Water-soluble coating agents bearing initiator groups

A coating system comprising:

• a) a coating agent comprising two or more photoreactive species and one or more negatively charged groups, the coating agent selected from:
• i) a conjugated cyclic diketone having attached thereto, either directly or indirectly, one or more substituents comprising negatively charged groups, and wherein each ketone group of the diketone is able to serve as a photoreactive moiety capable of being activated in order to provide a free radical;
• and
• ii) a nonpolymeric core molecule having attached thereto, either directly or indirectly, one or more substituents comprising negatively charged groups, and two or more photoreactive species, wherein the photoreactive species are provided as discrete photoreactive groups;
• wherein the photoreactive species include at least one first photoreactive species able when activated in the presence of the support surface, to attach the coating agent to the surface, and at least one second photoreactive species able when activated in the presence of free radical polymerizable groups, to initiate polymerization of those groups, the second photoreactive species being able in the absence of such free radical polymerizable groups, to revert to a latent reactive state;
• and
• b) a plurality of molecules bearing free radical polymerizable groups.

A coating agent comprising a compound of the formula:

• wherein
• X1 comprises a first photoreactive group;
• X2 comprises a second photoreactive group;
• Y comprises a nonpolymeric core molecule;
• and
• Z comprises at least one charged group.

A method of coating a support surface with a coating agent in order to provide latent reactive groups, the method comprising:

• a) providing a support surface;
• b) applying to the support surface a coating agent comprising two or more photoreactive species and one or more negatively charged groups, the coating agent selected from:
• i) a conjugated cyclic diketone having attached thereto, either directly or indirectly, one or more substituents comprising negatively charged groups, and wherein each ketone group of the diketone is able to serve as a photoreactive moiety capable of being activated in order to provide a free radical;
• and
• ii) a nonpolymeric core molecule having attached thereto, either directly or indirectly, one or more substituents comprising negatively charged groups, and two or more photoreactive species, wherein the photoreactive species are provided as discrete photoreactive groups;
• wherein the photoreactive species include at least one first photoreactive species adapted, when activated in the presence of the support surface, to attach the coating agent to the surface, and at least one second photoreactive species able when activated in the presence of free radical polymerizable groups, to initiate polymerization of those groups, the second photoreactive species being able in the absence of such free radical polymerizable groups, to revert to a latent reactive state;
• and
• c) illuminating the agent upon the support surface under conditions suitable to photochemically attach the coating agent to the surface by means of the first photoreactive species, and to allow the second photoreactive species to remain unbound to the support surface and to revert to their latent reactive state.

A support surface bearing a coating comprising a polymer layer attached to the surface by a coating agent, the coating agent comprising the residues of two or more photoreactive species and one or more negatively charged groups, the coating agent selected from:

• i) a conjugated cyclic diketone having attached thereto, either directly or indirectly, one or more substituents comprising negatively charged groups, and wherein each ketone group of the diketone was able to serve as a photoreactive moiety capable of being activated in order to provide a free radical;
• and
• ii) a nonpolymeric core molecule having attached thereto, either directly or indirectly, one or more subsituents comprising negatively charged groups, and the residues of two or more photoreactives species, wherein the photoreactive species were provided as discrete photoreactive groups;
• wherein the photoreactive species included at least one first photoreactive species able when activaed in the presence of the support surface, to attach the coating agent to the surface, and a least one second photoreactive species able when activated in the presence of free radical polymerizable groups, to initate polymerization of those groups, the second photoreactive species being able in the absence of such free radical polymerizable groups, to revert to a latent reactive state.