Process of making and treating cellulose fibers or yarns with a

Details Process of making and treating cellulose fibers or yarns with a Process of making and treating cellulose fibers or yarns with a

1997-07-01

2000-04-11

Tentoni, Leo B.

Plastic and nonmetallic article shaping or treating: processes

With printing or coating of workpiece

811551, 81161, 8120, 8196, 26417124, 264187, 264211, 264233, 427387, 427392, D01F 202, D06M 15356

Patent

active

060484799

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

The invention relates to cellulose fibers or yarns with a reduced tendency to form fibrils and a process for manufacturing such fibers or yarns, whereby the fibers are preferably produced according to the NMMO filament formation process.
Cellulose fibers and yarns have long been known. The most important classic production processes are the so-called cuprammonium process and the viscose process.
It has also long been known how to dissolve cellulose polymers in an amine oxide of a tertiary amine, if necessary in the presence of water, and to produce from these solutions, by means of pressing through nozzle tools, formed objects such as fibers, filaments, yarns, films, and the like. Processes using N-methylmorpholine-N-oxide have turned out to be particularly suitable; economical interests and development efforts are centered on those processes. Processes for the production of such formed objects using N-methylmorpholine-N-oxide, in the following called NMMO processes, essentially consist in that, first, a suspension is produced from cellulose such as cotton linters, chemical wood pulp and the like, water and NMMO and in that this suspension is transformed into a solution by heating and removing a portion of the water.
This solution is then filtered and extruded through a nozzle into a mostly aqueous coagulation bath, preferably with an interim air gap, whereby the formed objects such as filaments, yarns, films and the like are formed via coagulation. These formed objects are then washed to remove any tertiary amine oxide still present. Subsequently the formed object can be dried and further processed in the customary manner, e.g. wound up, etc.
Compared to the classic processes for manufacturing cellulose formed objects, the NMMO process is in particular characterized in that it involves essentially physical phenomena, so that at least in theory no chemical reactions take place and no chemical byproducts are formed which must be disposed of as waste products or transformed back by chemical methods into the initial substances. The NMMO process therefore fundamentally ranks among the very environmentally friendly processes. Additionally the actual initial substance is a raw material which grows back, and the cellulose final product is highly biodegradable.
However, it has been shown that the cellulose fibers, especially those which are produced according to the NMMO process, exhibit a tendency to form fibrils, in particular in a wet state, especially if mechanical forces act on the fibers. This happens in the case of dyeing, among others, as well as during washing of the fibers, when after leaving the coagulation bath the solvent still present on the fibers is to be removed. Naturally, in all further processing steps the existing fibrils will be more or less conspicuous, in the dried state as well.
Dust is increasingly formed, and fine fibrils break off and roll together in curl fashion. Entire fibrils may even break off.
It may be true that the formation of fibrils can be useful in creating special surface effects, but for most applications fibrils are not desired.
Efforts have been undertaken to counteract the disadvantages of fibril formation in that e.g. dyed fabrics are treated with commercial cellulose cross-linking agents which have low formaldehyde content. By doing so the formation of fibrils in the fabric is reduced, although the rougher texture that the fabric exhibits must be tolerated.
Besides other disadvantages, a corresponding cross-linking prior to dyeing has the consequence that the dye receptivity is considerably reduced.
One further process for reducing the formation of fibrils is described in the international patent application WO 92-07124. This process consists essentially in that the cellulose fibers, which are not yet dried, are treated with an aqueous solution or dispersion of a polymer possessing a plurality of cationic groups. Since these polymers can be washed out very easily, it is recommended to also use a cross-linking agent, especially together wit

REFERENCES:
patent: 3952134 (1976-04-01), Watson
patent: 4128675 (1978-12-01), Rossler et al.
patent: 5520869 (1996-05-01), Taylor
patent: 5593483 (1997-01-01), Brunken
Lewin, Menachem and Stephen B. Sello. Handbook of Fiber Science and Technology: Vol. II: Chemical Processing of Fibers and Fabrics: Functional Finishes Part B, Chapters 1 and 2. (pp. 16-327) (Undated).
Abstract of Japan 52-91,993 (Published Aug. 2, 1977).
"Textil und Silikone, Weichmacher und Elastomere,"Wacker Chemie GmbH Brochure, (No. 4696.3/93(8) 90, pp. 10 and 14 (undated).
Dannhorn, Bernd. "Der Einflu.beta. der Ausrustung mit Vernetzern und Additiven bei Artikeln aus Lyocellfasern," Lenzinger Berichte, No. 9 Sep. 1994, Lenzing, Austria, pp. 73-80.
Welch, Clark. "High Speed Crosslinking: Durable Press Finishing Without Formaldehyde," Textile Chemist and Colorist, vol. 22 No. 5 May 1990, pp. 13-16.
Sello, Stephen. "Functional Finishes for Natural and Synthetic Fibers," Journal of Applied Polymer Science, Applied Polymer Symposium 31 (1977), pp.229-249.
Mark, H, Norman S. Wooding and Sheldon M. Atlas. Chemical Aftertreatment of Textiles, (1971), Chapter V: "In Situ Formation of Polymers.".
Textilveredelung 20, No. 1 (1985), pp.8-12.

Affiliated with

Also associated with

Rating

Process of making and treating cellulose fibers or yarns with a does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process of making and treating cellulose fibers or yarns with a , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process of making and treating cellulose fibers or yarns with a will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1174231