Patent Publication Number: US-2006009565-A1

Title: Phosphorescent pigment mixtures and dispersions

Description:
RELATED MATTERS  
      The present application claims priority to and is a Continuation-In Part of U.S. application Ser. No. 10/723,017, filed on Nov. 26, 2003, and entitled “Methods for Coating Substrate,” the disclosure of which is incorporated by reference herein. 
    
    
     FIELD  
      The invention relates generally to phosphorescent pigments and more particularly to phosphorescent pigment mixtures and techniques for dispersion of phosphorescent pigments.  
     BACKGROUND  
      Typically, phosphorescent pigments are either based on Zinc Sulphide or Stontium Aluminate chemistries. While these pigments have been used for a number of years and in a variety of applications, it has been difficult to incorporate these materials into fluid based materials, such as paints, inks, and the like. This is so, because conventional phosphorescent pigments have high densities and very specific processing parameters, which make it tough to integrate these conventional phosphorescent pigments into fluid-based materials.  
      That is, conventional phosphorescent pigments have high specific gravities and are often acquired in large particle sizes. These attributes make it difficult to properly and efficiently disperse conventional phosphorescent pigments into various materials and limit the applications of conventional phosphorescent pigments.  
      Still, phosphorescent paints have been attempted but with limited success. These paints are not capable of adequately absorbing ultraviolet (UV) light and maintaining an acceptable level of luminescence or intensity. To remedy this a variety of workaround techniques have been attempted, such as requiring a base white paint to be coated or primed onto a substrate before the phosphorescent paint is applied in an effort to provide better UV absorption and longer luminescence for the applied phosphorescent paint.  
      Moreover, because of the high specific gravity and ionic attraction of phosphorescent particles most phosphorescent paints are difficult to effectively apply to a substrate because the phosphorescent particles accumulate on the brush, roller, and/or applicator mechanism used to apply the paint. The result is a diluted having less than desired phosphorescent pigment that is distributed on the substrate.  
      Therefore, improved phosphorescent pigments and improved dispersion techniques for phosphorescent pigments are needed.  
     SUMMARY  
      In various embodiments, a phosphorescent dispersion mixture is provided. The phosphorescent dispersion mixture includes a doped aluminum silicate phosphorescent pigment material, a dispersant material, a resin material, and a liquid carrier material. In an embodiment, the liquid carrier material is further mixed with paint, ink, or plastic. The phosphorescent pigment material is included in the mixture at reduced particle sizes of 5 microns or less in diameter. In some embodiments, the diameter sizes of the phosphorescent pigment material are approximately 1 micron or less. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a diagram of a phosphorescent dispersion mixture, according to an example embodiment.  
       FIG. 2  is a diagram or a method for dispersing a phosphorescent mixture in a liquid solution of a product, according to an example embodiment.  
       FIG. 3  is a diagram of a phosphorescent dispersion system, according to an example embodiment. 
    
    
     DETAILED DESCRIPTION  
       FIG. 1  is a diagram of a phosphorescent dispersion mixture  100 , according to an example embodiment. The phosphorescent dispersion mixture  100  includes an aluminum silicate phosphorescent dispersion material  101 , a dispersant material  102 , a resin material  103 , and a liquid carrier material  104 .  
      Aluminum silicate (Al 2 SiO 4 )  101  is doped and includes phosphorescent characteristics and is referred to herein as “doped aluminum silicate phosphorescent pigment material”  101 . The doped aluminum silicate phosphorescent pigment material  101 , when excited by Ultraviolet (UV) radiation, such as light, glows in the dark or emits light in the dark.  
      The doped aluminum silicate phosphorescent pigment material  101  is acquired in solid form as particles. The particles have diameter sizes of approximately 5 microns or less. In an embodiment, the particle diameter sizes are approximately 1 micron. At these small particle sizes, the particles will remain suspended and dispersed in the liquid carrier material  104  without a tendency to accumulate with one another. This provides a more uniform distribution of the particles within the mixture  100 .  
      In an embodiment, the doped aluminum silicate phosphorescent pigment material  101  is mechanically ground and classified into sizes of 5 microns or less using pulverizing techniques, grinders, screens, and/or filtering techniques to acquire the crushed particles at the desired small sizes.  
      The phosphorescent mixture  100  also includes a dispersant material  102 . The dispersants can be anionic, cationic, or amphoteric. The dispersant material  102  may also be ethoxylates, sulfonates, phosphates, and the like.  
