DE1129451B - Process to improve the colorability of heat-treated polyvinyl alcohol threads - Google Patents

Description

GERMAN

PATENT OFFICE

kl. 8 m 12

INTERNATIONALK KL.

D06p; m

K 38192 IVc / 8m

REGISTRATION DATE: JULY 13, 1959

NOTICE THE REGISTRATION ANDOUTPUTE

EXPANDED MAY 17, 1962

It is known that threads made of polymers containing hydroxyl groups, such as polyvinyl alcohol, or from hydrolyzed copolymers of vinyl esters with smaller amounts of polymerizable Vinyl or vinylidene compounds by dry or wet spinning from their aqueous ones Solutions can be made. However, these threads are characterized by an inexpedient Sensitivity to water and especially to hot water.

To avoid these disadvantages, the freshly spun threads are usually subjected to a heat treatment at a temperature of 200 to 250 ° C and then acetalized with formaldehyde. The moisture softening temperature, ie the temperature at which the threads shrink by 10% of their original length when they Immersed in water for 30 minutes can be increased to 60 to 100 ° C by the heat treatment. When the fiber is formalized after the heat treatment, their Feuchterweichungstemperatur is increased to 100 to 130 ⁰ C, so that it itself is not dissolved in 150 ° C hot water. The wet heat resistance of the fiber thus treated is sufficient for practical purposes.

On the other hand, the heat-treated and formalized polyvinyl alcohol threads have a disadvantage low dyeability. Since polyvinyl alcohol threads do not contain basic nitrogen, you can use most acid dyes and acid mordant dyes are not colored. You will be from some of these dyes only weakly stained. Untreated polyvinyl alcohol threads can almost have the same dyeability as cellulose fibers because they contain hydroxyl groups, however After the heat treatment, the accessible hydroxyl groups of these molecules are less, so that the Affinity of these threads for direct dyes is lower. Further, when the heat-treated polyvinyl alcohol threads are acetalysed with formaldehyde, the dyeability is usually reduced even further, because the remaining accessible hydroxyl groups of the polyvinyl alcohol molecules after the heat treatment are practically blocked by the formaldehyde. The dye absorption capacity of the heat-treated and then formalized Polyvinyl alcohol threads are therefore usually only about when using direct dyes 30 to 80% of the dye absorption capacity of cotton fibers.

If polyvinyl alcohol threads directly after spinning in aqueous solution a partial Process for improvement

the dyeability of heat-treated

Polyvinyl alcohol threads

Applicant:

Kurashiki Rayon Company Limited, Kurashiki (Japan)

Representative: Dr.-Ing. H. Ruschke,

Berlin-Grunewald, Auguste-Viktoria-Str. 65,

and Dipl.-Ing. K. Grentzenberg, Munich 27,

Patent attorneys

Claimed Priority: Japan July 14, 1958 (No. 19 741)

Yasuji Ohno and Kenichi Tanabe, Kurashiki (Japan), have been named as inventors

Formalization without being subjected to an intermediate heat treatment, the affinity is too direct dyes well. This is due to the large increase in the accessible hydroxyl groups through the Attributed to swelling of the fibers during formalization. This effect outweighs the blocking of accessible hydroxyl groups through the formalization, so that the total amount of accessible Hydroxyl groups considerably exceeds that of fibers that prior to formalization have been heat treated. If the formalization is carried out too much, it lowers the affinity for direct dyes until the threads are no longer colored but only slightly colored can be.

In order to improve the dyeing properties of polyvinyl alcohol fibers, "animalization" - Processes have been developed in which, for. B. by acetalizing the fiber with amino aldehydes, the one contain primary or secondary amino group, basic nitrogen groups are introduced into the fiber will. Furthermore, a mixed spinning process has been developed in which the fiber is made from a spinning solution is spun, which is a mixture of partially amino-acetalized polyvinyl alcohol and non-

209 580/390

contains polyvinyl alcohol. The spun fiber is then heat treated and acetalized.

The animalized fibers which contain weakly basic amino radicals can then according to the usual Processes are colored, but in the presence of alkali the affinity for dyes, especially to direct dyes, lose. Even if the fibers have been dyed with acidic dyes, a discoloration occurs after treatment with alkali.

According to the invention, a method for improving the dyeability is proposed in which the animalized threads do not lose their affinity for dyes on alkaline treatment, namely by acetalizing the spun threads with a compound that is an aldehyde and also a quaternary Contains ammonium group.

