Cotton fabrics preparation process

CP esters are generally prepared as the ammonium salt [9038-38-4] by the reaction of cellulose with phosphoric acid and urea at elevated temperatures (130—150°C). The effects of temperature and urea/H PO /cellulose composition on product analysis have been investigated (33). One of the first commercially feasible dameproofing procedures for cotton fabric, the Ban-Flame process (34,35), was based on this chemistry. It consists of mixing cellulose with a mixture of 50% urea, 18% H PO, and 32% water. It is then pressed to remove excess solution, heated to 150—175°C for 5—30 minutes, and thoroughly washed (36). 

The chemical name of this reagent is l,3-bis(hydroxymethyl)-4,5-dihydroxy-imidazolidinone-2 but it is usually called DMDHEU or the glyoxal reactant because it is prepared from glyoxal, urea, and formaldehyde. Other methylolamide agents that have been used for producing wrinkle resistance in cotton include the aforementioned urea formaldehyde, dimethylolurea, dimethylolethyleneurea, and formaldehyde adducts of melamines (triazines), acetylenediurea, propyleneurea, uron, triazones, and alkyl carbamates. Reactions between methylolamides and cellulose occur in the presence of acid (or Lewis acid) catalysts and are very fast at elevated temperatures—sufficiently so that they are adaptable to the requirements of rapid, commercial processing of cotton fabrics. 

Cotton fabrics (15g) were modified using isothermic exhaustion process (75 C). The bath was prepared with 15% (owf) of cationic antibacterial product (monocationic salt) and epichlorohydrin (molar ratio 1 1) and 20 gL of sodium hydroxide. The liquor ratio was 1 20. 

Microcapsules with cationic character, prepared by the company Lipotec, have been used for application on cotton fabrics (Style 400, Test Fabrics, Inc). In a preliminary study, a sun filter (OMC) was used as a reference probe during the encapsulation process. 

The SMPU solution prepared was used directly in solution form, and was prepared by mixing 80 g of SMPU solution with IL of water. The process employed was the traditional pad-dty-cure process, whereby the cotton fabric is immersed into the finishing solution on a padding machine (Rapid 354) arrd padded twice between two mbber rollers at a pressme of 3 MPa. After the padding process, the wet pick-up of the fabric was about 75% (based on a completely dry sample). It was subsequently dried at 80°C for two minutes, before being cured at 120°C for three mirmtes. 

The greatest industrial consumption of monobasic aluminum acetate has been as a solution in the preparation of red color lakes for the dyeing of cotton. Formation of a water-resistant coating on fabrics, paper, leather, or other materials is also an important appHcation. In this process, for example, cloth is dipped into a solution of water-soluble soap, then into the aluminum salt solution, forming an insoluble, water-resistant aluminum soap coating on the fiber surfaces (10). 

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