An active energy ray-curable ink composition for offset printing that contains a compound having an ethylenically unsaturated bond and a photopolymerization initiator is combined with: a rosin-modified alkyd resin being a condensation polymer of a polyhydric alcohol with an acid component containing a resin acid, a fatty acid, and a polybasic acid, and having a predetermined solubility parameter (SP value) and a predetermined acid value; and a specific liquid component having a predetermined SP value.

A stealth white ink contains a red coloring material that emits visible light at exposure to ultraviolet radiation, a green coloring material that emits visible light at exposure to ultraviolet radiation, and a blue coloring material that emits visible light at exposure to ultraviolet radiation, wherein a dry film of the stealth white ink has an a* value of from −2.0 to 2.0 and a b* of from −10.0 to 0 at exposure to ultraviolet radiation having a wavelength of 370 nm according to CIE 1976 L*a*b* colorimetric system.

A stealth white ink contains a red coloring material that emits visible light at exposure to ultraviolet radiation, a green coloring material that emits visible light at exposure to ultraviolet radiation, and a blue coloring material that emits visible light at exposure to ultraviolet radiation, wherein a dry film of the stealth white ink has an a* value of from −2.0 to 2.0 and a b* of from −10.0 to 0 at exposure to ultraviolet radiation having a wavelength of 370 nm according to CIE 1976 L*a*b* colorimetric system.

Inorganic particulate compositions containing inorganic particles associated with a copolymer of a hydrophilic monomer and a hydrophobic monomer associated with the inorganic particles are provided. The particulate composition satisfies at least one of the following properties: a BET surface area of the inorganic particles is greater than 8 m.sup.2/g, a Hegman value of the inorganic particles is 75 microns or less, and a rate of water loss from the composition upon drying from a moisture level greater than 2% wt % is at least 30% greater than a composition having a corresponding content of a polyacrylate polymer associated with the particles. A method to prepare the composition and formulations for inks, paints, coatings and filled polymeric articles containing the inorganic particulate composition are also provided.

Inorganic particulate compositions containing inorganic particles associated with a copolymer of a hydrophilic monomer and a hydrophobic monomer associated with the inorganic particles are provided. The particulate composition satisfies at least one of the following properties: a BET surface area of the inorganic particles is greater than 8 m.sup.2/g, a Hegman value of the inorganic particles is 75 microns or less, and a rate of water loss from the composition upon drying from a moisture level greater than 2% wt % is at least 30% greater than a composition having a corresponding content of a polyacrylate polymer associated with the particles. A method to prepare the composition and formulations for inks, paints, coatings and filled polymeric articles containing the inorganic particulate composition are also provided.

A plasma-curable ink composition for offset printing having high reactivity with plasma and capable of being hardened into a sufficiently dried state even in the use of plasma generated by a remote-type plasma generator, and a method for producing printed matter and a method for printing information using the same. The plasma-curable ink composition for offset printing comprises a pigment, a binder resin, and at least one specific ingredient selected from the group consisting of castor oil, polymerized oil, and alkyd resins having an acid value of 10 mg KOH/g or more.

Provided are a curing accelerator for an oxidative polymerization type unsaturated resin having a high curing accelerating ability, and a printing ink and a coating material. Specifically, there are provided a curing accelerator for an oxidative polymerization type unsaturated resin, containing a metal complex () having an anion compound () represented by the following structural formula (1-1) or (1-2) as a ligand: ##STR00001##
wherein R.sup.1 is any one of a hydroxyl group, an amino group, a nitro group, a nitroso group, a sulfo group, a halogen atom, a hydrocarbon group which may have a substituent, a hydrocarbon oxy group which may have a substituent, and a hydrocarbon oxycarbonyl group which may have a substituent, m is 0 or an integer of 1 to 3, n is 0 or an integer of 1 to 6, and X is any one of a carboxylate group, a hydrogen atom, and the R.sup.1 group.

Inorganic particulate compositions containing inorganic particles associated with a copolymer of a hydrophilic monomer and a hydrophobic monomer associated with the inorganic particles are provided. The particulate composition satisfies at least one of the following properties: a BET surface area of the inorganic particles is greater than 8 m.sup.2/g, a Hegman value of the inorganic particles is 75 microns or less, and a rate of water loss from the composition upon drying from a moisture level greater than 2% wt % is at least 30% greater than a composition having a corresponding content of a polyacrylate polymer associated with the particles. A method to prepare the composition and formulations for inks, paints, coatings and filled polymeric articles containing the inorganic particulate composition are also provided.

Inorganic particulate compositions containing inorganic particles associated with a copolymer of a hydrophilic monomer and a hydrophobic monomer associated with the inorganic particles are provided. The particulate composition satisfies at least one of the following properties: a BET surface area of the inorganic particles is greater than 8 m.sup.2/g, a Hegman value of the inorganic particles is 75 microns or less, and a rate of water loss from the composition upon drying from a moisture level greater than 2% wt % is at least 30% greater than a composition having a corresponding content of a polyacrylate polymer associated with the particles. A method to prepare the composition and formulations for inks, paints, coatings and filled polymeric articles containing the inorganic particulate composition are also provided.

To provide a curing accelerator for an oxidatively polymerizable unsaturated resin which can decrease the amount of cobalt metal soap used and has curing performance equal to or higher than excellent curing performance of the cobalt metal soap, and a printing ink and a coating material using the same. A curing accelerator for an oxidatively polymerizable unsaturated resin including a manganese or cobalt complex () containing quinolinol compound ions represented by Structural Formula (1) as a ligand, and a printing ink and a coating material including the curing accelerator. ##STR00001##
In the formula, R.sup.1 is any of a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a hydroxyl group, an amino group, a nitro group, a nitroso group, a sulfo group, and a halogen atom, and n is an integer of 1 to 6.