US 5,665,151 A · Method for making article with and detecting water based inks containing near infrared fluorophores

Abstract

The present invention provides inks which contain a near infrared fluorophoric compound incorporated into a water-dissipatible polyester backbone. The inks of the present invention are preferably colorless or "invisible" but could be made slightly colored if desirable. Specifically, the inks of the present invention comprise: A. between about 1 and 10 weight percent of at least one water-dissipatable polyester having from about 0.1 ppm by weight to about 10% by weight of a thermally stable near infrared fluorophoric compound copolymerized therein; B. between about 5 and 75 weight percent of at least aliphatic humectant; C. between about 0 and 15 weight percent of at least one lower aliphatic alcohol of no more than 3 carbon atoms; D. water and optionally up to about 2 weight percent of one or more additives; wherein the weight percentages of components A-D equal 100%.

Drawings

Drawings are temporarily unavailable. Open the PDF at USPTO

Drawings

Claims21

Dependent claims

A method for invisibly marking, for identification purposes, an article with a water-dispersible polymer, wherein said polymer has from about 0.1 to about 10.0 ppm of a residue of a near infrared flourescing compound copolymerized therein, which comprises applying to said article a composition comprising

A. between about 1 and 10 weight percent of at least one water-dissipatable polyester comprising:
(i) monomer residues of at least one dicarboxylic acid;
(ii) about 4 to 25 mole percent, based on the total of all acid, hydroxy and amino equivalents, of monomer residues of at least one difunctional sulfomonomer containing at least one sulfonate group bonded to an aromatic ring where the functional groups are selected from the group consisting of hydroxy, carboxyl, carboxylate ester and amino;
(iii) monomer residues of at least one diol or a mixture of diol and a diamine;
and optionally,
(iv) monomer residues of at least one difunctional monomer reactant selected from the group consisting of hydroxycarboxylic acids, amino carboxylic acids and aminoalkanols;
provided that at least 20 percent of the groups linking the monomeric units are ester linkages;
said water-dissipatable polyester having from about 0.1 ppm by weight to about 10% by weight of a thermally stable near infrared fluorophoric compound copolymerized therein;
B. between about 5 and 75 weight percent of at least one humectant;
C. between about 0 and 15 weight percent of at least one lower aliphatic alcohol of no more than 3 carbon atoms;
D. water and optionally up to about 2 weight percent of one or more additives;
wherein the weight percentages of components A-D equal 100%.

9 more elements

A method for detecting an invisible mark on an article comprising the steps of exposing said marked article to infrared radiation sufficient to cause said mark to fluoresce and detecting said fluorescence, wherein said mark is formed from an ink comprising

A. between about 1 and 10 weight percent of at least one water-dissipatable polyester comprising:
(i) monomer residues of at least one dicarboxylic acid;
(ii) about 4 to 25 mole percent, based on the total of all acid, hydroxy and amino equivalents, of monomer residues of at least one difunctional sulfomonomer containing at least one sulfonate group bonded to an aromatic ring where the functional groups are selected from the group consisting of hydroxy, carboxyl, carboxylate ester and amino;
(iii) monomer residues of at least one diol or a mixture of diol and a diamine;
and optionally,
(iv) monomer residues of at least one difunctional monomer reactant selected from the group consisting of hydroxycarboxylic acids, amino carboxylic acids and aminoalkanols;
provided that at least 20 percent of the groups linking the monomeric units are ester linkages;
said water-dissipatable polyester having from about 0.1 ppm by weight to about 10% by weight of a thermally stable near infrared fluorophoric compound copolymerized therein;
B. between about 5 and 75 weight percent of at least one humectant;
C. between about 0 and 15 weight percent of at least one lower aliphatic alcohol of no more than 3 carbon atoms;
D. water and optionally up to about 2 weight percent of one or more additives;
wherein the weight percentages of components A-D equal 100%.

9 more elements

Dependencies are inferred from the claim text.

Description8,033 words

Summary660 words

#This invention relates to aqueous ink formulations suitable for ink jet printing, both by drop-on-demand (DOD) and continuous printing methods, and which contain sulfopolyesters/amides having near infrared fluorophores copolymerized therein.

#It is desirable to provide intelligible markings that are virtually invisible to the human eye on the surface of articles for identification, authentication, sorting, etc. U.S. Pat. Nos. 5,093,147; 5,336,714 disclose using certain near infrared fluorescent compounds having minimal light absorption of radiation in the visible range 400-700 nanometers (nm) and strong light absorption in the near infrared region about 700-900 nm with accompanying fluorescence to produce fluorescent radiation of wavelengths longer than the wavelength of excitation. However, aqueous ink formulations suitable for ink jet printing are not disclosed and markings produced from those compounds do not have adequate stability to sunlight/ultraviolet (UV) light to permit practical marking speeds required for suitable intelligible markings.

#The polymeric compositions used in U.S. Pat. No. 5,336,714 are unique in that the near infrared fluorophores (NIRF's) are copolymerized therein and thus are not extractable, exudable, sublimable or leachable from the polymeric composition. The phthalocyanines and naphthalocyanines mentioned therein are unique in that they provide improved UV light stability over the known cyanine laser dyes used in U.S. Pat. No. 5,093,147. However, U.S. Pat. No. 5,336,714 provides no help in formulating an aqueous based ink suitable for ink jet printing using the polymeric compositions containing the copolymerized NIRF compound.

Detailed description7,373 words

#This invention relates to an aqueous ink composition suitable for use in ink jet printing comprising:

#A. between about 1 and 10 weight percent of at least one water-dissipatable polyester comprising:

#(i) monomer residues of at least one dicarboxylic acid;

Facts

Application

08/751,629Filed 18 Nov 1996 · division

Priority

23 Oct 1995

Granted

9 Sep 1997

Term ended

23 Oct 2015

Estimated · how

20 years from earliest known nonprovisional domestic filing. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination. Patent term adjustment is unavailable; no adjustment was added.

Classification9 codes

C09D 11/104
Containing macromolecular compounds obtained by reactions other than those only involving unsaturated carbon-to-carbon bonds: polyesters
C08G 63/6856
Derived from polycarboxylic acids and polyhydroxy compounds: dicarboxylic acids and dihydroxy compounds
C08G 63/6886
Derived from polycarboxylic acids and polyhydroxy compounds: dicarboxylic acids and dihydroxy compounds
C09D 11/30
Inks: inkjet printing inks

Method for making article with and detecting water based inks containing near infrared fluorophores

Life of this patent

Method for making article with and detecting water based inks containing near infrared fluorophores

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims21

Description8,033 words

Drawings

Classification9 codes

Life of this patent

Description8,033 words