It is known that quaternary ammonium salts differ in their chemical behavior very significantly from the amine salts. When the salts of amines are treated with strong bases such as sodium hydroxide, they are cleaved to form the free amines. However, the quaternary ammonium salts do not react with strong alkalis, such as potassium hydroxide, in aqueous solution. This is due to the complete dissociation of quaternary ^{ammonium hydroxide into ions, namely in = N +} and -OH ", in aqueous solution, so that in water it has the same base strength as sodium or potassium hydroxide.

Therefore, if a fiber is acetalized with a weakly basic amino aldehyde, it can do so weak base with the acidic dye formed amine salt are cleaved by alkalis, whereas in the acetalization of the fiber with the quaternary ammonium compound, the strongly basic one Quaternary ammonium salt forms a unit with the acidic dye, which is not attacked by the alkalis will. Since the quaternary ammonium compound also has the basic property in the presence of Retaining alkali, fibers containing quaternary ammonium ions lose, even in the presence of Alkali does not have their affinity for direct dyes. To introduce the quaternary ammonium group amine, substituted hydrazines and semicarbazides, which are easily cleaved in the aldehyde can be.

X is an anion, ζ. B. a hydroxyl, bromide, chloride, iodide, methyl sulfate or sulfate ion.

Compounds which contain the following cationic groups are illustrative examples of compounds which can be used successfully in the process according to the invention: (Formylmethyl) -trimethylammonium (FormylmethylJ-cyclohexyldimethylammonium (formylmethyl) -diethylmethylammonium (formylmethyl) -dibutylmethylammonium (formylmethylamethyl) -dipionium (formylmethyl) Formylmethyl) ethyldimethylammonium (formylmethyl) benzyldimethylammonium (formylmethyl) methylpiperidinium (2-formylethyl) trimethylammonium (2-formylethyl) cyclohexyldimethylammonium (2-formylethyl) -benzyldimethylammonium (2-formylethyl) -diethylmethyl-formylethylammonium (2-formylethyl) (2-formylethyl) -diethyl-formylammylethyl (2) ethyl-formylammyl-ethylammonium 2-formylethyl) -benzyldimethylammonium (2-formylethyl) -methylpiperidinium (2-formylpropyl) -trimethylammonium ^ -Formylpropyl ^ -cyclohexyldimethylammonium (2-formylpropyl) -benzyldimethylammonium (3-formylammylpropyl-2-trimethylammonium -l-methylpyridinium
3-formyl-1-methylpyridinium
4-formyl-1-methylpyridinium
(p-Formylphenyl) -trimethylammonium (o-Formylphenyl) -trimethylammonium bis- (formylmethyl) -dimethylammonium bis- (formylmethyl) -benzylmethylammonium bis- (formylmethyl) -ethylmethylammonium bis- (2-formylethyl) -dimethylammonium bis- ) -benzylmethylammonium (1,3-diformylpropyl) -trimethylammonium The acetalization of the polyvinyl alcohol thread with the aldehyde or the aldehyde parent substance, which contains a quaternary ammonium group, takes place

with an acid catalyst according to a customary in the polyvinyl alcohol yarn ₄₅ are quaternary acetalization. The partial acetalization of ammonium compounds of the following formula with a quaternary ammonium group ent

applies:

Ri

^Rz A

R ₃ /
A ₁

Ri

and

^ N ⁺ X "

In these formulas, R ₁ , R ₂ and R _{3 are} alkyl, aralkyl or cycloalkyl radicals or alkylene groups which, together with the nitrogen atom, form part of a heterocyclic ring, e.g. B. a pyridine or piperidine ring.

A ₁ and A ₂ are organic radicals which contain an aldehyde group. This also includes compounds which can be hydrolyzed to aldehydes in situ, ie aldehyde parent substances such as acetals and hemiacetals of aldehydes. The aldehydes can preferably be used in the form of their acetals because acetals are more stable than free aldehydes. It is also possible, the addition products of aldehydes with compounds such as sodium bisulfite, hydroxyl-containing aldehyde can be followed by acetalization with another aldehyde, such as formaldehyde, which is commonly used for acetalization, resulting in a product with superior coloring properties and also with good heat resistance dry and moist condition is obtained.

