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Dec 30, 2010

Pre Wash with Acetic acid can control back staining specially in the case of Turquoise Color.

SUBJ-14:
Pre Wash with Acetic acid can control back staining specially in the case of Turquoise Color.

Chemicals:
Acetic Acid (Conc), Sodium Alginate, Soap (Polyglycolether, Nonionic).

Process:
Purpose is to control back staining during washing in reactive printing. Some red and all turquoise bleed a lot during washing. Washing fastness like ISO 105 CO3 and 105 CO6/C2S also shows that turquoise are have very poor fastness, Any way in this post we are only concerning about the reacting after washing off of freshly printed fabric. We are not concerned with any kind of fastness like washing, Perspiration and Dipping etc.


Recipe:
Stock paste:
Mild. Oxidizing agent                10  g/Kg
Urea                                        100g/Kg
Sodium Bicarbonate                 25g/Kg
Alginate Thickener                   25g/Kg
Water                                      Balance
Total                                       1 Kg


Dye Glass:
Dye                                         50g/Kg
Stock paste                              Balance
Total                                       1 Kg


Process:
Print and dry at 110-120°C for 1Min.
Cure at 200C for 1 Min

Prewash
With and Without Acetic Acid
            With..................Without...............



    Dec 28, 2010

    Pakistan asks India to keep up promise of cotton export

    With Pakistan reeling from the after-effects of floods, its textile mill sector has appealed to India to honour the commitments for dispatching raw cotton, in letter and in spirit.
    After floods devastated large tracts of farm land, cotton production in Pakistan was affected along with other major crops. In such a situation, Pakistani textile mills not only require the contracted amount of cotton from India, but a liberal gesture in the form of additional raw cotton as well.
    Addressing a press conference here, All-Pakistan Textile Mills Association vice chairman Shahzad Ali Khan pointed out that India exported only one lakh bales out of the contracted quantity of 10 lakh bales. What the industry needed was not just the entire contracted amount, but an additional quantity. India had so far exported about 30 lakh bales of cotton to other countries and was in a position to assist the Pakistani textile industry.
    Urging India to “help a neighbour,” Mr. Khan expressed the hope that the remaining quantity of nine lakh bales would be shipped at the earliest. Pakistan faces a severe supply crunch on the raw cotton front due to floods in parts of cotton growing areas in the country. Pakistan lost about 25 lakh bales of cotton and faces an overall deficit of 40 lakh bales.
    The Pakistan Textile Mills Association, he said, had already submitted a request in this regard to the Indian High Commission in Islamabad. A similar plea has been lodged with the Pakistan High Commission with the hope that it would be followed up with the Indian industry and the government. Desperate for succour from India, the Pakistani textile industry has also taken up the issue with the cotton exporters in Mumbai.

    Source:
    INDIAN NEWSPAPER THE HINDU

    Dec 27, 2010

    Discharge Printing on direct dyed fabric with Potassium permanganate(KMnO4).

    SUBJ-13:
    Discharge Printing on direct dyed fabric with Potassium permanganate(KMnO4).

    Chemicals:
    Potassium permanganate (Oxidizing agent), Sodium bisulfite (Reducing agent), Acetic Acid (Conc), Special Thickener (inorganic compound based on silicate), Soap (Polyglycolether, Nonionic).

    Process:
    Purpose is to discharge all direct dyed substrate through Oxidation reaction of Potassium permanganate in acidic pH and than Reduction through Sodium Bisulfite again in acid pH. than finally soaping.

    Recipe:
    Stock paste:
    Special Thickerner                35g/Kg
    Potassium permanganate         40g/Kg
    Acetic Acid                             10g/Kg
    Water                                      Balance
    Total                                       1 Kg


    Processing Steps Involved:
    ¯  Print and Dry at 100-120C.
    ¯  Washing off in a reduction for fifteen minutes at 70C, bath containing
    1.      Sodium Bisulfite         10g/L
    2.      Acetic Acid                 0.5g/L

    Wash for 10Min at 70C with Soap (Polyglycolether, Nonionic).
    ¯  Rinse Warm and Cold.


    Remarks by:
    Direct dyes have been used for quite long time for dyeing cellulosic fabric. These dyed fabric can be easily discharged through Sodium formaldehyde sulfoxylate (commonly called Rangolit C) or this can also be done through Potassium permanganate, Results are quite fine. Whole process is in front of you.




