Aqueous compositions and inkjet receiving media
An aqueous composition can be used for pre-treating a substrate prior to inkjet printing to provide a white opaque background for inkjet-printed images. This aqueous composition includes: (a) one or more water-soluble salts of a multivalent metal cation at 5-30 weight %; (b) a nonionic or cationic water-soluble or water-dispersible polymeric binder material at 5-30 weight %; and (c) surface-treated visible light-scattering particles having a D 50 (median) particle size of at least 0.04 μm and up to and including 2 μm in an amount of 5-60 weight % based on the total aqueous composition weight. The pre-treated substrate is useful as an inkjet receiving medium that can be readily inkjet-printed particularly with anionically-stabilized aqueous pigment-based inks.
1 . An inkjet receiving medium for use in high-speed inkjet printing processes when using aqueous pigment-based inks containing anionically-stabilized pigments, the inkjet receiving medium comprising:
a substrate that is a transparent polyethylene terephthalate film, a transparent polypropylene film, or a metallized polyethylene terephthalate film, and
a topcoat composition disposed on a surface thereof, wherein the disposed topcoat composition has a dry solids coating weight of at least 0.1 g/m 2 and up to and including 2 g/m 2 , and the inkjet receiving medium has an opacity of at least 50% and a colorimetry defined by an a* value of at least −3 and up to and including +3 and a b* value of at least −3 and up to and including +3,
wherein the disposed topcoat composition comprises the following (a), (b), and (c) components:
(a) one or more water-soluble salts of a calcium or magnesium metal cation present in an amount of at least 4 weight % and up to and including 13 weight %;
(b) one or more nonionic or cationic water-soluble or water-dispersible polymeric binder materials selected from a poly(vinyl alcohol), a polyethylene imine, a polyvinyl amine, and a polyurethane, or a mixture thereof, that are present in an amount of at least 10 weight % and up to and including 30 weight %; and
(c) visible light-scattering titanium dioxide or zinc oxide particles that have been surface-treated using a (f) dispersing aid aids so that the (c) surface-treated visible-light scattering titanium dioxide or zinc oxide particles have a stable zeta potential of greater than +10 millivolts (mV), which (c) surface-treated visible light-scattering titanium dioxide or zinc oxide particles exhibit a D 50 particle size of at least 0.04 μm and up to and including 2 μm, as measured by a particle analyzer providing a volume-weighted particle size distribution and are present in an amount of at least 15 weight % and up to and including 75 weight %,
wherein the (f) dispersing aid is a protonated polyvinyl amine and is present in the topcoat composition in an amount of at least 0.5 weight % and up to and including 61.9 weight %, based on the total weight of the (c) surface-treated visible light-scattering titanium dioxide or zinc oxide particles, and
wherein the amounts of the (a), (b), and (c) components are based on the total weight of the topcoat composition.
2 . The inkjet receiving medium of claim 1 , wherein the topcoat composition further comprises:
(d) particles different from the (c) component, wherein the (d) particles have a Rockwell Hardness of less than or equal to R90, and which are present in an amount of at least 0.06 weight % and up to and including 10 weight %, based on the total weight of the topcoat composition.
3 . The inkjet receiving medium of claim 1 , wherein the topcoat composition further comprises:
(e) a crosslinkable polymeric material that is different from all of the (a), (b), and (c) components, and wherein the (e) crosslinkable polymeric material is present in the topcoat composition in an amount of at least 0.1 weight % and up to and including 30 weight %, based on the total weight of the topcoat composition.
4 . The inkjet receiving medium of claim 1 , wherein the (c) surface-treated visible light-scattering particles comprise titanium dioxide.
5 . The inkjet receiving medium of claim 1 , wherein the topcoat composition has a dry solids coating weight of at least 0.2 g/m 2 and up to and including 1 g/m 2 .
