Process for the manufacture of frictional elements and frictional elements produced thereby
OwnerPeter H. R. B. Lemon, Michael Toweyinventors
Life of this patent
Estimating the term…
Abstract
A method for the manufacture of shaped frictional elements is provided. The method comprises mixing a first portion of a frictional filler with from 5% to 30% of certain liquid, alkaline, phenol-formaldehyde resins; mixing a second portion of the same or a different frictional filler with a liquid ester curing catalyst for the phenyl-formaldehyde resin; intimately mixing the first and second portions; and allowing the resultant mixture to cure in a mould. A composition comprising a frictional filler, the above resin, and a curing catalyst is also provided. The disclosed method is quick and economical and is carried out at room temperature without the hazards and inconveniences associated with heated moulds.
Claims18
A method for the manufacture of a shaped frictional element, comprising:
- (a) mixing a first portion of a frictional filler with from 5% to 30% of a liquid, alkaline, phenol-formaldehyde resin having a formaldehyde:phenol molecular ratio between 1:1 to 3.5:1, a weight average molecular weight (Mw) between 300 and 4,000 and an alkali metal hydroxide to phenol molar ratio of from 0.1:1 to 5:1, and a pH greater than 10;
- (b) mixing a second portion of the same or a different frictional filler with an effective amount of a liquid ester curing catalyst for the resin of step (a);
- (c) intimately mixing said first and second portions together to form a mixture;
- and
- (d) allowing the resultant mixture to cure in a mold.
A composition suitable for the manufacture of brake linings, brake pads, and clutch facings comprising:
- (a) a major portion of (frictional) filler selected from the group consisting of copper powder, iron wool, iron powder, iron filings, and mixtures thereof;
- (b) from 5% to 30% of a liquid, alkaline, phenol-formaldehyde resin having a formaldehyde to phenol molecular ratio of between 1:1 to 3.5:1, a weight average molecular weight (M.sub.w) of from 300 to 4000, and an alkali metal hydroxide to phenol molar ratio of from 1:1 to 5:1, and a pH greater than 10;
- and
- (c) from 10% to 110% based on the weight of the resin of an ester curing catalyst.
Dependencies are inferred from the claim text.