Mold release coating process and apparatus using a supercritical fluid

The process comprising the steps of:

• a. forming a fluid mixture in a closed system, said fluid mixture comprising:
• i. at least one release agent capable of forming a thin layer or coating on a mold surface,
• ii. at least one supercritical fluid, and
• iii. optionally, a reduced amount of an active solvent or solvent(s) capable of dissolving, suspending or dispersing the release agent;
• b. spraying said fluid mixture onto a mold surface to form a thin layer of the release agent thereon;
• c. introducing a molding composition to the mold surfaces containing the thin layer of release agent thereon and molding the composition in the mold to form a molded product;
• and
• d. separating the molded product from the mold.

A molding process which comprises:

• a. forming a fluid mixture in a closed system, said fluid mixture comprising:
• i. at least one wax compound capable of forming a layer on the mold surface,
• ii. at least one supercritical fluid, and
• iii. optionally, a reduced amount of an active solvent or solvent(s) capable of dissolving, suspending or dispersing the wax compound(s);
• b. spraying said fluid mixture onto a mold surface to form a thin wax layer thereon;
• c. introducing a molding composition to the mold surfaces containing the thin wax layer of release agent thereon and molding the compositions to form a molded product;
• and
• d. separating the molded product from the mold.

A molding process which comprises:

• a. forming a fluid mixture in a closed system, said fluid mixture comprising:
• i. at least one wax compound capable of forming a layer on the mold surface,
• ii. at least one supercritical fluid, and
• iii. optionally, a reduced amount of an active solvent or solvent(s) capable of dissolving, suspending or dispersing the wax compound(s);
• b. spraying said fluid mixture by electrostatic means onto a mold surface to form a thin wax layer thereon;
• c. introducing a molding composition to the mold surfaces containing the thin wax layer of release agent thereon and molding the compositions to form a molded product;
• and
• d. separating the molded product from the mold.

A process for the release preparation of mold surfaces in which the polymerization of an active hydrogen compound and an isocyanate compound is carried out to form a molded article conforming to the mold, wherein the mold surfaces are release prepared prior to said polymerization by the process which comprises:

• a. forming a fluid mixture in a closed system, said fluid mixture comprising:
• i. at least one wax compound capable of forming a layer on the mold surface,
• ii. at least one supercritical fluid, and
• iii. optionally, a reduced amount of an active solvent or solvent(s) capable of dissolving, suspending or dispersing the wax compound(s);
• and
• b. spraying said fluid mixture onto a mold surface to form a wax layer thereon.

An apparatus for the deposition of a release agent mixture comprising a supercritical fluid and a release agent onto a release surface which comprises:

• a. means for forming a supercritical fluid,
• b. heating means for reducing the viscosity of a release agent,
• c. means for combining the release agent and the supercritical fluid into a release agent mixture and maintaining the release agent mixture in the supercritical fluid state, and
• d. means for spraying the release agent mixture in the supercritical state onto a release surface, and
• e. a release surface onto which the release agent mixture is deposited.