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Flame Retardants REACH

Tetrakis(hydroxymethyl)phosphonium sulfate

CAS Number
55566-30-8
EC Number
259-709-0
Chemical Formula
C4H12O4P.1/2O4S
Molecular Weight
406.28 g/mol
Industries:Water TreatmentPersonal Care & CosmeticsTextile, Leather & Paper

Description

Tetrakis(hydroxymethyl)phosphonium sulfate (CAS 55566-30-8 ), commonly known as THPS, is a water-soluble organophosphorus biocide and flame retardant used across industrial and specialty chemical markets. Supplied under trade names such as Retardol S and Pyroset TKO, it delivers broad-spectrum antimicrobial activity alongside durable flame retardancy in treated substrates for various sectors. In water treatment, THPS controls sulfate-reducing bacteria and biofilm formation in oilfield injection systems, cooling towers, and industrial process water systems to maintain operational efficiency. Textile and nonwoven manufacturers apply it as a durable flame retardant finish for cotton and cellulosic fabrics, where it bonds to fiber during curing to meet fire performance standards. In leather processing, it functions as a biocide during hide preservation and wet-end operations to prevent microbial degradation. This ensures the quality and longevity of the leather materials. Personal care and cosmetic formulators incorporate it at low concentrations as a preservative active against a broad range of bacteria and fungi, ensuring product safety and shelf stability. THPS is commercially available as an aqueous solution, typically at 75% active content. It is supplied in technical grade for industrial water treatment and textile applications. Select grades meet specifications for cosmetic preservation use. Packaging options generally include drums and intermediate bulk containers (IBCs) to suit varying procurement volumes and logistics. Contact us for supply of Tetrakis(hydroxymethyl)phosphonium sulfate Request Quote

Other Names (Synonyms)

Retardol S | Pyroset TKO | Octakis(hydroxymethyl)phosphonium sulfate | NCI-C55050 | Phosphonium, tetrakis(hydroxymethyl)-, sulfate (2:1) (salt) | Phosphonium, tetrakis(hydroxymethyl)-, sulfate (2:1) | THPS

Key Technical Features

  • High Purity Grade standard
  • Consistent Batch Quality
  • Full Regulatory & REACH Support
  • Global Logistics Network enabled

Physical Properties

Melting Point-35°C
Boiling Point111°C
Density1.41 g/cm³ @ Temp: 20 °C
Flash Point96 °C
ColorColorless to Almost colorless
Formliquid
Water Solubility>=10 g/100 mL at 18 ºC
Vapor Pressure0Pa at 20℃
Log P-9.8

Safety & Handling

Danger
GHS05· CorrosiveGHS06· ToxicGHS07· IrritantGHS08· Health HazardGHS09· Environment

Hazard Statements

H301Toxic if swallowed
H302Harmful if swallowed
H317May cause an allergic skin reaction
H318Causes serious eye damage
H330Fatal if inhaled
H331Toxic if inhaled
H360May damage fertility or the unborn child
H361Suspected of damaging fertility or the unborn child
H372Causes damage to organs through prolonged or repeated exposure
H373May causes damage to organs through prolonged or repeated exposure
H400Very toxic to aquatic life
H410Very toxic to aquatic life with long lasting effects
H411Toxic to aquatic life with long lasting effects

Precautionary Statements

P203Obtain, consult and follow expert instructions for use.
P260Do not breathe dust/fume/gas/mist/vapours/spray.
P261Avoid breathing dust/fume/gas/mist/vapours/spray.
P264Wash … thoroughly after handling.
P270Do not eat, drink or smoke when using this product.
P271Use only outdoors or in a well-ventilated area.
P272Contaminated work clothing should not be allowed out of the workplace.
P273Avoid release to the environment.
P280Wear protective gloves/protective clothing/eye protection/face protection.
P284In case of inadequate ventilation wear respiratory protection.
P316Get emergency medical help immediately.
P317Get emergency medical help.
P318IF exposed or concerned, get medical advice.
P319Get medical advice/attention if you feel unwell.
P320Specific treatment is urgent (see … on this label).
P321Specific treatment (see … on this label).
P330Rinse mouth.
P391Collect spillage.
P405Store locked up.
P501Dispose of contents/container in accordance with local regulations.
P265Wash … thoroughly after handling.
P316Get emergency medical help immediately.
P317Get emergency medical help.
P352IF ON SKIN: Wash with plenty of water.
P340IF INHALED: Remove person to fresh air and keep comfortable for breathing.
P317Get emergency medical help.
P364Take off contaminated clothing and wash it before reuse.
P233Store in a well-ventilated place. Keep container tightly closed.
P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.

Trade & Regulatory

HS Code29319019
UN Number2922
ADR Class8
Packing GroupIII
Storage Class6.1C - Combustible acute toxic Cat.3 toxic compounds or compounds which causing chronic effects
WGK (Germany)1