Clear, general-purpose orthophthalic polyester resin.
- Viscosity
- 350–450 cPs
- Gel Time
- < 8 minutes
Resin chemistry · SPR 201 series
Orthophthalic Polyester Resins — SPR 201
Orthophthalic polyester is the general-purpose unsaturated polyester resin of the FRP industry: an unsaturated polyester built on phthalic anhydride (the ortho isomer) and dissolved in styrene, cured at room temperature with an MEKP initiator and a cobalt accelerator. It is the economical route for tanks, sheets, panels, doors, castings and moulded parts that do not face aggressive chemical or hot-water service. Samrat Poly Resins manufactures the SPR 201 orthophthalic series at Doraha, Punjab.
In the SPR 201 grades the catalogue lists, every grade is supplied non-accelerated: the initiator and accelerator are added separately during use at the reference dosages shown on each product page.
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Grades
Grades
SPR 201 · 5 grades
General and special-purpose grades
Orthophthalic polyester resin for engineered stone and quartz casting.
- Viscosity
- 400–800 cPs
- Gel Time
- 7–10 minutes
High-clarity resin for buttons and small mouldings.
- Viscosity
- 1,100 cPs
- Gel Time
- 9.5 Minutes
Clear orthophthalic polyester casting grade for statues, idols, decorative articles and furniture top coats.
- Viscosity
- 350–450 cPs
- Gel Time
- Under 8 minutes
Price on RequestTDS
Thixotropic orthophthalic grade for sag-resistant lay-up on vertical and large surfaces.
- Viscosity
- 350–450 cPs
- Gel Time
- Under 8 minutes
Price on RequestTDS
SPR 201 · 3 grades
Roof-light and sheet grades
Pre-pigmented yellow resin for consistent FRP sheet manufacturing.
- Viscosity
- 280 cPs
- Gel Time
- 6.5 Minutes
Water-white polyester resin for published roof-light and skylight sheet applications.
- Viscosity
- 280 cPs
- Gel Time
- 6.5 Minutes
UV-stabilized clear orthophthalic resin for roof-light sheets exposed to sunlight.
- Viscosity
- 200–400 cPs
- Gel Time
- 6.5–10 minutes
Price on RequestTDS
SPR 201 · 1 grade
SMC and DMC grades
The catalogue lists SPR 201 SMC and SPR 201 DMC as two entries with the same typical specification; both are supplied under the one DMC/SMC Resin product page.
Orthophthalic resin for dough and sheet moulding compounds.
- Viscosity
- 600 cPs (at 25°C)
SPR 201 · 2 grades
Fire-retardant grades
Halogenated FR polyester resin for industrial FRP requirements.
- Viscosity
- 400 cPs
- Gel Time
- 5.5 Minutes
Halogen-free orthophthalic fire-retardant resin for FRP laminates specifying halogen-free fire retardancy.
- Viscosity
- 1,500–3,500 cPs at 25 °C
- Gel Time
- 15–30 minutes at 25 °C
Price on RequestTDS
SPR 201 · 2 grades
Gelcoat grades
White, high-gloss polyester gelcoat for FRP mould surfaces.
- Viscosity
- 11,000 cPs
- Gel Time
- 8.5 Minutes
Thixotropic fire-retardant gelcoat for the mould-face surface of fire-retardant FRP components.
- Viscosity
- 5,000–11,000 cPs at 25 °C
- Gel Time
- 9–16 minutes at 25 °C
Price on RequestTDS
SPR 201 · 5 grades
Other orthophthalic grades on this site
Published grades whose own data sheets identify orthophthalic chemistry; they are not part of the SPR 201 catalogue series.
GP Resins · Orthophthalic
Unsaturated Polyester Resin
The versatile, general-purpose workhorse resin for FRP.
- Viscosity
- 350–450 cPs
- Gel Time
- < 8 minutes
GP Resins · Orthophthalic
Lamination Resin (LR Resin)
Transparent orthophthalic polyester resin for door & FRP lamination.
- Viscosity
- 400 cPs
- Gel Time
- 5 Minutes
GP Resins · Orthophthalic
GP White Resin
General-purpose orthophthalic resin for FRP moulding, on GP Clear Resin's base specification.
- Viscosity
- 350–450 cPs
- Gel Time
- < 8 minutes
GP Resins · Orthophthalic
GP Yellow Resin
Transparent yellow, general-purpose orthophthalic laminating resin.
- Viscosity
- 450–600 cPs @ 25°C
- Gel Time
- 10–15 minutes
Sheet Grade Resins · Orthophthalic
UV Stabilized Sheet Grade Yellow Resin
Pre-pigmented yellow polyester resin with a UV-stabilised formulation, for outdoor FRP sheet and panel work.
