The present invention relates to the field of security inks suitable for printing machine readable security features on substrate, security documents or articles as well as machine readable security feature made from said security inks, and security documents comprising a machine readable security feature made from said security inks. In particular, the invention provides security inks comprising one or more IR absorbing materials wherein said security ink allows the production of a machine readable security feature having the following optical properties: a lightness L* equal to or higher than about 80, a chroma C* smaller than or equal to about 15 and a reflectance at 900 nm smaller than or equal to about 60%.

A rosin-modified resin having a structural unit (ab) derived from a compound obtained by addition of an α,β-unsaturated carboxylic acid or acid anhydride thereof (B) to a conjugated rosin acid (A), a structural unit (c) derived from an organic monobasic acid (C) excluding the conjugated rosin acid (A), a structural unit (d) derived from an aliphatic polybasic acid anhydride (D), and a structural unit (e) derived from a polyol (E), wherein the weight ratio between the structural unit (ab) and the structural unit (c) is within a range from 100:80 to 100:350.

A rosin-modified resin having a structural unit (ab) derived from a compound obtained by addition of an α,β-unsaturated carboxylic acid or acid anhydride thereof (B) to a conjugated rosin acid (A), a structural unit (c) derived from an organic monobasic acid (C) excluding the conjugated rosin acid (A), a structural unit (d) derived from an aliphatic polybasic acid anhydride (D), and a structural unit (e) derived from a polyol (E), wherein the weight ratio between the structural unit (ab) and the structural unit (c) is within a range from 100:80 to 100:350.

Provided is a radiation-curable ink that has low odor, excellent curability, and can provide a printed matter that has excellent hardness and toughness. The radiation-curable ink includes the monofunctional polymerizable compound (β) having a heterocyclic structure in which a hetero atom is an oxygen atom, and a multifunctional polymerizable compound (γ) having an alicyclic structure. It is preferable that the radiation-curable ink further include a multifunctional polymerizable compound (Z) not having a bicyclo structure or a higher cyclic structure. It is preferable that the monofunctional polymerizable compound be a monofunctional (meth)acrylate and the multifunctional polymerizable compound be a multifunctional (meth)acrylate.

Provided is a radiation-curable ink that has low odor, excellent curability, and can provide a printed matter that has excellent hardness and toughness. The radiation-curable ink includes the monofunctional polymerizable compound (β) having a heterocyclic structure in which a hetero atom is an oxygen atom, and a multifunctional polymerizable compound (γ) having an alicyclic structure. It is preferable that the radiation-curable ink further include a multifunctional polymerizable compound (Z) not having a bicyclo structure or a higher cyclic structure. It is preferable that the monofunctional polymerizable compound be a monofunctional (meth)acrylate and the multifunctional polymerizable compound be a multifunctional (meth)acrylate.

A nonwoven substrate has a first surface and a second surface opposite the first surface. The first surface may include one or more printed portions, wherein at least one printed portion has a curable ink. Said printed portion may exhibit a Crosslinking Index of about 330 or less as determined by the Crosslinking Index Test Method herein and an IAR (Mineral Oil) of 1.30 or greater as determined by the IAR Test Method herein.

A nonwoven substrate has a first surface and a second surface opposite the first surface. The first surface may include one or more printed portions, wherein at least one printed portion has a curable ink. Said printed portion may exhibit a Crosslinking Index of about 330 or less as determined by the Crosslinking Index Test Method herein and an IAR (Mineral Oil) of 1.30 or greater as determined by the IAR Test Method herein.

A method of manufacturing a Printed Circuit Board (PCB) wherein an inkjet printing step is used, characterized in that in the inkjet printing step a radiation curable inkjet ink comprising an adhesion promoter having a chemical structure according to Formula I is jetted and cured on a substrate, wherein X is selected from the group consisting of O and NR.sub.3, L.sub.1 and L.sub.2 independently represent a divalent linking group comprising from 2 to 20 carbon atoms, R.sub.1 is selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group and a substituted or unsubstituted aryl group, R.sub.2 is selected from the group consisting of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted aralkyl group and a substituted or unsubstituted (hetero)aryl group, R3 is selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted aralkyl group and a substituted or unsubstituted (hetero)aryl group, n represents an integer from 0 to 4, any of L.sub.1, L.sub.2 and R.sub.2 may represent the necessary atoms to form a 5 to 8 membered ring. ##STR00001##

A method of manufacturing a Printed Circuit Board (PCB) wherein an inkjet printing step is used, characterized in that in the inkjet printing step a radiation curable inkjet ink comprising an adhesion promoter having a chemical structure according to Formula I is jetted and cured on a substrate, wherein X is selected from the group consisting of O and NR.sub.3, L.sub.1 and L.sub.2 independently represent a divalent linking group comprising from 2 to 20 carbon atoms, R.sub.1 is selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group and a substituted or unsubstituted aryl group, R.sub.2 is selected from the group consisting of a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted aralkyl group and a substituted or unsubstituted (hetero)aryl group, R3 is selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted aralkyl group and a substituted or unsubstituted (hetero)aryl group, n represents an integer from 0 to 4, any of L.sub.1, L.sub.2 and R.sub.2 may represent the necessary atoms to form a 5 to 8 membered ring. ##STR00001##

Provided are a method for producing a printed matter and a printing machine which suppress the decrease of transferability and improve adhesiveness between ink and a film substrate when ink is printed on the film substrate. The method for producing a printed matter of the present invention is a method for producing a printed matter by printing ink on a film, which uses a film having a nitrogen element concentration of 0.5 to 10.0 atom % in the film surface, and includes irradiating with an active energy ray after printing.