      A resin material  103  is also included in the phosphorescent mixture  100 . The resin material  103  is a low molecular resin material  103  having a molecular weight or approximately 500 to 25,000 and having a great affinity for the doped aluminum silicate phosphorescent pigment material  101 .  
      The phosphorescent mixture  100  also includes a liquid carrier material  104 . The liquid carrier material  104  may include water, aliphatic and aromatic hydrocarbons or any other solvent-based liquid.  
      The materials  101 - 104  of the phosphorescent mixture  100  are combined to form slurry. Any mechanical mixing technique may be used to mix the materials  101 - 104  with one another. The resulting slurry is the phosphorescent mixture  100 .  
      In an embodiment, the phosphorescent mixture  100  may be formulated to be a universal dispersion, such that it can be incorporated and/or mixed with a multitude of other solvents or resin systems. Additionally, the phosphorescent mixture  100  can be manufactured for water-based formulas with various types of resins  103 , such as acrylics, urethanes, epoxies, and/or alkyds. This is beneficial because commercial paint which is largely oil-based is flammable and new emerging standards are requiring the paints to be non-flammable and water-based. The mixture presented herein stays suspended and mixed in water-based paints providing a novel benefit over what has been conventionally achieved with phosphorescent pigment-based paints in the past.  
      According to an embodiment, the doped aluminum silicate phosphorescent pigment material  101  is produced by Visionglow LLC, of Australia. It is however to be understood that any doped aluminum silicate phosphorescent pigment material  101  may be used with the phosphorescent mixtures  100  presented herein and that the one produced by Visionglow is presented for purposes of illustrating an example doped aluminum silicate phosphorescent pigment material  101  having a favorable particle size of 5 microns or less and in some cases approximately 1 micron.  
      Each of the materials  101 - 104  maybe optionally concentrated within the resulting phosphorescent dispersion mixture  100  at desired ratios. For example and according to an embodiment, the doped aluminum silicate phosphorescent pigment material  101  may be concentrated within the mixture  100  at approximately a 40-70% ratio; the dispersant material  102  concentrated within the mixture  100  at approximately a 1-10% ratio; the resin material  103  concentrated within the mixture  100  at approximately a 1-40% ration; and the liquid carrier material concentrated within the mixture  100  at approximately a 1-50% ratio.  
      The novel phosphorescent mixture  100  may subsequently be combined with other products or solvents, such as paints, inks, and/or plastics. These products may then also be applied to other substrates, such as walls, etc. for purposes of exhibiting luminescent characteristics. Application of the products having the phosphorescent mixture  100  does not result in conventional problems because the aluminum silicate phosphorescent dispersion material  101  within the mixture  100  does not accumulate or attract in the manner that is exhibited by conventional formulations. The result is a doped aluminum silicate phosphorescent pigment material  101  that is more uniformly dispersed within the mixture  100  and thus the product to which it is subsequently mixed with. The phosphorescent characteristics and pigments are then more concentrated and affixed to the substrates on which they are applied in more evenly distributed manner. A more diffuse and even distribution of the phosphorescent material  101  on a substrate permits more UV radiation to be absorbed by the doped aluminum silicate phosphorescent pigment material  101 , which creates a better charge. Accordingly, the novel phosphorescent dispersion mixture  100  results in improved luminescence and improved application of solvents having the mixture  100  integrated therein.  
      In some formulations of the mixture  100 , a colorant may be added for purposes of producing a desired color, which is emitted by the mixture  100 . For example, the color red may be added to the mixture using red color phosphorescent pigment. Other colors may be configured or integrated into the mixture  100  as well, such as but not limited to, blue, purple, green, etc.  
       FIG. 2  is a diagram or a method  200  for dispersing phosphorescent mixtures in a liquid solution of a product, according to an example embodiment. The method  200  may be practiced in fabrication environments using equipment known to one of ordinary skill in the art in the pigment and phosphorescent arts. In an embodiment, the phosphorescent mixture is the mixture  100  described above with respect to the  FIG. 1 .  
      At  210 , particles of doped aluminum silicate phosphorescent pigment material are acquired in diameter sizes of approximately 5 microns or less. In an embodiment, at  211 , the diameter sizes are approximately 1 micron. In some cases, the doped aluminum silicate phosphorescent pigment material may be acquired in a mixture or slurry form, which has the particles of the desired sizes, such as the mixture  100  described in the  FIG. 1  above.  
