Abstract: An alpha tocopherol is disclosed as a polymerization inhibitor effect against (meth)acrylate monomer polymerization in nail extension liquids. Alpha-tocopherol was found to inhibit polymerization of ethyl methacrylate.

Abstract: In the disclosed method for the reshaping (adornment, repair, covering, prosthetic extension, etc.) of essentially rigid, keratinaceous surfaces such as nail plates with a free radical-polymerizable acrylic ester, the free radical initiator comprises a compound of the formula III ##STR1## wherein R.sup.1 through R.sup.4 are hydrogen, an aliphatic group, an aromatic group, a cycloaliphatic group, or, less preferably, a sulfhydryl group, an alkali or alkaline earth metal salt of a sulfhydryl group, a halogen, or amino group; or R.sup.3 or R.sup.4 can be an alkali metal or alkaline earth metal cation when the 5-carbon is negatively charged. The compound of formula III, in chemically-curable systems is utilized in combination with a metal salt cocatalyst and, optionally, an organic buffering compound and a crosslinker.

Abstract: A method for improving--with an adhesion-promoting composition--adhesion of a synthetic monomeric or polymeric material (such as a curable acrylic monomer/polymerized acrylic system) to a keratinaceous substrate, as in, for example, the reshaping of fingernails or toenails. The adhesion-promoting composition comprises (A) an organic, dipolar, aprotic liquid carrier and, uniformly distributed throughout said liquid carrier, (B) pyromellitic dianhydride glycerol dimethacrylate adduct ("PMGDM"). The PMGDM isomer mixture which typically results when pyromellitic dianhydride is reacted with glycerol dimethacrylate is preferred, particularly in view of its high solubility in solvents of relatively low toxicity (e.g. lower aliphatic ketones). The adhesion-promoting composition can, if desired, be included in a nail-reshaping kit containing the materials and implements needed to reshape the nail plate.

Abstract: The disclosed method for making hollow shells (e.g. housing for in-ear hearing aids) employs a radiation-curable polymer comprising (a) a major amount of urethane methacrylate monomer (molecular weight 360-950) having a viscosity less than about 15,000 cps at 25.degree. C., (b) a viscosity-adjusting minor amount of unreacted hydroxyalkyl-methacrylate monomer, (c) a photoinitiating amount of a photoinitiator of the formula Ar.sup.1 --CO--C(OR).sub.2 --R', where Ar.sup.1 is aryl (e.g. phenyl), R is C.sub.1 -C.sub.4 -alkyl (e.g. methyl), and R' is hydrogen or alkyl or, preferably, aryl, and, optionally, (d) a coloring agent, e.g. a pigment concentrate. Viscosity control is of major importance; so the curable composition is generally solvent-free and free of viscosity-modifying solids (other than coloring agents). Acrylates (as distinct from methacrylates) are also omitted. The fully-formulated, curable composition is easily pourable and has a viscosity of less than about 2,000 cps.