Abrégé

The invention concerns a process for tanning hide to obtain leather. The general process for obtaining the intermediary wet blue stage comprises the following steps: a) a picking step with acid and salt, followed by b) a tanning step with chromium salt, followed by c) a basification step. The invention is characterized in that between step b) and c), a re-acidification step with organic acids is added. In particular the organic acids are selected from glutaric acid (GA), 2-methyl glutaric acid (MGA), succinic acid, ethyl succinic acid (ESA), adipic acid (AA), maleic anhydride, fumaric anhydride, tricarboxylic acids, hydroxycarboxylic acids, and mixture thereof. This invention enables an increase of the up-taking of the re-tanning products and provides leather with improved mechanical properties.

Classes IPC  ?

• C14C 3/06 - Tannage minéral au chrome
• C14C 1/08 - Élimination de la chauxFoulageMise en juséeDégraissage

Abrégé

The invention concerns a process for tanning hide to obtain leather. The general process for obtaining the intermediary wet blue stage comprises the following steps: a) a picking step with acid and salt, followed by b) a tanning step with chromium salt, followed by c) a basification step. The invention is characterized in that the bath of the pickling step comprises organic acids selected from 2-Methyl glutaric acid (MGA), ethyl succinic acid (ESA) and mixture thereof instead of the traditional strong acid, generally sulfuric acid This process requires less basification agent and enables an increase of the up-taking of the re-tanning products. This invention provides leather with improved mechanical properties.

Classes IPC  ?

• C14C 3/06 - Tannage minéral au chrome
• C14C 1/08 - Élimination de la chauxFoulageMise en juséeDégraissage

Abrégé

The use of thermoplastic polymers for the preparation of injection-molded articles and the resulting articles are described. Also described, is the use of a lubricated polyamide, obtained by means of the addition of at least one lubricant during the polyamide polymerization method, for the preparation of injection-molded articles.

Classes IPC  ?

• B29C 45/00 - Moulage par injection, c.-à-d. en forçant un volume déterminé de matière à mouler par une buse d'injection dans un moule ferméAppareils à cet effet
• B29B 9/12 - Fabrication de granulés caractérisés par la structure ou la composition
• C08G 69/16 - Procédés de préparation
• C08G 69/28 - Procédés de préparation
• C08J 3/20 - Formation de mélanges de polymères avec des additifs, p. ex. coloration
• C08L 77/02 - Polyamides dérivés des acides oméga-aminocarboxyliques ou de leurs lactames
• C08L 77/06 - Polyamides dérivés des polyamines et des acides polycarboxyliques
• C08K 5/00 - Emploi d'ingrédients organiques
• B29K 77/00 - Utilisation de polyamides, p. ex. polyesteramides, comme matière de moulage
• C08K 5/01 - Hydrocarbures
• C08K 5/09 - Acides carboxyliquesLeurs sels métalliquesLeurs anhydrides
• C08K 5/098 - Sels métalliques d'acides carboxyliques

Abrégé

A method for preparing a lubricated thermoplastic polymer, in particular a lubricated polyamide is described. A method for preparing a lubricated thermoplastic polymer, in particular a lubricated polyamide, according to which a mixture of lubricants is added to the molten polymer during the polymerization process is also described.

Classes IPC  ?

• C08K 5/09 - Acides carboxyliquesLeurs sels métalliquesLeurs anhydrides
• C04B 35/634 - Polymères
• C08K 5/01 - Hydrocarbures
• C08K 5/098 - Sels métalliques d'acides carboxyliques
• C08G 69/26 - Polyamides dérivés, soit des acides amino-carboxyliques, soit de polyamines et d'acides polycarboxyliques dérivés de polyamines et d'acides polycarboxyliques
• C08G 69/28 - Procédés de préparation
• C10M 169/04 - Mélanges de matériaux de base et d'additifs