DE1218871B - Process for the wet production of paper-like structures consisting at least partially of synthetic fibers - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. α .:

D21h

German class: 55f-16

Number: 1218 871

File number: S 78514 VI b / 55 f

Filing date: March 15, 1962

Opening day: June 8, 1966

The invention relates to a method for producing at least some of synthetic fibers existing paper-like structures on the wet route, the synthetic fibers with a aqueous solution of a dispersing aid based on polymers are pretreated.

Under paper-like structures are web-like or sheet-like materials to understand that with the Usual means of paper technology can be produced. For the production of these structures With any high content of synthetic fibers there is a homogeneous distribution of the in and of itself poorly wettable fiber material required in the water; the homogeneous distribution is made by coating of the fibers achieved with a dispersant.

Various cation-active and anion-active dispersing aids have already been used for this purpose suggested. Water-soluble dispersants based on polymers are also known, e.g. B. Cellulose ether, carboxymethyl cellulose (German Auslegeschrift 1150 865), partially hydrolyzed polyvinyl acetate, Polyacrylic acid (German Auslegeschrift 1144 580), certain polyoxyethylene compounds Structure and similar materials.

A great difficulty in the production of paper-like structures that contain synthetic fibers, is that the synthetic fibers rapidly coherent in the preparation of the aqueous suspension Form flakes. This has an adverse effect on the formation of leaves or webs. at Use of unsuitable agents can cause disruptive foam formation.

The object of the invention is a method for producing the paper-like ones described above Structure with at least a part of synthetic fibers, in which the difficulties described avoided and the production of paper-like structures of high quality in a simple manner on an industrial scale Base is possible.

The method according to the invention is characterized in that the fibers with an aqueous Solution of N-ethoxylated polyamides, especially those of N-ethoxylated polycapronamides or N-ethoxylated mixed polyamides from C-aminocaprolactam and the salt of hexamethylenediamine and adipic acid.

According to a particular embodiment of the method, the fibers are pre-treated with a 1- to 2.5 ° / ₀ aqueous solution of the N-ethoxylated polyamide.

The invention also relates to the paper-like structures produced in this way, the partial process for producing at least
partly made of synthetic fibers
paper-like structures on a wet path

Applicant:

Societe de la Viscose Suisse,
Emmenbrücke (Switzerland)

Representative:

Dr. E. Wiegand and Dipl.-Ing. W. Niemann,

Patent Attorneys, Munich 15, Nussbaumstr. 10

Named as inventor:

Dr. Bruno Stefan Vladimir Marek,

Josef Gneisz, Emmenbrücke (Switzerland)

Claimed priority:

Switzerland of March 15, 1961 (3133)

wisely or exclusively consist of synthetic fibers.

The production of N-ethoxylated polyamides is known. It is also known that certain substituted Polyamides can be water soluble.

In contrast, the invention is based on the knowledge that water-soluble N-ethoxylated polyamides when used to disperse synthetic fibers in the manufacture of said paper-like ones Formed products of special quality result. The application of these compounds is not immediately obvious, since aqueous suspensions are not homogeneous with all dispersants made of synthetic fibers that remain stable enough to become paper-like Formed with even fiber distribution and with a low to exclusive content of synthetic To have fibers processed.

For example, according to the invention, the N-ethoxylated derivative of the mixed polyamide of 60 ° / ₀ C aminocaprolactam and 40% hexamethylenediamine adipic acid salt and the N-ethoxylated derivative of polycapronamide can be used to prepare the suspension of the synthetic fibers in water. These compounds have good solubility in water, with both the speed of the dissolution process and the solubility

609 578/458

3 4

maximum solution concentration can be understood. NOSIC «short fibers, as they are in» rayon rayon and

As has been shown, the above-mentioned N-ethoxy-other chemical fibers ”, 9 (1959), p. 431, are described

lated polyamides are both on polyamide and on, and other short viscose fibers are used

Sufficiently absorbed polyester fibers, regardless of the fact, can, for example, by means of the described

of whether it after coating the fibers with dispersants 5 up to 70 ° / ₀ polyamide or poly-

N-ethoxylated polyamide and, after their separation, ester fibers are added to the aqueous dispersion

of the aqueous solution at room temperature or to make a sheet with the appropriate content

