Sika Technology Ag

Sika Schweiz Ag

Reto Dohner

Michael Schlumpf

Wolf-Rüdiger Huck

Dana Maiwald

Wolf-Rudiger Huck

Reto Koch

Britta Studiger

Sara Fornera

Stefan Egli

Andreas Diener

An aqueous composition including: a) at least one epoxy silane containing at least one epoxy group and at least one hydrolysable group bound to Si, b) at least one non-ionic wetting agent and either c1) between 0.2 and 2 wt. % of at least one mercapto silane containing at least one mercapto group and at least one hydrolysable group bound to Si, and as many water-soluble acids as required for the pH of resulting composition to be between 1 and 6, on the condition that epoxy silane content amounts to between 0.2 and 1 wt. %, or c2) between 0.1 and 1 wt. % of a water-soluble organotitanate, in relation to entire weight of aqueous composition, and as many water-soluble bases as required for the pH of resulting composition to be between 8 and 14, on the condition that the epoxy silane content amounts to between 0.2 and 0.5 wt. %.

Aqueous pretreatment for bonded joints with increased heat stability

An adhesive system, having an adhesion promoter composition, containing at least one mercaptosilane, at least one polysilane, at least one transition metal complex having substantially only monodentate ligands, and at least one non-alcoholic solvent, and an adhesive, wherein the adhesive, within an hour after application and storage at 23&#xb0; C. and 50% relative air humidity, has a tensile shear strength of at least 3 MPa, as measured according to ISO 4587, and/or, within an hour after application and storage at 23&#xb0; C. and 50% relative air humidity, has at least 50%, preferably at least 60%, of the tensile shear strength achievable after application and storage for 7 days at 23&#xb0; C. and 50% relative air humidity, as measured according to ISO 4587. An adhesion promoter system has a liquid container having a manually actuable output apparatus, and an adhesion promoter composition, as disclosed above.

Adhesive system with highly reactive pretreatment agent

Embodiments of the present application relate to a composition including A) at least one aminosilane which has at least one hydrolyzable group bonded to Si, B) at least one mercaptosilane which has at least one hydrolyzable group bonded to Si, and C) at least one emulsifier selected from pyrrolidones, propionamides and amino alcohol reaction products, wherein, if at least one amino alcohol reaction product is used as an emulsifier, an amino alcohol and at least part of the aminosilane and/or mercaptosilane are contained in the form of an amino alcohol reaction product, in which at least some of the hydrolyzable groups present in the at least one aminosilane and the at least one mercaptosilane are replaced by the amino alcoholate group of the amino alcohol, D) and/or hydrolysis and/or condensation products of the silanes contained.

Pretreatment having improved storage stability and adhesion

A thermally cured silicon coating on a plastic, in particular a thermoplastic, can be adhesively bonded without use of an adhesive primer. Such thermally cured silicon coatings are produced by a process including: application of a silicon composition to the surfaces of a plastic or to the surface of a plastic treated with a plastic primer; air drying of the silicon composition to form a silicone film; baking at a temperature in the range from 80&#xb0; C. to 200&#xb0; C.; and application of a bonding agent composition to the silicone film during baking or during the phase of cooling to ambient temperature after baking.

Thermally cured silicone coating which can be adhesively bonded without primer

The invention relates to a static mixer () having a cylindrical mixer channel formed by a mixer channel housing () and a multistage mixer blade element () which is disposed in said mixer channel and used for mixing layers of hardening accelerator paste in a stream of highly viscous PU. Discharge openings () are provided in the inlet area of the static mixer. Said discharge openings introduce a partial stream of hitherto unmixed highly viscous PU into. secondary channels () disposed parallel to the mixer channel. The secondary channels are connected to feeder openings () disposed in the wall of the mixer channel downstream of the mixer wing element () when viewed in the direction of flow. The unmixed PU is guided in the secondary channels () and enters the outer area of the stream coming from the mixer wing element via the feeder openings where the mixed layers of hardening accelerator paste are contained. The mixed stream is jacketed with a layer of unmixed PU to prevent layers of hardening accelerator paste from being discharged from an adhesive element applied with the aid of the mixer () and to prevent the occurrence of adhesive defects resulting therefrom.

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Zurich, Switzerland

Reto Dohner