US20160002474A1 - Infrared-reflective coatings - Google Patents
Infrared-reflective coatings Download PDFInfo
- Publication number
- US20160002474A1 US20160002474A1 US14/855,868 US201514855868A US2016002474A1 US 20160002474 A1 US20160002474 A1 US 20160002474A1 US 201514855868 A US201514855868 A US 201514855868A US 2016002474 A1 US2016002474 A1 US 2016002474A1
- Authority
- US
- United States
- Prior art keywords
- titanium dioxide
- infrared
- clusters
- coating
- reflective
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
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
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
- C09D5/004—Reflecting paints; Signal paints
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/0018—Coating or impregnating "in situ", e.g. impregnating of artificial stone by subsequent melting of a compound added to the artificial stone composition
-
- 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
- C09D123/00—Coating compositions based on homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Coating compositions based on derivatives of such polymers
- C09D123/02—Coating compositions based on homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Coating compositions based on derivatives of such polymers not modified by chemical after-treatment
- C09D123/04—Homopolymers or copolymers of ethene
- C09D123/06—Polyethene
-
- 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
- C09D125/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Coating compositions based on derivatives of such polymers
- C09D125/02—Homopolymers or copolymers of hydrocarbons
- C09D125/04—Homopolymers or copolymers of styrene
- C09D125/08—Copolymers of styrene
- C09D125/14—Copolymers of styrene with unsaturated esters
-
- 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
- C09D131/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an acyloxy radical of a saturated carboxylic acid, of carbonic acid, or of a haloformic acid; Coating compositions based on derivatives of such polymers
- C09D131/02—Homopolymers or copolymers of esters of monocarboxylic acids
- C09D131/04—Homopolymers or copolymers of vinyl acetate
-
- 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
- C09D133/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Coating compositions based on derivatives of such polymers
-
- 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
- C09D155/00—Coating compositions based on homopolymers or copolymers, obtained by polymerisation reactions only involving carbon-to-carbon unsaturated bonds, not provided for in groups C09D123/00 - C09D153/00
- C09D155/02—ABS [Acrylonitrile-Butadiene-Styrene] polymers
-
- 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
- C09D161/00—Coating compositions based on condensation polymers of aldehydes or ketones; Coating compositions based on derivatives of such polymers
- C09D161/04—Condensation polymers of aldehydes or ketones with phenols only
- C09D161/06—Condensation polymers of aldehydes or ketones with phenols only of aldehydes with phenols
-
- 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
- C09D161/00—Coating compositions based on condensation polymers of aldehydes or ketones; Coating compositions based on derivatives of such polymers
- C09D161/20—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
- C09D161/26—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds
- C09D161/28—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds with melamine
-
- 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
- C09D163/00—Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
-
- 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
- C09D167/00—Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain; Coating compositions based on derivatives of such polymers
-
- 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
- C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
- C09D175/04—Polyurethanes
-
- 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
- C09D177/00—Coating compositions based on polyamides obtained by reactions forming a carboxylic amide link in the main chain; Coating compositions based on derivatives of such polymers
-
- 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
- C09D183/00—Coating compositions based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon, with or without sulfur, nitrogen, oxygen, or carbon only; Coating compositions based on derivatives of such polymers
- C09D183/04—Polysiloxanes
-
- 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
- C09D7/40—Additives
- C09D7/60—Additives non-macromolecular
- C09D7/61—Additives non-macromolecular inorganic
-
- 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
- C09D7/40—Additives
- C09D7/66—Additives characterised by particle size
- C09D7/68—Particle size between 100-1000 nm
-
- 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
- C09D7/40—Additives
- C09D7/66—Additives characterised by particle size
- C09D7/69—Particle size larger than 1000 nm
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
- E04D1/00—Roof covering by making use of tiles, slates, shingles, or other small roofing elements
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
- E04D3/00—Roof covering by making use of flat or curved slabs or stiff sheets
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
- E04D5/00—Roof covering by making use of flexible material, e.g. supplied in roll form
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04D—ROOF COVERINGS; SKY-LIGHTS; GUTTERS; ROOF-WORKING TOOLS
- E04D7/00—Roof covering exclusively consisting of sealing masses applied in situ; Gravelling of flat roofs
- E04D7/005—Roof covering exclusively consisting of sealing masses applied in situ; Gravelling of flat roofs characterised by loose or embedded gravel or granules as an outer protection of the roof covering
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2237—Oxides; Hydroxides of metals of titanium
- C08K2003/2241—Titanium dioxide
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L61/00—Compositions of condensation polymers of aldehydes or ketones; Compositions of derivatives of such polymers
- C08L61/20—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen
- C08L61/26—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds
- C08L61/28—Condensation polymers of aldehydes or ketones with only compounds containing hydrogen attached to nitrogen of aldehydes with heterocyclic compounds with melamine
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/24—Structural elements or technologies for improving thermal insulation
- Y02A30/254—Roof garden systems; Roof coverings with high solar reflectance
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B80/00—Architectural or constructional elements improving the thermal performance of buildings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/24—Structurally defined web or sheet [e.g., overall dimension, etc.]
- Y10T428/24355—Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
- Y10T428/24372—Particulate matter
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/25—Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
Definitions
- inventive concepts disclosed and claimed herein relate generally to a coating composition and, more particularly, but not by way of limitation, to a composition having infrared-reflective clusters of titanium dioxide particles cemented together with a precipitate.
- An important approach for reducing air conditioning requirements is to use roofing products that reflect solar radiation. Radiation is the transfer of heat through electromagnetic energy, typically solar radiation. Absorption of radiation causes an increase in temperature at the absorbing surface and a transfer of the heat to underlying surfaces. In situations where it is desirable to reduce heating due to solar radiation, surfaces exposed to the solar radiation are treated to reflect or scatter the radiation rather than absorb it.
- Solar radiation received on the surface of the earth comprises mostly visible and near-infrared (NIR) wavelengths, with NIR consisting of more than half of the total solar radiation. Visible wavelengths are those from about 400 nm to 700 nm while NIR wavelengths are those from about 700 nm to 2500 nm. Absorption of certain visible wavelengths and reflection of the un-absorbed visible light provides color. Coatings typically include colored pigments to obtain a desired color. For example, the color blue is obtained by using blue pigment to absorb most of the non-blue visible light with wavelengths longer than 460 nm.
- black surfaces and ones having a dark color tend to absorb solar radiation causing an increase in the surface temperature.
- white surfaces tend to reflect or scatter solar radiation, causing much less heating. While white surfaces offer desirable heat absorption properties, in many applications the lack of surface color is aesthetically unpleasing. Since the human eye can not see infrared light, the absorption or reflection of the infrared light by the colorants bears no consequence on the color of the coatings. Thus, a surface coating should ideally absorb only the visible radiation necessary to provide the desired color, and absorb none of the NIR radiation.
- a composition comprising a polymer with infrared-reflective clusters of titanium dioxide primary particles dispersed therein.
- the titanium dioxide primary particles are cemented together with a precipitate to form clusters.
- the titanium dioxide primary particles have an average particle diameter in the range of from about 0.15 to about 0.35 micron, the clusters of titanium dioxide primary particles have a geometric mass mean diameter in the range of from about 0.38 to about 5 microns, and the clusters of titanium dioxide primary particles have a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5.
- GSD geometric standard deviation
- a method of reducing radiant energy absorption includes the following steps.
- a coating precursor is provided having therein infrared-reflective clusters of titanium dioxide primary particles.
- the titanium dioxide primary particles are cemented together with precipitated silica and/or alumina to form the clusters as described above.
- the coating precursor is then applied to a surface to form an infrared reflective coating upon drying or curing.
- an infrared-reflective roofing article having a base substrate with an upper surface, and a water resistant coating material covering at least a portion of the upper surface of the base substrate.
- the coating material includes infrared-reflective clusters of titanium dioxide primary particles.
- the titanium dioxide primary particles are cemented together with precipitated silica and/or alumina to form the clusters as described above.
- a metal coil at least partially coated with a coating material comprising the above-described infrared-reflective clusters is provided.
- infrared-reflective roofing granules are provided.
- the infrared-reflective roofing granules include base rock or mineral granules covered with a water resistant coating material comprising the above-described infrared-reflective clusters.
- a method of making infrared-reflective clusters of titanium dioxide primary particles includes the following steps.
- An aqueous slurry of titanium dioxide particles is treated to deposit precipitated silica and/or alumina on the titanium dioxide particles.
- the slurry of treated titanium dioxide particles is then dried to form titanium dioxide clusters having a geometric mass mean diameter in the range of from about 0.38 to about 5 microns, while the clusters of titanium dioxide particles have a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5.
- GSD geometric standard deviation
- the titanium dioxide clusters are packaged without micronization such that the titanium dioxide clusters retain a geometric mass mean diameter in the range of from about 0.38 to about 5 microns.
- a method of making infrared-reflective clusters of titanium dioxide primary particles includes the following steps. An aqueous slurry of titanium dioxide particles is treated to deposit precipitated silica and/or alumina on the titanium dioxide particles. The slurry of treated titanium dioxide particles is then dried to form titanium dioxide clusters having a geometric mass mean in a range of from about 0.38 to about 5 microns, while the clusters of titanium dioxide particles have a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5.
- GSD geometric standard deviation
- the titanium dioxide clusters are fed through a micronizing system using steam or air pressure low enough to result in product titanium dioxide clusters retaining a geometric mass mean diameter in the range of from about 0.38 to about 5 microns and a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5.
- GSD geometric standard deviation
- a method of making an infra-red reflective coating includes dispersing the infrared-reflective cluster of titanium dioxide primary particles described above into a coating formulation.
- FIG. 1 is a graphical representation of the theoretical scattering efficiency for different particle sizes of TiO 2 .
- FIG. 2 is a graphical representation of the reflectance measurements comparing RCL-6TM and RCL-6TM SDD, as represented by samples 5a and 5b from Comparative Example 2.
- FIG. 3 is a graphical representation of the reflectance measurements comparing TIONA®-696 and TIONA®-696 SDD, as represented by samples 6a and 6b from Comparative Example 2.
- FIG. 4 is a graphical representation of the reflectance measurements comparing TIONA®-696 and TIONA®-696 SDD, as represented by samples 10a and 10b from Comparative Example 3.
- FIG. 5 is a graphical representation of the reflectance measurements comparing TIONA®-696 and TIONA®-696 SDD, as represented by samples 14a and 14b from Comparative Example 4.
- Solar radiation at sea level consists of three wavelength regions: Ultraviolet (UV), Visible, and Infrared (IR).
- the UV wavelengths are from 280 nm to 400 nm.
- the visible wavelengths are from 400 nm to 700 nm.
- the IR wavelengths are from 700 nm to 2500 nm.
- the energy of the solar radiation in each region is about 4%, 42%, and 54%, respectively, for the UV, Visible, and Infrared.
- Normal coatings are made with pigments and an organic or inorganic vehicle.
- the pigments are used to either absorb or reflect visible light.
- the vehicle is used to bind the pigments in the coating.
- Titanium dioxide with high refractive indices for visible and infrared wavelengths, is an excellent material for reflecting solar radiation.
- normal titanium dioxide (TiO 2 ) pigments while designed to scatter or reflect visible light, have been found to also strongly scatter or reflect NIR light.
- TiO 2 pigment particles are more efficient for scattering light of shorter wavelengths (e.g., blue); and larger particles are more efficient for scattering longer wavelengths (e.g., red and infrared). This has been verified by practical measurement, showing that the optimal particle size for light scattering is about one-half of the light wavelength (e.g. 0.24 ⁇ rutile TiO 2 for green light at 560 nm). Referring now to FIG. 1 , one can see the theoretical effect of TiO 2 particle size on scattering efficiency in the visible and IR wavelengths.
