HORIBA LA-series particle size distribution analyzers has found uses in quality control, process material evaluation, and development in the following materials:

• Ceramics, metal and other inorganic powders
  
• Polymers and organic particles
  
• Ores and minerals
  
• Pigments and dyes
  
• Food and pharmaceutical products
  
• Process effluents
  

Physical properties of ceramic and metallic alloys are dependent on the size of feed materials. For instance, the crystalline structure of intermetallic compounds is affected by the particle size of the feedstock. Different grades of industrial diamond are used for different abrasive or polishing purposes. The grades are decided by the particle size distribution of the diamonds.

The particle size for catalyst is very important in controlling the rate of a reaction. Too small a size can mean rapid oxidation of the metal catalysts, which renders them useless in process catalysis.

Optical and magnetic storage devices require strict control of their material particle size. The sensitivity and resolution of photographic images are dependent on the size of the film emulsion materials. Similarly, the toner used for laser printing requires control of the particle size to ensure quality printing. The magnetic particle size distribution of computer diskette and hard disk drive is important to ensure accurate information storage.

Reaction and dissolution rates in solutions are controlled by particle size. This is especially true in the production of polymers and the final plastic products. Natural rubber can have different particle size distribution based on the rubber species (Gutta Percha A or B). The handling of organic materials such as starch, flour, and sugar in air can be hazardous below a certain particle size because they can be easily oxidized or burnt in air.

Energy production using cyclone burners with coal feedstock requires that the coal particles to be in the range of 5 mm to 10 mm for the best combustion efficiency. Fly ash from power plants is harmful to human health and the environment. Particle size distribution analysis is required to ensure the ash emitted is below the regulated size.

The particle size distribution of clay minerals is important in the production of pottery products.

Appearance and texture, as well as the tone of color of a material are affected by the particle size of the powder used in its preparation. This can be illustrated by cosmetics. The reflection and absorption of light is strongly affected by the particle size distribution of the coloring material. The texture of cosmetics is also controlled by the size of the powder used.

The taste, as well as the texture, of many food products is affected by the size of the particles, which make up that food. For example, the texture and mouth feel of chocolate products are different and this can be directly attributed to differences in the cocoa and sugar powder sizes used in the production process. Other examples are in the manufacture of tomato ketchup, coffee and milk powders, and flour.

The size of drug particles is important because of its effect on the appearance, texture, or taste of the drug, as well as the rate of absorption by the human body. For example, insulin zinc suspension (crystalline) B.P., which contains particles between 10 mm to 40 mm has a longer duration of action than insulin zinc suspension (amorphous) B.P., where the particles are less than 2 mm. Eye ointments must be free from large particles that will cause irritation to the eyes. The timing of the release of drugs is also controlled by the particle size distribution. Antiworm drugs must be effective in the gut and so the drug particles must be small enough to be dissolve in the gut but large enough so as not to dissolve before the gut is reached.

The solid particle size distribution in process fluids is important in the manufacture of the final products. For example, the polishing slurry used in the semiconductor industry has to conform to certain particle size distribution so that the wafers will not be scratched during the polishing process. In addition, different grades of finishing will require polishing slurries with different particle size distributions.

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