AVCO-TAN APA

THICKENER FOR ACID DYES PRINTING
AVCOTAN APA is a synthetic thickener developed for the convenience production,
handling and use of disperse and acid printing pastes. The product has all the advantages of synthetic thickeners whith lower sensitivity towards elctrolytes.

SPECIFICATION:

Appearance White powder.
Chemical nature Synthetic copolymer modified with a substitued natural polymer and solubilizers.
Compatibility
  1. Can be used together with all chemicals and dyestuffs normally encountered in printing acid dyes.
  2. Is not compatible with strong alkalis, acids, metallic ions, cationics and concentrated electrolytes.
  3. Can be used with hard water together with a suitable complexing agent.
Ionicity Anionic
pH (1% dispersion) 6.5 – 7.0
Solubility Dispersible in water, in concentration up to 2-4%, forms viscous pastes.
Storage stability
  1. Stable for at least 12 months when stored in a dry place in closed container.
  2. Do not store in direct sun.

PROPERTIES & USES:

  1. Outstanding coverage and levelness, sharp definition of prints. Excellent
    results on fine and delicate fabrics.
  2. Increased color yield with good reproducibility.
  3. Produces smooth paste during short mixing time.
  4. Printing paste viscosity is stable for long storage time.
  5. Good washing-off properties.
  6. Does not react with disperse and acid dyestuffs.
  7. Produces thixotropic printing paste which enables to control flow properties of the paste.
  8. Does not bleed out of rotary screens during machine stops.
  9. Does not clog printing screens.
  10. Very easy to adjust viscosity, no need for prolonged swelling time.

APPLICATION:

  1. When preparing the stock printing paste, all the chemicals should be added to the water and allowed to dissolve prior to adding the AVCOTAN APA. The thickener should be added while mixing, It will easily disperse and fully hydrate in some minutes.
  2. Stock paste formulation for Acid dyes
    Water 905 – 880
    Urea 50
    Ammonium sulphate 10 – 20
    AVCOTAN APA 25 – 50
    1000
  3. Printing paste preparation:
    Pre-diluted dyestuffs should be added to the stock paste while stirring.
    If needed, in very high dye concentration, viscosity adjustment is done easily by adding thickener during high speed mixing.
  4. Fixation
    Fixation should be done in the normal procedure required by the type of fixation machine and dyestuffs used. Normal recommendation is steaming in atmospheric steam at 100-105°C for 25 minutes.
  5. Washing off
    Washing off should be done with soft water, or with tap water with the addition of complexing agents. Temperature, type of washing aids and procedures depends on machinery and type of dyestuffs. (For more details refer to the technical bulletin of AVCOL PAM).
  6. To improve definition of the print borders with problematic designes, addition of AVCOPRINT JN (special antimigrant) is very beneficial. Use of 6-10 g/kg will result in sharp and clear borders of the printed area.
  7. In resist printing processes use of AVCOGEN KRK 10-15 g/kg will improve print results.
  8. To improve penetration add 3-6 g/kg AVCOTEX MP.