Claims
- 1. Fibrous structure in sheet form having the composition as follows:
- 10% to 90% by weight of pulp consisting essentially of cellulosic fibers cross-linked with formaldehyde, the predominant cross-linking being at the surface area of said fibers and in an amount sufficient to impart flexibility and softness to said fibers; and
- 90% to 10% by weight of an additional binding product, said amount being selected to ensure sufficient strength and cohesion to the structure of said sheet.
- 2. The fibrous structure according to claim 1 wherein the formaldehyde cross-linked cellulosic fibers are obtained by the spraying of a cross-linking reagent of formaldehyde as a mixture with hydrochloric acid and formic acid on individualized cellulose fibers; immediately after said spraying introducing said fibers which have said cross-linking reagent uniformly disposed thereon into an air stream having a temperature of from about 60.degree. to 250.degree. C. and a velocity of from about 1 to 20 m/sec during a curing time period ranging between from about 1 and 20 seconds to effect a cross-linking reaction, and separating the fibers from said air stream.
- 3. Fibrous structure according to claim 2 wherein said additional binding product consists essentially of non-cross-linked cellulosic fibers.
- 4. Fibrous structure according to claim 3 in the form of a sheet of a specific surface weight less than 40 g/m.sup.2 and wherein 15% to 30% by weight of a pulp of said cross-linked cellulosic fibers were obtained by said process wherein the proportion of formaldehyde to said fibers on a weight basis is between 1.3 and 2.1%; and 85% to 70% by weight of a pulp of non-cross-linked cellulosic fiber selected from the group consisting of bisulfite pulp, a "Kraft" pulp, a pulp of deciduous growths, or a mixture thereof.
- 5. Fibrous structure according to claim 4 wherein said composition includes 20% by weight of a pulp of said cross-linked cellulosic fibers.
- 6. Fibrous structure according to claim 2 in the form of a sheet with a specific surface weight between 40 and 100 g/m.sup.2, and wherein 15% to 40% by weight of a pulp of said cross-linked cellulosic fibers were obtained by said process, wherein the proportion of formaldehyde to said fibers on a weight basis is between 1.3 and 2.1%; and 85% to 60% by weight of a pulp of non-cross-linked cellulosic fibers selected from the group consisting of bisulfite pulp fibers, a "Kraft" pulp fiber, and deciduous growths pulp fibers, or a mixture thereof.
- 7. Fibrous structure according to claim 6 wherein said composition includes 25% by weight of a pulp of said cross-linked cellulosic fibers.
- 8. Fibrous structure according to claim 2 wherein the additional binding product includes synthetic fibers.
- 9. Fibrous structure according to claim 8 wherein said composition comprises 65% to 85% by weight of a pulp of said cross-linked cellulosic fibers, the proportion of formaldehyde to said fibers on a weight basis being between 0.6 and 2.6%; and 35% to 15% of synthetic pulp fibers.
- 10. Fibrous structure according to claim 9 wherein said synthetic fibers are low-density polyethylene fibers.
- 11. Fibrous structure according to claim 2 wherein the additional binding product includes a mixture of non-cross-linked cellulosic fibers and of synthetic fibers.
- 12. Fibrous structure according to claim 11 wherein said composition includes 20% to 40% by weight of a pulp of said cross-linked cellulosic fibers, the proportion of formaldehyde to said fibers on a weight basis being between 1.3 and 2.1%; 30% to 70% by weight of a pulp of non-cross-linked cellulosic fibers; and 10% to 30% by weight of synthetic fibers.
- 13. Fibrous structure according to claim 12 wherein said composition includes 30% by weight of a pulp of said cross-linked cellulosic fibers, the proportion of formaldehyde to said fibers on a weight basis being between 1.3% and 2.1%; 55% by weight of a pulp of non-cross-linked cellulosic fibers; and 15% by weight of a pulp of synthetic fibers.
- 14. Fibrous structure according to claim 2 wherein the additional binding product includes a binder printed on the surface of the sheet.
- 15. Fibrous structure according to claim 14 wherein the printed binder is photogravure consisting of a deformed hexagonal pattern of which the greatest length is parallel to the transverse direction of the machine, and the binder is a latex.
- 16. Fibrous structure according to claim 15 in the form of a sheet of specific surface weight less than 40 g/m.sup.2 wherein the percentage in weight of the binder in the structure is between 3 and 20%.
- 17. Fibrous structure according to claim 15 in the form of a sheet of specific surface weight between 40 g/m.sup.2 and 100 g/m.sup.2 wherein the percentage of binder in the structure is between 3 and 20%.
- 18. Fibrous structure according to claim 2 wherein the additional binding product includes a binder incorporated into the material.
- 19. Fibrous structure according to claim 18 in the form of a sheet with a specific surface density less than 40 g/m.sup.2 wherein the percentage in weight of the binder in the structure is between 5 and 25%.
- 20. Fibrous structure according to claim 18 in the form of a sheet with a specific surface weight between 40 g/m.sup.2 and 100 g/m.sup.2 wherein the percentage in weight of the binder in the structure is between 10 and 35%.
- 21. Fibrous structure according to claim 18 wherein the binder incorporated into the material is an acrylic latex.
- 22. A process for making fibrous structures with compositions defined in claim 14 characterized by the following stages in combination: forming a continuous sheet on a papermaking machine; and printing a binder on the sheet at a speed essentially equal to the speed of the sheet at the machine's output.
- 23. A process for making fibrous structures according to claim 22 wherein the speed of the papermaking machine is between 500 and 1,000 meters a minute.
Priority Claims (2)
Number |
Date |
Country |
Kind |
75 31965 |
Oct 1975 |
FRX |
|
78 22657 |
Aug 1978 |
FRX |
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RELATED CASES
This application is a continuation-in-part of application Ser. No. 731,895 filed Oct. 13, 1976, now U.S. Pat. No. 4,113,936 issued on Sept. 12, 1978, entitled "Cross-Linking Of Cellulose Fibers In Gas Suspension"; and is related to application Ser. No. 940,189 filed Sept. 7, 1978 entitled "Improved Cross-Linked Cellulose Fibers," which in turn is a continuation-in-part of application Ser. No. 731,895.
US Referenced Citations (12)
Non-Patent Literature Citations (1)
Entry |
Chemical Abstracts, vol. 82, No. 14, Apr. 7, 1975, p. 87968M. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
731895 |
Oct 1976 |
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