- TiO 2 pigment has a geometric mass mean particle size of about 0.30 micron and a geometric standard deviation (GSD) of about 1.50 such that visible light scattering efficiencies are optimized to produce a high tinting strength. However, the IR scattering efficiencies are rather weak. As the mean particle size and GSD increase, the visible scattering efficiencies decrease; however, the IR scattering efficiencies remain about the same. These light scattering calculations show that the optimal particle size of TiO 2 for reflecting the maximum amount of solar infrared light is at about 0.40 micrometer (p) and higher.
- GSD geometric standard deviation
- TiO 2 particles require a trade-off. At a particle size of 0.40 ⁇ , TiO 2 also scatters significant visible light. Using TiO 2 pigment with a high visible light scattering efficiency will yield good opacity or hiding power in coatings; however, it will also necessitate an increased usage of color pigments to obtain the same desired color/shade level. Color pigments absorb NIR, causing additional total heat absorption, and the color pigments used for heat-reflective applications are typically much more expensive than TiO 2 . Considering both the light scattering effect and economics of the more expensive color pigments, additional calculations indicate the optimum size of TiO 2 particles for dark heat-reflecting coatings should be about 0.4 micron and larger.
- titanium dioxide primary particles having an average particle diameter in the range of from about 0.15 to about 0.35 micron, cemented together with a precipitated silica and/or alumina to form infrared-reflective clusters having a geometric mass mean diameter in the range of from about 0.38 to about 5 microns and a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5, can be used to provide coatings with improved infrared-reflective properties.
- a coating composition includes polymer and such infrared-reflective clusters dispersed therein.
- precipitated silica and/or alumina is used herein and in the appended claims to mean that the precipitate referred to can be precipitated silica, precipitated alumina, or combinations of precipitated silica and precipitated alumina.
- the “precipitated silica” and the “precipitated alumina” are discussed in detail hereinafter.
- the term “primary particles” refers to unaggregated or unagglomerated TiO2 crystals.
- Commercial TiO 2 pigment typically has a geometric mass mean particle size in the range of from about 0.2 micron to 0.36 micron and a geometric standard deviation (GSD) in the range of from about 1.40 to about 1.55.
- the infrared-reflective clusters have a geometric mass mean diameter in the range of from about 0.38 to about 1 micron.
- the infrared-reflective clusters have a geometric standard deviation (GSD) in the range of from about from 1.58 to about 2.00.
- the titanium dioxide primary particles may be treated or untreated titanium dioxide obtained directly from a production process such as the chloride or sulfate processes. Further, the TiO 2 can have an anatase or rutile crystal structure. In one embodiment, the TiO 2 primary particles comprise treated or untreated rutile particles produced by the chloride process. Rutile TiO 2 absorbs UV light for wavelengths shorter than 405 nm while anatase TiO 2 absorbs UV light for wavelengths shorter than 385 nm. While the solar UV radiation is largely absorbed and transformed to heat, since the solar radiation is between 385 nm and 400 nm represents only about 0.3% of the total solar radiation, anatase and rutile offer essentially the same heat resistance.
- TiO 2 primary particles can be surface treated with organic or inorganic compounds, such as precipitated oxides of phosphate, titanium, or zirconium prior to cementation with precipitated silica and/or alumina.
- organic or inorganic compounds such as precipitated oxides of phosphate, titanium, or zirconium prior to cementation with precipitated silica and/or alumina.
- TiO 2 pigment surface treatments are known to those skilled in the art and are used to provide properties such as weatherability, durability and enhanced dispersibility in various carriers.
- precipitated silica refers to any silicate; oxide, hydrous oxide, or hydroxide of silicon; and any other silicon and oxygen-containing precipitate from an aqueous soluble silica.
- aqueous soluble silica include sodium silicate and potassium silicate.
- the amount of precipitated silica used to cement the primary TiO 2 particles together is dictated by the desired cluster size.
- the precipitated silica is present in an amount in the range of from about 2 wt % to about 20 wt % based on the weight of titanium dioxide.
- the precipitated silica is present in the clusters in an amount in the range of from about 3 wt % to about 7 wt % based on the weight of TiO 2 in the clusters.
- precipitated alumina refers to any alumina; oxide, hydrous oxide, or hydroxide of aluminum; and any other alumina and oxygen-containing precipitate from an aqueous soluble alumina.
- aqueous soluble alumina include sodium aluminate and aluminum sulfate.
- the amount of precipitated alumina used to cement the primary TiO 2 particles together is dictated by the desired cluster size.
- the precipitated alumina is present in an amount in the range of from about 2 wt % to about 10 wt % based on the weight of titanium dioxide.
- the precipitated alumina is present in the clusters in an amount in the range of from about 3 wt % to about 5 wt % based on the weight of TiO 2 in the clusters.
- a composition containing the above-described clusters can include synthetic or natural polymers and resins and can be either solvent based or water based.
- suitable polymers and resins include, but are not limited to, alkyds, acrylics, vinyl-acrylics, styrene acrylics, vinyl acetate/ethylene (VAE), polyvinyl acetates (PVA), polyurethanes, polyesters, polyamides, phenolics, melamine resins, epoxy, silicones and oils.
- the composition includes the above-described infrared-reflective, silica and/or alumina cemented clusters of titanium dioxide and a polymer such as polyethylene, polyvinyl chloride, thermoplastic olefin, acrylonitrile butadiene styrene, or acrylonitrile-styrene-acrylic.
- the composition can include additional pigmentary titanium dioxide as well as colorants and other additives.
- a method of reducing radiant energy absorption includes providing a coating composition precursor having dispersed therein the infrared-reflective clusters of titanium dioxide described above, and applying the coating composition precursor to a surface to form an infrared reflective coating upon drying or curing.
- the term “curing” is used herein to include processes involving thermosetting, catalysis, UV-curing, and other means for solidifying a coating after application.
- Nonlimiting examples of coating precursor compositions include paint, varnish, curable powder coatings, porcelain enamel powders, molten plastics, and the like.
- Infrared-reflective roofing articles can be prepared by application of a water resistant coating material comprising the infrared-reflective TiO 2 clusters described above to at least a portion of an upper surface of a base substrate.
- suitable base substrates include, but are not limited to, metal coil stock as discussed above, asphalt shingles, ceramic roofing tiles, metal shakes, concrete roofing tiles, cedar shakes, natural slate roofing tiles and synthetic slate roofing tiles.
- the coating composition can be, for example, a standard paint formulation or a metal coil coating.
- Metal coil stock coated with the inventive compositions disclosed herein obtains much improved solar heat resistance.
- Infrared-reflective roofing granules are another application wherein base rock or mineral granules are coated with a water resistant coating material including the infrared-reflective TiO 2 clusters described above.
- Infrared-reflective clusters of TiO 2 primary particles can be made by adding any soluble silica and/or alumina to an aqueous slurry of appropriately sized TiO 2 particles and causing the silica to precipitate by, for example, adjusting the pH.
- Such silica and alumina coating processes are practiced commercially by chloride and sulfate process titanium dioxide pigment manufacturers when making dense-silica treated pigment. Processing can include neutralization of the slurry if necessary, filtration and washing, followed by drying.
- the pigment grades RCL-6TM and TIONA® 696 are super-durable pigments designed for outdoor use. In order to have very good durability, the pigments are treated with dense silica at about 6.5% and 3.5%, respectively.
- the TiO 2 particles are agglomerated together after surface treatment. Particle size measurements show that the mean cluster size of the spray dryer discharge is about 0.6 micrometers. However, commercial pigment is then deagglomerated in a fluid-energy mill such as a micronizer. Micronization is necessary to break up the clusters so that the pigment will efficiently scatter visible light. After micronization, the mean size is reduced to about 0.33 micrometer for RCL-6TM and 0.30 micrometer for TIONA® 696.
- the spray dryer discharge by-passes the micronization step to maintain the necessary agglomeration and high average cluster diameter.
- the spray dryer discharge can be fed to a micronizer operated at greatly reduced steam or air pressure to produce titanium dioxide clusters having a geometric mass mean cluster diameter in the range of from about 0.38 to about 1 micron and a GSD still in the range of from about 1.55 to about 2.5.
- the clusters With the high dense silica treatment on the TiO 2 particles, the clusters also have the high durability required for outdoor applications.
- the particle size distribution of TiO 2 is measured using an optical method. The method was first described by L. W. Richards in Pigment Handbook, Vol. III, p. 89 (1973). A similar method was described by D. F. Tunsdall in the UK Patent, GB2046898 (1980). In this method, the TiO 2 primary particles or clusters are dispersed in water in the form of dilute suspension. The attenuation of light by TiO 2 particles or clusters in the suspension is measured using a UV-VIS spectrophotometer (Perkin-Elmer, Model 2S). The scattering efficiencies or the “optical densities” are measured as a function of the light wavelength.
- the scattering efficiency curve is normalized by setting the value equal to 1 at 440 nm.
- the values are compared with the normalized theoretical calculated scattering efficiency values to determine the particle size distribution of the sample.
- a log-normal distribution of the particles is assumed.
- a series of curves are calculated for the geometric mass mean sizes ranging from 0.200 to 1.00 micrometer and the geometric standard deviations (GSD) ranging from 1.400 to 2.400.
- GSD geometric standard deviations
- the observed particle size distribution approximates a log-normal distribution. Therefore, it is often beneficial to work with particle size distributions on a logarithmic basis.
- the log-normal distribution is based on the normal distribution. It describes a variable, x, where log(x) is normally distributed and is valid for values of x which are greater than zero.
- x log(x) is normally distributed and is valid for values of x which are greater than zero.
- GSD geometric standard deviation
- the spread of a log-normal distribution is controlled by the geometric standard deviation. The smaller the geometric standard deviation, the more concentrated are the data. If one adds percentages, one will see that approximately a) 68% of the distribution lies within the x between Mean/GSD and Mean*GSD; b) 95% of the distribution lies within the x between Mean/(GSD) 2 and Mean*(GSD) 2 ; and c) 99.7% of the distribution lies within the x between Mean/(GSD) 3 and Mean*(GSD) 3 .
- the pigments In the preparation of the wet coatings, the pigments have to be dispersed uniformly in the coating media.
- the dispersion process normally uses a high speed disperser, and optionally, a media (bead) mill.
- a media (bead) mill In the media milling process, products to be dispersed are premixed, and fed to the milling chamber with a metering pump controlling process residence time.
- the water-cooled milling chamber is filled with small media and agitated by a centrally located series of disks creating intense shear and impact forces. Process quality is determined by product feed rate, agitator rotational speed, grinding media type, size and loading, along with product formulation.
- the media mill used to prepare the coating samples is an Eiger Laboratory Mini Mill Model M100 made by Eiger Machinery, Inc.
- the volume of the milling chamber is 100 ml.
- the chamber is filled with 70 ml of the milling media.
- Ceramic media with a density of 4.3 and diameter at 2 mm is used.
- the agitator rotational speed is set at 3000 rpm.
- Samples are premixed using a high speed DISPERMAT® disperser. This disperser has a 2.5′′ Cowles blade and a rotation speed of 3000 rpm is used. The premixed samples are then poured into the feed funnel with the mill operated at low rpm.
- the rpm is increased to the desired level and product is allowed to circulate until the degree of product quality is achieved.
- Product from the feed funnel is pumped into the milling chamber and an agitated bed of grinding beads.
- the agitator rotational speed is electronically controlled.
- Product quality is determined by adjusting the chamber residence time and by adjusting the agitator rotational tip speed and the product formulation.
- Polyester Coil Coating Test Formula Weight (g) White Paint A. Polyester Coil Grind POLYMAC TM 220-1935 resin 116.2 DISPERBYK ® 110 7.1 TiO2 177.6 B. Polyester Coil Letdown Grind (from A) 132.0 POLYMAC ® 220-1935 resin 76.4 CYMEL ® 303 15.1 NACURE ® 2500 1.9 Xylene 23.4 BYK ® 370 1.3 Colorant Paste Shepherd Colorant 50.0 POLYMAC ® 220-1935 resin 47.1 DISPERBYK ® 110 2.9
- POLYMAC® 220-1935 is a thermosetting polyester resin.