- Viscosity
- 280 cPs at 25 °C
- Gel Time
- 6.5 minutes at 25 °C
Price on RequestTDS
Orthophthalic grades compared
Typical values from each grade's published data sheet, for shortlisting. They are not guaranteed properties of a finished part.
| Grade | Viscosity | Gel time | Data sheet |
|---|---|---|---|
| GP Clear ResinSPR 201 GPC | 350–450 cPs | < 8 minutes | TDS |
| GP Quartz ResinSPR 201 QM | 400–800 cPs | 7–10 minutes | TDS |
| Button Grade ResinSPR 201 BGR | 1,100 cPs | 9.5 Minutes | TDS |
| SPR 201 CC Clear Casting ResinSPR 201 CC | 350–450 cPs | Under 8 minutes | TDS |
| Orthophthalic Cooling Tower Grade ResinSPR 201 CTG | 350–450 cPs | Under 8 minutes | TDS |
| Sheet Grade Yellow ResinSPR 201 SGY | 280 cPs | 6.5 Minutes | TDS |
| Roof Light Sheet Grade ResinSPR 201 RL | 280 cPs | 6.5 Minutes | TDS |
| UV-Stabilized Roof Light ResinSPR 201 RL (UV) | 200–400 cPs | 6.5–10 minutes | TDS |
| DMC/SMC ResinSPR 201 SMC · DMC | 600 cPs (at 25°C) | See data sheet | TDS |
| Fire Retardant ResinSPR 201 FR | 400 cPs | 5.5 Minutes | TDS |
| Halogen-Free Fire-Retardant ResinSPR 201 FR (HF) | 1,500–3,500 cPs at 25 °C | 15–30 minutes at 25 °C | TDS |
| GP Gelcoat ResinSPR 201 GC | 11,000 cPs | 8.5 Minutes | TDS |
| Orthophthalic Fire-Retardant Gelcoat ResinSPR 201 FR-GC | 5,000–11,000 cPs at 25 °C | 9–16 minutes at 25 °C | TDS |
| Unsaturated Polyester Resin | 350–450 cPs | < 8 minutes | TDS |
| Lamination Resin (LR Resin) | 400 cPs | 5 Minutes | TDS |
| GP White Resin | 350–450 cPs | < 8 minutes | TDS |
| GP Yellow Resin | 450–600 cPs @ 25°C | 10–15 minutes | TDS |
| UV Stabilized Sheet Grade Yellow Resin | 280 cPs at 25 °C | 6.5 minutes at 25 °C | TDS |
Choosing a grade
How to choose within orthophthalic polyester resins
Start from the process
Hand lay-up and spray-up start with SPR 201 GPC; clear decorative casting with SPR 201 CC; buttons with SPR 201 BGR; mineral-filled quartz and cultured-marble casting with SPR 201 QM.
Then the part
Sheet lines choose between SGY (coloured sheet), RL (roof-light) and RL (UV) (roof-light facing sunlight). Large vertical lay-up such as cooling towers uses the thixotropic SPR 201 CTG.
Then the requirement
A stated fire requirement moves to SPR 201 FR or the halogen-free FR (HF), with the FR-GC gelcoat on the surface. Hot water, chemical or sustained outdoor service is usually the point to move to the isophthalic SPR 301 family.
A family and a grade are a starting point. Suitability depends on the actual process, laminate, cure schedule and service environment, and the typical values on each product page are not guaranteed finished-component properties. Confirm the grade on a trial of the real part.
Guides
Read before you specify
What is GP Resin (GP Polyester Resin)?GP stands for General Purpose. A complete guide to GP polyester resin — what the name means, how it's made, its key properties, where it's used and how to select a grade.Types of Unsaturated Polyester Resin: A Grade-Selection GuideA product-role guide for buyers comparing standard UPR, GP, lamination, gelcoat, button, fire-retardant and vinyl ester options without treating them as interchangeable.ISO Polyester Resin vs GP Resin: When Is the Step Up Worth It?Isophthalic and orthophthalic resins look and handle almost identically in the workshop. Understand what actually changes in the backbone, where the difference shows up in service, and the cases where paying for isophthalic is simply wasted.How to Select Polyester Resin for FRP ManufacturingUnderstand the key factors when selecting polyester resin for different FRP manufacturing processes.Understanding Gel Time in Polyester ResinGel time is the working window between catalysing a polyester resin and it starting to set. What it means, what changes it, and what to check when it drifts.What Is DMC / SMC Resin? A Moulding-Compound Buyer GuideUnderstand Samrat Poly Resins' published orthophthalic UPR route for Dough Moulding Compound and Sheet Moulding Compound requirements, including what the current TDS does and does not establish.