Dried at a higher temperature or directly attached to synthetic fibers and special properties

will be working. to manufacture. With ground cellulose and rag

Synthetic fibers made with the above-mentioned dispersible cellulose can, for example, be paper-like structures

Treated with lubricants, result in uniform with 90% content of the mentioned synthetic

aqueous suspensions that are very little made to flake fibers. A sheet in this

tend to form and is readily produced to produce species, shows an even distribution

paper-like structures can be used. of the fibers, such as this when viewing, among other things

With N-ethoxylated polyamide, for example, the finished papers can be checked through

wise the following fibers are dispersed: polyamide can. Papers made from fiber dispersions made with

fibers such as polycapronamide, the polyamide produced by unsuitable dispersants,

eo-aminoundecanoic acid, polyhexamethylene adipic acid- were obtained, show unequal-

amide, polyhexamethylene febacic acid amide, in general fiber distribution.

my condensation products of dicarboxylic acids ao The invention is hereinafter based on

explained in more detail with an aliphatic alicyclic or aromatic examples,

see diamine; Polymers of urethanes; Polyester. .

fibers, such as polyalkylene terephthalate, copolymer Example 1

from terephthalate-isophthalate and ethylene glycol, an ethoxylated copolymer is made

Polyvinyl acetate, copolymers of vinyl chloride 25 60% ε-aminocaprolactam and 40% hexamethylene

and vinyl acetate, from vinylidenecyanide and vinyl diamine adipate with a nitrogen content of 2.4% N,

acetate, made from acrylonitrile and vinyl acetate; Polyacrylic which has a degree of ethoxylation of 10.5 mol of ethylene

nitrile fibers, such as a copolymer of vinyl chloride oxide, corresponds to per gram atom of nitrogen,

and acrylonitrile; Polytetrafiuoräthylenfäuren od. Like. Which dissolves to 25 to 30% in water and thereby

Synthetic fibers in the present 30 have a viscosity of 1.6 cP in 2% aqueous solution

Relationship between the spun out of nozzles at 20 ^° C. shows. It softens at 135 ^° C. and melts

nen fibers as well as not spun from nozzles, at 140 ⁰ C.

for example by precipitation from solutions Fibers, understand. fibers 3 denier / 6 mm and polyester short fibers 1.5 denier /

For the absorption of the N-ethoxylated polyamides at 35 4 mm with the ethoxylated mixed die described synthetic fibers, these are preferably polyamide, the fibers were first made by Vormit 10 to 25 g of N-ethoxylated polyamide per liter of treatment applied products treated with out water at a slightly elevated temperature. wash with soda water and then exempt

The application of the N-ethoxylated polyamides to the centrifuged or, after the aqueous has been separated off, the synthetic fibers can be ^{dried at 65 °} C. for 2 hours in any suitable solution. In both production stages of the synthetic fibers, as they are the cases, the two types of fibers can be wetted very well in water for processing on the paper machine, as can be achieved by the rapid sinking of the suitable ones. The manipulation of the spun fibers when immersing them in water is shown. After stirring the slurry with synthetic fibers with N-ethoxylated polyamides, very even suspensions which are largely stable against flaking and cut into short fibers or immediately before formation can result during spinning, before stretching, before or after.
the entry into the fabric. If the synthe-. .
fibers are already being used with other products.
If necessary, an N-ethoxylated polycaproone removal can be achieved, mostly by washing with soda-amide with an N content of 2.68%, which is a warm water containing it. Degree of ethoxylation of 9 moles of ethylene oxide per gram

Particularly important for the production of paper- atomic nitrogen corresponds. The product shows in

like structures is the possibility of the content of the 2% aqueous solution a viscosity of 1.6 cP

synthetic fibers in the mixture with others at 20 ⁰ C and has a F. of 151 ° C. According to the

Fibers can be varied within wide limits, as this results in absorption of this N-ethoxylated polycapronamide

Papers each desired special own from the fibers mentioned in Example 1 in the loading

properties can be produced. According to the type written, they show good wettability and

The aqueous fiber suspension required for this can be homogeneously distributed in water and thus the same

sions are produced as follows: Behavior as with the described N-ethoxy-

The fibers pretreated with N-ethoxylated polyamide as described above,

tem polyamide covered, synthetic fibers. .

can z. B. in a manufactured in a known manner Example 5

presented suspension of cellulose fibers entered in this example as a starting product

whereupon from it finally on the paper - not spun through nozzles, but precipitated

machine uses a sheet of sufficient strength in the 65 fibers, a type of so-called fibrid.