- BYK® 370 is a solution of a polyester modified hydroxy functional polydimethylsiloxane, and DISPERBYK® 110 is a dispersing additive.
- CYMEL® 303 is a methylated melamine-formaldehyde resin.
- NACURE® is a curing agent.
- Xylene is an organic solvent.
- TIONA® 696 and RCL-6TM finished products from Millennium Inorganic Chemicals
- TIONA® 696 and RCL-6TM spray dryer discharge samples obtained from Millennium Inorganic Chemicals.
- the color pigments used in the study are from the Shepherd Company. They are mixed metal oxides, including Black 411A, Blue 214, and Green 410.
- the mixture of the resin, dispersing additive, and TiO 2 samples are mixed and then dispersed using a high speed disperser at 3000 rpm for 30 minutes.
- the different grind samples were first dispersed using the high speed disperser and then further dispersed using the Eiger Mill at the grind stage. The samples were further prepared with the letdown stage. After the letdown stage, the Shepherd colorant paste was added. The dispersion of the colorant paste in the coating formulation was accomplished by using the high speed disperser operated at 3500 rpm.
- the colorant paste was prepared by mixing the polyester resin, dispersing additive, and the colorant and then dispersed using a high speed disperser. The mixture was then further dispersed using the Eiger mill.
- a mixture of the following composition was prepared: 20.0 g Water; 150.0 g Sodium Silicate Grade 40; and 50.0 g Hydragloss® clay.
- the sodium silicate Grade 40 was obtained from Occidental Chemical Corporation and Hydragloss® clay from J. M. Huber Corporation.
- the color pigments used in the silicate coating were Black 411A obtained from the Shepherd Company. In the sample bottle containing TIONA® 696 spray dryer discharge, 8.0 grams Black 411A was added. In the sample bottles containing TIONA® 696 finished product, Black 411A ranging from 8.0 grams to 11.0 grams were added.
- UV-VIS-NIR spectrometers from StellarNet Inc. were used to perform the reflectance measurement of the coating panels.
- the system consists of two portable spectrometers, the UV-VIS spectrometer (Model BLK-CXR-SR) for 220-1100 nm range, and the NIR spectrometer (Model RW-InGaAs-512) for 900-1700 nm range.
- the spectrometers share one 5 Watt fiber-optic light source, Tungsten Krypton, for 300-1700 nm range.
- a 50 mm diameter white reflectance standard (Model RS50) is used for reflectance intensity calibration.
- the reflectance values between 400 nm and 1700 nm are measured.
- the reflectance values for wavelengths lower than 400 nm are low and not measured due to strong absorption of light by TiO 2 in the UV wavelength range.
- a solar reflectance index was calculated from the results of the reflectance measurement of the coating panels using the method described in ASTM E1980-01.
- SRI solar radiation reference spectra data based on ASTM G173-03 are used.
- a thermal emissivity value of 0.90 and a convective coefficient of 12 were assumed.
- the reflectance measurement only the reflectance values in the range between 400 nm and 1700 nm are measured. This wavelength range does not cover the whole range of the solar spectrum.
- the solar radiation intensity in this wavelength range consists of 90.9% of the total.
- the solar intensity in 280-400 nm range and 1700-2500 nm range are 3.9% and 5.2%, respectively. Even though the SRI values are calculated based on the wavelengths between 400 nm and 1700 nm, we believe the values are meaningful for comparison between samples.
- TIONA® 696 (sometimes referred to as T-696) and RCL-6TM TiO 2 product pigment samples were measured using the optical density method.
- TIONA® 696 product pigment had a mean particle size of 0.299 ⁇ with a GSD of 1.437.
- RCL-6TM product pigment had a mean particle size of 0.319 ⁇ with a GSD of 1.492.
- Samples of the spray dryer discharge (SDD) for each product were also obtained from normal plant production. 320 grams of each spray dryer discharge sample were placed in a 2-liter plastic beaker and 400 grams of tap water were added. A high speed disperser (DISPERMAT® Model FE) with a 2′′ Cowles blade at 3000 rpm was used for the dispersion experiments.
- SDD spray dryer discharge
- the mean size and GSD of the spray dryer discharge samples were measured for different dispersing times. While the product pigment particle size measurements reflect primary particles with minimal agglomeration; the spray dryer discharge particle sizes, shown in Table 2 below, reflect the size of the titanium dioxide clusters. As can be seen, the TiO 2 clusters are quite robust and resistant to breakdown in the high speed disperser.
- Particle size distribution of TIONA®-696 and RCL-6TM spray dryer discharge samples were also measured after dispersion with media (bead) milling.
- the spray dryer discharge (SDD) samples were obtained from normal plant production. 160 grams of the spray dryer discharge sample was placed in a 0.5-liter plastic bottle and 240 grams of tap water was added. The bottle was rolled in a roller overnight. An Eiger Laboratory Mini Mill, Model M100 was used for the dispersion experiment. The volume of the milling chamber is 100 ml. The chamber was filled with 70 ml of the milling media. Ceramic media with a density of 4.3 and diameter at 2 mm was used. The resulting particle size measurements are shown in Table 3 below. Although the media mill did reduce the average cluster size somewhat, the TiO 2 clusters still appear quite robust with a GSD virtually unchanged.
- Sample 4b the above procedure for Sample 4a was repeated; except TIONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 54%, 11.62 grams black colorant paste was added. The L* value measured for the cured coating was 54.19%. From the reflectance results, the calculated SRI value is 46.42. Thus, the amount of black colorant could be cut in half.
- SDD TIONA® 696 spray dryer discharge
- Sample 5b preparation repeated that for Sample 5a white wet coil coating preparation, except RCL-6TM spray dryer discharge (SDD) was used.
- SDD spray dryer discharge
- the L* value measured for the cured coating was 53.94%.
- the measured reflectance values are shown in FIG. 2 . From the reflectance results, the calculated SRI value is 47.63.
- Sample 6b preparation repeated that for Sample 6a white wet coil coating preparation, except TiONA®-696 spray dryer discharge (SDD) was used. To reach the L* target at 54%, 13.72 grams black colorant paste was added. The L* value measured for the cured coating was 54.19%. The measured reflectance values are shown in FIG. 3 . From the reflectance results, the calculated SRI value is 47.38.
- SDD TiONA®-696 spray dryer discharge
- Sample 7b preparation repeated that for Sample 7a white wet coil coating preparation, except RCL-6TM spray dryer discharge (SDD) was used. To reach the L* target at 54%, 13.19 grams black colorant paste was added. The L* value measured for the cured coating was 54.50%. From the reflectance results, the calculated SRI value is 46.30.
- FIG. 2 shows the reflectance measurement results comparing RCL-6TM and RCL-6TM SDD with dispersion using high speed disperser only (Samples 5a and 5b).
- FIG. 3 shows the reflectance measurement results comparing TIONA®-696 and TIONA®-696 SDD with dispersion using high speed disperser and the Eiger media mill (Samples 6a and 6b). The NIR reflectance values are higher for the SDD samples.
- Sample 8b preparation repeated that for Sample 8a white wet coil coating preparation, except TiONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 64.9%, 21.75 grams blue colorant paste was added. The L* value measured for the cured coating was 64.92%. From the reflectance results, the calculated SRI value is 73.02.
- Sample 9b preparation repeated that for Sample 9a white wet coil coating preparation, except RCL-6TM spray dryer discharge (SDD) was used.
- SDD spray dryer discharge
- the L* value measured for the cured coating was 64.95%. From the reflectance results, the calculated SRI value is 73.36.
- Sample 10b preparation repeated that for Sample 10a white wet coil coating preparation, except TIONA® 696 spray dryer discharge (SDD) was used.
- SDD TIONA® 696 spray dryer discharge
- the L* value measured for the cured coating was 64.91%.
- the measured reflectance values are shown in FIG. 4 . From the reflectance results, the calculated SRI value is 72.85.
- white wet coil coating was prepared with the high speed disperser and then media milled with the Eiger mill at the grinding stage and followed by the letdown stage. Finished RCL-6TM was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 30.25 grams colorant paste made with Shepherd Blue 214 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVILTM paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 64.9%. The L* value measured for the cured coating was 64.92%. From the reflectance results, the calculated SRI value is 71.63.
- Sample 11 b preparation repeated that for Sample 11a white wet coil coating preparation, except RCL-6 spray dryer discharge (SDD) was used. To reach the L* target at 64.9%, 26.08 grams blue colorant paste was added. The L* value measured for the cured coating was 64.96%. From the reflectance results, the calculated SRI value is 71.84.
- SDD spray dryer discharge
- FIG. 4 shows the reflectance measurement results comparing TIONA®-696 and TIONA®-696 SDD with dispersion using high speed disperser and the Eiger media mill (Samples 10a and 10b). The NIR reflectance values are higher for the SDD sample.
- Sample 12b Preparation of Sample 12b repeated that for sample 12a in the white wet coil coating preparation, except TiONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 69.9%, 20.24 grams green colorant paste was added. The L* value measured for the cured coating was 69.90%. From the reflectance results, the calculated SRI value is 69.79.
- SDD TiONA® 696 spray dryer discharge
- Sample 13b Preparation of Sample 13b repeated that for Sample 13a white wet coil coating preparation, except RCL-6 spray dryer discharge (SDD) was used. To reach the L* target at 69.9%, 19.40 grams green colorant paste was added. The L* value measured for the cured coating was 69.91%. From the reflectance results, the calculated SRI value is 70.37.
- SDD spray dryer discharge
- Sample 14b Preparation of Sample 14b repeated that for Sample 14a white wet coil coating preparation, except TiONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 69.9%, 24.94 grams green colorant paste was added. The L* value measured for the cured coating was 70.02%. The measured reflectance values are shown in FIG. 5 . From the reflectance results, the calculated SRI value is 67.07.
- Sample 15b preparation repeated that for Sample 15a white wet coil coating preparation, except RCL-6TM spray dryer discharge (SDD) was used.
- SDD spray dryer discharge
- the L* value measured for the cured coating was 69.96%. From the reflectance results, the calculated SRI value is 69.45.
- FIG. 5 shows the reflectance measurement results comparing TIONA®-696 and TIONA®-696 SDD with dispersion using high speed disperser and the Eiger media mill (Samples 14a and 14b). The NIR reflectance values are higher for the SDD sample.
- Sample 16a was prepared using 44.0 grams aqueous sodium silicate and Hydragloss® clay mixture put into a 4-oz plastic bottle. 7.5 grams TiONA® 696 spray dryer discharge (SDD) sample and 8.0 grams Shepherd Black 411A colorant were added to the bottle. The content of the sample bottle was mixed over-night using a roller operated at a moderate speed. A drawdown using a 6-mil Bird drawdown bar was made on to steel panel and cured. The L* value measured for the cured coating was 41.81%. From the reflectance results, the calculated SRI value is 26.02. Sample 16b preparation repeated that for Sample 16a in the silicate coating preparation, except TiONA® 696 finished product was used. To reach the L* target at about 41.8%, 9.5 grams Shepherd Black 411A colorant was added. The L* value measured for the cured coating was 41.72%. From the reflectance results, the calculated SRI value is 25.26.
- SDD TiONA® 696 spray dryer discharge
- Comparison of Sample 16a and 16b shows that for the spray dryer discharge, the silicate coatings use 16% less Shepherd black 411A colorant to obtain the target L* value of 41.8%. Also, the SRI values are higher for the spray dryer discharge sample.
Abstract
Description
- The present application is a divisional application of U.S. application Ser. No. 14/445,636, filed Jul. 29, 2014; which is a continuation of U.S. application Ser. No. 13/253,351, filed Oct. 5, 2011, issued as U.S. Pat. No. 8,828,519 on Sep. 9, 2014. The entire contents of each of the above-referenced patent applications are hereby expressly incorporated herein by reference.
