Detailed Product Description

Raw material  Yellow phosphorus    

Applications  Phosphoric acid is used in a variety of applications, including etching in the manufacturing of pure semiconductor chemicals and TFT-LCDs, metal surface treatment, phosphates, food additives and beverages, wastewater treatment, refractories, catalysts, and so on.

Introduction  YS fine Chemicals phosphoric acid is manufactured from elemental phosphorus by oxidation and hydration. It is less acidic than sulfuric or hydrochloric acid and more stable at high temperatures. YS fine Chemical uses a thermal process to produce several grades of phosphoric acid, including electronic, food and technical grade. Our production of phosphoric acid electronic  grade is ranked front in Guangxi China . (more)

Application

Wet chemical etching 

Wet chemical etching is used in the TFT-LCD manufacturing process.

There are two etching processes: a wet chemical etching process, in which acids and other chemical solutions are used; and a dry chemical etching process that uses gas plasma.

1) In wet etching, a chemical solution is used to etch a thin film. A mixture of phosphoric acid, hydrochloric acid, and nitric acid is used to perform the etching. This etching solution dissolves the portions of the thin film that are not covered by photoresist. The photoresist forms a protective layer atop the thin film on which patterns are to be formed. 

  2) In dry chemical etching, plasma is used to generate gas radicals, such as fluorine radicals, in order to etch the thin film. Plasma removes any portion of the thin film that is not covered by photoresist. TFT-LCDs are used for computer monitors, cellular phones, GPS devices, educational games, advertisements, televisions, etc.

  Metal surface treatment

Phosphoric acid, a good pickling agent, can be used to remove the oxide scale on sheet steel without damaging the steel. Coated with a thin film of iron phosphates.  

Phosphoric acid-nitric acid solutions are used to chemically polish aluminum prior to anodizing. The mixture selectively attacks protrusions on the metal surface, resulting in an overall level surface. Copper and brass can also be chemically polished using phosphoric acid. Aluminum, steel (including stainless steel), and other metals are electropolished using relatively high concentrations (50-80%) of phosphoric acid solutions that contain sulfuric and chromic acids as well as other additives.

Food-additives

In a diluted solution, phosphoric acid is non-toxic and has a pleasing, slightly sour taste similar to citric and acetic acids commonly found in food. For this reason, it is often used as a flavoring agent in cola beverages. Other applications include its use as a general protein acidulant, a buffering agent in jam and jelly preparation, a nutrient and buffer in the manufacture of antibiotics, a cleaner for dairy equipment and a purification reagent in sugar refining.

Phosphates  

In phosphate salts, any or each of the three acidic protons of phosphoric acid are replaced by cationic species. The phosphate salts of most elements are known and the number of distinct species is quite large when all minerals, salts, hydrates, and polymorphic varieties are considered. Commercial phosphates include alkali metal, alkaline earth, heavy metal, mixed metal, and ammonium salts of phosphoric acid. Sodium phosphates are the most important, followed by calcium, ammonium, and potassium salts.

Refractories

Phosphoric acid is used as a bonding agent in various refractory products, particularly alumina, but also magnesia, zirconia, and carbon refractories. Phosphate-bonded refractories typically show improved green strength, load-bearing properties, high temperature stability, and good resistance to abrasion.

Catalysts

Catalytic applications involving phosphoric acid make use of its acidic and dehydrating properties. Typically, catalytic uses for phosphoric acid include the production of gasoline and nylon.

Others

Other uses for phosphoric acid are numerous and the range of applications is quite wide, including wastewater treatment, wood and fabric flameproofing, boiler cleaning, opacity control in glass manufacturing, textile dyeing, rubber latex coagulation, lithographic engraving, and dental cements.

Phosphoric acid is a colorless, odorless liquid. It is a weaker acid than sulfuric acid, nitric acid

or hydrochloric acid, and is relatively non-volatile and stable at elevated temperatures.

Phosphoric acid is manufactured either by the thermal or wet process. Phosphoric acid by the

wet process has fluorine, organic compounds, and sulfate groups because the process cannot

completely remove impurities. On the contrary, the thermal process can produce high quality

products.