Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • 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
  • C09D11/00—Inks
  • C09D11/30—Inkjet printing inks
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F33/00—Other mixers; Mixing plants; Combinations of mixers
  • B01F33/80—Mixing plants; Combinations of mixers
  • B01F33/84—Mixing plants with mixing receptacles receiving material dispensed from several component receptacles, e.g. paint tins
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
  • B01F35/20—Measuring; Control or regulation
  • B01F35/21—Measuring
  • B01F35/2131—Colour or luminescence
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
  • B01F35/20—Measuring; Control or regulation
  • B01F35/22—Control or regulation
  • B01F35/2201—Control or regulation characterised by the type of control technique used
  • B01F35/2202—Controlling the mixing process by feed-back, i.e. a measured parameter of the mixture is measured, compared with the set-value and the feed values are corrected
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
  • B01F35/80—Forming a predetermined ratio of the substances to be mixed
  • B01F35/82—Forming a predetermined ratio of the substances to be mixed by adding a material to be mixed to a mixture in response to a detected feature, e.g. density, radioactivity, consumed power or colour
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • 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
  • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
  • G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
  • G01J3/46—Measurement of colour; Colour measuring devices, e.g. colorimeters
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
  • G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
  • G01J3/46—Measurement of colour; Colour measuring devices, e.g. colorimeters
  • G01J3/463—Colour matching
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F2101/00—Mixing characterised by the nature of the mixed materials or by the application field
  • B01F2101/30—Mixing paints or paint ingredients, e.g. pigments, dyes, colours, lacquers or enamel
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B7/00—Mixing; Kneading
  • B29B7/02—Mixing; Kneading non-continuous, with mechanical mixing or kneading devices, i.e. batch type
  • B29B7/22—Component parts, details or accessories; Auxiliary operations
  • B29B7/24—Component parts, details or accessories; Auxiliary operations for feeding
  • B29B7/242—Component parts, details or accessories; Auxiliary operations for feeding in measured doses
  • B29B7/244—Component parts, details or accessories; Auxiliary operations for feeding in measured doses of several materials
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B7/00—Mixing; Kneading
  • B29B7/02—Mixing; Kneading non-continuous, with mechanical mixing or kneading devices, i.e. batch type
  • B29B7/22—Component parts, details or accessories; Auxiliary operations
  • B29B7/28—Component parts, details or accessories; Auxiliary operations for measuring, controlling or regulating, e.g. viscosity control
  • B29B7/283—Component parts, details or accessories; Auxiliary operations for measuring, controlling or regulating, e.g. viscosity control measuring data of the driving system, e.g. torque, speed, power

