FILCO® 366 is a highly unsaturated polyester resin meticulously dispersed within a non-ionic water dispersion, dedicated to serving as a film former in glass fiber sizings. Its appearance is that of a milky liquid. Key product characteristics encompass its high unsaturation, integration of a non-ionic emulsifier within the polymer, stability against hydrolysis and sedimentation, a narrow particle size distribution, and high mechanical shear stability, even in diluted emulsions.

Functions: Film Former

Chemical Family: Polyesters, Unsaturated Polyester (UPE)

Technical Data Sheet

Ask P.A.T. Products Questions

Leo Coyle avatarErik Espling avatarLogan York avatar

Enhanced TDS

Identification & Functionality

Composite Materials Functions

Features & Benefits

  • Highly unsaturated
  • Non-ionic emulsifier built in the polymer
  • Hydrolysis and sedimentation stability from pH 1 to 6 = min. 48 hours
  • Narrow particle size distribution
  • High mechanical shear stability of diluted emulsion
Characteristics of Film
  • Clear
  • Not tacky
  • Fully crosslinked
  • Low solubility in styrene

Applications & Uses

Compatible Reinforcements
Processing Information

FILCO® 366 is suggested as film former for glass fiber sizes for:

  • SMC roving
  • BMC roving
Application Characteristics
  • slow solubility in styrene
  • superior surface appearance of the composite


Physical Form
Milky liquid
Typical Properties
ValueUnitsTest Method / Conditions
Solid Content44%MA145LFE
pH1 - 4-MA148LFE
Viscosity100 - 5000mPa.sMA143LFE
Particle Size Distribution
ValueUnitsTest Method / Conditions
Average Particle Size400nmMA147LFE

Packaging & Availability

Regional Availability
  • Canada
  • Mexico
  • USA

Storage & Handling

Shelf Life
6 months
Storage and Shelf Life Conditions

FILCO® 366 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 6 months from production, in the original package. After that date product must be rechecked. Prevent from freezing.