FILCO® 350 is an unsaturated polyester resin in a non-ionic water emulsion, serving as a film former in sizings for glass fibers. The appearance is a milky liquid, and characteristics of the resulting film include being clear, non-tacky, and compatible with unsaturated polyesters. It also exhibits rapid solubility in styrene.

Functions: Film Former

Chemical Family: Polyesters, Unsaturated Polyester (UPE)

Compatible Polymers & Resins: Epoxies (EP), Unsaturated Polyester (UPE)

Processing Methods: Spray Lay-up

Technical Data Sheet

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Identification & Functionality

Composite Materials Functions

Features & Benefits

Product Characteristics
  • Clear, not tacky.
  • Compatible with unsaturated polyesters.
  • Very quickly soluble in styrene.

Applications & Uses

Compatible Polymers & Resins
Compatible Reinforcements
Composites Processing Methods

FILCO® 350 film-formers for Spray-up Roving ester and Roving for Mat polyester and epoxy dispersions

  • Hard filmquickly soluble in styrene
  • High compatibility with all types of unsaturated polyester matrices


Physical Form
Milky liquid
Typical Properties
ValueUnitsTest Method / Conditions
Solid Content45.0%-
Glass Transition Temperature (Tg)63°F-
Physico-Chemical Properties
ValueUnitsTest Method / Conditions
Solid Content44 - 46%MA145LFE
Viscosity (at 25°C, #2, 20rpm)max. 1000mPa.sMA143LFE
pH2 - 4-MA148LFE
Average Particle Size600 - 1000nmMA147LFE
Particle Size Distribution
ValueUnitsTest Method / Conditions
Average Particle Size800nm-

Packaging & Availability

Regional Availability
  • Canada
  • Mexico
  • USA

Storage & Handling

Shelf Life
9 months
Storage and Shelf Life Conditions
  • FILCO 350 should be stored in closed containers away from direct sun rays, at temperature between +5 and +30°C.
  • In these conditions maximum suggested storage time is 9 months from production, in the original package. After that date product must be rechecked.