Seeking Polishing Technology For Faceted Glass

• A manufacturing process
• A material
• A technology
• A partner

A SpecialChem Client is seeking to improve or substitute their polishing process with a new stable manufacturing process which results in a high-quality polish of small faceted glass with low production costs and a fast execution time for a high volume of stones.

The current process for polishing faceted glass surfaces used by the SpecialChem Client is Tribochemical planarization utilizing the combination of chemical and mechanical forces, i.e. an interaction of both the surface of the faceted glass stones and the polishing material with water, as well as significant friction / mechanical pressure. The optimal polishing material currently in use is Cerium Oxide due to its strong grip and ability to polish glass using both chemical and mechanical forces simultaneously.

The SpecialChem client’s polishing substrates are faceted glass stones ranging from 1mm to 25mm in diameter, with ~ 12 facets per stone. The facet sizes range from 1mm² to 100mm², at times up to 50mm x 50mm.

The client’s polishing process follows separate Rough and Fine Grinding process steps as shown:

Forming >> Rough Grinding >> Fine Grinding >> Polishing >> Surface Effects

Following Fine Grinding, surface roughness is in the range from 2 to 7 µm (Rt, i.e. standard deviation of surface roughness prior to polishing). The Polishing step initially smoothens the rugged peaks and surface irregularities using primarily mechanical force. A coolant (water) is then applied to the glass surface loosening the glass surface to allow the chemical absorption and decomposition induced by the polishing material to take effect. The polishing grains are then flattened by tangential shear abrasion between the polishing disc and glass surface, exploiting the chemical bond between the glass surface and the polishing grain, conclusively allowing the removal of the top layer of the glass surface at a removal rate of >1µm/s.

Current process parameters include variations in polishing pressure, relative velocity (speed), accurate stone positioning, traversing movement, and polishing material (composition; chemical / physical properties, including but not limited to hardness; grain composition and size; polish concentration and structure), however the client is also seeking solutions which focus on an entirely new process rather than parameter variations.

An improvement or alternative to our current manufacturing process should be a cost effective solution yielding savings in overall production costs which can be then passed on to our customers.

The SpecialChem Client is seeking a solution which meets the following requirements:

1. Polishing Speed: Polishing removal rate after the elimination of rough surface of glass material should be >1µm/s @ 1 N/mm².
2. Surface Quality / Planeness: Plane facets should be length of facet (for small facets, 2mm x 1mm); faceted edges must be maintained.
3. Surface Quality / Roughness: should be (Rq i.e. standard deviation of surface roughness after polishing) (no visible polishing direction, scratch or markings).
4. Polishing Time: should be

Chemical, mechanical or a hybrid solution should be considered. All proposed solutions should consider consumption efficiency of the polishing material and energy costs (in terms of total production costs).

The SpecialChem Client is open for plausible solutions which could very well imply an extreme change to their entire production process (simplification or removal of unnecessary process steps).

• Ideas
• Concepts
• Proven Concepts
• Ready-to-use solutions
• Partners

• Industry: Various
• Annual Revenue: $Billion
• Years in Business: More than 20 years
• Headquarters Area: Europe

• Licensing
• Contractual partnership (R&D, marketing…)
• Joint-venture
• Buying