The invention relates to compositions, having a) 1.00 to 65.00% by weight of at least one compound of formula (I), wherein R.sup.1, R.sup.2 are each independently H, C.sub.1-C.sub.6-alkyl, or C.sub.1-C.sub.6-alkoxy-C.sub.1-C.sub.6-alkyl; R.sup.3, R.sup.4, R.sup.5 are each independently H, C.sub.1-C.sub.6-alkyl, or C.sub.1-C.sub.6-alkoxy-C.sub.1-C.sub.6-alkyl; R.sup.6 is H or C.sub.1-C.sub.6-alkyl; k is 1, 2, 3, 4 or 5, as component A; b) 1.00 to 60.00% by weight of at least one monomer having two (meth)acrylate groups and 1 having a molecular weight Mw of no more than 500 Dalton, as component B; c) 0 to 25% by weight of at least one monomer having at least three (meth)acrylate groups and having a molecular weight Mw of no more than 600 Dalton, as component C; and d) 1.00 to 30.00% by weight of at least one polymer having at least two (meth)acrylate groups and having a molecular weight Mw of at least 700 Dalton, as component D; with the proviso that the amount of components A+B is at least 50% by weight, as well as the use of these compositions as printing inks, in particular inkjet printing inks. ##STR00001##

In a three-dimensional printing method example, a pre-treatment coating is formed on a part precursor by applying and drying, alternatingly: a polycation solution including a chloride ion and a polyanion solution including a sodium ion to form at least two layers. An ink is selectively deposited on the pre-treatment coating.

An anti-counterfeit ink composition, an anti-counterfeit ink, and an anti-counterfeit printed matter that transmits a visible light region, having absorption in an infrared region, and capable of judging authenticity of the printed matter, and there is provided an anti-counterfeit ink composition, an anti-counterfeit ink, an anti-counterfeit printed matter, and a method for producing the anti-counterfeit ink composition, wherein a value of an XRD peak top intensity ratio of the composite tungsten oxide ultrafine particles is 0.13 or more when a value of the XRD peak intensity is set to 1, with plane of a silicon powder standard sample (640c produced by NIST) as a reference.

An anti-counterfeit ink composition, an anti-counterfeit ink, and an anti-counterfeit printed matter that transmits a visible light region, having absorption in an infrared region, and capable of judging authenticity of the printed matter, and there is provided an anti-counterfeit ink composition, an anti-counterfeit ink, an anti-counterfeit printed matter, and a method for producing the anti-counterfeit ink composition, wherein a value of an XRD peak top intensity ratio of the composite tungsten oxide ultrafine particles is 0.13 or more when a value of the XRD peak intensity is set to 1, with plane of a silicon powder standard sample (640c produced by NIST) as a reference.

A UV-curable and recyclable thermoset shape memory polymer is provided. The polymer includes a vitrimer-based monomer and a photoinitiator. The vitrimer-based monomer includes a first unit rendering a high chain stiffness upon polymerization of the monomer, and a second photopolymerizable unit for photopolymerization of the monomer under a UV irradiation. The polymer has high strength, high stiffness, high recovery stress, high energy storage, reasonable recycling efficiency, and is printable using SLA with high resolution.

A fluorene-based photoinitiator, a preparation method thereof, a photocurable composition having the same, and use thereof in the field of photocuring are disclosed. In some embodiments, the fluorene-based photoinitiator has a structure represented by Formula I, wherein X is -A-(X).sub.n, wherein A is selected from a heteroatom which is selected from O, N, or S, X is selected from a C.sub.1-C.sub.20 linear alkyl group, a C.sub.1-C.sub.20 branched alkyl group, a C.sub.3-C.sub.8 cycloalkyl group, a C.sub.1-C.sub.10 alkyl group substituted with a C.sub.3-C.sub.8 cycloalkyl group or one or more of carbon atoms in X are substituted with a heteroatom, and n is 1 or 2; and R.sub.4 is a hydroxy group or a N-morpholinyl group. In some embodiments, the fluorene-based photoinitiator comprises a structure represented by Formula II.

A fluorene-based photoinitiator, a preparation method thereof, a photocurable composition having the same, and use thereof in the field of photocuring are disclosed. In some embodiments, the fluorene-based photoinitiator has a structure represented by Formula I, wherein X is -A-(X).sub.n, wherein A is selected from a heteroatom which is selected from O, N, or S, X is selected from a C.sub.1-C.sub.20 linear alkyl group, a C.sub.1-C.sub.20 branched alkyl group, a C.sub.3-C.sub.8 cycloalkyl group, a C.sub.1-C.sub.10 alkyl group substituted with a C.sub.3-C.sub.8 cycloalkyl group or one or more of carbon atoms in X are substituted with a heteroatom, and n is 1 or 2; and R.sub.4 is a hydroxy group or a N-morpholinyl group. In some embodiments, the fluorene-based photoinitiator comprises a structure represented by Formula II.

The present invention provides a UV-Vis radiation curable security ink for producing a security feature for securing value documents, wherein said security feature exhibits a blue color upon viewing in transmitted light and a metallic yellow color upon viewing in incident light. The UV-Vis radiation curable security ink comprises a cationically curable or a hybrid curable ink vehicle, and silver nanoplatelets bearing a surface stabilizing agent of general formula (I)

##STR00001## wherein the residue R.sup.A is a C.sub.2-C.sub.4alkyl group substituted with a hydroxy group; the residue R.sup.B is selected from a C.sub.1-C.sub.4 alkyl group, and a C.sub.2-C.sub.4alkyl group substituted with a hydroxy group; and Cat.sup.+ is a cation selected from the group consisting of Na.sup.+, K.sup.+, Cs.sup.+ and Rb.sup.+.

The present invention provides a UV-Vis radiation curable security ink for producing a security feature for securing value documents, wherein said security feature exhibits a blue color upon viewing in transmitted light and a metallic yellow color upon viewing in incident light. The UV-Vis radiation curable security ink comprises a cationically curable or a hybrid curable ink vehicle, and silver nanoplatelets bearing a surface stabilizing agent of general formula (I)

##STR00001## wherein the residue R.sup.A is a C.sub.2-C.sub.4alkyl group substituted with a hydroxy group; the residue R.sup.B is selected from a C.sub.1-C.sub.4 alkyl group, and a C.sub.2-C.sub.4alkyl group substituted with a hydroxy group; and Cat.sup.+ is a cation selected from the group consisting of Na.sup.+, K.sup.+, Cs.sup.+ and Rb.sup.+.

A radiation curable ink jet composition contains: a dispersant; a polymerizable compound; and a hindered amine compound represented by the following general formula (1) or (2), the radiation curable ink jet composition has a viscosity of 50 mPa.Math.s or less at 25 C., and the dispersant has an acid value of 30 mgKOH/g or more,

##STR00001##

In the formula (1), R.sup.1 represents H, O, or R.sup.2CO, and R.sup.2 represents an alkyl group having 1 to 6 carbon atoms or a substituted or unsubstituted aromatic ring,

##STR00002##

In the formula (2), R.sup.3 represents OCOR.sup.4COO, and R.sup.4 represents an alkyl group having 1 to 12 carbon atoms.