Crease recovery

Crease recovery angle grey cotton bleached cotton < >... 

High dry crease recovery angle Lower wet crease recovery angle... 

Normally a high dry crease recovery angle is preferred because the appearance of the dry textile is more important than that of the wet one. Between these two extremes is the moist cure, a 5-20 hour room temperature reaction with 6 % above normal moisture regain. The fabric properties of the moist cure are a good compromise between the extremes of the dry and wet processes. The moist cure is preferred when high tear strength of the finished fabric is required, but controlling the critical moisture level can be very difficult. 

These difficulties with moisture control are overcome in a continuous process using a hot flue. There the residual moisture of the fabric is easily regulated by the content of steam in the air at 6-10 %, where the best compromise of the easy-care factor (ECF) and the strength loss factor (SLF) is realised. ECF includes dry and wet crease recovery angles and the Monsanto values. SLF is a combination of... 

Flat fabrics are creased in a specified apparatus either in dry or in wet state. The final dry or wet crease recovery angle is measured. 

Elastomeric finishes are often combined with easy-care and durable press finishes. The silicones reduce abrasion, increase tearing strength (Ehnendorf testing apparatus - ASTM D1424), and crease recovery. For equal crease resistance and durable press performance the amount of cellulose crosslinking agents can be markedly reduced in these combinations. ... 

The KAURIT types improve the crease-recovery and dimensional stability of cellulosic textiles. They reduce the swelling capacity of these textiles and produce permanent calender and plisse effects. 

KAURIT S reacts under mild curing conditions, mainly with formation of crosslinkages with itself, and it imparts good crease-recovery and a firm and resilient handle to the goods. 

FIXAPRET BU produces finishes with good wet crease-recovery, but only moderate dry crease-recovery. The loss in abrasion resistance and tear strength is generally speaking, slight. 

In order to obtain good dry crease-recovery, it is advisable to combine the product with a KAURIT type. FIXAPRET BU has no influence on the light fastness of reactive and direct dyed shades. On the other hand, the finishes are not chlorine resistant. 

PERAPRET HVN is used as additive in resin finishing. It cuts down the loss of tear strength and abrasion resistance and improves the crease-recovery, so that the amount of N-methylol compound in the recipe can be reduced somewhat without Impairing the crease-recovery. The rub fastness of naphtol and Indanthren dyeings is improved. 

The concentration used will depend upon the type of cloth being processed and also the degree of crease recovery the customer might desire. 

Resin finishing softener for cotton and polyester/cotton fabrics. Improves tear strength and crease recovery. 

The wide range of natural and man-made fibres provides many combinations to create new effects with desirable properties. Strength, wearibility and crease recovery are the main properties responsible for synthetic fibres becoming established for blends with cotton, viscose and wool. The acrylics are also in much demand for such blends, while polyamide fibres and triacetates are of secondary importance. 

Mercerization improves dimensional stability of cotton woven fabrics [63]. When knitted fabrics are compared with respect to their relative openness, temperature increases can be said to improve mercerization because when the goods are bleached and then mercerized, the fabric becomes more dense. However, when unbleached fabrics are mercerized, the fabrics become more open [64]. Mercerization also gives moderate improvement in crease recovery of cotton fabrics [65] as well as some protection against the decrease in tensile strength caused by easy-care finishing. 

The determination of crease recovery angle before and after heat-setting of the fabric is done. The extent of crease-recovery of heat-set fabric before and after setting at and above 170-175 C will give idea of the degree of heat-setting. 

More recently it has been found that THPC will react with ammonia to give an insoluble polymer and this has resulted in a simplification of the Proban finish. After padding with THPC the cotton is exposed to ammonia gas followed by immersion in aqueous ammonia. No heat setting is necessary and there is some improvement in wet crease-recovery, suggesting that there is a degree of cross-linking. 

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