Other resin chemistries
Browse by resin chemistry
SPR 301 · Isophthalic Polyester ResinsSPR 301 isophthalic (ISO) polyester resins made at Doraha, Punjab, for water, chemical and outdoor service: tank-lining, filament-winding, SMC/DMC, rock-bolt and gelcoat grades.SPR 401 · Terephthalic Polyester ResinsSPR 401 terephthalic polyester resins from Doraha, Punjab: SMC and DMC moulding-compound resins, a fire-retardant gelcoat and a heat-cured pultrusion grade.SPR 501 · Vinyl Ester ResinsVinyl ester resin family (SPR 501): when corrosion-resistant FRP linings and chemical-service structures call for vinyl ester instead of isophthalic polyester.FRP resin by jobStart from the part you make and find the matching grade and data sheet.Resin selectorAnswer a few questions about the process and part to shortlist grades.
Ordering orthophthalic resin: questions buyers ask
Choose the grade, send the quantity and delivery location, and we reply with a quotation. Call +91 74638 81652, message us on WhatsApp +91 74638 81005 or email info@samratpolyresins.in.
18 published grades: GP Clear Resin, GP Quartz Resin, Button Grade Resin, SPR 201 CC Clear Casting Resin, Orthophthalic Cooling Tower Grade Resin, Sheet Grade Yellow Resin, Roof Light Sheet Grade Resin, UV-Stabilized Roof Light Resin, DMC/SMC Resin, Fire Retardant Resin, Halogen-Free Fire-Retardant Resin, GP Gelcoat Resin, Orthophthalic Fire-Retardant Gelcoat Resin, Unsaturated Polyester Resin, Lamination Resin (LR Resin), GP White Resin, GP Yellow Resin and UV Stabilized Sheet Grade Yellow Resin. Each is manufactured at Doraha, Ludhiana, Punjab.
GP Clear Resin: 225 kg Drum; GP Quartz Resin: 225 kg Drum; Button Grade Resin: 225 kg Drum; Sheet Grade Yellow Resin: 225 kg Drum; Roof Light Sheet Grade Resin: 225 kg Drum; DMC/SMC Resin: 225 kg drum; Fire Retardant Resin: 35 kg / 225 kg; GP Gelcoat Resin: 50 kg / 225 kg; Unsaturated Polyester Resin: 225 kg Drum; Lamination Resin (LR Resin): 35 kg PET Packaging / 225 kg Drum; GP White Resin: 225 kg Drum; GP Yellow Resin: 225 kg Drum; UV Stabilized Sheet Grade Yellow Resin: 225 kg industrial drum. For SPR 201 CC Clear Casting Resin, Orthophthalic Cooling Tower Grade Resin, UV-Stabilized Roof Light Resin, Halogen-Free Fire-Retardant Resin and Orthophthalic Fire-Retardant Gelcoat Resin, packaging is confirmed with the quotation.
Prices are quoted on request, for your grade, monthly quantity and delivery location. Send those details on WhatsApp (+91 74638 81005), call +91 74638 81652 or email info@samratpolyresins.in. How ordering works.
Yes. GP Clear Resin, GP Quartz Resin, Button Grade Resin, SPR 201 CC Clear Casting Resin, Orthophthalic Cooling Tower Grade Resin, Sheet Grade Yellow Resin, Roof Light Sheet Grade Resin, UV-Stabilized Roof Light Resin, DMC/SMC Resin, Fire Retardant Resin, Halogen-Free Fire-Retardant Resin, GP Gelcoat Resin, Orthophthalic Fire-Retardant Gelcoat Resin, Unsaturated Polyester Resin, Lamination Resin (LR Resin), GP White Resin, GP Yellow Resin and UV Stabilized Sheet Grade Yellow Resin each link a technical data sheet (PDF) with the published specification.
Yes. Supply covers Punjab, Haryana, Delhi, Uttar Pradesh, West Bengal, Bihar, Jharkhand, Odisha, Assam and Andhra Pradesh, with exports to Nepal, Bangladesh, Ethiopia, Cameroon and South Africa.
Traders and distributors can send a dealer enquiry with their firm, location and expected monthly volume on the dealer and distributor enquiries page.
Enquiry
Discuss a orthophthalic resin requirement
Tell us the process, the finished part, the service condition and the quantity, and the technical team can suggest a starting grade to trial. Samrat Poly Resins manufactures at Doraha, Punjab. Pricing is on request.