- Not applicable.
- 1. Field of Invention
- The inventive concepts disclosed and claimed herein relate generally to a coating composition and, more particularly, but not by way of limitation, to a composition having infrared-reflective clusters of titanium dioxide particles cemented together with a precipitate.
- 2. Background of the Invention
- With high energy costs and environmental concerns, there is continuing effort to reduce air conditioning requirements. An important approach for reducing air conditioning requirements is to use roofing products that reflect solar radiation. Radiation is the transfer of heat through electromagnetic energy, typically solar radiation. Absorption of radiation causes an increase in temperature at the absorbing surface and a transfer of the heat to underlying surfaces. In situations where it is desirable to reduce heating due to solar radiation, surfaces exposed to the solar radiation are treated to reflect or scatter the radiation rather than absorb it.
- Solar radiation received on the surface of the earth comprises mostly visible and near-infrared (NIR) wavelengths, with NIR consisting of more than half of the total solar radiation. Visible wavelengths are those from about 400 nm to 700 nm while NIR wavelengths are those from about 700 nm to 2500 nm. Absorption of certain visible wavelengths and reflection of the un-absorbed visible light provides color. Coatings typically include colored pigments to obtain a desired color. For example, the color blue is obtained by using blue pigment to absorb most of the non-blue visible light with wavelengths longer than 460 nm.
- Typically, black surfaces and ones having a dark color tend to absorb solar radiation causing an increase in the surface temperature. In contrast, white surfaces tend to reflect or scatter solar radiation, causing much less heating. While white surfaces offer desirable heat absorption properties, in many applications the lack of surface color is aesthetically unpleasing. Since the human eye can not see infrared light, the absorption or reflection of the infrared light by the colorants bears no consequence on the color of the coatings. Thus, a surface coating should ideally absorb only the visible radiation necessary to provide the desired color, and absorb none of the NIR radiation.
- Unfortunately, most of the conventional colorants strongly absorb infrared light. The U.S. EPA Energy Star Initiative requires that to get LEED (Leadership in Energy and Environmental Design) credit, the total solar reflectance (TSR) needs to be greater than 78% for a low sloped roof, and greater than 25% for a steep sloped roof. For the most part, products that have a TSR greater than 78% are either white or metallic, which is often not aesthetically pleasing. Darker colored roofing materials have a TSR in the 20 to 30 percent range; therefore, most dark colored residential roofs must be steep sloped. Thus there is a need for economic colorants and coating compositions that can provide high solar reflectance and reduced solar heat absorption, as well as desired color and aesthetic appearance.
- A composition is provided comprising a polymer with infrared-reflective clusters of titanium dioxide primary particles dispersed therein. The titanium dioxide primary particles are cemented together with a precipitate to form clusters. The titanium dioxide primary particles have an average particle diameter in the range of from about 0.15 to about 0.35 micron, the clusters of titanium dioxide primary particles have a geometric mass mean diameter in the range of from about 0.38 to about 5 microns, and the clusters of titanium dioxide primary particles have a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5.
- A method of reducing radiant energy absorption includes the following steps. A coating precursor is provided having therein infrared-reflective clusters of titanium dioxide primary particles. The titanium dioxide primary particles are cemented together with precipitated silica and/or alumina to form the clusters as described above. The coating precursor is then applied to a surface to form an infrared reflective coating upon drying or curing.
- In another embodiment, an infrared-reflective roofing article is provided having a base substrate with an upper surface, and a water resistant coating material covering at least a portion of the upper surface of the base substrate. The coating material includes infrared-reflective clusters of titanium dioxide primary particles. The titanium dioxide primary particles are cemented together with precipitated silica and/or alumina to form the clusters as described above.
- In yet another embodiment, a metal coil at least partially coated with a coating material comprising the above-described infrared-reflective clusters is provided. Similarly, infrared-reflective roofing granules are provided. The infrared-reflective roofing granules include base rock or mineral granules covered with a water resistant coating material comprising the above-described infrared-reflective clusters.
- In another embodiment, a method of making infrared-reflective clusters of titanium dioxide primary particles includes the following steps. An aqueous slurry of titanium dioxide particles is treated to deposit precipitated silica and/or alumina on the titanium dioxide particles. The slurry of treated titanium dioxide particles is then dried to form titanium dioxide clusters having a geometric mass mean diameter in the range of from about 0.38 to about 5 microns, while the clusters of titanium dioxide particles have a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5. The titanium dioxide clusters are packaged without micronization such that the titanium dioxide clusters retain a geometric mass mean diameter in the range of from about 0.38 to about 5 microns.
- In yet another embodiment, a method of making infrared-reflective clusters of titanium dioxide primary particles includes the following steps. An aqueous slurry of titanium dioxide particles is treated to deposit precipitated silica and/or alumina on the titanium dioxide particles. The slurry of treated titanium dioxide particles is then dried to form titanium dioxide clusters having a geometric mass mean in a range of from about 0.38 to about 5 microns, while the clusters of titanium dioxide particles have a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5. The titanium dioxide clusters are fed through a micronizing system using steam or air pressure low enough to result in product titanium dioxide clusters retaining a geometric mass mean diameter in the range of from about 0.38 to about 5 microns and a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5.
- In yet another embodiment, a method of making an infra-red reflective coating includes dispersing the infrared-reflective cluster of titanium dioxide primary particles described above into a coating formulation.
- Thus, utilizing (1) the technology known in the art; (2) the above-referenced general description of the presently claimed and disclosed inventive concept(s); and (3) the detailed description of the inventive concepts that follows, the advantages and novelties of the presently claimed and disclosed inventive concept(s) are readily apparent to one of ordinary skill in the art.
-
FIG. 1 is a graphical representation of the theoretical scattering efficiency for different particle sizes of TiO2. -
FIG. 2 is a graphical representation of the reflectance measurements comparing RCL-6™ and RCL-6™ SDD, as represented by samples 5a and 5b from Comparative Example 2. -
FIG. 3 is a graphical representation of the reflectance measurements comparing TIONA®-696 and TIONA®-696 SDD, as represented by samples 6a and 6b from Comparative Example 2. -
FIG. 4 is a graphical representation of the reflectance measurements comparing TIONA®-696 and TIONA®-696 SDD, as represented by samples 10a and 10b from Comparative Example 3. -
FIG. 5 is a graphical representation of the reflectance measurements comparing TIONA®-696 and TIONA®-696 SDD, as represented by samples 14a and 14b from Comparative Example 4. - Before explaining at least one embodiment of the presently disclosed and claimed inventive concept(s) in detail, it is to be understood that the presently disclosed and claimed inventive concept(s) is not limited in its application to the details of construction, experiments, exemplary data, and/or the arrangement of the components set forth in the following description or illustrated in the drawings. The presently disclosed and claimed inventive concept(s) is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.
- Solar radiation at sea level consists of three wavelength regions: Ultraviolet (UV), Visible, and Infrared (IR). The UV wavelengths are from 280 nm to 400 nm. The visible wavelengths are from 400 nm to 700 nm. The IR wavelengths are from 700 nm to 2500 nm. The energy of the solar radiation in each region is about 4%, 42%, and 54%, respectively, for the UV, Visible, and Infrared.
- Normal coatings are made with pigments and an organic or inorganic vehicle. The pigments are used to either absorb or reflect visible light. The vehicle is used to bind the pigments in the coating. Titanium dioxide, with high refractive indices for visible and infrared wavelengths, is an excellent material for reflecting solar radiation. In fact, normal titanium dioxide (TiO2) pigments, while designed to scatter or reflect visible light, have been found to also strongly scatter or reflect NIR light.
- From Mie theory, it is established that smaller TiO2 pigment particles are more efficient for scattering light of shorter wavelengths (e.g., blue); and larger particles are more efficient for scattering longer wavelengths (e.g., red and infrared). This has been verified by practical measurement, showing that the optimal particle size for light scattering is about one-half of the light wavelength (e.g. 0.24μ rutile TiO2 for green light at 560 nm). Referring now to
FIG. 1 , one can see the theoretical effect of TiO2 particle size on scattering efficiency in the visible and IR wavelengths. Commercial TiO2 pigment has a geometric mass mean particle size of about 0.30 micron and a geometric standard deviation (GSD) of about 1.50 such that visible light scattering efficiencies are optimized to produce a high tinting strength. However, the IR scattering efficiencies are rather weak. As the mean particle size and GSD increase, the visible scattering efficiencies decrease; however, the IR scattering efficiencies remain about the same. These light scattering calculations show that the optimal particle size of TiO2 for reflecting the maximum amount of solar infrared light is at about 0.40 micrometer (p) and higher. - However, the use of larger TiO2 particles requires a trade-off. At a particle size of 0.40μ, TiO2 also scatters significant visible light. Using TiO2 pigment with a high visible light scattering efficiency will yield good opacity or hiding power in coatings; however, it will also necessitate an increased usage of color pigments to obtain the same desired color/shade level. Color pigments absorb NIR, causing additional total heat absorption, and the color pigments used for heat-reflective applications are typically much more expensive than TiO2. Considering both the light scattering effect and economics of the more expensive color pigments, additional calculations indicate the optimum size of TiO2 particles for dark heat-reflecting coatings should be about 0.4 micron and larger.
- Unfortunately, the processing costs for making the larger diameter TiO2 pigment particles are significant. Surprisingly, however, it has been discovered that lower-cost pigment-size titanium dioxide primary particles, cemented together with precipitated silica and/or alumina to form clusters, can provide very good NIR reflection. Additionally, it was found that the TiO2 clusters do not provide the excellent visible light scattering seen with the individual particles, and thus significantly reduce the amount of colorant needed.
- Specifically, it has been found that titanium dioxide primary particles having an average particle diameter in the range of from about 0.15 to about 0.35 micron, cemented together with a precipitated silica and/or alumina to form infrared-reflective clusters having a geometric mass mean diameter in the range of from about 0.38 to about 5 microns and a geometric standard deviation (GSD) in the range of from about 1.55 to about 2.5, can be used to provide coatings with improved infrared-reflective properties. In one embodiment of the present disclosure, a coating composition includes polymer and such infrared-reflective clusters dispersed therein. The phrase “precipitated silica and/or alumina” is used herein and in the appended claims to mean that the precipitate referred to can be precipitated silica, precipitated alumina, or combinations of precipitated silica and precipitated alumina. The “precipitated silica” and the “precipitated alumina” are discussed in detail hereinafter. The term “primary particles” refers to unaggregated or unagglomerated TiO2 crystals.
- Commercial TiO2 pigment typically has a geometric mass mean particle size in the range of from about 0.2 micron to 0.36 micron and a geometric standard deviation (GSD) in the range of from about 1.40 to about 1.55. In one embodiment, the infrared-reflective clusters have a geometric mass mean diameter in the range of from about 0.38 to about 1 micron. In yet another embodiment, the infrared-reflective clusters have a geometric standard deviation (GSD) in the range of from about from 1.58 to about 2.00.
- The titanium dioxide primary particles may be treated or untreated titanium dioxide obtained directly from a production process such as the chloride or sulfate processes. Further, the TiO2 can have an anatase or rutile crystal structure. In one embodiment, the TiO2 primary particles comprise treated or untreated rutile particles produced by the chloride process. Rutile TiO2 absorbs UV light for wavelengths shorter than 405 nm while anatase TiO2 absorbs UV light for wavelengths shorter than 385 nm. While the solar UV radiation is largely absorbed and transformed to heat, since the solar radiation is between 385 nm and 400 nm represents only about 0.3% of the total solar radiation, anatase and rutile offer essentially the same heat resistance.
- While not necessary, the TiO2 primary particles can be surface treated with organic or inorganic compounds, such as precipitated oxides of phosphate, titanium, or zirconium prior to cementation with precipitated silica and/or alumina. TiO2 pigment surface treatments are known to those skilled in the art and are used to provide properties such as weatherability, durability and enhanced dispersibility in various carriers.
