Polyisoprene condoms
AssigneeLRC Products Limited
InventorsJulie Attrill, Melissa Jane Ballard, Eman Alsaffar
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Abstract
The present invention relates to processes for making synthetic polyisoprene latex and synthetic polyisoprene condoms. A process for making a compounded synthetic polyisoprene latex suitable for making a latex film comprises (a) compounding a synthetic polyisoprene latex with suitable compounding ingredients, (b) maturing the latex and optionally (c) storing the latex; characterized in that steps (a), (b) and (c) if included are carried out at a low temperature so as to minimize prevulcanization of the latex. Condoms can be made from latexes produced according to the process of the invention.
Claims28
A process for making a compounded synthetic polyisoprene latex suitable for making a latex film comprising:
- (a) compounding a synthetic polyisoprene latex with suitable compounding ingredients;
- (b) maturing the latex for at least about 24 hours;
- and optionally
- (c) storing the latex;
- wherein at least the steps (a) and (b) are carried out at a temperature of less than 20° C. so as to minimize pre-vulcanization of the latex;
- wherein an initial tensile strength of the latex is at least 24 MPa;
- and
- wherein the suitable compounding ingredients comprise an accelerator consisting of a dithiocarbamate.
A process for making a synthetic polyisoprene condom comprising:
- dipping a suitably shaped former into a compounded synthetic polyisoprene latex;
- and
- vulcanizing the latex to form a condom;
- wherein during preparation, the latex is maintained at a temperature of less than 20° C. so as to minimize pre-vulcanization of the latex, and the latex is matured for at least about 24 hours resulting in an initial tensile strength of the condom of at least 24 MPa;
- and
- wherein the compounded synthetic polyisoprene latex comprises an accelerator consisting of a dithiocarbamate.
A process for making a synthetic polyisoprene condom comprising:
- compounding a synthetic polyisoprene latex with one or more suitable compounding ingredients;
- maturing the latex for about 24 hours to about 48 hours to form a condom having at least two of the following initial properties:
- an initial tensile strength of at least 24 MPa;
- an initial burst pressure of at least 1.3 kPa;
- an initial burst volume of at least 44 dm3;
- and
- an initial elongation-at break value of at least 1000%;
- wherein the compounding and maturing steps are carried out at a temperature of less than 20° C.;
- and
- wherein the one or more suitable compounding ingredients comprises an accelerator consisting of a dithiocarbamate.
Dependencies are inferred from the claim text.