New from J H Lowenstein

Three new Lowatan products have been released by J H Lowenstein, USA: Lowatan AB is a highly concentrated acid enzyme bate based on the enzyme pepsin and is active at pH2.8-3.8. It is recommended for 'slackening' wet-blue and vegetable crust materials. It penetrates rapidly due to the enzyme's high solubility rate, making the leather softer and with a smoother grain. Lowatan AB dissolves and removes all excess 'gelatinous protein' from the fibres of the hide, thereby enabling the leather to become more 'breathable'. It also helps chemicals to penetrate more rapidly and effectively, produces leathers which are lighter in weight and greater in area yield and improves uniformity and penetration of dyes. In general, 0.5-3% Lowatan AB is applied to wet-blue material (calculated on shaved weight). For a proper 'slackening process' float pH should be adjusted to 2.8-3.0 and maintained within these parameters for a minimum of one hour. Lowatan AS is a special aluminium containing tanning/retanning agent for all types of leather. It is based on aluminium salts and amphoteric condensation products and is recommended for tanning with chrome of raw stock that has a tendency to sponginess and loose grain. The product forms a hybrid with Lowatan CR or chrome producing soft tannage with compact structure and tight grain. It is applicable for retanning all types of leather. It can also be used in the pretanning stage for wet-white leather. Only a small amount of product is required for stabilising the pelt for splitting and shaving (shrinkage temperature is 75°C). With its high basicity, Lowatan AS has a strong affinity for anionic dyes, resulting in deeper and fuller shades. The fastness properties of dyeings are greatly improved. Special attention should be paid to the stability of anionic products (especially fatliquors) in the presence of Lowatan AS. Lowatan TS is a tanning/retanning agent for non-metal tannage for all types of leather. Lowatan TS is based on special vegetable extracts and amphoteric condensation products and is recommended for non-metal (non-chrome) tanning of upholstery leathers. The product is usually applied as a main tanning agent in the system. Lowatan TS can also be used in the pretanning stage for wet-white leather. Only a small amount is needed for pelt stabilisation for splitting and shaving (shrinkage temperature 75°C). It is also suitable for retanning all types of leather, fills the leather especially in areas where the fibre structure tends to be loose and produces leather with good lightfastness.