      At  220 , the acquired particles of doped aluminum silicate phosphorescent pigment material are mixed in a liquid solution or form of a product. The doped aluminum silicate pigment material is mixed as a slurry and mixture, such as the mixture  100  described in  FIG. 1  above.  
      According to an embodiment, at  230 , the mixing with the liquid solution may occur with a product that is paint, ink, and/or plastic. That is the product may be in a liquid form in its native state, such as paint or ink. Alternatively, the product may be melted into a liquid form during its fabrication and subsequently acquire a different state, such as a plastic would acquire a native solid state after molded into its desired form.  
      In still another embodiment, at  240 , the resulting liquid version of the product having the dispersed particles of doped aluminum silicate phosphorescent pigment material may be further spayed onto another substrate, brushed onto the substrate, or rolled onto the substrate. In still other situations, at  240 , the substrate may be dipped into a bath of the liquid that has the particles of doped aluminum silicate phosphorescent pigment material. The substrate will exhibit enhanced luminescence capabilities that better absorb UV radiation and better emit light in darkness or low lit environments. These embodiments are useful when the product is in a native liquid form, such as paints or inks, and is applied to another substrate or product, such as paper, clothing, building materials, electronics, etc.  
      Example applications of the above presented technique for dispersing phosphorescent materials are numerous. For example, consider emergency exits associated with vehicles, aircraft, vessels, or buildings; these structures can have emergency exits and pathways to the emergency exits painted with a paint (liquid version of a product) that includes the particles of aluminum silicate phosphorescent material or the mixture  100  of  FIG. 1 . The result is an enhanced lighting environment in these structures when power is lost or darkness sets in; thereby providing improved safety for the occupants of these structures. Of course a variety of other applications are possible, such as coating roadways, integrating the particles of doped aluminum silicate phosphorescent pigment material into building materials, clothing materials, appliances, electronics, and the like. All such applications that include the particles of doped aluminum silicate phosphorescent pigment material are intended to fall within the scope of the embodiments presented herein.  
       FIG. 3  is a diagram of a phosphorescent dispersion system  300 , according to an example embodiment. The system  300  may be practiced by the method  200  of  FIG. 2  and may include the mixtures  100  of  FIG. 1 .  
      The phosphorescent dispersion system  300  includes a liquid solution associated with a product  301  and doped aluminum silicate phosphorescent pigment particles  302 . The liquid solution  301  and the doped aluminum silicate phosphorescent pigment particles  302  are mixed and integrated with one another to produce a phosphorescent dispersion-enhanced product  303 . The product  303  exhibits improved absorption of UV radiation or energy, includes doped phosphorescent pigment particles  302  more evenly dispersed throughout the product  303 , and exhibits enhanced luminescence by emitting more light in low lit environments or in darkness.  
      In an embodiment, the liquid version of the product  301  is a paint mixture, an ink mixture, or a plastic mixture. In some other embodiments, the liquid version of the product  301  may include rubbers, metals, or other materials that have been liquefied during a fabrication process. That is, the liquid version of the product  301  may be natively in a liquid state or may be made into a liquid state for purposes of fabrication.  
      According to an embodiment, the doped aluminum silicate phosphorescent pigment particles  302  are manufactured such that each particle has a diameter size of 5 microns or less. In one embodiment, the diameter size of the doped aluminum silicate phosphorescent pigment particles  302  is approximately 1 micron.  
      In some cases, other additives may be added to the doped aluminum silicate phosphorescent pigment particles  302 . That is, additives may provide better diffusion and integration of the doped aluminum silicate phosphorescent pigment particles  302  and/or may provide different characteristics to the resulting product to which it is applied. These additives may be directly integrated with the doped aluminum silicate phosphorescent pigment particles  302  to form mixtures or slurries, such as the mixture  100  of  FIG. 1 . Some example additives were discussed above with  FIG. 1  and can include, but are not limited to, resin materials having low molecular weights, colorants, aromatics, dispersant materials, and/or liquid carrier materials.  
      The above description is illustrative, and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of embodiments should therefore be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.  
      The Abstract is provided to comply with 37 C.F.R. §1.72(b) and will allow the reader to quickly ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.  
      In the foregoing description of the embodiments, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting that the claimed embodiments have more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus the following claims are hereby incorporated into the Description of the Embodiments, with each claim standing on its own as a separate exemplary embodiment.