The wet state is formed, which is further transformed into paper. Moist polyester fibrids, as for example in the

can be worked. If in such a paper French patent 1 214 126 are described,

production as a cellulose component, so-called »POLY- corresponding to 100 g dry substance, are used in the

ten-fold amount of a 2 ° / ₀ solution of N-ethoxylated caproamide according to Example 2, stirred at 35 ⁰ C for 40 minutes, suction filtered and at room temperature over P ₂ O ₅ dried for 48 hours. In the same way, 100 g of dry substance of the same fibrids are treated only with water and dried. The fibrids treated with N-ethoxylated capronamide can be dispersed homogeneously in a short time after 48 hours of sharp drying and subsequent moistening with water. The fibrids treated with water are only sparsely wetted by water and, if they are homogeneously distributed, require significantly longer mechanical stress in the water. After distribution in the water, leaves of about 100 g / m ^{a are} made from both batches in a sheet-forming apparatus. The sheet made from treated fibrids has a higher water retention capacity than that made from fibrids that have not been pretreated with N-ethoxylated polyamide.

Example 4

So-called "polynosic" short fibers, 0.4 denier / 4 mm, are ground in a Hollander to 42 ⁰ SR. 0.36 kg (30%) thereof are suspended in 60 liters of water in a mixing vat by distributing with a paddle stirrer for 15 minutes. A further 40 liters of water and a proportion of 0.48 kg (40%) short viscose fibers, 1.5 denier / 4 mm, are then added and the mixture is stirred for 10 minutes. 100 liters of water and, at the same time, 0.36 kg (30%) of polyamide fibers, 3 den / 6 mm, with 10 g / l of the N-ethoxylated mixed polyamide described in Example 1 in a liquor ratio of 1:20 are added for half an hour Treated at 40 ⁰ C, then centrifuged off and ^{dried at 90 to 105 0} C, added. A sheet is produced from the stable suspension on a Fourdrinier machine with a screen width of 40 cm. After drying on a padder, this structure can be impregnated with resins, dried, pressed and ^{calendered at 150 to 180 °} C. between metal and paper rolls. In this way, papers are produced with excellent properties and with even fiber distribution, as can be seen from the inspection.

Example 5

In a mixing vat, 660 g of aspen sulphite pulp and 180 g of fibrillated rag cellulose are whipped well in 100 liters of water. A proportion of 360 g of polyhexamethylene adipamide (2 denier / 4 mm) are added to the fiber suspension with stirring. The polyamide fiber, before addition to the cellulose pulp with a solution of 10 g / l of an ethoxylated PoIycapronamids (degree of substitution nine Äthoxyreste per gram atom of N) at 45 ⁰ C for 30 minutes, centrifuged and dried in the air. After the mixing vat has been filled to 2001, the fiber suspension is processed into a uniform paper-like sheet at a consistency of 0.2 to 0.3% on a Fourdrinier machine with a wire width of 40 cm. The transparency of a paper produced in this way is significantly better than that of a paper produced with an additive other than the wetting agents according to the invention. On the Fourdrinier machine, there was no disruptive foam formation and no sticking to the wet or dry section.

Claims (2)

Patent claims: 1. A process for the production of paper-like materials consisting at least partially of synthetic fibers Formed by the wet route, the synthetic fibers with an aqueous solution of a Polymer-based dispersing aids are pretreated, characterized in that that the fibers with an aqueous solution of N-ethoxylated polyamides, especially those of N-ethoxylated polycaproamide or N-ethoxylated mixed polyamides C-aminocaproolactam and the salt of hexamethylenediamine and adipic acid. 2. The method according to claim 1, characterized in that the fibers with a 1- to 2.5% strength aqueous solution of the N-ethoxylated polyamide are pretreated. Considered publications:
German Auslegeschriften No. 1150865, 1144580