Laundering detergent

The tetramethylol derivative of DABT, prepared by reaction of DABT with alkaline aqueous formaldehyde, polymerized readily on cotton. It imparted excellent flame retardancy, very durable to laundering with carbonate- or phosphate-based detergents as well as to hypochlorite bleach. This was accomphshed at low add-on without use of phosphoms compounds or antimony(III) oxide (75—77). 

Detergent Applications. The primary function of FWAs in the laundry process is to whiten fabric load and maintain the original appearance of the white, laundered articles. Laundering is characterized by repeated appHcation to the same item. Fluorescent whiteners used in this repetitive process have to compensate for the reduction in whiteness and contribute toward prolongation of the usefiil life of the textile material. 

CeUulases have appeared in a few laundry detergents around the world. Since there are few, if any, ceUulase-based soils present on home laundry, any laundering benefit from ceUulase would be expected to come from action on cotton fabric. The nature and magnitude of such benefits is uncertain (see Enzya s, Ejdusthial Applications). 

As with the case of energy input, detergency generally reaches a plateau after a certain wash time as would be expected from a kinetic analysis. In a practical system, each of its numerous components has a different rate constant, hence its rate behavior generally does not exhibit any simple pattern. Many attempts have been made to fit soil removal (50) rates in practical systems to the usual rate equations of physical chemistry. The rate of soil removal in the Launder-Ometer could be reasonably well described by the equation of a first-order chemical reaction, ie, the rate was proportional to the amount of removable soil remaining on the fabric (51,52). In a study of soil removal rates from artificially soiled fabrics in the Terg-O-Tometer, the percent soil removal increased linearly with the log of cumulative wash time. 

The different detergents are an attempt to copy the typical detergent composition commercially available in the U.S. and European markets. The more severe tests in the C06 series are designed to approximate the effect expected from five repeated launderings. In view of the variety of conditions associated with this test it is vital to ensure good communication and data recording in operating the test. 

Laundering Conditions Around the World. Any laundeting process is an iaterplay between the equipment used the materials entering the process, ie, detergent, additional bleach, fabric softener, or water and the procedure followed. Equipment and procedures ia three principal geographical areas are summarised ia Table 3. 

The I I cleaning procedures as a whole, compared with household laundering, are characterized by huge variations in the composition of the soils, types of surface to which they adhere, cleaning time available, etc. The optimum choice of enzyme type and dosage level normally has to be established through a cooperation between the customer (end user), manufacturer of the detergent, and enzyme producer. 

Almost all man-made fibres destined for sale as white goods are producer-brightened by the manufacturer and white textiles are almost always laundered using detergents containing cellulose-substantive FBAs [20]. To evaluate an FBA it is necessary both to apply the product to the desired substrate and to measure the whiteness of the treated material. Measurement of the fluorescence intensity of the FBA-treated substrate provides useful additional, although different, information. 

The laundering process will become more energy-efficient and use less water and adequate low amount of detergent. It will be more or less automatically adapted to the types of textiles, the washing program, dirt content, wash load, to temperature levels accepted and the detergents used, using sophisticated electronic control systems. 

As recommended laundering temperatures have tended to fall in recent years, a bleach consisting of sodium perborate activated by addition of tetra-acetylethylenediamine (4.110 TAED) has become an important component of household detergent formulations. This system is effective at temperatures as low as 40-50 °C. A recent study of the effects of TAED-activated peroxy bleaching on the colour fastness of azoic dyeings has demonstrated that the sensitivity of these products can be related to their chemical structure. Electron-donating substituents in the diazo component enhance resistance to oxidative attack under these conditions, as do the size and complexity of substituents present in the coupling component [110]. 

Color-fastness of objects to be cleaned, especially for laundry detergents Improved properties of objects to be cleaned, e.g. UV protection for laundered garment... 

Detergents. Ultramarine pigments are widely used to enhance the effects of optical brightening agents in improving whiteness of laundered fabrics [3.176], They do not stain or build up with repeated use. 

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