Ozone process for denim

Abstract

An apparatus and a method for decolorizing a denim fabric with an oxidizing gas is disclosed. The process is initiated by producing compressed air which is processed to generate dry air. The air pressure of dry air is reduced to maintain at 10 psig and thereby generates ozone gas. A negative pressure is maintained to ensure no ozone leak out to ambient from a washer. The denim fabric may be exposed to a controlled amount of ozone gas for a predetermined time such as a process time. Whenever the process time expires, the amount of ozone gas is converted back to oxygen by running a variable speed motor at high speed to create a negative pressure within the processing unit and released to atmosphere. The method also incorporates a means for monitoring the level of ozone concentration in ambient for the safety of operators.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]Not Applicable.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT[0002]Not Applicable.FIELD OF THE INVENTION[0003]This invention relates to an apparatus for the treatment of a denim fabric with an is oxidizing gas. More particularly, an apparatus for treating the dry denim fabric with ozone gas for decolorizing dyes, coloring agents on the fabric.DISCUSSION OF RELATED ART[0004]Denim is considered to be world's one of the oldest fabric. The popularity of denim fabrics is high in almost every age group. Denim fabrics provide comfort, durability, versatility and glamour. The decolorization of denim fabrics are done by processes such as stone washing, ice washing, sand blasting, rubbing with sand paper or pumice stone etc. Neutralization process using hot water and chemicals, and processes utilizing potassium permanganate spray are also used to provide the desired fading effect.[0005]U.S. Pat. No. 7,252,688 to Tashiro on Aug. 7,...

AI Technical Summary

Benefits of technology

[0013]Controlled amount of ozone passes through the at least one inlet ozone solenoid valves The washer may be represented as washer A or washer B, as in this instance. The washer, is preferably washer A or washer B is where the dry denim jean is exposed to ozone gas and the oxidation on the fabric occurs. The desired effect on the at least one dry denim fabric can be controlled by duration of oxidation, concentration of ozone, and combination of both. The duration of oxidation may be known as process time. The process time is set on the at least one master control unit. At the process time, the at least one variable speed motor is run at low speed to create the negative pressure in the at least one washer. The negative pressure prevents ozone leak out to ambient from the at least one washer.

[0015]The present invention is an improved apparatus for decolorizing a denim fabric with an oxidizing gas having an ozone monitoring unit for monitoring the concentration of ozone in ambient for providing safety of operation. Such an apparatus is free from costly enzymes and chemicals that have high cost and unfriendly to the environment. Moreover, such an apparatus eliminates the usage of hot steam thereby saving energy. Other is features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

Problems solved by technology

However, in this process costly enzymes are utilized for decolorizing the fabrics.

Moreover, this process also requires chemicals that have high cost and unfriendly to the environment.

However, this device utilizes hot steam for treating the garments thereby wasting a considerable amount of energy.

Images