6 . A method for providing the inkjet receiving medium of claim 1 , the method comprising, in order:
A) providing a substrate that is a transparent polyester film, a metallized polymeric film, or a transparent polypropylene polymeric film; and
B) disposing an aqueous composition onto at least one surface of the substrate to provide a topcoat composition on the at least one surface,
which aqueous composition has at least 2% solids and up to and including 90% solids, and comprises the following (a), (b), and (c) components:
(a) one or more water-soluble salts of a calcium or magnesium metal cation, wherein the (a) one or more water-soluble salts are present in an amount of at least 1 weight % and up to and including 8 weight %;
(b) one or more nonionic or cationic water-soluble or water-dispersible polymeric binder materials selected from a poly(vinyl alcohol), a polyethylene imine, a polyvinyl amine, and a polyurethane, or a mixture thereof, in an amount of at least 0.5 weight % and up to and including 30 weight %; and
(c) visible light-scattering titanium dioxide or zinc oxide particles that have been surface-treated using a protonated polyvinyl amine as a (f) dispersing aid so that the (c) surface-treated visible light-scattering titanium dioxide or zinc oxide particles have a stable zeta potential of greater than +10 millivolts, wherein the (c) surface-treated visible light-scattering particles exhibit a D50 particle size of at least 0.04 μm and up to and including 2 μm, as measured by a particle analyzer providing a volume-weighted particle size distribution, and are present in an amount of at least 5 weight % and up to and including 60 weight %,
wherein the (f) dispersing aid is different from the (a) one or more water-soluble salts of a multivalent metal cation, and is present in the aqueous composition in an amount of at least 0.2 weight % and up to and including 61.9 weight %, based on the total weight of the (c) surface-treated visible light-scattering particles, and
wherein the amounts of the (a), (b), and (c) components are based on the total weight of the aqueous composition,
to provide the inkjet receiving medium having a topcoat composition on the at least one substrate surface, the topcoat composition having a dry solids coating weight of at least 0.1 g/m 2 and up to and including 2 g/m 2 , and the inkjet receiving medium having an opacity of at least 50% and a colorimetry defined by an a* value of at least −3 and up to and including +3 and a b* value of at least −3 and up to and including +3.
7 . The method of claim 6 , comprising disposing the aqueous composition on the at least one substrate surface in-line following preparation of the substrate.
8 . An inkjet receiving medium for use in high-speed inkjet printing processes when using aqueous pigment-based inks containing anionically-stabilized pigments, the inkjet receiving medium comprising:
a substrate that is a transparent polyethylene terephthalate film, a transparent polypropylene film, or a metallized polyethylene terephthalate film, and
an opaque topcoat composition disposed on a surface thereof, wherein the disposed topcoat composition has a dry solids coating weight of at least 0.1 g/m 2 and up to and including 1 g/m 2 , and the inkjet receiving medium has an opacity of at least 50% and a colorimetry defined by an a* value of at least −3 and up to and including +3 and a b* value of at least −3 and up to and including +3,
wherein the disposed topcoat composition comprises the following (a), (b), and (c) components:
(a) one or more water-soluble salts of a magnesium metal cation present in an amount of at least 4 weight % and up to and including 13 weight %;
(b) one or more nonionic or cationic water-soluble or water-dispersible polymeric binder materials selected from a poly(vinyl alcohol), a polyvinyl amine, or a mixture thereof, that are present in an amount of at least 10 weight % and up to and including 30 weight %; and
(c) visible light-scattering titanium dioxide particles that have been surface-treated using a (f) dispersing aid so that the (c) surface-treated visible-light scattering titanium dioxide particles have a stable zeta potential of greater than +10 millivolts (mV), which (c) surface-treated visible light-scattering titanium dioxide particles exhibit a D 50 particle size of at least 0.04 μm and up to and including 2 μm, as measured by a particle analyzer providing a volume-weighted particle size distribution and are present in an amount of at least 15 weight % and up to and including 75 weight %,
wherein the (f) dispersing aid is a protonated polyvinyl amine and is present in the topcoat composition in an amount of at least 0.5 weight % and up to and including 61.9 weight %, based on the total weight of the (c) surface-treated visible light-scattering titanium dioxide particles, and
wherein the amounts of the (a), (b), and (c) components are based on the total weight of the topcoat composition.
9 . The inkjet receiving medium of claim 8 , wherein the opaque topcoat composition disposed on the surface of the substrate only in a specific area thereof to form a pattern.