DESCRIPTION
The cold padding batch dyeing process is known for a lot of advantages, including fine color
reproducibility, highly efficient use of a dye, saving of dyeing auxiliaries, energy saving, low
water consumption, and low equipment costs. Special care must, however, be taken for the
preparation of the fabric to be dyed in order to accomplish uniform padding. The cold padding
batch dyeing process is conducted at a padding temperature of about 30" C., and further involves
maintenance of temperature as low as 30" C. to 35" C. for the ageing purpose. It does not
include any dyeing step requiring a heat treatment; therefore, the success of dyeing depends on
the uniformity of padding. The mere application of the process ensures uniform penetration of a
dye solution into the fabric to be dyed and maintenance of a homogeneous fabric structure.
The dyeing process of the invention provides advantageous dyeing of cotton not only in terms of
energy saving but time saving also .Thus it is a energy and time saving industrial process. It
makes protection to human ecologically and economically both as use of hazardous metal salt
like copper and chromium are completely avoided.
Dye effluent is safe as the dye exhaust rat is high and the remaining material in the dye bath is
consisting of ecofriendly auxiliaries.
SUMMARY OF THE INVENTION
It is, therefore, an object of this invention to provide a cold dyeing process for cellulosic fabrics,
which enables dyeing of the fabric in padding efficiently and uniformly without developing any
edge mark or unevenness between the opposite sides of the fabric and without involving any
extensive and complicated apparatus a jigger machine is suitable for this method.
This invention is based on the discovery that the length of time fiom entry of the fabric into the
padding tank to squeezing thereof has an important bearing on the total time needed for dyeing,
which is conventionally 7-8 hours in a continuous jigger machine. If this time can be reduced to
2 hours certainly the production of dyed fabric can go up.
The cellulosic fabrics which can be dyed in accordance with this invention include fabrics of
cotton yarn, fabric or even garments.
Suitable natural dyes which can be employed in the process of this invention include madder,
punica, lac, terminalia or any other natural dye. An appropriate amount of one or more alkalis is
used to suit the dye used. The dye and the alkali should preferably be selected to ensure fixation
of a substantial portion of the dye by ageing over a period of one hour in order to prevent uneven
coloring by dripping of the dye solution during ageing, and avoid any adverse effect of water
droplets which sometimes leave unwanted marks.

I/We claim:
1. A cold padding dyeing process for cotton in form of yam ,fabric or garments with natural
dyes without involvement of heat at any step covered in entire dyeing process
2. The process relates to a process for dyeing of cotton textile material with the natural dyes
by the exhaust method.
3. The process of claim 1, wherein said treatment of Vegeplus and Vegeset ( special
ecofriendly auxiliaries) are used for pretreatment of the fabric for 30 rnins
4. The process of claim 2, wherein said total time for dyeing is 1 hour using natural dyesmaddar/
punica/lac/teminaliac hebula.
5. The process of claim 3, wherein said pH of the dyebath is maintained 8.5 using soda ash
along with VegeDisperse for better dispersion of the natural dye.
6. The process of claim 4, wherein ageing is conducted at a constant temperature between
30" C. and 35" C.
7. The process of claim 4, wherein said solution contains at least one alkali selected from the group consisting of sodium carbonatelsoda ash for maintenance of the pH.
8. The process claims 1, wherein the conventional natural dyeing process requires
temperature of 70 OC -lOO°C .The essential feature of the process of invention is that the
dyeing is done at room temperature without use of heat at any stage of dyeing.
9. The process claims 1, wherein it is a heat conserving process which is a very significant
industrial processing.
10. The process claims 1, wherein the conventional natural dyeing process is completed in
minimum 6 hours. In some cases it bakes two to thrcc days for getting proper shades
. This invention has made the entire dyeing process of 2 hours only. It is a time
conserving process. Approximately 71.4 % time is saved.
11. The process claims 1, wherein significant energy, time and cost reduction as compared to
other conventional dyeing processes has been achieved.
12. The process claims 5, wherein total elimination of the need for salt and other metallic
chemicals such as Copper ,chromium and other metals that are necessary in conventional
dyeing of natural dyes ,our process replaces them with ecofriendly auxiliaries.
13. The process claims 1, wherein excellent wet fastness properties in dyed fabrics.
14. The process claims 1, wherein uniform dye quality is achieved with even color
absorbency and color fastness.