Definitions

• This invention relates to a rapid process for making transparent tints that match the color and strength of a standard tint, using the light transmittance properties of the tints in the wet to bring them within an acceptable match to the standard.
• Transparent tints are widely used nowadays in formulating metallic coating compositions used in particular for exterior finishes for automobiles and trucks.
• the transparent tints contain pigments with extremely small particle sizes (typically less than 0.4 micron in size) so that they impart the desired color to the coating without detracting from its transparency and clarity. This permits the metallic pigments, e.g., aluminum flake or pearlescent pigments, that are used in combination with the transparent tints, to show through and provide the finish with metallic glamour and maximum flop.
• the invention relates to a rapid process for making a transparent tint that matches the color and tinting strength of a standard tint, which involves the use of an improved wet shading technique that measures the light transmittance of the tint in the wet over the visible spectrum and quickly determines therefrom with precision the amount of components of the tint which must be added to bring the tint within an acceptable color and strength tolerance which provides a good wet and dry match to the standard.
• the process of this invention is particularly useful in the production of transparent tints for high performance metallic coatings for automobile and truck exteriors, but can also find use in the manufacture of other paints, printing inks, ink jet inks and other colored products using transparent tints.
• the process for manufacturing transparent tints involves the following:
• a transparent tint such as clear polymer binder for the tint, solvent for the tint, and colorant in the form of a pigment dispersion, transparent tint or dye solution in a mixing vessel;
• step (g) adding to the tint being manufactured the quantities of components calculated in step (f);
• the process might also comprise: (i) adjusting the pathlength of the transmittance cell so that it is the same when measuring the light transmittance of the tint being made as it was when measuring the standard tint.
• the process may further comprises:
• the invention utilizes a computer to perform the necessary calculations.
• the invention provides an automated computer controlled batch or continuous process for the manufacture of transparent tints that utilizes on-line testing of the tints.
• FIG. 1 shows a schematic diagram of the process of the invention used to make transparent tints that match a standard tint within acceptable tolerances, and also demonstrates the possibility of having an on-line color and strength measuring and shading system.
• the process of this invention produces a transparent tint having a color and tinting strength that accurately matches the color and strength of a standard liquid tint through the use of wet spectral transmittance readings of the tint over the visible spectrum with confidence that the wet readings will lead to a good match in the dry.
• the high quality transparent tints produced by the process of this invention are particularly useful in formulating high performance coating compositions and in particular metallic colorcoat or basecoat compositions for clearcoat/colorcoat finishes for automobile and truck exteriors.
• a computer is used to facilitate the required calculations. Although less preferred, calculations can also be done by hand.
• the spectrophotometer can be any commercially available unit capable of measuring spectral transmittance over the visible spectrum of the wet tint being manufactured and generating spectral transmittance curves and L*, a* and b* or other suitable color values therefrom.
• the optical pathlength of the transmittance cell is set low enough to allow sufficient light throughput to be accurately measured by the detectors, yet high enough to avoid saturation of the detectors.
• Pathlengths are typically set between 10-250 microns, preferably 20-75 microns. However, for some optically dense tints, dilution may be necessary to obtain full spectral information.
• Temperature of the measurement cell and the liquid within the cell are held to a narrow enough range such that thermal expansion does not change the effective pathlength and such that the standard and sample readings are comparable.
• the liquid standard and test sample are measured at the same pathlength and in the same temperature range to insure uniform comparisons.
• the data for the liquid standard can optionally be retrieved from stored data from previous measurements. Transmittance measurements are carried out in either direct transmittance mode or diffuse transmittance mode, depending on the level of scattering in the tint components.
• the formula of the tint being manufactured describing the amount of colorants, binders, solvents and other additives required to make a certain volume of a batch of tint is fed into the computer.
• the L*, a* and b* for the standard liquid tint and the permissible L*, a*, b* color values such as color tolerance values (i.e., the allowable variation from standard in each of these three dimensions) at a specified pathlength for the tint being made are also fed into the computer.
• Matching these L*, a*, b* values of the standard within these tolerances assures a match in Lightness, Chroma and Hue, thus matching both color and strength.
• the color vector values of the colorant solutions or dispersions used to formulate the tint are known, these values are also fed into the computer so that the computer can calculate the amount of colorant required to bring the paint within color tolerance. If the color vector values of the colorants are unknown, the color vector values of each colorant are generated by the computer by measuring the L*, a*, b* values of a tint before and after an addition of a known amount of colorant and determining the change in L*, a*, b* values resulting from the addition.
• the color shading technology used in the process is well known and is fully discussed in Falcoff et al. U.S. Patent No. 4,403,866, issued September 13, 1983, hereby incorporated by reference.
• the spectrophotometer 12 which is coupled to a visible light source 14, and transmittance cell 16 utilized in the process are either positioned at a remote location from the mixing vessel for off-line testing or, as shown in Fig. 1 , connected via fluid line 18 to the mixing vessel 20 for on-line testing of the wet tint.
• the wet tint is simply transferred directly to a transmittance cell coupled to the spectrophotometer for spectral measurement. Allowing the tint to flow through the cell directly from the mixing vessel allows for on-line and continuous tint testing and enables automated tint manufacture in a batch or continuous mode.