The present invention is further illustrated by the following examples in which - unless otherwise indicated - parts are parts by weight and the degree of acetalization in percent of the acetalized hydroxyl groups, based on the total number of original hydroxyl groups.

example 1

A polyvinyl alcohol yarn, which was produced by a conventional spinning method was heat-treated for 3 minutes train at a temperature of 22O ⁰ C. The thread was then treated in a bath at a temperature of 70 ° C for 1 hour, which was composed of an aqueous solution of 1.5% (1-methyl-S ^ -dimethoxypropyty-trimethylammonium-

iodide, 17% sulfuric acid and 15% sodium sulfate. The thread obtained contained 0.2% nitrogen. It showed superior dyeability with acidic direct dyes. When using this thread before dyeing is pretreated with a 2% caustic soda solution, there will be no noticeable influence on the dye absorption capacity established. If, on the other hand, a polyvinyl alcohol thread with a weakly basic Aminoaldehyde has been acetalized, pretreated with a 2% caustic soda solution before dyeing becomes, the dyeability with acidic direct dyes as a result of the alkali treatment becomes considerably reduced.

Example 2 ^X 5

A polyvinyl alcohol thread produced by a conventional spinning process was made according to the im Example 1 heat-treated method under tension at a temperature of 220 ° C for 3 minutes. The thread was then treated in a bath made up of an aqueous solution of 2.3% (3,3-dimethoxypropyl) cyclohexyldimethylammonium sulfate duration. The thread thus obtained contained 0.21% nitrogen. It showed superior staining properties for acidic and direct dyes. If this thread z. B. was stained with an acid dye, it absorbed completely the dye in the dye bath. Even if the colored material is in an aqueous solution, containing 2% sodium carbonate was immersed, most of the dye remained firmly on the fiber. In contrast, if the same polyvinyl alcohol thread with a weakly basic amino aldehyde acetalized, dyed with the same dye and then dipped in a solution of 2% sodium carbonate almost all of the dye is drawn out.

Example 3

A polyvinyl alcohol thread produced by a conventional wet spinning method became 10 mm long Pieces cut up, which are then heat-treated in air for 10 minutes at a temperature of 210 ° C became. The thread was then treated for 2.5 hours at 70 ° C. in a bath consisting of an aqueous Solution of (2,2-diethoxyethyl) trimethylammonium hydroxide, 20% sulfuric acid and 15% sodium sulfate duration. The thread thus obtained contained 0.18% nitrogen.

This thread was then heated to 60 ° C for 1 hour in a bath containing 3% formaldehyde, 1.2% sulfuric acid and contained 15% sodium sulfate. It was resistant to boiling water and had as already described in Examples 1 and 2, also excellent coloring properties and color fastness.

Example 4

A polyvinyl alcohol thread obtained by a conventional spinning process was, as described in Example 1, heat-treated for 3 minutes with tension at a temperature of 220 ° C. in air. The thread was then treated for 2 hours at 70 ^° C. in a bath which consisted of an aqueous solution of 2% bis- (3,3-dimethoxypropyl) -dimethylammonium chloride, 20% sulfuric acid and 15% sodium sulfate. It then contained 0.85% nitrogen and showed superior heat resistance in the moist state, had excellent coloring properties and also - as already indicated in the above examples - color fastness to alkali.

Example 5

A polyvinyl alcohol thread produced by a conventional dry spinning process was stretched in 1 second to 3.5 times the original length in Wood's alloy at 210 ^° C. and then again in 1 second by the original length in Wood's alloy at 220 ^{° C.} It was then heated for 1 hour in a bath at 6O ⁰ C, which consisted of 15% sulfuric acid and 15% sodium sulfate from an aqueous solution of 0.6% (p-formylphenyl) -trimethylammoniumjodid. It then contained 0.45% nitrogen.

The yarn was then heated in a bath 20 minutes 6O ⁰ C, was the% from an aqueous solution of 2 sulfuric acid, 10% sodium sulfate and 2% terephthalaldehyde.

It was now resistant to boiling water and had excellent coloring properties. if he in a dyebath of an aqueous solution of an acidic dye and 10% of a 28% ammonia solution was immersed, the fiber absorbed most of the dye. If, on the other hand, a subjected to the same treatment fiber acetalized with a weakly basic aminoaldehyde no absorption of the dye could be observed.

Claims (2)

PATENT CLAIMS: 1. A process for improving the dyeability of heat-treated polyvinyl alcohol thread, characterized in that it is treated with an aqueous solution containing an acid catalyst and a compound of the formula R. Λ N ⁺ X " or ^ N- ¹ Rs / A ₁ contains, treated, in which R ₁ , R ₂ and R _{3 are} alkyl, aralkyl or cycloalkyl radicals or alkylene groups which together with the nitrogen atom form part of a heterocyclic ring, and A ₁ and A _{2 are} organic radicals which are an aldehyde group or contain a group which splits off an aldehyde group under the present conditions. 2. The method according to claim 1, characterized in that according to claim 1 partially Then acetalized threads with an aldehyde without quaternary ammonium groups acetalized. © 209 580/390 5.62