Repellent finishes silicone water repellents

CNC CATALYST ZA should be added to the finishing bath after the silicone water repellent has been dissolved in the bath. 

This material is a metallic zinc/organic acid emulsion catalyst designed for use with silicone water repellent and has been found to be most efficient and effective in producing durable water repellency in silicone finishing. 

VIKON FGT is also a good hand builder for silicone water repellent finishes because it has essentially no effect on the spray rating and it is fully compatible with the silicone repellents and their catalysts. 

Naturally, leather absorbs some liquid water but mainly is water resistant. The leather industries do not claim that it is waterproof. So-called waterproof leathers are finished with water repellent agents such as organo-silicon, fluorocarbon and so on. Water absorption of leather can be tested by a static absorption method (ASTM D1815, 2000a). Cut the conditioned specimen with a circular cutter. Measure the diameter and thickness of the specimen. Calculate its volume in cubic centimetres. Weigh the specimen to the nearest 0.01 g. Immerse the specimen in distilled water at 23 1 °C in ahorizontal position with the grain side up. Leave the specimen immersed for a period of 30 min. At the end of immersion, take out the specimen and blot the surface of the specimen with filter paper to remove excess water. Weigh the specimen immediately to the nearest 0.01 g. Calculate the amount of water absorbed by the specimen ... 

The silicones have established their value as water-repellent finishes for a range of natural and synthetic textiles. A number of techniques have been devised which result in the pick-up of 1-3% of silicone resin on the cloth. The polymer may be added as a solution, an emulsion or by spraying a fine mist alternatively, intermediates may be added which either polymerise in situ or attach themselves to the fibre molecules. 

Early waterproofing treatments consisted of coatings of a continuous layer impenetrable by water. Later water-repellent fabrics permitted air and moisture passage to improve the comfort of the wearer. Aluminum and zirconium salts of fatty acids, silicone polymers, and perfluoro compounds are applied to synthetic as well as natural fibers. An increase in the contact angle of water on the surface of the fiber results in an increase in water repellency. Hydrophobic fibers exhibit higher contact angles than cellulosics but may still require a finish (142). 

Chemical modification of the wax can improve smear resistance (5). Silicones, which do not harm furniture finishes (6), are incorporated as film-forming ingredients in furniture polishes. The lubricant properties of silicones improve ease of application of the polish and removal of insoluble soil particles. In addition, silicones make dry films easier to buff and more water-repellent, and provide depth of gloss, ie, ability to reflect a coherent image as a result of a high refractive index (7). Wax-free polishes, which have silicones as the only film former, can be formulated to deliver smear resistance (8). Another type of film former commonly used in oil-base furniture polishes is a mineral or vegetable oil, eg, linseed oil. 

The single largest use of silicone resins is as water repellents for stone and masomy. The resins also find important applications in paints and finishes, especially for high-temperature use, and increasingly as additives to conventional paints. Among the numerous speciality uses which have also been developed, siloxane resins are used to coat pharmaceutical pills and as encapsulants for electronic components. 

Some effects are similar or assist each other, for example silicone elastomers cause water repellency, softeners bring about antistatic effects and antistatic finishes can be softening. 

Depending on their method of synthesis, silicone softeners can contain variable amounts of volatile siloxane oligomers. Together with volatile emulsifiers these oligomers can cause pollution problems in the waste air from tenter frames." In textile finishing, silicones are also used as water repellents, elastomeric finishes, coatings and as defoamers. 

Non-slip finishes are mostly applied by the pad-dry process, combined as needed with hand builders, repellents or cellulose crosslinkers (easy-care finish). The combination of silicic acid sols with softeners or silicone-based water repellents is crucial - their effects are contrasting. 

Although silicones give very smooth films around any kind of fibre, silicone finishes (soft handle, water repellency, stretch) may reduce the crocking fastness. 

CONDENSOL I New is a special metal salt catalyst for water-repellent finishing with the silicone product PERSISTOL SIN. 

The PERSISTOL types are supplied in the form of aqueous emulsions. They are wash-resistant water-repelling agents derived from paraffin wax or silicone and are used mainly for the water-repellent finishing of outerwear. 

Silicone resin emulsion for water-repellent finishes. 

Repellent finishes are important components of many protective textiles. Apphca-tions for repellent textiles range from medical textiles to raincoats. The low surface energies provided by repellent finishes can keep solid and liquid soils from adhering to treated fiber surfaces. Finishes based on hydrocarbon and silicone chemistries can yield water repellent textiles, while fluorochemicals are necessary to achieve the low surface energies needed for dry soil and oil repellency. "... 

It is important to note that any polymer coating sample used must be free from any silica fillers or water-repellent silicone surface treatment, otherwise interference will occur. However, most silicone finishes are applied to the outer textile face only. 

The latest development is the use of silicones for water-repellent finishes. Linear dimethyl polysiloxane ... 

The principle of blending a conduction fiber with a static-prone fiber has been known for years. A mixture of a substantial quantity (30—40%) of a hydrophilic fiber such as cotton or rayon with a hydrophobic static-prone fiber such as a polyester can produce a static-free blend under ordinary conditions. However, blocking the hydrophilic groups by cross-linking of the cotton with bifunctional reagents such as dimethylolethylene urea or addition of a water-repellent finish such as a silicone resin increases the static propensity of such a blend. 

Solnpret [HoechstAO] Silicon sol ns. water repellent finishing. 

You can also be exposed to tetrachloroethylene by using certain consumer products. Products that may contain it include water repellents, silicone lubricants, fabric finishers, spot removers, adhesives, and wood cleaners. Although uncommon, small amounts of tetrachloroethylene have been found in food, especially food prepared near a dry cleaning shop. When you bring clothes home from the dry cleaners, the clothes will release small amounts of tetrachloroethylene into the air. The full significance to human health of these exposures to small amounts of tetrachloroethylene is unknown, but to date, they appear to be relatively harmless. 

A unique fluoroepoxy compound is liquid at ambient temperature and can be cured by incorporation of suitable agents (e.g., amino silicone compounds) [2.37]. It forms finishes with low friction, oil and water repellency, and antifouling properties [2.38], [2.39]. 

Chem. Descrip. Water-based silicone elastomeric emulsion Uses Water repellent, gloss aid, mar resist, aid for water-based inks and product finishes protective water repellent coating for woven and non-woven textiles and fabrics Features Imparts water and weather resist. 

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