Patent

A solid cyanoacrylate adhesive composition is disclosed which can be applied to a substrate in solid form and which polymerizes into an adhesive polymer upon liquefying. Preferably the solid cyanoacrylate composition liquefies at temperatures slightly above room temperature and polymerizes upon liquification. -caprolactones are used as a solidifying polymer with cyanoacrylate monomers and other additives to form the solid cyanoacrylate adhesive composition.

The invention comprises compounds of the formula <1048906><1048906><1048906><1048906><1048906><1048906><1048906>

A process for preparing methyl .alpha.-cyanoacrylate in which methyl cyanoacetate is reacted with formaldehyde to form a polymer, which is subsequently depolymerized to the monomeric product, comprises using an ester of poly(ethylene glycol) as the solvent for the polymerization and depolymerization reactions.

Prepn. of methyl alpha-cyanoacrylate comprises reacting methyl cyanoacetate with HCHO in a solvent of a poly(ethylene glycol)di-acetate, dipropionate, or dibutyrate, having a number average molecular wt. of 200-400. The formed polymer is then depolymerised to the monomeric prod. the purity of yield is 96% or better.

a-cyanoacrylate compounds expressed by the following general formula: wherein R' desianates- and R2 designates alkyl groups, alkenyl groups or alkynyl groups of C1 to C4. These compounds are preferably synthesized by the reaction of the compounds expressed by the following general formula: wherein R' and R2 are same as the above described, with formaldehyde products and then the depolymerization of the resulting dehydrating condensation polymers. These compounds are effectively used as fast-setting adhesives.

This invention is related to the preparation of alkyl or alcoxyalkyl-&agr;-cyanoacrylates in monomeric form by depolymerisation of the corresponding poly(alkyl-&agr;-cyanoacrylates) or poly(alcoxyalkyl-&agr;-cyanoacrylates) (PCA). The PCA's are obtained preferably by base-catalyzed condensation of a cyanoacetate with formaldehyde (or a polymer of the latter).

A method is disclosed for the catalytic polymerization of cyanoacrylate monomers by contacting said monomers with an organotin compound. Also included is a polymerizable system comprising cyanoacrylate monomer and an organotin compound, wherein upon contact of the monomer and the compound, the compound catalyzes the polymerization of the monomer.

A fingernail adhesive including a mixture of less than 1 % halogen-nitropropane as a fungicide and a cyanoacrylate adhesive. Preferably the halogen-nitropropane is bromo-nitropropane and the cyanoacrylate adhesive is selected from the group consisting of isopropyl, ethyl and methyl cyanoacrylate and mixtures thereof.

A process, requiring minimal skills, for applying a protective acrylic coating, with or without extending the tips, to the human fingernail as afforded by (1) clearing and roughening the surface of the nail, (2) applying a layer of liquid acrylic monomer, (3) applying a powdered polymethacrylate ester to the wetted nail surface, (4) removing loose powder and smoothing the nail surface, (5) brushing on, as one would with nail polish, a second layer of liquid acrylic monomers and, after curing, (6) finishing the nail in the conventional manner.

An artificial fingernail material is disclosed. It contains base-treated bone powder of a particular particle size in a curable adhesive. A process for applying this material to the nail by applying an adhesive, adding bone powder and repeating as needed is disclosed as is the process for preparing the particular bone powder.