ASI’s GSB-287® is an environmentally friendly cationic emulsion sealcoat that is specially formulated for use on commercial pavements. It encapsulates previously treated surfaces and restores, beautifies, and protects asphalt from the elements, while more than doubling service life.

GSB-287® works by filling voids and small cracks. It corrects surface raveling, levels minor depressions, and seals pavement surfaces from moisture.



gsb287-condition-graphAs it cures, GSB-287® dries to a rich black color, making your pavement look better than it did on the day it was installed. Because it is asphalt based, surfaces treated with GSB-287® don’t develop the hairline cracks common with non-asphalt surface treatments.

If applied while pavement is in good repair, GSB-287® can extend the life of asphalt for decades.


GSB-287® is specially formulated for use on asphalt that has been previously sealed. The Gilsonite-fortified treatment creates a tough, durable, long-lasting seal that can be used on any commercial bituminous pavement.

GSB-287® seals against UV rays, oxidization, temperature swings and precipitation. These environmental factors accelerate the raveling process on untreated pavement causing significant damage over time. GSB-287® is designed to be easily applied on top of other pavement treatments.


GSB - 287®

GSB-287 is a cationic asphalt emulsion seal coat uniquely formulated for use on commercial bituminous pavements. GSB-287 beautifies and protects asphalt pavements from the harmful effects of sunlight and oxidation, preventing moisture infiltration and protects the existing pavement and subgrade. GSB-287 may be applied over previous sealcoat treatments and cures to a flat black color in less than 4 hours.

GSB - 287VM®

GSB-287vm is a viscosity modified version of GSB-287 providing the same benefits and superior performance for asphalt pavements complete with friction enhancing properties. GSB-287vm is available to applicators and consumers. GSB-287vm is specifically formulated as a contractor friendly sealcoat that may be squeegeed, broomed, or spray applied with industry standard sealcoat equipment. Requires longer cure time than the GSB-287.
Consult with your ASI sales representative on dilution percentages and requirements.

GSB-287® Tech Sheet

GSB 287® Tech Sheet


GSB-287 / GSB-287vm Commercial Sealcoat

Technical Instructions & Specifications


Product Description:

GSB-287 and GSB-287VM (Viscosity Modified) are cationic asphalt emulsion based sealcoat products uniquely formulated for use on commercial and private bituminous pavements. GSB-287/GSB-287vm beautify and protect asphalt from the harmful effects of sunlight and oxidation. GSB-287/GSB-287vm prevent moisture infiltration therefore protecting the existing pavement and subgrade. GSB-287/GSB-287vm contain Gilsonite, a non-toxic, naturally occurring, 99.85% pure mineral asphalt ore known to enhance the performance of emulsions while promoting adhesion and durability. GSB-287/GSB-287vm are non-toxic, non-carcinogenic, containing no coal tar, and are non-flammable. These products comply with current VOC regulations nationwide making GSB-287 and GSB-287vm the environmentally friendly choice. GSB-287/GSB-287vm may be applied over previous sealcoat treatments. Applications generally dry in less than 4 hours and cure to a flat black color.

GSB-287vm is a viscosity modified version of GSB-287 providing the same benefits and superior performance for asphalt pavements complete with friction enhancing properties. GSB-287vm is available to applicators and consumers Ready-To-Use. This sealer goes from bucket, barrel, or application unit, straight to the pavement; no mixing is needed. GSB-287vm is specifically formulated as a contractor friendly sealcoat that may be squeegeed, broomed, or spray applied with industry standard sealcoat equipment.


Storage and Handling Instructions

GSB-287 may be stored and handled as any standard asphalt emulsion product. Heated, vertical storage tanks with mechanical agitators are recommended, with slow revolution agitation. GSB-287 may be supplied in a concentrate or RTU (ready to use - diluted) form. GSB-287 should only be stored in Concentrate form at temperatures not exceeding 140° Fahrenheit. For long term storage, temperatures should not exceed 100°-120° Fahrenheit. GSB-287vm will be supplied in RTU (ready to use) form and may be stored at ambient temperature.

Materials may be damaged by freezing. No long term storage under 40° Fahrenheit.