- The term “precipitated silica” as used herein and in the appended claims refers to any silicate; oxide, hydrous oxide, or hydroxide of silicon; and any other silicon and oxygen-containing precipitate from an aqueous soluble silica. Nonexclusive examples of aqueous soluble silica include sodium silicate and potassium silicate. The amount of precipitated silica used to cement the primary TiO2 particles together is dictated by the desired cluster size. Typically the precipitated silica is present in an amount in the range of from about 2 wt % to about 20 wt % based on the weight of titanium dioxide. In some embodiments the precipitated silica is present in the clusters in an amount in the range of from about 3 wt % to about 7 wt % based on the weight of TiO2 in the clusters.
- The term “precipitated alumina” as used herein and in the appended claims refers to any alumina; oxide, hydrous oxide, or hydroxide of aluminum; and any other alumina and oxygen-containing precipitate from an aqueous soluble alumina. Nonexclusive examples of aqueous soluble alumina include sodium aluminate and aluminum sulfate. The amount of precipitated alumina used to cement the primary TiO2 particles together is dictated by the desired cluster size. Typically the precipitated alumina is present in an amount in the range of from about 2 wt % to about 10 wt % based on the weight of titanium dioxide. In some embodiments the precipitated alumina is present in the clusters in an amount in the range of from about 3 wt % to about 5 wt % based on the weight of TiO2 in the clusters.
- A composition containing the above-described clusters can include synthetic or natural polymers and resins and can be either solvent based or water based. Examples of suitable polymers and resins include, but are not limited to, alkyds, acrylics, vinyl-acrylics, styrene acrylics, vinyl acetate/ethylene (VAE), polyvinyl acetates (PVA), polyurethanes, polyesters, polyamides, phenolics, melamine resins, epoxy, silicones and oils.
- In one embodiment, the composition includes the above-described infrared-reflective, silica and/or alumina cemented clusters of titanium dioxide and a polymer such as polyethylene, polyvinyl chloride, thermoplastic olefin, acrylonitrile butadiene styrene, or acrylonitrile-styrene-acrylic. As understood by those skilled in the art, the composition can include additional pigmentary titanium dioxide as well as colorants and other additives.
- In another embodiment, a method of reducing radiant energy absorption includes providing a coating composition precursor having dispersed therein the infrared-reflective clusters of titanium dioxide described above, and applying the coating composition precursor to a surface to form an infrared reflective coating upon drying or curing. The term “curing” is used herein to include processes involving thermosetting, catalysis, UV-curing, and other means for solidifying a coating after application. Nonlimiting examples of coating precursor compositions include paint, varnish, curable powder coatings, porcelain enamel powders, molten plastics, and the like.
- Infrared-reflective roofing articles can be prepared by application of a water resistant coating material comprising the infrared-reflective TiO2 clusters described above to at least a portion of an upper surface of a base substrate. Examples of suitable base substrates include, but are not limited to, metal coil stock as discussed above, asphalt shingles, ceramic roofing tiles, metal shakes, concrete roofing tiles, cedar shakes, natural slate roofing tiles and synthetic slate roofing tiles.
- The coating composition can be, for example, a standard paint formulation or a metal coil coating. Metal coil stock coated with the inventive compositions disclosed herein obtains much improved solar heat resistance. Infrared-reflective roofing granules are another application wherein base rock or mineral granules are coated with a water resistant coating material including the infrared-reflective TiO2 clusters described above.
- Infrared-reflective clusters of TiO2 primary particles can be made by adding any soluble silica and/or alumina to an aqueous slurry of appropriately sized TiO2 particles and causing the silica to precipitate by, for example, adjusting the pH. Such silica and alumina coating processes are practiced commercially by chloride and sulfate process titanium dioxide pigment manufacturers when making dense-silica treated pigment. Processing can include neutralization of the slurry if necessary, filtration and washing, followed by drying. For example, the pigment grades RCL-6™ and TIONA® 696 are super-durable pigments designed for outdoor use. In order to have very good durability, the pigments are treated with dense silica at about 6.5% and 3.5%, respectively. Because of the high dense silica treatments, the TiO2 particles are agglomerated together after surface treatment. Particle size measurements show that the mean cluster size of the spray dryer discharge is about 0.6 micrometers. However, commercial pigment is then deagglomerated in a fluid-energy mill such as a micronizer. Micronization is necessary to break up the clusters so that the pigment will efficiently scatter visible light. After micronization, the mean size is reduced to about 0.33 micrometer for RCL-6™ and 0.30 micrometer for TIONA® 696.
- In order to make the infrared-reflective clusters for the presently disclosed compositions, the spray dryer discharge by-passes the micronization step to maintain the necessary agglomeration and high average cluster diameter. Alternatively, the spray dryer discharge can be fed to a micronizer operated at greatly reduced steam or air pressure to produce titanium dioxide clusters having a geometric mass mean cluster diameter in the range of from about 0.38 to about 1 micron and a GSD still in the range of from about 1.55 to about 2.5. With the high dense silica treatment on the TiO2 particles, the clusters also have the high durability required for outdoor applications.
- In order to further illustrate the present invention, the following examples are given. However, it is to be understood that the examples are for illustrative purposes only and are not to be construed as limiting the scope of the invention.
- Optical Density Particle Size Measurement.
- The particle size distribution of TiO2 is measured using an optical method. The method was first described by L. W. Richards in Pigment Handbook, Vol. III, p. 89 (1973). A similar method was described by D. F. Tunsdall in the UK Patent, GB2046898 (1980). In this method, the TiO2 primary particles or clusters are dispersed in water in the form of dilute suspension. The attenuation of light by TiO2 particles or clusters in the suspension is measured using a UV-VIS spectrophotometer (Perkin-Elmer, Model 2S). The scattering efficiencies or the “optical densities” are measured as a function of the light wavelength.
- The scattering efficiency curve is normalized by setting the value equal to 1 at 440 nm. The values are compared with the normalized theoretical calculated scattering efficiency values to determine the particle size distribution of the sample. In the theoretical calculation, a log-normal distribution of the particles is assumed. A series of curves are calculated for the geometric mass mean sizes ranging from 0.200 to 1.00 micrometer and the geometric standard deviations (GSD) ranging from 1.400 to 2.400. By matching the measured curve with the theoretical curves to find the best fit, the log-normal particle size distribution of the sample, presented as mean size and GSD, can be determined. The mean size and GSD of the samples measured by the optical density method have been shown to be very similar to the values measured by electron microscope counts of about 500 to 1000 particles.
- For many particulates, the observed particle size distribution approximates a log-normal distribution. Therefore, it is often beneficial to work with particle size distributions on a logarithmic basis. The log-normal distribution is based on the normal distribution. It describes a variable, x, where log(x) is normally distributed and is valid for values of x which are greater than zero. In aerosol science, it has been observed that where the volume of a particle is proportional to size, the population is probably log-normally distributed. Thus the terms “geometric mean diameter” and “geometric standard deviation” (GSD), are substituted for “arithmetic mean diameter” and “standard deviation” when incorporating logarithms of numbers. When the frequency of the particle size distribution is based on mass, the more specific term “geometric mass mean diameter” is used.
- The spread of a log-normal distribution is controlled by the geometric standard deviation. The smaller the geometric standard deviation, the more concentrated are the data. If one adds percentages, one will see that approximately a) 68% of the distribution lies within the x between Mean/GSD and Mean*GSD; b) 95% of the distribution lies within the x between Mean/(GSD)2 and Mean*(GSD)2; and c) 99.7% of the distribution lies within the x between Mean/(GSD)3 and Mean*(GSD)3.
- Dispersion of Pigments.
- In the preparation of the wet coatings, the pigments have to be dispersed uniformly in the coating media. The dispersion process normally uses a high speed disperser, and optionally, a media (bead) mill. In the media milling process, products to be dispersed are premixed, and fed to the milling chamber with a metering pump controlling process residence time. The water-cooled milling chamber is filled with small media and agitated by a centrally located series of disks creating intense shear and impact forces. Process quality is determined by product feed rate, agitator rotational speed, grinding media type, size and loading, along with product formulation.
- The media mill used to prepare the coating samples is an Eiger Laboratory Mini Mill Model M100 made by Eiger Machinery, Inc. The volume of the milling chamber is 100 ml. The chamber is filled with 70 ml of the milling media. Ceramic media with a density of 4.3 and diameter at 2 mm is used. In operation, the agitator rotational speed is set at 3000 rpm. Samples are premixed using a high speed DISPERMAT® disperser. This disperser has a 2.5″ Cowles blade and a rotation speed of 3000 rpm is used. The premixed samples are then poured into the feed funnel with the mill operated at low rpm. With the end plate set to re-circulate, the rpm is increased to the desired level and product is allowed to circulate until the degree of product quality is achieved. Product from the feed funnel is pumped into the milling chamber and an agitated bed of grinding beads. The agitator rotational speed is electronically controlled. Product quality is determined by adjusting the chamber residence time and by adjusting the agitator rotational tip speed and the product formulation.
- Preparation of Coil Coatings.
- In order to test and compare the optical performance of the TiO2 samples in a polyester coil coating, the following test formula in Table 1 is used.
-
TABLE 1 Polyester Coil Coating Test Formula Weight (g) White Paint A. Polyester Coil Grind POLYMAC ™ 220-1935 resin 116.2 DISPERBYK ® 110 7.1 TiO2 177.6 B. Polyester Coil Letdown Grind (from A) 132.0 POLYMAC ® 220-1935 resin 76.4 CYMEL ® 303 15.1 NACURE ® 2500 1.9 Xylene 23.4 BYK ® 370 1.3 Colorant Paste Shepherd Colorant 50.0 POLYMAC ® 220-1935 resin 47.1 DISPERBYK ® 110 2.9 - POLYMAC® 220-1935 is a thermosetting polyester resin. BYK® 370 is a solution of a polyester modified hydroxy functional polydimethylsiloxane, and DISPERBYK® 110 is a dispersing additive. CYMEL® 303 is a methylated melamine-formaldehyde resin. NACURE® is a curing agent. Xylene is an organic solvent.
- The following four TiO2 samples were tested and compared: TIONA® 696 and RCL-6™ finished products (from Millennium Inorganic Chemicals) and the TIONA® 696 and RCL-6™ spray dryer discharge samples (obtained from Millennium Inorganic Chemicals). The color pigments used in the study are from the Shepherd Company. They are mixed metal oxides, including Black 411A, Blue 214, and Green 410.
- At the polyester coil grind stage, the mixture of the resin, dispersing additive, and TiO2 samples are mixed and then dispersed using a high speed disperser at 3000 rpm for 30 minutes. Four grind samples, each with a TiO2 sample, were prepared and then further prepared with the letdown stage.
- The different grind samples were first dispersed using the high speed disperser and then further dispersed using the Eiger Mill at the grind stage. The samples were further prepared with the letdown stage. After the letdown stage, the Shepherd colorant paste was added. The dispersion of the colorant paste in the coating formulation was accomplished by using the high speed disperser operated at 3500 rpm.
- The colorant paste was prepared by mixing the polyester resin, dispersing additive, and the colorant and then dispersed using a high speed disperser. The mixture was then further dispersed using the Eiger mill.
- Preparation of Silicate Coating for Roofing Granules
- A mixture of the following composition was prepared: 20.0 g Water; 150.0 g Sodium Silicate Grade 40; and 50.0 g Hydragloss® clay. The sodium silicate Grade 40 was obtained from Occidental Chemical Corporation and Hydragloss® clay from J. M. Huber Corporation.
- To prepare the coating sample, 44.0 grams well dispersed mixture from above was put into a 4-oz plastic bottle. For each sample, 7.5 grams dry TiO2 of comparative grades were added. The following two TiO2 samples were tested and compared: TIONA® 696 finished product and the TIONA® 696 spray dryer discharge sample.
