Crepe rubber

Crepe rubber is coagulated latex that is rolled out in crinkled sheets, commonly used to make soles for shoes and boots but is also a raw material for further processed rubber products.

Colloidal latex is first mixed with formic acid to cause it to coagulate. The coagulum is processed in a "creping battery", a series of machines that crush, press and roll the coagula. The sheets are hung in a heated drying shed and then sorted by grade and packed for shipping.

There are several types and grades of rubber crepe, mainly distinguished by the grade and pre-processing of the latex used in their manufacture.

Hand-powered latex creping machines

Removing coagulum from coagulating troughs

Creping battery

Milling honey colored crepe

Milling white crepe

Spooling crepe from last finishing mill

Smooth crepe spooled for transfer to drying shed

Wet coagulum crepe blanket

Smallholder's sheet in drying shed

White crepe hanging in drying shed

Laminating white crepe for sole crepe

Laminating honey colored crepe for sole crepe

Sole crepe inspection and packing

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Wikipedia