Patent ID: 11938231
Assignee: SMITH & NEPHEW PLC
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 11:
12. A method of preparing a sterile packaged curable composition selected from a wound packing material or filler which can be configured to the shape of a wound or an adhesive or sealant for a wound dressing, wherein the composition is an RTV (Room Temperature Vulcanization) composition which comprises two or more Parts, which is apportioned between at least one Part A and at least one Part B, the method comprising:
preparing a composition comprising:
(i) one or more alkenyl-containing prepolymers having at least one alkenyl moiety per molecule,
(ii) one or more SiH-containing prepolymers having at least one SiH unit per molecule, and additionally:
(iii) a catalyst for curing by addition of the alkenyl-containing prepolymer of (i) to the SiH-containing prepolymer of (ii),
wherein Part A incorporates an amount of the one or more alkenyl-containing prepolymers of (i), wherein the one or more alkenyl-containing prepolymers of (i) comprises one or more polydiorganosiloxane prepolymers having at least one organoalkenylsiloxane unit per molecule, and additionally the catalyst of (iii) for curing by addition of the prepolymer of (i) to the prepolymer of (ii), wherein Part A does not include the prepolymer of (ii); and
wherein Part B incorporates an amount of the one or more alkenyl-containing prepolymers of (i), wherein the one or more alkenyl-containing prepolymers of (i) comprises one or more polydiorganosiloxane prepolymers having at least one organoalkenylsiloxane unit per molecule, together with the one or more SiH-containing prepolymers having at least one SiH unit per molecule of (ii), wherein the one or more SiH-containing prepolymers having at least one SiH unit per molecule comprises one or more polydiorganosiloxane prepolymers having at least one organohydrogensiloxane unit per molecule; wherein the volume and viscosity of Parts A and B may be approximately equal; wherein Part B does not include the catalyst of (iii);
wherein the composition is non-foamable or is foamable comprising (iv) a blowing agent, selected from any agent which evolves gas or vapour as part of or during the curing reaction; and
wherein the at least one Part A and at least one Part B are provided within or upon at least two respective receptacles or supports, and are adapted to be dispensed or released therefrom in cooperative manner facilitating intimate contact and curing thereof, wherein the receptacle(s) or support(s) and the at least one of Part A and Part B are thermally stable at elevated temperature of 123° C. for a period in excess of 18 hours wherein the composition is sterilised in a conventional oven or autoclave at ambient or elevated pressure with steam present, but the manner of packaging is resilient to steam penetration and thereby prevents steam contacting the composition directly, whereby the effective sterilization is a dry heat sterilization;

sealing the Part(s) A and Part(s) B in receptacles with barrier means in a manner to prevent contamination thereof.