# US 2007/0161115 A1 · Method for determining ink usage efficiency in commercial printing processes using pigments and quantitative tests > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2007/0161115 A1 - Document ID: US20070161115A1 - Status: Published application - Kind: A1 - Application number: 11/332,668 - Filed: 2006-01-12 - Published: 2007-07-12 - Earliest claimed: 2006-01-12 - Assignees: Sun Chemical Corporation - Inventors: Russell Schwartz; Constantinos Nicolaou; Xin Zhang; Donald Henderson - Web page: https://patentgrep.com/patent/US20070161115A1 ## CPC - G01N 21/31: Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry {(G01N21/72 takes precedence)} - C09D 11/03: characterised by features other than the chemical nature of the binder - G01N 1/4055: {by solubility techniques} - G01N 33/32: Paints; Inks - G01N 2021/5942: {for dot area ratio in printing applications} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) ## Abstract A method for determining printing ink usage efficiency (weight of ink required to print a given area) in a printing process is disclosed where the method is based on the analysis of pigment in said printed ## Claims ### Claim 1 A method for determining printing ink usage efficiency in a printing process based on an analysis of a pigment in a printed ink, said method comprising: (a) extracting said printed ink containing said pigment from a printed surface area into a liquid solution; (b) measuring amount of said pigment in the extracted ink; and (c) calculating said printing ink usage efficiency based on the analysis of and the amount of pigment in said area. ### Claim 2 (depends on 1) The method of claim 1, wherein the pigment absorbs UV-Visible light. ### Claim 3 (depends on 1) The method of claim 1, wherein said pigment is selected from the group consisting of azo and phthalocyanine pigments. ### Claim 4 (depends on 2) The method of claim 2, wherein the measurement of the amount of said pigment in extracted ink comprises: (a) placing said liquid solution in a container transparent to UV-Visible light; (b) measuring absorbance amount of said pigment in extracted ink by UV-Visible spectrophotometry at a specific wavelength; and (c) calculating concentration of said pigment using the following equation: c=A/aλb where A is the measured absorbance, aλ is an absorptivity coefficient of said pigment and is dependent on said wavelength, b is the path length of said container, and c is the pigment concentration in said liquid solution; and (d) calculating absolute amount of said pigment in said liquid solution. ### Claim 5 (depends on 1) The method of claim 1, wherein said ink is selected from the group consisting of publication inks and packaging inks. ### Claim 6 (depends on 5) The method of claim 5, wherein said ink is selected from the group of gravure inks, flexo inks and offset inks. ### Claim 7 (depends on 1) The method of claim 1, wherein said printed surface area contains a color bar or registration mark. ### Claim 8 (depends on 1) The method of claim 1, wherein said printed surface area is from about 2 mm2 to about 1575 mm2. ### Claim 9 (depends on 1) The method of claim 1, wherein said printing ink usage efficiency is expressed in m2/kg of printing ink. ### Claim 10 (depends on 1) The method of claim 1, wherein said liquid solution is filtered prior to step (b). ### Claim 11 (depends on 1) The method of claim 1, wherein Optical Density is measured for said printed area prior to the extraction of step (a). ### Claim 12 (depends on 11) The method of claim 11, wherein said ink usage efficiency is expressed as ink usage efficiency at a measured Optical Density. ### Claim 13 (depends on 1) The method of claim 1 further comprising measuring the reflectance color saturation for said printed area prior to the extraction of step (a). ### Claim 14 (depends on 4) The method of claim 4, wherein said absorptivity coefficient aλ is expressed as Liters mg−1cm−1. ### Claim 15 (depends on 14) The method of claim 14, wherein said pigment concentration c is expressed in mg/Liter. ### Claim 16 (depends on 1) The method of claim 1, wherein the liquid solution used to extract said printing ink is selected from the group consisting of ortho-dichlorobenzene, 1-methylnaphthalene and acidified aqueous ethanol. ### Claim 17 (depends on 1) The method of claim 1, wherein said liquid solution used to extract said printing ink is ortho-dichlorobenzene and said pigment is an azo yellow pigment. ### Claim 18 (depends on 1) The method of claim 1, wherein said liquid solution used to extract said printing ink is 1-methylnaphthalene and said pigment is a phthalocyanine pigment. ### Claim 19 (depends on 1) The method of claim 1, wherein said liquid solution used to extract said printing ink is an acidified aqueous ethanol and said pigment is an azo magenta pigment. ### Claim 20 (depends on 12) A method for determining ink usage efficiency at a desired Optical Density or at SWOP density comprising: (a) determining ink usage efficiency at measured Optical Density according to claim 12; and (b) determining ink usage efficiency at SWOP density according to the following formula: ink usage efficiency at SWOP density=(ink usage efficiency at measured Optical Density)·(C.F.), wherein C.F. is a correction factor to adjust for variation in pigment saturation within a given SWOP Optical Density range. ### Claim 21 (depends on 1) A Product comprising printed ink, wherein the printing ink usage efficiency of said ink was determined according to the method of claim 1.