AVCO-FIX NYJ

FIXING AGENT FOR DYEING POLYAMIDE FIBRES
AVCOFIX NYJ is an after-treatment agent to improve wash-fastness of polyamide fibres dyed with acid dyestuffs. It is also used as a resist agent in dyeing polyamide blends.

SPECIFICATION:

Appearance Brown clear liquid
Chemical nature Aqueous solution of synthetic resin
Compatibility
  1. Compatible with nonionic and anionic products
  2. Incompatible with cationic dyestuffs and auxiliaries.
  3. Incompatible with acids, and alkalies.
Ionicity Anionic
pH (1% sol.) 8 ± 1
Solubility Miscible with water at any ratio
Storage Freezes below O0C. Fully useable after thawing. Shelf life is at least 12 months.

PROPERTIES & USES:

  1. Very effective for improving wet fastness properties of acid dyes on polyamide.
  2. Minimum effect on shade and high fastness of dyed fibres.
  3. Resist agent for dyeing polyamide/wool blends, particularly effective when 1:2
    pre-metallized dyes are being applied.
  4. Resist agent for dyeing wool/cellulosic and polyamide/cellulosic blends with
    direct dyestuffs.
  5. Excellent fixing agent for polyamide fabrics printed with acid dyes, to prevent
    staining of white grounds.
  6. No effect on treated fabrics handle.
  7. Suitable for application in high speed jet machines.

APPLICATION:

AFTER TREATMENT OF POLYAMIDE

The concentration of AVCOFIX NYJ necessary to achieve the maximum improvement in fastness is influenced by the depth of shade being after-treated, the particular dye being used, and the substrate.
Use: 2-5% AVCOFIX NYJ.

After treatment may be carried out either in the cooled dye-bath or in a fresh bath under acidic conditions to effect maximum exhaustion on to the fibre. Ideally, the bath should be adjusted to pH 3-4 with acetic acid or formic acid, followed by the pre-diluted fixing agent.
Treatment should be carried out at a temperature which will ensure optimum results for the quality and type of polyamide being treated. Usually the temperature is about 800C. Treat for 20 minutes.
Following are typical recipes:
  1. After-treatment of predyed polyamide in a separate bath.
    AVCOFIX NYJ 2 – 5%
    Formic acid (85%) 1 – 2g/l
    Adjust to pH 4
    Treat at 80°C for 20 min.
    Drop bath and rinse at 50°C.
  2. One bath, two steps dyeing and after-treatment.
    Dye according to the following recipe:
    AVCOLON NAL 1 – 3g/l
    Acid dyestuffs X%
    AVCOCID HTA 200 1 – 3g/l
    Heat up: 30°C ™ 98°C (1 c/min)
    Run at 98°C for 60 min.
    Cool down to 80°C.
    Add 3-5% AVCOFIX NYJ (slow dosing, over 15 min)
    Run at 80°C for 20 min.
    Drop bath.
    Rinse well at 50°C
RESIST AGENT FOR DYEING WOOL/CELLULOSE AND
POLYAMIDE/CELLULOSE BLENDS
Quantities required are largely dependent on the dye being used and the particular blend dyed. Use of 3-5% should be adequate for most purposes.
To avoid staining of the PA fibres by direct dyes use the following recipe:
AVCOLON NAL 1 – 3 g/l
AVCOFIX NYJ 3 – 5%
AVCOCID HTA 200 2 – 3 g/l
Direct dyes X%
Acid dyes Y%
Dye at 98°C for 60 min, cool down to 80°C, run 15 min.
Drop bath

RESIST AGENT FOR DYEING WOOL/POLYAMIDE

The quantities of AVCOFIX NYJ required depend primarily on the dyes used and on the type of polyamide fibre. Nylon 6, for example requires higher quantities of blocking agent than does nylon 6.6. The exact amount required is best determined by preliminary trials. It has been found that 2-4% of AVCOFIX NYJ are adequate for most purposes.
SPECIAL IMPROVMENT OF WET FASTNESS OF MICRO FIBERS
Since microfibers need more dyestuffs to reach depth, improving of fastness is essential.
Treat with 3-5% AVCOFIX NYJ at pH 4, 80°C for 30 min.
Rinse well at 50°C (4 times)
Treat with 2-4% AVCOFIX ECO at pH 5, 40°C for 15 min.
AVCOFIX ECO treatment can also be done on the stenter frame before final drying/fixing.
STRIPPING OFF AVCOFIX NYJ
To correct dyeing, the AVCOFIX NYJ should be stripped off the fibres.
Typical recipe:
Ammonia( 25%) 3 – 5cc/l
AVCO DISPERSANT NS 3 g/l
Treat at 98°C for 30 min.
1 cc/l caustic (50%) can also be used instead of ammonia, but there is a distinctly influence on shade.
REMARKS
  1. Care should be taken to avoid any residues of nonionic / cationic levelers such as fatty amine polyglycols on the fibres. Fabrics should be rinsed well before the treatment with AVCOFIX NYJ.
  2. Do not mix the product with concentrated acids.