Non-slip finishes are easy to understand. Their practicalimportance is much greater than one might suppose from first looking at thesefew pages. Since the main effect of non-slip finishes is to increase theadhesion between fibres and yarns regardless of fabric construction, thegeneric term for these finishes would be fibre and yarn bonding finishes. Otherterms that can be used include anti-slip, non-shift and slip-proofing finishes.
Adhesion between yarns is especially important in wovenfabrics at the seams and in highly stretched areas like the elbows of shirts,blouses and jackets. Slippage of warp and fill yarns can also be a problemduring preparation, dyeing, printing and finishing. This shifting generates anunequal appearance of wovenfabrics, but the yarns are not damaged as in similar knitwear defects. Fabricelongation, moir and crack marks can be caused by a too low yarn density,under-constructed fabrics and by very smooth fibres.
Smooth fibres, such as filaments of synthetic yarn, cancause similar problems in knitted fabrics. Runs, dropped stitches and snags arefabric defects that can be attributed to lack of fibre adhesion. Common termsfor these interrelated problems are picking and snagging. The chemical productsthat reduce or eliminate these defects (anti-picking and anti-snaggingfinishes) are quite similar to non-slip finishes. Among the factors that canaffect yarn slippage are fibre type, yarn size, fabric weave, yarn count (endsand picks per square inch or centimeter), fabric weight and type of finishingprocess.
Non-slip finishes are often used with under-constructedfabrics to compensate for the reduced yarn count and to achieve acceptablephysical properties. Lining and pocketing fabrics made with smooth syntheticfilaments are finished with friction enhancers combined with durable pressagents, water repellents or hand modifiers to prevent seam slippage. Umbrellafabrics made from nylon or polyester filament yarns are treated with frictionenhancers and water repellents. The properties of any woven fabric with longfloats can usually be improved with nonslip finishes. In particular, Jacquardupholstery fabrics with long floats are stabilised by back coating with film-formingpolymers. A special variation of the non-slip finishes, often combined with the incorporation ofmetal filaments, is the stab- and stitch-resistant finish, used for protectiveclothing and furniture, for example in trains and buses.
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