TPT January 2011

T echnology U pdate Anodising and coating

series chrome-free pre-treatment processes help producers maximise adhesion and corrosion protection. Both Gardobond X 4707 and Oxsilan AL 0510 hold Qualicoat approvals. Gardo TP 10748, an additive for alkaline etching, offers improvements for E-6 etching concerning rinsing and draining behaviour (ie low viscosity in the E-6 bath), homogeneity and matt finish (gloss readings 6-8 achievable, 60° test), increased productivity (batch optimisation), and avoidance of surface defects caused by special alloy composition. Chemetall’s new Topseal hot-sealing product series consists of three different processes adapted to users’ anodising plants: Topseal Gardo TP 10769 for use in baths without filtration; TP 10779 for use in baths with filtration through a filter pump; and TP 10792/TP 10793 for use in baths with filtration, optimised to reach longer bath life circles. When optimally used, products of the Topseal Gardo series are claimed to achieve weight loss values of 10-15mg/dm². All products can be analysed online or in Chemetall’s laboratory. Chemetall Topseal prevents the formation of sealing smut, gives clean, smut-free surfaces and offers

benefits especially on coloured surfaces. Chemetall’s Gardoclean T 5281 is a completely borate-free aluminium cleaner. The product is liquid and so is easy-to- use. It provides good cleaning results at temperatures below 60°C (depending on condition of parts) and automatic dosage is possible. Gardoclean T 5281 has been specifically designed for cleaning aluminium both in the anodising and pre-treatment processes. Chemetall GmbH – Germany Fax: +49 69 7165 3428 Website: www.chemetall.com

AT the 2010 Aluminium Trade Fair in Essen, Germany, Chemetall showcased its Gardobond ® X and Oxsilan ® AL products – new chrome-free solutions for the pre- treatment of aluminium, and the Gardo ® TP 10748 and Gardo Topseal products for anodising processes, as well as the completely borate-free aluminium cleaner Gardoclean ® T 5281. For many years, hexavalent chrome pre-treatment has been the standard for aluminium. More recently, chrome-based pre-treatment processes have come under pressure for environmental and health and safety reasons. The first chrome-free pre- treatment processes started to appear in the marketplace about 20 years ago. Today, with almost two decades of operating experience gained, and hundreds of users worldwide, the performance of these programmes is said to be equivalent to the ‘old’ hexavalent chrome products. Chemetall’s Gardobond X and OxsilanAL

Clear Gardobond X 4707 bath

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J anuary 2011

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