Thiol modified acylphosphine oxide photoinitiators exhibiting improved smell and extractability are disclosed. Also disclosed is a UV curable inkjet ink containing an acylphosphine oxide photoinitiator and a polymerizable compound, wherein the acylphosphine oxide photoinitiator includes one or more acyl groups substituted by a thiol.

The present invention provides a process for the preparation of mono- and bisacylphosphanes based on formula (I): ##STR00001##
as well as for their corresponding oxides or sulfides. The present invention further relates to photoinitiators obtainable by said process.

A wetness-retaining ophthalmic lens material comprises an organic monomer, a cross-linking agent, an initiator, a salt, and a solvent. The salt dissolves in the water dissociates a plurality of anions and cations, which bind to water molecules and retard the evaporation of the water molecules, the ophthalmic lens material thus can keep wet for a long time. An ophthalmic lens made of the ophthalmic lens material is also provided.

An aqueous curable composition includes a water-soluble photopolymerization initiator having a structure in which one or more carbonyl groups further directly bond to an aromatic ring of an aromatic acyl group that bonds to a phosphorus atom in an acylphosphine oxide structure, water, and a polymerizable compound. A novel water-soluble photopolymerization initiator is a compound represented by formula 1-1 or formula 2-1.

##STR00001##

Compounds represented by the following Formula I:

##STR00001##

wherein:
R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 are the same or different and are selected from the group consisting of SIL.sub.1-X, hydrogen, C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.8 alkenyl, C.sub.5-C.sub.8 cycloalkyl, phenyl C.sub.1-C.sub.3 alkyl, and fluorine; X is optional, and if present is C.sub.1-C.sub.12 alkyl; SIL.sub.1 has the general formula:

(R.sup.7SiO.sub.3/2).sub.a(R.sup.7.sub.2SiO.sub.2/2).sub.b(R.sup.7.sub.3SiO.sub.1/2).sub.c wherein: R.sup.7 is selected from the group consisting of C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.8 alkenyl, C.sub.5-C.sub.8 cycloalkyl, alkoxyl, phenyl, and phenyl C.sub.1-C.sub.3 alkyl; a is a positive number, b is 0 or a positive number, c is 0 or a positive number, b/a is from 0 to 100, and c/a is from 0 to 10, wherein at least one of R.sup.1, R.sup.2, R.sup.3, R.sup.4, and R.sup.5 is SIL.sub.1-X; and
R.sup.6 is selected from the group consisting of C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.8 alkenyl, C.sub.5-C.sub.8 cycloalkyl, phenyl, phenyl C.sub.1-C.sub.3 alkyl, trimethylphenol, and fluorine,
a method to produce these compounds, and the use thereof as a photoinitiator.

A compound capable of providing a composition having high storage stability without reacting with a base-reactive compound, even when stored in a mixed state with the base-reactive compound, as well as capable of generating a strong base by irradiation of light (active energy rays) or heating. A base generator comprises the compound and a base-reactive composition comprises the base generator and the base-reactive compound. The compound is represented by the general formula (A).

A photopolymerization initiator which is a compound having a structure in which one or more carbonyl groups that link to a carbon atom are further directly bonded to an aromatic ring of an aromatic acyl group that bonds to a phosphorus atom in an acylphosphine oxide structure. A producing method of a photopolymerization initiator produces the photopolymerization initiator. In a polymerizable composition and an ink jet recording method, the photopolymerization initiator is used. Furthermore, an acylphosphine oxide compound has a partial structure represented by Formula 1 or Formula 2.

##STR00001##

A wetness-retaining ophthalmic lens material comprises an organic monomer, a cross-linking agent, an initiator, a salt, and a solvent. The salt dissolves in the water dissociates a plurality of anions and cations, which bind to water molecules and retard the evaporation of the water molecules, the ophthalmic lens material thus can keep wet for a long time. An ophthalmic lens made of the ophthalmic lens material is also provided.

A process for the preparation of a polymer nanoparticle by a photoinduced emulsion polymerization includes preparing an emulsion comprising at least one surfactant, a dispersed phase and a continuous phase. The dispersed phase comprises at least one polymerizable monomer and the continuous phase comprises water and at least one photoinitiator. The at least one polymerizable monomer is polymerized by exposing the emulsion to an electromagnetic radiation having a wavelength so as to induce a generation of radicals from the at least one photoinitiator. The at least one photoinitiator is selected from at least one compound of formula (I) ##STR00001##

The present invention is directed to energy curable inkjet inks or coating compositions, comprising Michael addition reaction products of primary and secondary alkanolamines with stoichiometric excesses of polyacrylates. Furthermore the inks and coating compositions contain less than 2.5% by weight phosphine oxide photoinitiators. The compositions are intended for the printing of food packaging, pharmaceutical packaging, cosmetics and personal care packaging, or other sensitive applications.