- The color pigments used in the silicate coating were Black 411A obtained from the Shepherd Company. In the sample bottle containing TIONA® 696 spray dryer discharge, 8.0 grams Black 411A was added. In the sample bottles containing TIONA® 696 finished product, Black 411A ranging from 8.0 grams to 11.0 grams were added.
- Reflectance Measurements.
- UV-VIS-NIR spectrometers from StellarNet Inc. were used to perform the reflectance measurement of the coating panels. The system consists of two portable spectrometers, the UV-VIS spectrometer (Model BLK-CXR-SR) for 220-1100 nm range, and the NIR spectrometer (Model RW-InGaAs-512) for 900-1700 nm range. The spectrometers share one 5 Watt fiber-optic light source, Tungsten Krypton, for 300-1700 nm range.
- A 50 mm diameter white reflectance standard (Model RS50) is used for reflectance intensity calibration. In the spectral reflectance measurement, the reflectance values between 400 nm and 1700 nm are measured. The reflectance values for wavelengths lower than 400 nm are low and not measured due to strong absorption of light by TiO2 in the UV wavelength range.
- Solar Reflectance Index Calculations.
- A solar reflectance index (SRI) was calculated from the results of the reflectance measurement of the coating panels using the method described in ASTM E1980-01. To calculate SRI, the solar radiation reference spectra data based on ASTM G173-03 are used. To perform the calculation, a thermal emissivity value of 0.90 and a convective coefficient of 12 were assumed.
- In the reflectance measurement, only the reflectance values in the range between 400 nm and 1700 nm are measured. This wavelength range does not cover the whole range of the solar spectrum. The solar radiation intensity in this wavelength range consists of 90.9% of the total. The solar intensity in 280-400 nm range and 1700-2500 nm range are 3.9% and 5.2%, respectively. Even though the SRI values are calculated based on the wavelengths between 400 nm and 1700 nm, we believe the values are meaningful for comparison between samples.
- The optical density particle size distributions of finished TIONA® 696 (sometimes referred to as T-696) and RCL-6™ TiO2 product pigment samples were measured using the optical density method. TIONA® 696 product pigment had a mean particle size of 0.299μ with a GSD of 1.437. RCL-6™ product pigment had a mean particle size of 0.319μ with a GSD of 1.492. Samples of the spray dryer discharge (SDD) for each product were also obtained from normal plant production. 320 grams of each spray dryer discharge sample were placed in a 2-liter plastic beaker and 400 grams of tap water were added. A high speed disperser (DISPERMAT® Model FE) with a 2″ Cowles blade at 3000 rpm was used for the dispersion experiments. The mean size and GSD of the spray dryer discharge samples were measured for different dispersing times. While the product pigment particle size measurements reflect primary particles with minimal agglomeration; the spray dryer discharge particle sizes, shown in Table 2 below, reflect the size of the titanium dioxide clusters. As can be seen, the TiO2 clusters are quite robust and resistant to breakdown in the high speed disperser.
-
TABLE 2 Cluster Size Measurements with Dispersion Sample ID and Disp. Time Mean Size, μ GSD TIONA ®-696 SDD @ 0 min 0.598 1.61 TIONA ®-696 SDD @ 15 min 0.564 1.62 TIONA ®-696 SDD @ 30 min 0.554 1.61 TIONA ®-696 SDD @ 60 min 0.538 1.60 RCL-6 ™ SDD @ 0 min 0.622 1.64 RCL-6 ™ SDD @ 15 min 0.598 1.62 RCL-6 ™ SDD @ 30 min 0.592 1.62 RCL-6 ™ SDD @ 60 min 0.592 1.60 - Particle size distribution of TIONA®-696 and RCL-6™ spray dryer discharge samples were also measured after dispersion with media (bead) milling. Again, the spray dryer discharge (SDD) samples were obtained from normal plant production. 160 grams of the spray dryer discharge sample was placed in a 0.5-liter plastic bottle and 240 grams of tap water was added. The bottle was rolled in a roller overnight. An Eiger Laboratory Mini Mill, Model M100 was used for the dispersion experiment. The volume of the milling chamber is 100 ml. The chamber was filled with 70 ml of the milling media. Ceramic media with a density of 4.3 and diameter at 2 mm was used. The resulting particle size measurements are shown in Table 3 below. Although the media mill did reduce the average cluster size somewhat, the TiO2 clusters still appear quite robust with a GSD virtually unchanged.
-
TABLE 3 Cluster Size Measurements after Milling Sample ID and Milling Time Mean Size, μ GSD TIONA ®-696 SDD @ 0 min 0.578 1.60 TIONA ®-696 SDD @ 15 min 0.480 1.64 TIONA ®-696 SDD @ 30 min 0.446 1.62 TIONA ®-696 SDD @ 60 min 0.428 1.61 RCL-6 ™ SDD @ 0 min 0.614 1.63 RCL-6 ™ SDD @ 15 min 0.462 1.62 RCL-6 ™ SDD @ 30 min 0.428 1.59 RCL-6 ™ SDD @ 60 min 0.436 1.60 - The following samples were compared for reflectance properties in a coil coating using Shepherd Black 411A Colorant. For Sample 4a, white wet coil coating was prepared with the high speed disperser only at the grinding stage and followed by the letdown stage. Finished TIONA® 696 was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 22.52 grams colorant paste made with Shepherd Black 411A was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made onto an aluminum panel and cured. The amount of colorant paste used was to target the L* at 54%. The L* value measured for the cured coating was 54.12%. From the reflectance results, the calculated SRI value is 44.07.
- For Sample 4b, the above procedure for Sample 4a was repeated; except TIONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 54%, 11.62 grams black colorant paste was added. The L* value measured for the cured coating was 54.19%. From the reflectance results, the calculated SRI value is 46.42. Thus, the amount of black colorant could be cut in half.
- For Sample 5a, white wet coil coating was prepared with the high speed disperser only at the grinding stage and followed by the letdown stage. Finished RCL-6™ was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 18.88 grams colorant paste, made with Shepherd Black 411A, was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made onto an aluminum panel and cured. The amount of colorant paste used was to target the L* at 54%. The L* value measured for the cured coating was 53.98%. The measured reflectance values are shown in
FIG. 2 . From the reflectance results, the calculated SRI value is 43.63. - Sample 5b preparation repeated that for Sample 5a white wet coil coating preparation, except RCL-6™ spray dryer discharge (SDD) was used. To reach the L* target at 54%, 10.04 grams black colorant paste was added. The L* value measured for the cured coating was 53.94%. The measured reflectance values are shown in
FIG. 2 . From the reflectance results, the calculated SRI value is 47.63. - For Sample 6a, white wet coil coating was prepared with the high speed disperser and then media milled with the Eiger mill at the grinding stage and followed by the letdown stage. Finished TiONA® 696 was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 23.05 grams colorant paste made with Shepherd Black 411A was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 54%. The L* value measured for the cured coating was 54.16%. The measured reflectance values are shown in
FIG. 3 . From the reflectance results, the calculated SRI value is 42.88. - Sample 6b preparation repeated that for Sample 6a white wet coil coating preparation, except TiONA®-696 spray dryer discharge (SDD) was used. To reach the L* target at 54%, 13.72 grams black colorant paste was added. The L* value measured for the cured coating was 54.19%. The measured reflectance values are shown in
FIG. 3 . From the reflectance results, the calculated SRI value is 47.38. - For Sample 7a, white wet coil coating was prepared with the high speed disperser and then media milled with the Eiger mill at the grinding stage followed by the letdown stage. Finished RCL-6™ was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 18.96 grams colorant paste made with Shepherd Black 411A was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 54%. The L* value measured for the cured coating was 54.34%. From the reflectance results, the calculated SRI value is 44.96.
- Sample 7b preparation repeated that for Sample 7a white wet coil coating preparation, except RCL-6™ spray dryer discharge (SDD) was used. To reach the L* target at 54%, 13.19 grams black colorant paste was added. The L* value measured for the cured coating was 54.50%. From the reflectance results, the calculated SRI value is 46.30.
- The results for Samples 4a through 7b are summarized in Table 4. Comparing the finished product and the spray dryer discharge samples of TIONA®-696 and RCL-6™, the results consistently show that for the spray dryer discharge samples, the coatings use considerably less Shepherd black colorant 411A to obtain the target L* value of 54%. Also, the SRI values are higher for the spray dryer discharge samples.
FIG. 2 shows the reflectance measurement results comparing RCL-6™ and RCL-6™ SDD with dispersion using high speed disperser only (Samples 5a and 5b).FIG. 3 shows the reflectance measurement results comparing TIONA®-696 and TIONA®-696 SDD with dispersion using high speed disperser and the Eiger media mill (Samples 6a and 6b). The NIR reflectance values are higher for the SDD samples. -
TABLE 4 Summary Results for Comparative Example 2 Using Black 411A Colorant Paint Tint Sample TiO2 Dispersion (g) (g) L* SRI 4a TIONA ® 696 HSD 100.00 22.52 54.12 44.07 4b TIONA ® 696 HSD 100.00 11.62 54.19 46.42 SDD 5a RCL-6 ™ HSD 100.00 18.88 53.98 43.63 5b RCL-6 ™ SDD HSD 100.00 10.04 53.94 47.63 6a TIONA ® 696 HSD + MM 100.00 23.05 54.16 42.88 6b TIONA ® 696 HSD + MM 100.00 13.72 54.19 47.38 SDD 7a RCL-6 ™ HSD + MM 100.00 18.96 54.34 44.96 7b RCL-6 ™ SDD HSD + MM 100.00 13.19 54.50 46.30 - The following samples were compared for reflectance properties in a coil coating using Shepherd Blue 214 Colorant. For Sample 8a, white wet coil coating was prepared with the high speed disperser only at the grinding stage and followed by the letdown stage. Finished TiONA® 696 was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 32.22 grams colorant paste made with Shepherd Blue 214 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL® paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 64.9%. The L* value measured for the cured coating was 64.99%. From the reflectance results, the calculated SRI value is 69.80.
- Sample 8b preparation repeated that for Sample 8a white wet coil coating preparation, except TiONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 64.9%, 21.75 grams blue colorant paste was added. The L* value measured for the cured coating was 64.92%. From the reflectance results, the calculated SRI value is 73.02.
- For Sample 9a, white wet coil coating was prepared with the high speed disperser only at the grinding stage and followed by the letdown stage. Finished RCL-6™ was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 30.23 grams colorant paste made with Shepherd Blue 214 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 64.9%. The L* value measured for the cured coating was 64.90%. From the reflectance results, the calculated SRI value is 71.38.
- Sample 9b preparation repeated that for Sample 9a white wet coil coating preparation, except RCL-6™ spray dryer discharge (SDD) was used. To reach the L* target at 64.9%, 20.65 grams blue colorant paste was added. The L* value measured for the cured coating was 64.95%. From the reflectance results, the calculated SRI value is 73.36.
- For Sample 10a, white wet coil coating was prepared with the high speed disperser and then media milled with the Eiger mill at the grinding stage and followed by the letdown stage. Finished TiONA 696 was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 32.93 grams colorant paste made with Shepherd Blue 214 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 64.9%. The L* value measured for the cured coating was 64.77%. The measured reflectance values are shown in
FIG. 4 . From the reflectance results, the calculated SRI value is 69.48. - Sample 10b preparation repeated that for Sample 10a white wet coil coating preparation, except TIONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 64.9%, 26.11 grams blue colorant paste was added. The L* value measured for the cured coating was 64.91%. The measured reflectance values are shown in
FIG. 4 . From the reflectance results, the calculated SRI value is 72.85. - For Sample 11a, white wet coil coating was prepared with the high speed disperser and then media milled with the Eiger mill at the grinding stage and followed by the letdown stage. Finished RCL-6™ was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 30.25 grams colorant paste made with Shepherd Blue 214 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 64.9%. The L* value measured for the cured coating was 64.92%. From the reflectance results, the calculated SRI value is 71.63.