    Authentic Pigment Mens Direct - Dyed Ringspun Short Sleeve T-Shirt - BRICK - XXX - LargeDyeing Properties, Direct DyestuffsHand Dyeing Yarn and Fleece: Custom-Color Your Favorite Fibers with Dip-Dyeing, Hand-Painting, Tie-Dyeing, and Other Creative TechniquesDischarge - Fight Back T-Shirt - Medium



    Dec 24, 2010

    Testing and recommending commercial chemicals for controlling back staining in reactive printing washing and wash down effects of Denim ( Enzyme Wash, Stone Wash, Moon Wash)..

    SUBJ-12:
    Testing and recommending commercial chemicals for controlling back staining in reactive printing washing and wash down effects of Denim ( Enzyme Wash, Stone Wash, Moon Wash)..

    Chemicals:
    Dye( Tuquoise was taken for experiment as it is famous for a lot of back staining), Stock paste (Containing Urea, Bicarbonate, Mild oxidizing agent ), Hydrogen per oxide 35%, Soda ash, Routing soap for reactive washing(generally acrylic acids).

    Purpose:
    Back staining is quite a famous issue among printers as it stains white area and minimizes contrast effect and eventually compromising the added value. This is not only the issure for reactive printers but also for Denim industry, Who are busy in dyeing warp yarn of denim and leaving white weft and weaving style ending up with eye catching effect of jean. Now days, Different washes are very famous for carrying out different effects like Stone Wash, Enzyme wash and Moon Wash. When these washes are done dye is released from the warp yarn into liquor (containing some enzyme, acetic acid for maintaining appropriate Ph) these dyes bounce back towards fabric and stick to weft yarn so, again less contrast between warp and weft. New tint of  blue from weft also fade down the actual Denim concept.  So, what can be added to over washing recipe to control this issue.

    With out H2O2...   With H2O2...  


    Dec 20, 2010

    Sulfuric Acid ...King of Chemicals

    Laboratory hazards
    The corrosive properties of sulfuric acid are accentuated by its highly exothermic reaction with water. Burns from sulfuric acid are potentially more serious than those of comparable strong acids (e.g. hydrochloric acid), as there is additional tissue damage due to dehydration and particularly secondary thermal damage due to the heat liberated by the reaction with water.
    The danger is greater with more concentrated preparations of sulfuric acid, but even the normal laboratory "dilute" grade (approximately 1 M, 10%) will char paper by dehydration if left in contact for a sufficient time. Therefore, solutions equal to or stronger than 1.5 M are labeled "CORROSIVE", while solutions greater than 0.5 M but less than 1.5 M are labeled "IRRITANT". Fuming sulfuric acid (oleum) is not recommended for use in schools as it is quite hazardous.
    The standard first aid treatment for acid spills on the skin is, as for other corrosive agents, irrigation with large quantities of water. Washing is continued for at least ten to fifteen minutes to cool the tissue surrounding the acid burn and to prevent secondary damage. Contaminated clothing is removed immediately and the underlying skin washed thoroughly.
    Preparation of the diluted acid can also be dangerous due to the heat released in the dilution process. The concentrated acid is always added to water and not the other way round, to take advantage of the relatively high heat capacity of water. Addition of water to concentrated sulfuric acid leads to the dispersal of a sulfuric acid aerosol or worse, an explosion. Preparation of solutions greater than 6 M (35%) in concentration is most dangerous, as the heat produced may be sufficient to boil the diluted acid: efficient mechanical stirring and external cooling (such as an ice bath) are essential.
    On a laboratory scale, sulfuric acid can be diluted by pouring concentrated acid onto crushed ice made from de-ionized water. The ice melts in an endothermic process while dissolving the acid. The amount of heat needed to melt the ice in this process is greater than the amount of heat evolved by dissolving the acid so the solution remains cold. After all the ice has melted, further dilution can take place using water.

    Source:
    Wikipedia.org

    Dec 17, 2010

    The Textile Industry in Canada: Focus on Technical and Other Value Added Textiles

    e Canadian textile industry has lost much of its competitiveness since the global elimination of quotas at the end of 2004, particularly in mass markets. Between 2005 and 2009 total factory sales by textile mills and textile product mills fell by 44% while sales by the clothing manufacturing industry dropped by 50%.

