Carboxymethyl Starch for Reactive Printing

Reactive evaluation information to send

• Candidate K6 K5 K9 grade or grade not yet selected
• Raw material DS and sample or batch reference
• Powder or flake form
• Fabric type and fibre composition including cotton viscose lyocell or blends
• Reactive dye class colour and whether the shade is used alone or in a combination
• Actual print method screen or equipment conditions and pattern coverage
• Complete print paste recipe context including CMS loading alkali system electrolyte or salt level urea or humectant and other auxiliaries with actual amounts where disclosure is possible
• Target paste viscosity and the measured CMS result with its method
• Paste preparation water mixing hydration holding and measurement conditions including paste holding time after alkali addition where relevant
• Fixation route and actual conditions for steam temperature and time or cold pad batch dwell
• Washing sequence including cold wash hot wash soaping neutralization if used and finishing
• Current observations for paste stability after alkali addition colour yield outline definition penetration staining wash off and handle
• Whether the trial uses a single dye or a combination and how shade reproducibility will be assessed
• Acceptance criteria and the procurement decision the trial must support

Independent reactive printing process context

This study compared sodium alginate with carboxymethyl starch samples of different degrees of substitution in reactive colour print pastes on cotton It is background context and does not test KARN grades or prove suitability for a specific production recipe

• Chemistry of Fiber Reactive and Reactive Disperse Dyes in the Printing ProcessCotton Incorporated Technical Bulletin ISP 1015 Copyright 2006Read the Cotton Incorporated PDF

  The bulletin explains reactive dye fixation with alkali and states that starch based thickeners can react with the dyestuff which makes thickener selection critical It presents sodium alginate as a reference thickener that does not react with the dye and is stable to the electrolytes present in the print paste These points define what to verify with a modified starch and are not a CMS test result

• A new insight into the rheological properties of alginates and carboxymethyl starches for printing of reactive coloursBandyopadhyay Mukhopadhyay Afini Salaskar Acharekar Indian Journal of Fibre and Textile Research 1999 volume 24 issue 1 pages 49 to 57Read the NIScPR PDF

  The study compared sodium alginate with CMS samples of different degrees of substitution in reactive colour print pastes on cotton and related rheological behaviour to printing performance It reported that apparent viscosity alone did not predict print quality and that one CMS sample closely matched the alginate reference The CMS samples were not KARN grades and the study does not define a KARN production recipe

What the sources do not establish

The Cotton Incorporated bulletin states that starch based thickeners can react with reactive dyes and that thickener selection is critical It does not test carboxymethyl starch or KARN grades The 1999 study used laboratory prepared CMS samples with degrees of substitution from 0.23 to 0.30 and one reactive print paste recipe on cotton It did not test KARN K5 K6 or K9 and does not establish a production recipe alkali dose electrolyte level fixation schedule or wash off protocol Its finding that apparent viscosity alone did not predict print quality is a reason to evaluate the actual print result rather than transfer a study concentration to KARN CMS