• the components used to make the transparent tint i.e., colorant in the form of a pigment dispersion (MBj, MB 2 ) or dye solution (Dj), clear binder (CBi) for the tint, solvent (Si) and optional other additives such as tinting solutions (Tj, T ), are preferably metered into a mixing vessel 20 containing a mixer 22 having a mixing head attached to a shaft and driven by a motor.
• the mixing vessel can be any commercially available unit that is capable of achieving the necessary homogenization of the components. In cases where the tint or colorants are prone to flocculation, a high shear mixer is preferred. It is also preferred to use a mixer and metering equipment that are controlled by the computer.
• the components are then thoroughly blended together to form a liquid tint composition.
• the liquid tint is then passed via fluid line 18 and pump 24, through a transmittance cell 16 which is coupled to the spectrophotometer 12 for measurement.
• the cell has a viewing window which is transparent to the visible light spectrum and usually is made of quartz or sapphire glass.
• tint flow through the cell is set sufficiently high to provide a constant interface that can be measured by the spectrophotometer and to prevent build-up of deposits on the cell windows. This improves the measurement accuracy and also retards settling or flocculation of the pigments in the tint.
• transmittance can be advantageously measured in a static sample without flow.
• neat samples of the batch that have been extracted from the mixing vessel might have to be diluted with a diluent such as clear binder/solvent blend to achieve desired lightness and spectral information.
• the spectrophotometer 12 used in the process is electrically connected to the computer 10 and preferably measures the transmittance of the wet tint being prepared over the visible spectrum, calculates L*, a*, b* or other suitable color values from the spectral transmittance curve, and feeds this data back to the computer.
• the spectrophotometer will take spectral transmittance measurements and determine the spectral curve of the tint through the visible spectrum of 400-700 nanometers (nm) at 10 nm increments.
• the computer takes these L*, a* and b* values and determines the difference between the L*, a*, b* values of the tint being prepared and tolerance values for the standard tint ( ⁇ L*, ⁇ a*, ⁇ b*). With the color vector information of the colorants and the ⁇ L*, ⁇ a*, ⁇ b*, the computer determines the amounts of clear binder and colorants to be added to bring the batch within the desired tolerances. These same computations can also be done with the tolerances and vectors specified in ⁇ L*, ⁇ c* and ⁇ h* which give a more direct indication of lightness, chroma and hue.
• the units are a mathematical transformation from L*, a* and b*.
• Addition of the calculated amount of components to the batch may be made manually or automatically. After the addition and mixing of the prescribed quantities of components, the above spectral transmittance measurements and calculations are again made and if the color and strength fall outside of the tolerance values, the process is repeated until the tint being prepared is within the desired tolerances.
• the tint After the tint is prepared to meet the required color and strength tolerance, it can be filled into suitable containers 26 either automatically or manually using conventional filling equipment and procedures.
• the entire tint manufacturing process can be controlled by a computer as shown in Fig. 1. If the computer is electrically connected to the mixer, to the metering pumps which control the supply of a component used in the tint, and to the spectrophotometer, the computer can initiate the addition of accurately measured amounts of each component based on the spectrophotometric readings and resultant calculations. The computer can also halt the mixer and automatically dispense the tint from the mixing vessel after the tint is prepared.
• the process of this invention is particularly useful in the production of transparent tints for high performance metallic coatings for automobile and truck exteriors, but can also find use in the manufacture of other paints, printing inks, ink jet inks and other colored products using transparent tints.
• a variation of this invention is to use the same process with spectral transmittance measurements on precision coatings, drawdowns or sprayouts of the tints over a transparent substrate such as Mylar® film.
• the following Examples illustrate the invention.
• Dry color values for the standard green tint were established using the traditional process of mixing with white, spraying onto panels, baking the panels and measuring the reflected color of the dry panels.
• Wet color values for the standard were established using wet transmittance at the same pathlength and dilution as the test batch. These values were recorded:
• Tolerance values for L*, a* and b* for this tint are +/-0.3.
• color vector values for the tint shading components were established by adding known amounts of the components to the standard tint and measuring the resulting color differences in wet transmittance. Results are as follows:
• the computer calculated the amounts of components to be added to the dispersion to bring it into a wet match and the standard. The following amounts were added manually to the batch:
• the dry values are within the tolerance values, indicating that an acceptable tint was produced. Additionally, the wet differences in color and strength between batch and standard matched those in the dry extremely well.

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• Chemical & Material Sciences (AREA)
• Physics & Mathematics (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Wood Science & Technology (AREA)
• Materials Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Spectrometry And Color Measurement (AREA)
• Paints Or Removers (AREA)
• Inks, Pencil-Leads, Or Crayons (AREA)
• Investigating Or Analysing Materials By Optical Means (AREA)

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• 2002
  • 2002-03-13 US US10/097,991 patent/US6719452B2/en not_active Expired - Lifetime
  • 2002-03-14 EP EP02763846A patent/EP1379847A1/en not_active Withdrawn
  • 2002-03-14 KR KR20037012157A patent/KR20030083745A/ko not_active Withdrawn
  • 2002-03-14 JP JP2002579752A patent/JP2004532407A/ja active Pending
  • 2002-03-14 CA CA002438281A patent/CA2438281A1/en not_active Abandoned
  • 2002-03-14 MX MXPA03008436A patent/MXPA03008436A/es not_active Application Discontinuation
  • 2002-03-14 WO PCT/US2002/007875 patent/WO2002082026A1/en not_active Ceased
  • 2002-03-14 BR BR0208617-4A patent/BR0208617A/pt not_active IP Right Cessation

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