch, and the foaming agent is urea.

[0035] In step d, the film is dried at the temperature of 150° C. for 0.8 min, and then shaped at the temperature of 160° C. for 0.6 min.

[0036] The technical characteristics of the natural fiber felt prepared are as follows: a weight per unit area is 40 g/m.sup.2, a thickness is 0.32 mm, a tensile strength is 1358 N/m, a tear resistance is 70.9 N, a burst strength is 115.3 N, and a vertical permeation coefficient is 6.80×10.sup.−4 cm/s.

Embodiment 3

[0037] Specific steps and processes of a natural fiber felt are as follows:

[0038] While the present embodiment is basically the same as the embodiment 1, the differences are as follows:

[0039] The plant fibers used in step a are a combination of 80 wt % of ramie fibers and 20 wt % of cotton fibers. The fineness of the ramie fibers ranges from 3 to 6 dtex, the length of the ramie fibers ranges from 25 to 45 mm, the fineness of the cotton fibers ranges from 1.5 to 2.5 dtex, and the length of the cotton fibers ranges from 16 to 35 mm.

[0040] For the foam binder used in step c, every 100 parts by weight of foam binders contain 10 parts by weight of binders, 1 part by weight of foaming agent and the balance being water. The binder is modified starch oxidized cross-linked starch, and the foaming agent is urea.

[0041] In step d, the film is dried at the temperature of 150° C. for 1.0 min, and then shaped at the temperature of 160° C. for 0.8 min.

[0042] The technical characteristics of the natural fiber felt prepared are as follows: a weight per unit area is 40 g/m.sup.2, a thickness is 0.26 mm, a tensile strength is 1539 N/m, a tear resistance is 77.9N, the burst strength is 138.6 N, and a vertical permeation coefficient is 6.86×10.sup.−4 cm/s.