Hand building finishes durable

Hand building finishes that lose their effect after one or two launderings are considered non-durable. The two major product types of non-durable hand builders are starch derivatives and polyvinyl alcohol. Natural starch is produced commercially from potatoes, com, wheat, rice and tapioca. Its two main components are polymers of a-glucose, amylopectin and amylose, shown in Fig. 4.1. The thickening effect of starch is mainly due to the long and branched amylopectin chains. 

Hand building finishes that retain their stiffening and fullness effects after repeated launderings are considered to be durable. These products are usually aqueous emulsions of polymers that form water-insoluble films on the fibre surface when dried. The three main types of products are vinyl acetate-containing polymers, acrylic copolymers and thermosetting polymers. 

Usable for anti-pilling Hand building finishes, for cellulosics easy-care Durable press finishes Cellulase finishes... 

The following sections will discuss some of the more important test methods in use for fabrics with durable press, flame-retardant, soil release, repellent, UV protective, antimicrobial, anti-insect, anti-felting, hand building and weighting finishes. 

The addition of 0.02% of an aqueous emulsion of silicone liquid into sand fibre slate reduces its water absorption by two and noticeably increases its cold resistance. Silicone liquids can be also put on finished constructions in the form of a 5% aqueous solution, which penetrates to the depth of 3-6 mm and after drying forms a durable waterproof surface for 5-10 years. This treatment can be used on various works of art, famous architectural buildings, etc. Plastered facades can also be waterproofed with good results. Treated plaster does not absorb rain drops on the other hand, common plaster completely absorbs all rain drops after 30 seconds. 

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