    The textile industry has faced a number of challenges, including: competition from developing countries; offshore manufacturing by its traditional main customer, the clothing industry; availability, retention and training of the workforce; the strength of the Canadian dollar; trade regulation; capital availability; and access to specialised markets.

    By 2006 it was apparent that the industry needed to diversify into specialised materials such as technical usage textiles (TUTs) and other value added textiles (OVATs). By targeting TUTs and OVATs the industry would be better able to meet, and stimulate, customer demand for products which met special requirements and offered heightened performance.

    To ensure widespread adoption of this strategy, it was proposed that the strengths of the entire value chain be focused on TUTs or OVATs. This was to be achieved through: the utilisation of scientific and technical resources; the implementation of dynamic research and development cooperation platforms; innovation; commercialisation; and business networking.

    The aim of this initiative is to help the industry to compete in the international market place and develop a critical mass. Consequently, its image will improve in the eyes of the public, the business community and the financial community, and the industry will be taken more seriously when major public and private clients are structuring their projects.

    The initiative has already achieved some success. Between March 2007 and June 2009 the number of companies involved in technical and other value-added textiles rose from 241 to about 400, and in mid-2010 it was estimated that this figure had been more or less maintained.


    Source:
    http://www.just-style.com/market-research/the-textile-industry-in-canada-focus-on-technical-and-other-value-added-textiles_id98227.aspx?lk=ud79

    Dec 16, 2010

    Burn out printing on Blend PC (Polyester/Cotton ).

    SUBJ-11:
    Burn out printing on Blend PC (Polyester/Cotton ).



     Chemicals:
    Synthetic Thickener, Sodium Bisulfate, Penetrating Agent, Glycerin and Water.

    Purpose:
    Burnout is a beautiful effect, Which is carried out on blend fabric and specially for those blends which have high percentage of cotton and are reserved dyed (mean polyester portion is either dyed or printed), when cotton burns down dyed polyester gives full shade and vacant spaces. One can literally see across this type of effect.
    One can take simple white fabric, blend of course. Dye or print it with disperse dye in acidic medium than apply burn out recipe afterwards go for reduction cleaning which is required for polyester. This cleaning will also wash down burned cotton.
    Cotton can be chemically burnt out at 200C in presence of Sodium bisulfate (other chemicals were also tested in order to substitute sodium bi sulfate , which is discussed in later portion)

    As a big house Masood textile on its website expresses.

    Preview this picture on large scale

    Denim Discharge or Jeam Discharge

    SUBJ-10:
    Indigo Discharge, Vat Discharge, Denim Discharge or Jeam Discharge all in one.

    Chemicals:
    Potassium permanganate (Oxidizing agent), Sodium bisulfite (Reducing agent), Acetic Acid (Conc), Special Thickener, Soap (Polyglycolether, Nonionic).

    Process:
    Purpose is to discharge Blue or Black color Denim through Oxidation reaction of Potassium permanganate in acidic pH and than Reduction through Sodium Bisulfite again in acid pH. Finally soaping.

    Recipe:
    Stock paste:
    Special Thickerner                35g/Kg
    Potassium permanganate         40g/Kg
    Acetic Acid                             10g/Kg
    Water                                      Balance
    Total                                       1 Kg



    Processing Steps Involved:
    ¯  Print and Dry at 100-120C.
    ¯  Washing off in a reduction for fifteen minutes at 70C, bath containing
    1.      Sodium Bisulfite         10g/L
    2.      Acetic Acid                 0.5g/L

    Wash for 10Min at 70C with Soap (Polyglycolether, Nonionic).
    ¯  Rinse Warm and Cold.



    Remarks:
    This will clearly give you good discharge result. I will try to upload photo effects of these discharges. I also tried some other temperatures for drying which was 150 and 180C but, results were not  too good (mean no big change). One can try other oxidizing agent and reducing agent like sodium pryrosulfite (Sodium meta bisulfite), Sodium Hydro sulfite.

    Please Note  Thickeners (Including both natural, Synthetic) are not compatible with potassium per manganate and acetic acid. They form jelly and heat is evolved during stirring. So, special thickeners are need for this kind of process. That’s why I used word “Special Thickener”. Still need to look for the chemistry of this special Thickener. If  you are familiar with the chemistry of Special thickener. Comments are welcomed.

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