DIGITAL SOL-GEL MULTIFUNCTIONAL WATER BASED INKS

Abstract

The invention generally concerns a sol-gel digital inkjet printing process for forming a pattern on a surface region, the process comprising applying a formulation on the surface region, the formulation comprising a silanol functionalized polymer and a polymer-free pigment dispersion, said applying being under conditions permitting formation of particles formed of the silanol functionalized polymer, and curing said particles to form a continuous pattern

Claims

1-63. (canceled)

64. A sol-gel digital inkjet printing process for forming a dry pre-treatment pattern on a surface region, the process comprising (1) applying a formulation on the surface region, the formulation being an ink set formulation comprising (a) at least one low-temperature curing self-crosslinking polymer selected from silanol functionalized polymers, and (b) a catalyst in the form of an anti-bleeding polymer in combination with at least one salt; wherein said applying being under conditions permitting formation of particles formed of the silanol functionalized polymer, and (2) curing said particles to form a continuous pattern.

65. The sol-gel digital inkjet printing process according to claim 64, wherein the at least one low-temperature curing self-crosslinking polymer selected from silanol functionalized polymer is fully silanol functionalize polymer.

66. The process according to claim 64, for enhancement of a printed pattern, or for providing a 3D enhanced pattern.

67. The process according to claim 64, wherein the silanol functionalized polymer is selected to undergo curing via low temperature crosslinking.

68. The process according to claim 67, wherein the low temperature being a temperature between room temperature and 110° C.

69. The process according to claim 64, wherein the silanol functionalized polymer is selected amongst acidic pH-reactive polymers and basic pH-reactive polymers.

70. The process according to claim 64, wherein the silanol functionalized polymer is selected amongst polymers or pre-polymers having a Tg value in the range of −70° C. to 400° C., when measured on the dry printed pattern.

71. The process according to claim 64, wherein the silanol functionalized polymer is selected amongst ether-polyols, ester-polyols and carbonate-polyols, poly ethers, water based acrylics, epoxy polymers, phenolic polymers, polyamide, polyamines, micronized polyethylene waxes and polyurethane.

72. The process according to claim 64, wherein the silanol functionalized polymer is a polyurethane polymer or an acrylic polymer.

73. The process according to claim 64, wherein the ink formulation is formulated as an aqueous formulation comprising water and/or a water-miscible organic solvent.

74. A colored inkjet ink formulation comprising a pigment, a fully silanol functionalized polymer, and a carrier, wherein the fully silanol functionalized polymer undergoes crosslinking upon contacting with an anti-bleeding polymer in combination with at least one salt.

75. The ink according to claim 74, wherein upon contacting the fully silanol functionalized polymer with the anti-bleeding polymer and at least one salt, the viscosity increases to afford 3-dimensional gelation.

76. The ink according to claim 74, wherein the fully silanol functionalized polymer is a fully silanol functionalized polyurethane, wherein the number of hydroxyl groups in the silanol group is at least one.

77. A method of inkjet printing a color pattern on a substrate, the method comprises: patterning by inkjet printing an amount of a formulation according to claim 74 onto a dry surface region of the substrate having been treated with a catalyst formulation comprising an antibleeding polymer and at least one salt; and inducing crosslinking of the fully silanol functionalized polymer in the formulation to form a colored pattern on the substrate.

78. The method according to claim 77, wherein the substrate is of a material selected from leather, polymeric surfaces, paper or paper products, natural or synthetic fibers, flexible packaging materials, plastic or synthetic materials, textiles made from natural or synthetic materials, glass, and metallic materials.

79. The method according to claim 77, wherein the anti-bleeding polymer is a polyurethane, a cellulosic material, or a polyacrylate.

80. The method according to claim 77, wherein at least one salt is a sodium salt, an aluminum salt, a copper salt, a zinc salt, a cobalt salt, a nickel salt, a magnesium salt, an ammonium salt or a calcium salt.

81. The process according to claim 64, wherein the anti-bleeding polymer is a polyurethane, a cellulosic material or a polyacrylate.

82. The process according to claim 64, wherein the at least one salt is a sodium salt, an aluminum salt, a copper salt, a zinc salt, a cobalt salt, a nickel salt, a magnesium salt, an ammonium salt or a calcium salt.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0120] In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

[0121] FIG. 1 provides a pictorial description of uses and applications of ink formulations according to the invention.

[0122] FIG. 2 depicts a general scheme for the preparation of digital sol-gel inkjet inks according to the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0123] Formulations of the invention, such as those listed in Tables 1-12 have been prepared and have been printed on a variety of surfaces. In some instances, the surface was a dry surface made of a polymeric material, a plastic, a textile and others, and in some cases printing was achieved on a wet surface.

[0124] Also, in some runs, the catalyst formulation was printed ahead of the ink formulation. The catalyst formulation was either allowed to dry prior to application of the ink formulation or was maintained wet or partially wet when the ink formulation was applied.

[0125] As stated above, printing of formulations of the invention provided stable and un-deformable patterns on the variety of surfaces. In contrast, where a polymer was present in the pigment formulation the pattern sensitivity to external stress was dramatically increased. However, in formulations of the invention, where such a polymer was absent, mechanical deformations were prevented or minimized.

[0126] Also, the low temperature curing was found superior when using the complex systems involving latent acids/bases or anti-bleedings systems were used. Both allowed for the formation of strong, un-peelable and un-deformable patterns.