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...  

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

A bit Know How About Tetrachloroethylene....Dry Cleaning Agent

Dry Cleaning

Tetrachloroethylene, also known under its systematic name tetrachloroethene and many other names, is a chlorocarbon with the formula Cl2C=CCl2. It is a colourless liquid widely used for dry cleaning of fabrics, hence it is sometimes called "dry-cleaning fluid." It has a sweet odor detectable by most people at a concentration of 1 part per million (1 ppm). It finds its abundance use in textile. Textile Laboratory normally uses two gallons per month for testing purposes. International organization for standardization also advises its use in its standard for textile testing in ISO 105 DO1

Health and safety
The International Agency for Research on Cancer has classified tetrachloroethene as a Group 2A carcinogen, which means that it is probably carcinogenic to humans.Like many chlorinated hydrocarbons, tetrachloroethene is a central nervous system depressant and can enter the body through respiratory or dermal exposure. Tetrachloroethene dissolves fats from the skin, potentially resulting in skin irritation.
Animal studies and a study of 99 twins by Dr. Samuel Goldman and researchers at the Parkinson's Institute in Sunnyvale, California determined there is a "lot of circumstantial evidence" that exposure to Tetrachloroethlene increases the risk of developing Parkinson's disease ninefold. Larger population studies are planned

Testing for exposure
Tetrachloroethene exposure can be evaluated by a breath test, analogous to breath-alcohol measurements. Because it is stored in the body's fat and slowly released into the bloodstream, tetrachloroethene can be detected in the breath for weeks following a heavy exposure. Tetrachloroethylene and trichloroacetic acid (TCA), a breakdown product of tetrachloroethene, can be detected in the blood.

Conclusion

Proper handling and safety equipment (Masks, Gloves etc) should be utilized during performing test containing dry cleaning agent Tetrachloroethylene. 

Chemistry in the Pulp and Paper Industry

21 - 22 December 2009

Sankt-Peterburg, Russia

The event format: lectures, presentations, Round Table, information, know-how and experience exchange.

Target audience: technical directors, chief engineers, chief technologists, chief experts in metrology, experts of central laboratories and technical inspection departments, experts of research laboratories of enterprises, technologists, management and experts of instrumentation and automation services, specialists of chemical laboratories, experts in water treatment, ecologists.

The following issues are suggested to be discussed at the Conference:

1. Main directions in development of chemical processes in the pulp and paper industry.

2. Wet End chemistry – new factors and appropriate estimation methods.

3. Secondary fiber deinking and bleaching with up-to-date chemicals.

4. Modern trends in surface treatment.

5. Some aspects of nanotechnologies in the pulp and paper industry.

6. Higher efficiency of chemical aids (with the use of dosing and control systems in particular).

7. Experience in introduction of new chemicals and technologies at pulp and paper mills.

The Registration Fee: 350 €.

Sustainable chemistry for the leather industry

Specialty chemicals group LANXESS is exhibiting a comprehensive range of products at the India International Leather Fair(IILF)in Chennai, India, on January 31 to February 2, 2010. Jürgen Hackenbroich, head of the Asia Pacific region in the Leather business unit, comments: “LANXESS continues to provide the Indian leather industry with premium products for so called ECO leather. Our technologies conserve resources and minimize both the amount of waste generated and the use of critical substances.” Levotan LB reinforces LANXESS’ role as one of the leading suppliers of softening polymer tanning materials, which are increasingly replacing between 55 to 75 percent of the fatliquor offer because of their technical and ecological advantages. New, versatile Levotan LB permits the cost-effective production of shoe and upholstery leather that are lighter, fluffier and softer than conventional fatliquored leather but nevertheless very durable. Levotan C-IN is a dispersing, lightfast anionic polymer retanning material. In combination with replacement syntans and vegetable and resin tanning materials it gives soft and tight leather. Levotan C-IN has good dispersing action and can be combined with vegetable tanning materials. It is highly suitable for milled leather, e.g. bag leather, shoe nappa and garment leather.Levotan C-IN helps to stabilize acrylic polymers and disperses them well, even at low pH values, thus keeping the grain smooth. Use of this product has been shown to considerably reduce the amount of wrinkling on different raw materials, thereby increasing the cutting yield. New Tanigan VR-IN combines all the advantages of modern chemistry with those of a vegetable tanning material. Because of its extremely well-balanced property profile, Tanigan VR-IN can be used to replace some or even all of the vegetable tanning materials in the retannage, depending upon the raw material quality. Compared with certain vegetable tanning materials, this sulfone-based synthetic organic tanning material has outstanding heat resistance and lightfastness properties and a pale, neutral color giving a brilliant dyeing. It also gives excellent filling and embossing characteristics. At IILF, LANXESS will launch its sulphon based retanning agents Tanigan BN-IN, Tanigan HO-IN, and Tanigan 3LN-IN. All these syntans contain low formaldehyde (HCHO): Tanigan BN-IN is a replacement tanning material for the tannage and retannage of very soft and full leather. Tanigan HO-IN, a versatile, lightfast and very good filling replacement syntan, is very suitable for the retannage of chrome leather and the tannage of chrome-free leather. It can be used as a sole tanning material or in combination. Tanigan 3LN-IN is a lightfast replacement tanning material with excellent resistance to heat yellowing for the tannage of white leather and for the retannage of chrome leather. It can also be used for colored nappa leather because of the good dyeing properties.

Instant Ice..what a chemistry