Patent GB-411032-A (GB)
Title: Improvements in the manufacture of articles from rubber compositions
IPC: C08L21/00
Filed: 1933-11-14
Abstract: Rubber and hard rubber articles parts of which are non porous and the remaining parts microporous are produced by moulding a microporous gel containing at least 10 per cent of sulphur measured on the dry rubber content, to the required shape, drying those parts which are to become non-porous while preventing the escape of water from those parts which are to remain microporous. The article is then vulcanized under such conditions that the microporosity of the undried parts is maintained.  In order to provide a sharp line of division between the porous and microporous parts, pressure is applied to the gel, e.g. by tightening a noose round it, before any drying has taken place. An example of a filter for use in filtering artificial silk on its way to spinning nozzles is a hollow cylinder closed at one end, the lower half of which is microporous and the upper half non-porous having the hardness of ebonite, and being provided with a cut or moulded screw thread.  The filter can be screwed into a vessel and the artificial silk solution forced into the interior and filtered through the pores in the lower half.  Filters can also be made which will only filter at certain points along their length or circumference.ALSO:Rubber and hard rubber articles parts of which are non porous and the remaining parts microporous, are produced by moulding a microporous gel containing at least 10 per cent of sulphur measured on the dry rubber content, to the required shape, drying those parts which are to become non porous while preventing the escape of water from those parts which are to remain microporous. The article is then vulcanized under such conditions that the microporosity of the undried parts is maintained.  In order to provide a sharp line of division between the porous and microporous parts, pressure is applied to the gel e.g. by tightening a noose round it, before any drying has taken place. An example of a filter for use in filtering artificial silk on its way to spinning nozzles is a hollow cylinder closed at one end, the lower half of which is microporous and the upper half non porous having the hardness of ebonite, and being provided with a cut or moulded screw thread.  The filter can be screwed into a vessel and the artificial silk solution forced into the interior and filtered through the pores in the lower half.  Filters can also be made which will only filter at certain points along their length or circumference.ALSO:Rubber and hard rubber articles parts of which are non-porous and the remaining parts microporous, such as filter pipes, oil filters and electrolytic diaphragms are produced by moulding a microporous gel containing at least 10 per cent sulphur measured on the dry rubber content, to the required shape, drying those parts which are to become non-porous while preventing the escape of water from those parts which are to remain microporous.  The article is then vulcanized under such conditions that the microporosity of the undried parts is maintained. In order to provide a sharp line of division between the porous and microporous parts, pressure is applied to the gel, e.g. by tightening a noose round it, before any drying has taken place. An example of a filter for use in filtering artificial silk on its way to spinning nozzles is a hollow cylinder closed at one end, the lower half of which is microporous and the upper half non-porous having the hardness of ebonite, and being provided with a cut or moulded screw thread.  The filter can be screwed into a vessel and the artificial silk solution forced into the interior and filtered through the pores in the lower half.  Filters can also be made which will only filter at certain points along their length or circumference.