Product Features & Benefits:

These resins are tailor make to meet the diverse needs of GRP/FRP industry and meeting the requirements of customers interest of improved efficiency and superior performance of finished product.

GELCOAT is a thixotropic, quick-curing superior phthalic anhydride and propylene glycol based unsaturated polyester resin for general coating thixotropic applications. It is neither waxed nor pre-accelerated and suitable for both hand lay-up application and gun spray application. However, gun spray- up application is preferable because it can apply the resin evenly and spreading a thin coat without any pinholes.

Gelcoat resin coated surface is glossy after cured. It has good mechanical properties and water resistance and is resistance to mild chemicals and ultra-violet light, thus enhancing the durability of glassfibre reinforced plastics (GRP) products. Besides, the time between gelation and cure is short for espol™ 20.00 gelcoat resin and therefore productivity can be increased.

As a gelcoating agent, gelcoat resin can be applied, using general purpose resin as back up material, to a variety of GRP products. To improve the quality of a GRP product, general purpose laminating resin is recommended as back up material of RTM grade for RTM processing.
gelcoat resin mixed with colorants can be used as translucent coating material.

Physical Data In Liquid State At 250c# [confirm To Is 6746-1994 And Bs 3532 - 1990]

Properties Units Values Test Method
Appearance - Pale Yellow (TM-01)
Specific Gravity - 1.08 ± 0.02 (TM-11)

  • Ford Cup 4 @ 300C
  • Brookfield RVT model #
mPa s(cps)
60 ± 10
200 ± 50
Volatile Content % 34 ± 36 (TM-08)
Thixotropic index(TI) Ratio 3 - 3.5 (TM-05)
Acid Value mg-KOH/gm 25 ± 3 (TM-06)
Gel time @ 300C Minutes
15 - 25*
10 - 15ω

Peak Exotherm Temp. 0C 135 - 145 (TM-07)
  • * Using Accelerator, Co (2%) 1 ml, Catalyst, MEKP1.5ml, the gel time, cure time and Peak Exotherm measured.
  • * Summer ω Winter [TM - Test Method as per ISO-9001-2000-DOC-REV-03]

Properties of cast Resin Laminate:

Properties Units Values Test Standards
a) Barcol Hardness BHU 35 ASTM D - 2583
b) Heat Distortion Temp. 0C min 65 ISO - R75
c) Specific Gravity - 1.22 ± 0.02 ISO - R1183
d) Volume Shrinkage on cure % 7 ISO - 3521
e) Tensile Strength N/ 60 ± 10 ISO - R 527
f) Tensile Modulus N/ 3200 ± 100 ISO - R 527
g) Elongation at break % 2.5 - 3.5 ISO - R 527
h) Flexural Strength N/ 90 ± 10 ISO - 178
i) Flexural Modulus N/ 3500 ± 100 ISO - 178
  • * When post cured after maturation.


The general purpose Roof Light Polyester resin performs best if the laminate is completely post cured. The quantity of catalyst and accelerator can be adjusted to get a shorter or longer gel time.

Post Curing:

It is recommended to mature the products for 24 hours and post curing should be done for minimum of five hours at 800C, or 2-3 weeks at room temperature. This is essential for getting the optimum properties.

Storage / Handling:

The polyester resin remains stable for 3 months at 300C in the dark and 4 months at 250C. The resin stability deteriorates markedly at elevated temperature, especially when exposed to direct sunlight has a flash point of 340C and is classified as flammable. "NO SMOKING " rules should be strictly followed. In case of spillage, use sand or earth to absorb and shovel off for disposal as per local regulations, In case of fire, use dry chemical foam, Carbon dioxide or water spray to extinguish the flame.


The Polyester resin is packed in HDPE carboys ( 30, 35, 40 & 45 kgs ) and epoxy coated steel drums HDPE barrels
(220 kgs) of standard size net weight. Special packing size offered for projects on returnable containers. Technical services are also provided to comply standards.

Health & Safety:

Never add metal salts (Accelerator) or Pre Acceleratorated resin to Peroxides when adding peroxides to a resin solution, mix thoroughly the resulting product Do not add organic peroxides to a hot diluents or process. Prevent contamination of Acclerator, promo0ter from materials like ( Iron Copper, Cobalt ) salts, storing acids and sanding dusts. Suggested containers are glass, polypropylene, Teflon, Poly-ethylene or stainless steel to prevent contamination of material during its handling.