Resin chemistry · SPR 201
Orthophthalic Polyester Resins
The general-purpose unsaturated polyester family. Orthophthalic grades are built on phthalic anhydride and cover everyday FRP lay-up, casting, sheet production, moulding compounds, fire-retardant laminates and gelcoats.
Grades in this family
General and special-purpose grades
- SPR 201 GPCGP Clear ResinGeneral-purpose clear laminating resin for hand lay-up and spray-up. Also sold as Unsaturated Polyester Resin.Also sold as: Unsaturated Polyester Resin
- SPR 201 QMGP Quartz ResinListed in the catalogue as Quartz Marble Resin: engineered quartz, cast stone and cultured marble.
- SPR 201 BGRButton Grade ResinHigh-gloss casting resin for cast polyester buttons.
- SPR 201 CCPolyester Clear Casting ResinClear polyester casting grade for statues, idols and decorative articles. Not the epoxy Clear Casting Resin.
- SPR 201 CTGOrthophthalic Cooling Tower Grade ResinThixotropic grade for sag-resistant lay-up on vertical and large surfaces.
Roof-light and sheet grades
- SPR 201 SGYSheet Grade Yellow ResinPre-pigmented yellow resin for FRP sheet and panel work.
- SPR 201 RLRoof Light ResinWater-white resin for translucent roof-light and skylight sheets.
- SPR 201 RL (UV)UV-Stabilized Roof Light ResinUV-stabilized clear grade for roof-light sheets exposed to sunlight.
SMC and DMC grades
- SPR 201 SMC · SPR 201 DMCDMC/SMC ResinOrthophthalic resin for sheet and dough moulding compounds.
Fire-retardant grades
- SPR 201 FRFire Retardant ResinHalogenated fire-retardant laminating resin.
- SPR 201 FR (HF)Halogen-Free Fire-Retardant ResinHalogen-free fire-retardant laminating resin.
Gelcoat grades
- SPR 201 GCGP Gelcoat ResinWhite high-gloss surface gelcoat for general mould work.
- SPR 201 FR-GCOrthophthalic Fire-Retardant Gelcoat ResinFire-retardant surface gelcoat for rail and automotive parts.
Other orthophthalic grades in our range
Our product data states that these grades are orthophthalic, but they have no code in the 2026 catalogue system.
- GP White ResinWhite-pigmented grade on the shared GP base specification.
- GP Yellow ResinOrthophthalic general-purpose laminating grade.
- UV Stabilized Sheet Grade Yellow ResinPre-pigmented, UV-stabilized yellow sheet grade. A different product from the clear UV-Stabilized Roof Light Resin.
Selection guidance
- General hand lay-up and spray-up: start from SPR 201 GPC GP Clear Resin. The CC and CTG grades share its typical specification but serve casting and sag-resistant lay-up.
- Clear and decorative casting: SPR 201 CC for statues, idols and decorative articles; button work uses SPR 201 BGR.
- Roof-light and sheet production: SGY for general sheet, RL for roof-light sheet, RL (UV) where the sheet is exposed to sunlight.
- Fire-retardant laminates: SPR 201 FR is halogenated; FR (HF) is halogen-free. Confirm the requirement your project states.
- Surfaces: SPR 201 GC for general mould work; FR-GC to pair with a fire-retardant laminate.
This guidance identifies a starting grade only. Confirm the final choice against your own process and a trial.
Related application guides
Guides on the processes and applications this family serves.
Tell us which grade you need.
Describe the process, the finished part and its service conditions. Supply, pricing and packaging in Nepal are confirmed on enquiry.