- Sample 11 b preparation repeated that for Sample 11a white wet coil coating preparation, except RCL-6 spray dryer discharge (SDD) was used. To reach the L* target at 64.9%, 26.08 grams blue colorant paste was added. The L* value measured for the cured coating was 64.96%. From the reflectance results, the calculated SRI value is 71.84.
- The results for Samples 8a through 11b are summarized in Table 5. Comparing the finished product and the spray dryer discharge samples of TIONA® 696 and RCL6™, the results consistently show that for the spray dryer discharge samples, the coatings use considerably less Shepherd blue colorant 214 to obtain the target L* value of 64.9%. Also, the SRI values are higher for the spray dryer discharge samples.
FIG. 4 shows the reflectance measurement results comparing TIONA®-696 and TIONA®-696 SDD with dispersion using high speed disperser and the Eiger media mill (Samples 10a and 10b). The NIR reflectance values are higher for the SDD sample. -
TABLE 5 Summary Results for Comparative Example 3 Using Blue 214 Colorant Paint Tint Sample TiO2 Dispersion (g) (g) L* SRI 8a TIONA ® 696 HSD 100.00 32.22 64.99 69.80 8b TIONA ® 696 HSD 100.00 21.75 64.92 73.02 SDD 9a RCL6 ™ HSD 100.00 30.23 64.90 71.38 9b RCL6 ™ SDD HSD 100.00 20.65 64.95 73.36 10a TIONA ® 696 HSD + MM 100.00 32.93 64.77 69.48 10b TIONA ® 696 HSD + MM 100.00 26.11 64.91 72.85 SDD 11a RCL6 ™ HSD + MM 100.00 30.25 64.92 71.63 11b RCL6 ™ SDD HSD + MM 100.00 26.08 64.96 71.84 - The following samples were compared for reflectance properties in a coil coating using Shepherd Green 410 Colorant. For Sample 12a, white wet coil coating was prepared with the high speed disperser only at the grinding stage and followed by the letdown stage. Finished TiONA® 696 was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 32.48 grams colorant paste made with Shepherd Green 410 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 69.9%. The L* value measured for the cured coating was 69.97%. From the reflectance results, the calculated SRI value is 67.00.
- Preparation of Sample 12b repeated that for sample 12a in the white wet coil coating preparation, except TiONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 69.9%, 20.24 grams green colorant paste was added. The L* value measured for the cured coating was 69.90%. From the reflectance results, the calculated SRI value is 69.79.
- For preparation of Sample 13a, white wet coil coating was prepared with the high speed disperser only at the grinding stage and followed by the letdown stage. Finished RCL-6™ was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 31.18 grams colorant paste made with Shepherd Green 410 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 69.9%. The L* value measured for the cured coating was 69.91%. From the reflectance results, the calculated SRI value is 67.13.
- Preparation of Sample 13b repeated that for Sample 13a white wet coil coating preparation, except RCL-6 spray dryer discharge (SDD) was used. To reach the L* target at 69.9%, 19.40 grams green colorant paste was added. The L* value measured for the cured coating was 69.91%. From the reflectance results, the calculated SRI value is 70.37.
- For preparation of Sample 14a, white wet coil coating was prepared with the high speed disperser and then media milled with the Eiger mill at the grinding stage and followed by the letdown stage. Finished TiONA 696 was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 33.20 grams colorant paste made with Shepherd Green 410 was added to the can. The content in the paint can was agitated for 10 minutes using a Red-Devil paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 69.9%. The L* value measured for the cured coating was 69.84%. The measured reflectance values are shown in
FIG. 5 . From the reflectance results, the calculated SRI value is 66.40. - Preparation of Sample 14b repeated that for Sample 14a white wet coil coating preparation, except TiONA® 696 spray dryer discharge (SDD) was used. To reach the L* target at 69.9%, 24.94 grams green colorant paste was added. The L* value measured for the cured coating was 70.02%. The measured reflectance values are shown in
FIG. 5 . From the reflectance results, the calculated SRI value is 67.07. - For Sample 15a, white wet coil coating was prepared with the high speed disperser and then media milled with the Eiger mill at the grinding stage and followed by the letdown stage. Finished RCL-6™ was used as TiO2 pigment. 100 grams of white coating was placed in an 8 oz metal paint can. 31.44 grams colorant paste made with Shepherd Green 410 was added to the can. The content in the paint can was agitated for 10 minutes using a RED-DEVIL™ paint shaker. A drawdown using #28 wire-wound rod was made on to an aluminum panel and cured. The amount of colorant paste used was to target the L* at 69.9%. The L* value measured for the cured coating was 69.90%. From the reflectance results, the calculated SRI value is 64.54.
- Sample 15b preparation repeated that for Sample 15a white wet coil coating preparation, except RCL-6™ spray dryer discharge (SDD) was used. To reach the L* target at 69.9%, 24.95 grams green colorant paste was added. The L* value measured for the cured coating was 69.96%. From the reflectance results, the calculated SRI value is 69.45.
- The results for Samples 12a through 15b are summarized in Table 6. The results consistently show that the coatings using spray dryer discharge rather than finished pigment required considerably less Shepherd Green colorant 410 to obtain the target L* value of 69.9%. Also, the SRI values are higher for the spray dryer discharge samples.
FIG. 5 shows the reflectance measurement results comparing TIONA®-696 and TIONA®-696 SDD with dispersion using high speed disperser and the Eiger media mill (Samples 14a and 14b). The NIR reflectance values are higher for the SDD sample. -
TABLE 6 Summary Results for Comparative Example 4 Using Green 410 Colorant Paint Sample TiO2 Dispersion (g) Tint (g) L* SRI 12a TIONA ® 696 HSD 100.00 32.48 69.97 67.00 12b TIONA ® 696 HSD 100.00 20.24 69.90 69.79 SDD 13a RCL6 ™ HSD 100.00 31.18 69.91 67.13 13b RCL6 ™ SDD HSD 100.00 19.40 69.91 70.37 14a TIONA ® 696 HSD + MM 100.00 33.20 69.84 66.40 14b TIONA ® 696 HSD + MM 100.00 24.94 70.02 67.07 SDD 15a RCL6 ™ HSD + MM 100.00 31.44 69.90 64.54 15b RCL6 ™ SDD HSD + MM 100.00 24.95 69.96 69.45 - The following samples were compared for reflectance properties in a silicate coating. Sample 16a was prepared using 44.0 grams aqueous sodium silicate and Hydragloss® clay mixture put into a 4-oz plastic bottle. 7.5 grams TiONA® 696 spray dryer discharge (SDD) sample and 8.0 grams Shepherd Black 411A colorant were added to the bottle. The content of the sample bottle was mixed over-night using a roller operated at a moderate speed. A drawdown using a 6-mil Bird drawdown bar was made on to steel panel and cured. The L* value measured for the cured coating was 41.81%. From the reflectance results, the calculated SRI value is 26.02. Sample 16b preparation repeated that for Sample 16a in the silicate coating preparation, except TiONA® 696 finished product was used. To reach the L* target at about 41.8%, 9.5 grams Shepherd Black 411A colorant was added. The L* value measured for the cured coating was 41.72%. From the reflectance results, the calculated SRI value is 25.26.
- Comparison of Sample 16a and 16b shows that for the spray dryer discharge, the silicate coatings use 16% less Shepherd black 411A colorant to obtain the target L* value of 41.8%. Also, the SRI values are higher for the spray dryer discharge sample.
- From the above examples and descriptions, it is clear that the present inventive process(es), methodology(ies), apparatus(es) and composition(s) are well adapted to carry out the objects and to attain the advantages mentioned herein, as well as those inherent in the presently provided disclosure. While presently preferred embodiments of the invention have been described for purposes of this disclosure, it will be understood that numerous changes may be made which will readily suggest themselves to those skilled in the art and which are accomplished within the spirit of the presently claimed and disclosed inventive process(es), methodology(ies), apparatus(es) and composition(s) described herein.
Claims (13)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US14/855,868 US20160002474A1 (en) | 2011-10-05 | 2015-09-16 | Infrared-reflective coatings |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/253,351 US8828519B2 (en) | 2011-10-05 | 2011-10-05 | Infrared-reflective coatings |
US14/445,636 US20140366775A1 (en) | 2011-10-05 | 2014-07-29 | Infrared-reflective coatings |
US14/855,868 US20160002474A1 (en) | 2011-10-05 | 2015-09-16 | Infrared-reflective coatings |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/445,636 Division US20140366775A1 (en) | 2011-10-05 | 2014-07-29 | Infrared-reflective coatings |
Publications (1)
Publication Number | Publication Date |
---|---|
US20160002474A1 true US20160002474A1 (en) | 2016-01-07 |
Family
ID=48042273
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/253,351 Active 2032-04-03 US8828519B2 (en) | 2011-10-05 | 2011-10-05 | Infrared-reflective coatings |
US14/445,636 Abandoned US20140366775A1 (en) | 2011-10-05 | 2014-07-29 | Infrared-reflective coatings |
US14/855,868 Abandoned US20160002474A1 (en) | 2011-10-05 | 2015-09-16 | Infrared-reflective coatings |
Family Applications Before (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/253,351 Active 2032-04-03 US8828519B2 (en) | 2011-10-05 | 2011-10-05 | Infrared-reflective coatings |
US14/445,636 Abandoned US20140366775A1 (en) | 2011-10-05 | 2014-07-29 | Infrared-reflective coatings |
Country Status (8)
Country | Link |
---|---|
US (3) | US8828519B2 (en) |
EP (1) | EP2764061B1 (en) |
CN (1) | CN104024343B (en) |
AU (1) | AU2012333063B2 (en) |
CA (1) | CA2850372C (en) |
MX (1) | MX353622B (en) |
TW (1) | TWI506072B (en) |
WO (1) | WO2013066545A2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107057494A (en) * | 2017-03-29 | 2017-08-18 | 合肥天沃能源科技有限公司 | A kind of scratch-resistant thermal insulation coatings and preparation method thereof |
US10584494B2 (en) | 2017-04-26 | 2020-03-10 | Owens Corning Intellectual Capital, Llc | Asphalt based roofing material with increased infrared reflectivity |
WO2023164461A1 (en) * | 2022-02-25 | 2023-08-31 | Eagle Eye Research, Inc. | Ultra-cool and thermochromic roof and siding coatings |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR3017873A1 (en) * | 2014-02-27 | 2015-08-28 | Baikowski | SUSPENSION FOR REFLECTIVE COATING OF LIGHTING DEVICE AND METHOD OF MANUFACTURING THE SAME |
US9329647B2 (en) | 2014-05-19 | 2016-05-03 | Microsoft Technology Licensing, Llc | Computing device having a spectrally selective radiation emission device |
