Abstract: A method of forming a component for a droplet deposition apparatus, includes the steps of: providing a protection material so as to fill fluid chambers and; directing a high-powered laser at the component so as to ablate an array of nozzles communicating with respective filter chambers. The protection material acts to inhibit damage to the walls of the chamber during ablation, such as damage to the interior passivation coating, or electrodes provided on the walls of the chamber, and can be removed for example by flushing with a heated solvent.

Abstract: Organoclay materials formed by reacting smectite clays with a quaternary ammonium compound are improved by controlling the pH of the reaction mixture, typically to a value in the range 8 to 10, and preferably 9.0.+-.0.5, and by including in the reaction mixture a further substance, such as urea or sulphamic acid, having an unsubstituted or substituted amino or amido group.