DE1669418B2 - - Google Patents

Description

O NH-R

or

CH ₃

NH,

NaO ₃ S

-NH- '

IO

OR ₂
wherein R is hydrogen, methyl or the group

CH ₃

R _{1 is} hydrogen or the —SO ₃ Na group and R _{2 is} hydrogen, the group

means where A is a bivalent linear or branched one Alkylresl is, in a part of the polyamide, homogeneously imparted to a dye concentrate, this dye concentrate mixed with the main amount of the polyamide and then this mass melt spinning.

2. The method according to claim i, characterized in that 0.1 to 20 percent by weight of Concentrate, based on the total amount of the mass to be spun, is added.

The invention relates to a process for spin-dyeing by the melt-spinning process manufactured molded structures from linear, synthetic polyamides.

Lis is known to have synthetic polyamides in bulk to be colored using inorganic or organic dyes or pigments. Conditional Due to the high melting temperature of the polyamides, the choice of dyes is very limited. A number of metal complexes win azo dyes !! and phthalocyanine metal complexes have already been proposed been. However, let durability wedge. Lightfastness and depth of color leave a lot to be desired, as with some Dyes show an increasing sensitivity with increasing concentration. From inorganic Color pigments can practically only be used for spin dyeing ultramarine, cadmium sulfide, iron oxide and chromium oxide can be considered, usually polyamide chips by treatment with dye solutions or dyestuff dispersions and, after drying, by the Schnielz spinning process spun into threads. In this process there is no continuity and at the same time there is a increased expenditure on equipment required.

In French patent specification 1,149,967 it is mentioned that brominated anthraquinone disulfonic acids suitable for dyeing artificial nitrogenous fibers. However, from this information cannot be concluded that the polyamide dye concentrates according to the invention, their dyes not with are identical to those described in French patent specification 1,149,967, are surprisingly improved Results, especially with regard to the stability of the dyes, under the extreme conditions melt extrusion.

There has now been described a method of spin-dyeing molded articles made by the melt-spinning process Formed from linear, synthetic polyamides by anthraquinone dyes soluble in polyamide found, which is characterized by. that one anthraquinone dyes of the formula

O NH-R

40

ö R ₂

wherein R is hydrogen. Methyl or the group

R _{1 is} hydrogen or the - SO ₃ Na group and R _{2 is} hydrogen, the group

NH,

NaO ₃ S

-NH

NH

means, in which A is a linear or branched alkylresl is. Distributed homogeneously in part of the polyamide to form a dye concentrate, this dye concentrate mixed with the bulk of the polyamide and then melted this mass. It was found that these dyes were used in the given Process temperatures surprisingly stable and lightfast are. The following anthraquinone dyes are suitable:

formula

hue

O NH

Η, Ν Ο

blue

CH ₃

The color concentrates are produced in such a way that • ie preferably 5 to 30 percent by weight of dye contain. To produce them, the dye powder can be mixed with a polyamide granulate and homogenize the mixture in a heated extruder, whereby the color concentrate melt is advantageously processed into granules. With especially temperature sensitive dyes can be obtained by using polyamides with reduced molecular weight or by using mixed polyamides, the processing temperature in the extruder is considerable be decreased.

In a special embodiment of the process the dye or the dye mixture or a dye solution in which the dye is in a solvent compatible with polyamide, e.g. B. Ethyl glycol is dissolved, with exclusion of air in a previously prepared polyamide or mixed polyamide melt is stirred in, with the use of a dye solution of the solvent is evaporated again and is homogeneous after the dissolving of the dye Color concentrate melt processed into granules. In the production of polyamide or mixed polyamide green

Melt can matt and / or color pigments can also be used.

The dye concentrate granulate can either be spun as a mixture with normal polyamide granulate or a continuously produced polyamide melt via a melting and metering device be added before spinning. There is general dye content in the molded articles from about 0.01 to 2.0% is required. The fiber concentrate can also be used in a mixture with matting or color pigment concentrates.

Coloring and / or matting pigments can also be added to the starting materials before the polymerization Anti-aging agents, viscosity stabilizers, etc. are added.

By spectrophotometric extinction measurement of the dye concentrate solution in cresol in comparison with the dye solution it can be demonstrated that under the mild processing conditions no detectable at 200 ° C even after 6 hours' dwell time in the mixed polyamide melt Dye degradation has occurred.

example

Preparation of a dye concentrate in an extruder 15 parts by weight of an anthraquinone dye of the formula

O NH ₂ H ₂ NO

SO ₃ Na NaO ₃ S

CH,

! »Earth mixed with 85 parts by weight of polyamide 6 granules (relative viscosity 1 g / 100 ml in cresol = 2.70)

and processed in an extruder at 25C to a homogeneous melt and then to granules. Using a polyamide with a solution viscosity 2.0, the Verarbeitungstemperalur can be reduced to about 220 ⁰ C.

Example 2

Production of a dye concentrate
in the autoclave

In a stirred autoclave made of stainless steel, a mixed polyamide 6/66 85 weight percent / 15 weight percent appropriate proportions by polycondensation of caprolactam and hexanediammonium adipate prepared at 250 ⁰ C under pressure in a known manner. After releasing the pressure, the temperature of the mixed polyamide melt is reduced to about 200 ° C. and an anthraquinone dye according to Example 1 is added with the exclusion of air, so that the color concentrate melt contains 15 percent by weight of dye. After about an hour, the dye has distributed homogeneously in the melt. The processing to granulate can be done according to a dry or wet spinning process.

By increasing the amount of dye added, a dye containing 20 percent by weight can also be added Make concentrate.

Example 3
Manufacture of dyed threads

A mixture of 6.7 parts by weight of 15% color concentrate (prepared according to Example 1 or 2) and 93.3 parts by weight of polyamide 6 granules is dyed deep blue in a spinning apparatus which is heated to 260 to 270 ^{° C. and is equipped with a mixing roller} Threads with a final titer of 90/25 den spun. The light, washing, sweat, chlorine, rubbing. The threads are very fast to dry cleaning, ironing and acid.
If a mixture of 0.67 parts by weight of color concentrate and 99.4 parts by weight of polyamide granules is used, the result is light blue-colored threads with correspondingly good coloristic fastness properties.

Claims (1)

Patent claims: 1. Process for the spin-dyeing of shaped produced by the melt-spinning process Formed from linear, synthetic polyamides with the help of anthraquinone dyes soluble in polyamide, characterized in that anthraquinone dyes of the formula