ES2647225T3 (en) * | 2014-07-11 | 2017-12-20 | Dow Global Technologies Llc | Transparent reflective infrared coating compositions for elastomeric wall and wall coverings |
CN104194624A (en) * | 2014-09-18 | 2014-12-10 | 山东大学 | Yellow near-infrared high reflective coating and preparation method thereof |
CN104194539B (en) * | 2014-09-28 | 2016-04-20 | 芜湖县双宝建材有限公司 | A kind of high adhesive force stamping enamel |
WO2016099466A1 (en) * | 2014-12-16 | 2016-06-23 | Boral Ip Holdings (Australia) Pty Limited | Reflective coating films and methods of making and using the same |
CN104877570A (en) * | 2015-05-26 | 2015-09-02 | 柳州市亿廷贸易有限责任公司 | Preparation method of water-resistant paint |
CN104987134B (en) * | 2015-07-29 | 2017-04-12 | 长安大学 | Method for preparing nickel coating on ceramic surface by using in-situ reduction method |
US11163132B2 (en) * | 2016-04-18 | 2021-11-02 | Canon Kabushiki Kaisha | Thermal barrier film, thermal barrier paint, and optical instrument |
DK178890B1 (en) * | 2016-06-13 | 2017-05-01 | Ars Holding Kolding As | IR reflective surface treatment |
NL2019318B1 (en) | 2017-07-21 | 2019-01-30 | Tno | Photovoltaic module |
CN108912572B (en) * | 2018-08-21 | 2021-03-02 | 哈尔滨工业大学(威海) | Radiation-induced cooling film with self-cleaning function and preparation method thereof |
CN110016193B (en) * | 2019-04-30 | 2021-02-19 | 山东飞鹰新型防水材料有限公司 | Self-cleaning PVC waterproof roll capable of being cooled and preparation method thereof |
CN113861783B (en) * | 2021-10-27 | 2022-06-17 | 重庆重交再生资源开发股份有限公司 | Composition for regulating temperature of asphalt pavement and preparation method and application thereof |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6174360B1 (en) * | 1998-10-26 | 2001-01-16 | Ferro Corporation | Infrared reflective color pigment |
US6521038B2 (en) * | 2000-12-21 | 2003-02-18 | Dainichiseika Color & Chemicals Mfg. Co., Ltd. | Near-infrared reflecting composite pigments |
US6783586B2 (en) * | 2001-11-01 | 2004-08-31 | E. I. Du Pont De Nemours And Company | Easy to disperse, high durability TiO2 pigment and method of making same |
US20050072114A1 (en) * | 2003-10-06 | 2005-04-07 | Shiao Ming Liang | Colored roofing granules with increased solar heat reflectance, solar heat-reflective shingles, and process for producing same |
JP2009242768A (en) * | 2008-02-29 | 2009-10-22 | Admatechs Co Ltd | Light ray reflective coating material and manufacturing method thereof |
US20110008622A1 (en) * | 2008-03-31 | 2011-01-13 | Kalkanoglu Husnu M | Coating compositions for roofing granules, dark colored roofing granules with increased solar heat reflectance, solar heat-reflective shingles, and process for producing the same |
CN102015915A (en) * | 2008-05-07 | 2011-04-13 | 钛白粉欧洲有限公司 | Titanium dioxide |
GB2477930A (en) * | 2010-02-17 | 2011-08-24 | Tioxide Europe Ltd | Solar reflective system |
US8506768B2 (en) * | 2007-09-14 | 2013-08-13 | Cardinal Cg Company | Low-maintenance coatings, and methods for producing low-maintenance coatings |
Family Cites Families (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL235038A (en) * | 1958-01-15 | 1900-01-01 | ||
US3437502A (en) * | 1968-03-28 | 1969-04-08 | Du Pont | Titanium dioxide pigment coated with silica and alumina |
GB2046898B (en) * | 1979-03-21 | 1983-01-26 | Tioxide Group Ltd | Method of measurement of particles |
CN1131691A (en) * | 1995-03-22 | 1996-09-25 | 万启洪 | Infrared radiation paint and its usage |
US5653793A (en) * | 1995-08-01 | 1997-08-05 | E. I. Du Pont De Nemours And Company | TiO2 slurry process |
US5898180A (en) | 1997-05-23 | 1999-04-27 | General Electric Company | Infrared energy reflecting composition and method of manufacture |
CN1074025C (en) * | 1998-06-05 | 2001-10-31 | 深圳市金岁丰实业有限公司 | Coating capable of reflecting sun-heat |
CN1363636A (en) * | 2001-01-02 | 2002-08-14 | 顾晓鸣 | Energy-saving ultraviolet and infrared resistant paint |
EP1468737A4 (en) * | 2002-01-21 | 2005-09-21 | Sumitomo Titanium Corp | Photocatalytic composite material and method for preparation thereof |
JP4546834B2 (en) | 2002-12-09 | 2010-09-22 | テイカ株式会社 | Titanium oxide particles having beneficial properties and method for producing the same |
JP4145923B2 (en) * | 2003-01-09 | 2008-09-03 | 株式会社フジクラ | Titanium oxide particles, manufacturing method thereof, manufacturing apparatus, and processing method using the titanium oxide |
US7452598B2 (en) | 2003-10-06 | 2008-11-18 | Certainteed Corporation | Mineral-surfaced roofing shingles with increased solar heat reflectance, and process for producing same |
FR2874607B1 (en) | 2004-08-31 | 2008-05-02 | Saint Gobain | LAMINATED GLAZING WITH A STACK OF THIN LAYERS REFLECTING INFRARED AND / OR SOLAR RADIATION AND A HEATING MEANS. |
US7261770B2 (en) | 2004-11-24 | 2007-08-28 | Millennium Inorganic Chemicals, Inc. | Compositions and methods comprising pigments and polyprotic dispersing agents |
US20070028806A1 (en) * | 2005-08-03 | 2007-02-08 | Piro Bonnie D | Coating compositions having improved appearance containing coated titanium dioxide pigments |
KR20070024285A (en) | 2005-08-26 | 2007-03-02 | 삼성에스디아이 주식회사 | Laser induced thermal imaging donor film, organic light emitting diode display using thereof and fabricating method the same |
US7641959B2 (en) | 2005-09-16 | 2010-01-05 | Isp Investments Inc. | Roofing granules of enhanced solar reflectance |
US7592066B2 (en) | 2005-10-05 | 2009-09-22 | Certainteed Corporation | Roofing articles with reflective thin films and the process of producing the same |
US7250080B1 (en) | 2006-09-06 | 2007-07-31 | Tronox Llc | Process for the manufacture of organosilicon compound-treated pigments |
JP4880410B2 (en) * | 2006-09-28 | 2012-02-22 | 多木化学株式会社 | Member coated with photocatalytic coating composition |
EP2104555A4 (en) * | 2006-12-22 | 2012-09-19 | 3M Innovative Properties Co | Photocatalytic coating |
JP2008230964A (en) * | 2008-04-03 | 2008-10-02 | Ishihara Sangyo Kaisha Ltd | Strong cohesive titanium oxide |
CN101280128B (en) * | 2008-06-02 | 2011-08-17 | 深圳职业技术学院 | Anatase titanium dioxide type titanium white pulp and preparation thereof |
US20100307553A1 (en) | 2008-08-26 | 2010-12-09 | Defries Anthony | Engineering light manipulation in structured films or coatings |
US20100104809A1 (en) | 2008-10-27 | 2010-04-29 | Duda Joseph F | Cool roof covering |
US8394498B2 (en) | 2008-12-16 | 2013-03-12 | Certainteed Corporation | Roofing granules with high solar reflectance, roofing materials with high solar reflectance, and the process of making the same |
CN105708729A (en) * | 2009-10-12 | 2016-06-29 | 欧莱雅 | Methods of photoprotecting a material against solar uv radiation using photonic particles; compositions |
-
2011
- 2011-10-05 US US13/253,351 patent/US8828519B2/en active Active
-
2012
- 2012-10-01 CA CA2850372A patent/CA2850372C/en active Active
- 2012-10-01 MX MX2014003922A patent/MX353622B/en active IP Right Grant
- 2012-10-01 EP EP12845793.4A patent/EP2764061B1/en active Active
- 2012-10-01 WO PCT/US2012/058322 patent/WO2013066545A2/en active Application Filing
- 2012-10-01 AU AU2012333063A patent/AU2012333063B2/en not_active Ceased
- 2012-10-01 CN CN201280052189.8A patent/CN104024343B/en active Active
- 2012-10-05 TW TW101136992A patent/TWI506072B/en active
-
2014
- 2014-07-29 US US14/445,636 patent/US20140366775A1/en not_active Abandoned
-
2015
- 2015-09-16 US US14/855,868 patent/US20160002474A1/en not_active Abandoned
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6174360B1 (en) * | 1998-10-26 | 2001-01-16 | Ferro Corporation | Infrared reflective color pigment |
US6521038B2 (en) * | 2000-12-21 | 2003-02-18 | Dainichiseika Color & Chemicals Mfg. Co., Ltd. | Near-infrared reflecting composite pigments |
US6783586B2 (en) * | 2001-11-01 | 2004-08-31 | E. I. Du Pont De Nemours And Company | Easy to disperse, high durability TiO2 pigment and method of making same |
US20050072114A1 (en) * | 2003-10-06 | 2005-04-07 | Shiao Ming Liang | Colored roofing granules with increased solar heat reflectance, solar heat-reflective shingles, and process for producing same |
US8506768B2 (en) * | 2007-09-14 | 2013-08-13 | Cardinal Cg Company | Low-maintenance coatings, and methods for producing low-maintenance coatings |
JP2009242768A (en) * | 2008-02-29 | 2009-10-22 | Admatechs Co Ltd | Light ray reflective coating material and manufacturing method thereof |
US20110008622A1 (en) * | 2008-03-31 | 2011-01-13 | Kalkanoglu Husnu M | Coating compositions for roofing granules, dark colored roofing granules with increased solar heat reflectance, solar heat-reflective shingles, and process for producing the same |
CN102015915A (en) * | 2008-05-07 | 2011-04-13 | 钛白粉欧洲有限公司 | Titanium dioxide |
GB2477930A (en) * | 2010-02-17 | 2011-08-24 | Tioxide Europe Ltd | Solar reflective system |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107057494A (en) * | 2017-03-29 | 2017-08-18 | 合肥天沃能源科技有限公司 | A kind of scratch-resistant thermal insulation coatings and preparation method thereof |
US10584494B2 (en) | 2017-04-26 | 2020-03-10 | Owens Corning Intellectual Capital, Llc | Asphalt based roofing material with increased infrared reflectivity |
WO2023164461A1 (en) * | 2022-02-25 | 2023-08-31 | Eagle Eye Research, Inc. | Ultra-cool and thermochromic roof and siding coatings |
Also Published As
Publication number | Publication date |
---|---|
US20130089706A1 (en) | 2013-04-11 |
CA2850372C (en) | 2016-08-16 |
EP2764061A2 (en) | 2014-08-13 |
TWI506072B (en) | 2015-11-01 |
AU2012333063A8 (en) | 2015-09-10 |
TW201329142A (en) | 2013-07-16 |
MX2014003922A (en) | 2014-04-30 |
US20140366775A1 (en) | 2014-12-18 |
US8828519B2 (en) | 2014-09-09 |
AU2012333063A1 (en) | 2014-04-17 |
EP2764061A4 (en) | 2015-05-06 |
CA2850372A1 (en) | 2013-05-10 |
WO2013066545A3 (en) | 2013-08-08 |
CN104024343A (en) | 2014-09-03 |
AU2012333063B2 (en) | 2016-04-21 |
WO2013066545A2 (en) | 2013-05-10 |
CN104024343B (en) | 2017-08-08 |
EP2764061B1 (en) | 2022-11-30 |
MX353622B (en) | 2018-01-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8828519B2 (en) | Infrared-reflective coatings | |
JP6199538B2 (en) | titanium dioxide | |
KR101867266B1 (en) | Titanium dioxide | |
CA2849773A1 (en) | Treated inorganic core particles having improved dispersability | |
US20150329737A1 (en) | Titanium dioxide | |
US7824487B2 (en) | Rutile-based pigment and a method for the production thereof | |
TW201805370A (en) | A method for treating titanium dioxide particles, a titanium dioxide particle and uses of the same | |
JP7086867B2 (en) | Titanium dioxide product |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: MILLENNIUM INORGANIC CHEMICALS, INC., MARYLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WEN, FU-CHU;BUSCH, DEBORAH E.;FRICKER, RICHARD L.;AND OTHERS;REEL/FRAME:036579/0742 Effective date: 20110928 Owner name: CRISTAL USA INC., MARYLAND Free format text: CHANGE OF NAME;ASSIGNOR:MILLENNIUM INORGANIC CHEMICALS, INC.;REEL/FRAME:036619/0185 Effective date: 20120927 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |