Onium borates/borates of organometallic complexes and cationic initiation of polymerization therewith

A polymerizable or crosslinkable composition comprising:

• (a) at least one polymerizable or crosslinkable oligomer;
• and
• (b) at least one initiator salt selected from onium borates and borates of an organometallic complex, the cationic moiety of which comprising:
• (1) an onium cation having the formula (I):
• [(R.sup.1).sub.n -A-(R.sup.2).sub.m ].sup.+ (I)
• in which A is an element of Groups 15 to 17 of the Periodic Table;
• R.sup.1 is a C.sub.6 -C.sub.20 heterocyclic or carbocyclic aryl radical;
• R.sup.2 is R.sup.1 or a linear or branched C.sub.1 -C.sub.30 alkenyl or alkyl radical, said radicals R.sup.1 or R.sup.2 optionally being substituted by at least one C.sub.1 -C.sub.25 alkoxy, C.sub.1 -C.sub.25 alkyl, nitro, chloro, bromo, cyano, carboxyl, ester or mercapto substituent;
• n is an integer ranging from 1 to v+1, with v being the valence of A;
• and m is an integer ranging from 0 to v-1, with the proviso that n+m=v+1;
• (2) an oxoisothiochromanium cation;
• or
• (3) an organometallic cation having the formula (II):
• (L.sup.1 L.sup.2 L.sup.3 M).sup.q+ (II)
• in which M is a metal of Groups 4 to 10 of the Periodic Table;
• L.sup.1 is a ligand associated with the metal M via .pi. electrons and is an .eta..sup.3 -allyl, .eta..sup.5 -cyclopentadienyl or .eta..sup.7 -cycloheptatrienyl ligand or an .eta..sup.6 -aromatic compound selected from among the optionally substituted .eta..sup.6 -benzene ligands and compounds having from 2 to 4 condensed ring members, each ring member contributing to the valence shell of the metal M via 3 to 8 .pi. electrons;
• L.sup.2 is a ligand associated with the metal M via .pi. electrons and is an .eta..sup.7 -cycloheptatrienyl ligand or an .eta..sup.6 -aromatic compound selected from among the optionally substituted .eta..sup.6 -benzene ligands and compounds having from 2 to 4 condensed ring members, each ring member contributing to the valence shell of the metal M via 6 or 7 .pi. electrons;
• and L.sup.3 represents from 0 to 3 identical or different ligands associated with the metal M via .sigma. electrons and is CO or NO.sub.2.sup.+ ligands, the total electron charge q of the complex to which L.sup.1, L.sup.2 and L.sup.3 contribute and the ionic charge of the metal M being positive and equal to 1 or 2;
• and
• the anionic borate moiety of which having the formula:
• [BX.sub.a R.sub.b ].sup.-
• in which a and b are integers ranging from 0 to 4 and a+b=4;
• the symbols X are each a halogen atom when a ranges up to 3 and an OH functional group when a ranges up to 2;
• and the symbols R, which may be identical or different, are each a phenyl radical substituted by at least one electron-withdrawing substituent or by at least two halogen atoms, or an aryl radical containing at least two aromatic ring members, or such aryl radical bearing at least one electron-withdrawing substituent.

A composition which is polymerizable or crosslinkable by photochemical activation or activation under an electron beam, said composition comprising:

• (a) at least one oligomer bearing functional group(s);
• and
• (b) at least one initiator salt selected from onium borates and borates of an organometallic complex, the cationic moiety of which comprising:
• (1) an onium cation having the formula (I):
• [(R.sup.1).sub.n -A-(R.sup.2).sub.m ].sup.+ (I)
• in which A is an element of Groups 15 to 17 of the Periodic Table;
• R.sup.1 is a C.sub.6 -C.sub.20 heterocyclic or carbocyclic aryl radical;
• R.sup.2 is R.sup.1 or a linear or branched C.sub.1 -C.sub.30 alkenyl or alkyl radical, said radicals R.sup.1 or R.sup.2 optionally being substituted by at least one C.sub.1 -C.sub.25 alkoxy, C.sub.1 -C.sub.25 alkyl, nitro, chloro, bromo, cyano, carboxyl, ester or mercapto substituent;
• n is an integer ranging from 1 to v+1, with v being the valence of A;
• and m is an integer ranging from 0 to v-1, with the proviso that n+m=v+1;
• (2) an oxoisothiochromanium cation;
• or
• (3) an organometallic cation having the formula (II):
• (L.sup.1 L.sup.2 L.sup.3 M).sup.q+ (II)
• in which M is a metal of Groups 4 to 10 of the Periodic Table;
• L.sup.1 is a ligand associated with the metal M via .pi. electrons and is an .eta..sup.3 -allyl, .eta..sup.5 -cyclopentadienyl or .eta..sup.7 -cycloheptatrienyl ligand or an .eta..sup.6 -aromatic compound selected from among the optionally substituted .eta..sup.6 -benzene ligands and compounds having from 2 to 4 condensed ring members, each ring member contributing to the valence shell of the metal M via 3 to 8 .pi. electrons;
• L.sup.2 is a ligand associated with the metal M via .pi. electrons and is an .eta..sup.7 -cycloheptatrienyl ligand or an .eta..sup.6 -aromatic compound selected from among the optionally substituted .eta..sup.6 -benzene ligands and compounds having from 2 to 4 condensed ring members, each ring member contributing to the valence shell of the metal M via 6 or 7 .pi. electrons;
• and L.sup.3 represents from 0 to 3 identical or different ligands associated with the metal M via .sigma. electrons and is CO or NO.sub.2.sup.+ ligands, the total electron charge q of the complex to which L.sup.1, L.sup.2 and L.sup.3 contribute and the ionic charge of the metal M being positive and equal to 1 or 2;
• and
• the anionic borate moiety of which having the formula:
• [BX.sub.a R.sub.b ].sup.-
• in which a and b are integers ranging from 0 to 4 and a+b=4;
• the symbols X are each a halogen atom when a ranges up to 3 and an OH functional group when a ranges up to 2;
• and the symbols R, which may be identical or different, are each a phenyl radical substituted by at least one electron-withdrawing substituent or by at least two halogen atoms, or an aryl radical containing at least two aromatic ring members, or such aryl radical bearing at least one electron-withdrawing substituent.