Shrinkage control

Specialty Aluminas. Process control (qv) teclmiques permit production of calcined specialty aluminas ha nng controlled median particle sizes differentiated by about 0.5 ]lm. Tliis broad selection enables closer shrinkage control of high tech ceramic parts. Production of pure 99.99% -AI2O2 powder from alkoxide precursors (see Alkoxides, metal), apparently in spherical form, offers the potential of satisfying the most advanced appUcations for calcined aluminas requiring tolerances of 0.1% shrinkage. 

Like methylolureas, cycHc ureas are based on reactions between urea and formaldehyde however, the amino resin is cycHc rather than linear. Many cychc urea resins have been used in textile-finishing processes, particularly to achieve wrinkle resistance and shrinkage control, but the ones described below are the most commercially important. They ate all in use today to greater or lesser extents, depending on specific end requirements (see also Textiles, finishing). 

The solution (pad bath) contains one or more of the amino resias described above, a catalyst, and other additives such as a softener, a stiffening agent, or a water repeUant. The catalyst may be an ammonium or metal salt, eg, magnesium chloride or ziac nitrate. Synthetic fabrics, such as nylon or polyester, are treated with amino resias to obtaia a stiff finish. Cotton (qv) or rayon fabrics or blends with synthetic fibers are treated with amino resias to obtain shrinkage control and a durable-press finish. 

Textile finishing encompasses a broad range of approaches and may be directed toward needed properties such as shrinkage control or smooth-dry performance or toward developing properties for specific end uses such as flame retardance, soil release, smolder resistance, weather resistance, or control of static charges. 

Melamine-formaldehyde condensates are also useful in textile finishing. For example, they are useful agents for permanent glazing, rot proofing, wool shrinkage control and, in conjunction with phosphorus compounds, flameproofing. 

Melamine resins also are used for the production of decorative laminates. The amino resins are able to modify textiles like cotton and rayon by imparting crease resistance, stiffness, shrinkage control, fire retardance and water repellency. They are also used to improve the wet strength, rub resistance and bursting strength of paper. 

Bucknall, C.B.. Partridge, I.K. and Phillips, M.J. (1991). Mechanics of shrinkage control in polyester resins containing low-profile additives. Polymer 32. 636-640. 

CNC MEL DF 50 is a modified melamine formaldehyde resin which is used on medium to lightweight polyester/cotton blends to Impart both shrinkage control and a crisp resilient hand. 

CNC REZ 550 produces excellent crush resistance and shrinkage control on regular CRF or permanent press work. 

CNC REZ K is a modified ethylene urea formaldehyde resin which was created to give the finisher a thermosetting resin which possesses all of the outstanding features of cyclic resins as to shrinkage control, crease resistance, hand appeal and also not detract from soil release properties. This resin gives fairly soft hand on all classes of fibres and is exceptionally durable on the polyester/cotton blends. 

ARIDRY P can be used as a softener, water repellent, water repellent shrinkage control combination and as an extender for SCOTCHGARD or ZEPEL (fluorochemicals). 

DANSET MUF is a 64% solids urea formaladehyde condensate in clear liquid form, modified for maximum storage stability. The resin will remain completely water soluble for over a year at room temperature. Its minimum degree of polymerization makes it ideal for shrinkage control and wash and wear properties on rayon and rayon blend fabrics and other cellulosics. 

This material is a cyclic methoxylated urea formaldehyde thermosetting resin, designed to supply crease resistance, shrinkage control, in a minimum of stiffness and hand. This material also exhibits excellent stabiltity with prolonged storage, is supplied as a clear colorless thin liquid. Catalysts are required. 

Gives excellent wash/wear properties and shrinkage control for pre- or post-cure application. 

Modified glyoxal reactant that gives excellent shrinkage control. 

Low cost modified carbamate that gives less than 500 ppm of fabric formaldehyde excellent shrinkage control and wash/ wear properties. 

Carbamate reactant designed for excellent shrinkage control and wash/wear properties pre-cure application only. 

For use where a full hand is desired gives shrinkage control on cellulosic fabrics--etherified UF resin. 

Shrinkage control and fabric smoothness, durable to many home or commercial launderings, are very desirable properties for most textile uses. PERMAFRESH 85 provides high performance results while maintaining a low level of formaldehyde liberation on the treated substrate. 

Low formaldehyde levels on sensitized and cured fabrics Chlorine resistant to commercial launderings Excellent dry scorch resistance Excellent shrinkage control Excellent fabric smoothness... 

A thermosetting melamine derivative in water that cross links polymeric materials builds hand of nylon fabric and provides shrinkage control to cellulosic fabrics. 

PERMAFRESH 106 reacts with starches and synthetic polymers such as polyvinyl alcohol and acrylates. Alone, PERMAFRESH 106 provides a firm hand on polyester and nylon fabrics and reacts with cellulosic fabrics to provide shrinkage control. PERMAFRESH 106 also aids in obtaining and maintaining satisfactory results when used with water and/or oil repellent products. 

Shrinkage control, fabric smoothness, and crease retention durable to many home or commercial launderings are very desirable properties for postcure apparel fabrics. PERMAFRESH 113-B provides these properties while also providing shade change protection and whiteness retention. PERMAFRESH 113-B is also suitable for most precure applications where shade change of sensitive dyestuffs is a major problem. 

Shrinkage control and fabric smoothness with little, if any, effect on shade are very desirable properties for textile uses where very sensitive dyestuffs are needed to produce the desired shade. PERMAFRESH 125 can provide this with many direct and reactive dyestuffs. PERMAFRESH 125 is self-catalyzed with a specially selected system. Although designed primarily for knit fabrics it can be used on cellulose containing woven fabrics. 

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