Yoneyama Kagaku Kogyo Kaisha, Ltd.

Zinc sulfate

Product Features

  • We have the largest market share for high purity Zinc sulfate in Japan.
  • We prepare various grades, including food grade.
  • Our Reagent Special Grade comes at a 99.5% min purity.
  • We have many customers outside of Japan.
Zinc sulfate



Fiber drum of 50 kgs. net
(2 bags of 25 kgs. net in a drum) 

Basic Information

Chemical formula
Specific gravity
1.957 (25/4 degree C.)
Melting point
100 degree C.
54 grams/100 ml at 20 degree C.
White crystal
Harmonized system (HS code)
Country of origin
UN number
3077 (class 9/packing group III)


Reagent 1st Grade

Water solubility Almost clear
pH (5% liquid) 4.4 - 6.0
Chloride (Cl) 0.005% max.
Nitrate (NO3) Pass test
Substances not precipitated by ammonium sulfide 0.5% max
Lead (Pb) 0.003% max
Iron (Fe) 0.004% max
Ammonium(NH4) 0.004% max
Purity 99.0% min

Food Grade

Identification test
Free acid
No red color appears
Lead (Pb)
2μg/g max.
Alkali metal
0.5% max.
Alkaline-Earth metal
0.5% max.
Arsenic (As)
3μg/g max.
98.0 - 102.0%

Reagent Special Grade

99.5% min
Water solubility
pH (5% liquid/25 degree C.)
4.4 - 6.0
Chloride (Cl)
5ppm max.
Nitrogen compounds (as N)
0.001% max.
Sodium (Na)
0.005% max
Copper (Cu)
0.001% max
Calcium (Ca)
0.001% max
Cadmium (Cd)
5ppm max
Lead (Pb)
0.001% max
Arsenic (As)
0.5ppm max
Manganese (Mn)
3ppm max.
Iron (Fe)
5ppm max

Main Applications

  • Reagent
  • Pharmaceutical additive
  • Cosmetic raw material
  • Agricultural raw material
  • Eye drop raw material
  • Zinc-enhancer for powdered milk


Who are your main customers?
We supply our products to companies who need high purity Zinc sulfate for use as a reagent, or in food additives or cosmetics.

Who manufactures Zinc sulfate?

Yoneyama Kagaku Kogyo Kaisha, Ltd.

Aerial Shoot


  • We have been producing high-performance chemicals using crystallization technology since 1918.
  • We have achieved stable quality because we control the manufacturing process by a quantitative method.
  • We produce phosphates, acetates, chlorides and sulfates which are conformable to the Japanese standards of quasi-drug ingredients typically used for cosmetics, shampoos, body soaps, and hair care products.


1918 Established in Osaka prefecture, Japan.
1962 Ashikaga Plant was created.
1966 Ashikaga Plant starts producing Ammonium acetate.
2001 Company acquires ISO 9001 certification (all business units).

Company Overview (as of March 31, 2020)

Company name Yoneyama Kagaku Kogyo Kaisha, Ltd.
Head office 5-2-18 Nishitenma, Kita-ku, Osaka, 530-0047, Japan
Date of establishment July 10, 1918
Capital JPY 24 million
Number of employees 90
Location Head office: Osaka
Branch offices: Tokyo, Nagoya
Plants: Osaka, Ashikaga
Technical department : Osaka
Affiliates: Suita (Osaka)


Plant location map

Osaka Plant

  • Phosphates
  • Sulfates

Ashikaga Plant

  • Acetates
  • Boric acid
  • Ammonium salts

Other Plants

  • p-Nitrobenzoic acid
  • Zinc sulfate
  • Potassium tetraborate

" End-User’s Laboratory "

Equipment for end-user’s pilot and small-scale production using our excellent crystallization technology


  • Production volume 100 - 1000 kgs.
  • We have facilities that can develop chemicals that meet the standards for reagent special grade, food additives, and capacitors.
  • Using the manufacturing data accumulated in the development process, you can move to mass production accurately and quickly.

Main Equipment

Device Name Capacity Quantity Material made of Comment
Feed tank 3,000 L 1 GL Room temperature to 120 degree C., full vacuum to atmospheric pressure
3,000 L 1 SUS Room temperature to 120 degree C., full vacuum to atmospheric pressure
Crystallization tank 3,000 L 1 SUS Room temperature to 120 degree C., full vacuum to atmospheric pressure
Filter 250mm x 5 1 SUS Cartridge type
80 L, 0.2 m2 1 SUS Nutsche type
Centrifuge 42 inches, 165 L 1 SUS Fully open, bottom ejection type
Conical dryer 300 L 1 SUS 40 to 120 degree C., full vacuum to atmospheric pressure
Loading chamber 18 m2 1 SUS Positive pressure control, HEPA filter
Kneader 50 L 1 SUS Room temperature to 120 degree C., full vacuum to atmospheric pressure

Case Study

1. Purification of water-soluble compounds

This labo's purification process removes impurities and provides them to users in pharmaceutical applications who require high purity products. "Purification of water-soluble compounds" is our specialty, and we often undertake requests for such purification in small lots (100 - 500 kgs.).

2. Purification and reduction of Fe of ammonium organic acid for plating

We have reduced impurities in ammonium organic acid, which is used as a complexing agent and buffer, by an impurity removal process + neutralization reaction + crystallization method. As a result, we are able to crystallize "high purity" and "low Fe value" crystals.