The development of "SeLatex," a deproteinized natural rubber, makes gloves comfortable for people with sensitive skin.

"SeLatex" is a new type of natural rubber, in which a unique method has been used to analyze and extract the proteins, thought to be one of the causes of rough skin. Our products using the material meet a variety of new needs, including that of anti-allergen rubber.

New Rubber research Consortium has been researching in the purified natural rubber latex and solid natural rubber ,and developed deproteinized natural rubber latex. It means highly-purified latex made by decomposition of proteins with enzyme(protease) and surfactant, then clearing away the decomposed through dilution and centrifugation processes. These treatments give it exellent features such as low allegenicity,softness,etc,which features usual or other low protein natural rubber latices are never able to demonstrate. We, SUMITOMO manufacture and sell this latex called SeLatex as a trade name. Its structure and manufacturing process are illustrated as follows.

Features & Application

Features of SeLatex

Property Feature
(compared to NRL)
Ground for the Feature Application
Latex protein allergy Low allergenicity Proteins in NRL are decomposed and clearedaway. Allergenicity of SeLatex is 1/200 - 1/900 Glove,Cathetel, Other medical Use Mattress,Pillow,Condom
Rubber smell,Storage No smell of rottenness Good storage SeLatex has less protein than NRL has, protein which forms smell when becoming rotten All NRL products
Resilience Modulus Strength -Good -Low -about 10% down Fatty acid salts are supposed to be taken away which may facilitate crystalization of rubber under stretched High resilience,Low modulus. Improve softness of products. Glove,Cathetel,Rubber thread(for socks or diaper)
Modification Good reactivity Proteins on the surface of rubber particle are eliminated. Modifying agent can then directly attack rubber particle. MMA-graft, Depolymerized latex, Epoxy-modified latex
Electrical resistance Water absorption -High -Low Less hydrophilic non-rubber Component Electrical glove
Vulcanization a little lower Less vulcanization activator like amines in the latex Recovered by increasing curing agents  


SeLatex is most suitable for a medical use such as medical gloves,cathetels, sticking plasters,etc for its low allergenicity,which also makes SeLatex applicable for mattresses and condoms. SeLatex is good for rubber thread, household or working gloves because of its improved softness and high resilience. Moreover, it is easily modified and therefore finds its application in adhesives.The products made of SeLatex are given not only low allergenicity but also many other excellent features.

Examples for application

  • Rubber Glove (Surgical, Dental, Examination, Household, Working)
  • Cathetel, Medical Tubing
  • Latex Foam Rubber (Mattress, Pillow, Sponge Puff etc)
  • Adhesive (Sticking plaster, Medical Tape, Electrical Insulation Tape etc)
  • Latex Thread
  • Condom Rubber Balloon

Latex-Protein Allergens

We measure the Latex-Protein Allergen (Antigen) about SeLatex ,NR latex and their products. These measurements are done by BGFA of Ruhr University, Germany and the Guthrie Research Institute, USA with our request. They are the basical data for the estimation (judgement) of Latex-Protein Allergy.It is shown that SeLatex have little latex-protein allergens or antigens. These facts prove that the process applied for SeLatex is very superior in clearing away the protein allergens.

SAMPLE Latex-Protein Allergen
(RAST-inhibition in CAP system)
Antigenic Protein
by Guthrie Research
(LEAP assay)
SELATEX 3821 4.34 µg/ml latex < 0.1 µg/ml
SELATEX 6111 2.75 µg/ml latex < 0.1 µg/ml
SELATEX 1101 0.77 µg/ml latex < 0.1 µg/ml
SELATEX 5101 - < 0.1 µg/ml
HA-NR Latex 724 µg/ml latex 1766 µg/ml
Surgical Glove(SeLatex) None Detectable < 0.2 µg/g
Dental Glove(SeLatex) - < 0.2 µg/g
Dental Glove(HA-NRL) - 181.4 µg/g

Types of SeLatex

We can manufacture and sell various SeLatex by means of different raw NR latex and different process condition. At present SeLatex3821 is produced as a general- purpose grade in Thailand. Special grade also can be made on orders. The price of SeLatex is influenced by several conditions such as a price change of raw latex, the purity (type) and a purchase quantity. (*1)

Type Raw Latex Purification Process Nitrogen content(*2)
SELATEX 3821 Field latex Single Centrifugation <= 0.15
SELATEX 6111 Field latex Double Centrifugation <= 0.035
SELATEX 1101 NR latex Single Centrifugation <= 0.05
SELATEX 5101 NR latex Double Centrifugation <= 0.03

(*1)Please let us know your commercial conditions at the following mail-address, and you will get the actual price quotation of SeLatex
(*2) Measured with Kjeldahl method Unit: wt% on Solid Content

The other representative properties of SELATEX3821 are as follows.
TSC(DRC):60.0-62.0% ,Viscosity:50-100cps , MST:>=400sec.
Total Alkalinity(as NH3):0.3-0.5% ,Coagulum Content: <=0.01%