Instructions for use


GSB-287vm may be applied as any standard asphalt seal coat material. No special training or equipment is required. GSB-287vm may be spray applied, squeegee or brush applied using hand tools. Standard squeegee seal coat application machines or spray application machines are recommended. The equipment will be in good working order and contain no contaminants in the tank or pumping systems.

Manufacturer recommends GSB-287 be spray applied.

Addition of sand:

When an anti-skid surface is desired, GSB-287 may be top coated with sand. A hard, highly fractured, 20-40 sand is recommended. Applicators with physical agitation equipment and diaphragms pumps may add sand to the product before application. Storing the product with sand added is not recommended. GSB-287vm is supplied with friction enhancing properties.

Dilution :

When GSB-278 is supplied in a concentrate form, water should be added prior to application. Recommended dilution rates are either; 1 part concentrate emulsion to 1 part water, or 2 parts concentrate emulsion to 1 part water. The choice of dilution rate should be job specific. Manufacturer recommends a 2 to 1 dilute.

Note 1: When diluting the GSB-287 concentrate, always add the water to the concentrate emulsion.

Note 2: GSB-287VM is supplied Ready to Use. Do Not Dilute.

Latex Addition:

If latex additives are used, manufacturer recommends additives not exceed 1% to diluted sealcoats.

Preparation of Pavement Surfaces:

Before applying GSB-287/GSB-287vm, repair and patch all major pavement defects. All cracks, other than hairline cracks, should be filled with suitable crackfiller. Scrape oil spots to remove excess oil and dirt. Sweep or blow the asphalt surface of all loose dust, dirt, leaves and debris.

Prime Coat:

Priming of the existing asphalt surface should not be needed in most cases, provided the cleaning has been done correctly. If the pavement to be treated is very oxidized and dry or if there is a high surface tension on the pavement surface, a light prime coat may be need for a successful treatment. Suggested Prime coats are as follows:

GSB-78 ...........................................05 to .10 gallons per square yard.
GSB-88 1:1 dilute ...........................05 to .10 gallons per square yard.
CSS-1h 1:1 dilute ...........................05 to .10 gallons per square yard.

Prime coats should be dry and cured before applying GSB-287 or GSB-287vm.

Application Precautions:

GSB-287/GSB-287vm should not be applied to wet or damp pavement surfaces. Do not apply during rainy or damp weather or when rain is anticipated within 24 hours of application. Pavement surface temperatures should be 70°F and rising with ambient temperatures of 60°F and above. For optimum curing, allow at least three hours of sunlight after application. Shaded areas may require longer curing times. Consult the Material Safety Data Sheet for fire and explosion data, health hazard data, first aid procedures, reactivity data, spill or leak procedures, waste disposal and use of personal protective equipment. Additional copies of the Material Safety Data Sheet can be obtained by calling ASI,  at 1-801-972-2757.

Rate of Application:

The rate of application of GSB-287/GSB-287vm may vary with the texture, porosity and age of the asphalt pavement to be sealed. The following application rates are general recommendations using a GSB-287, 2 to 1 dilute product or GSB-287VM:

Single coat application over smooth pavement in generally good condition:
0.10 to 0.15 gallons per square yard

Double coat applications over rough or distressed pavement:

First Coat 0.2 gals/sq.yd.
Second Coat 0.15 gals/sq.yd.

(For superior performance the Manufacturer recommends 2 coats of GSB-287 or GSB-287vm).

Cure Time:

Cure time for GSB-287/GSB-287vm may be influenced by temperature and relative humidity. Under normal conditions, cure time is 4 hours at 70°. Sheltered or shady areas may also require longer cure times. With two coat applications, allow the first coat to dry before applying the second coat.

Clean Up:

GSB-287/GSB-287vm that has not dried may be removed by rinsing tools, equipment, and skin with water. Manufacturer recommends cleaning tools, equipment, curbs, etc. with environmentally safe, water based cleaners.

Striping and Pavement Markings:

Contact the paint manufacturer for recommendations.

Availability and Cost:

For further information on availability and cost of GSB¬-287 or GSB-287 contact Asphalt Systems, Inc., P.O. Box 25511, Salt Lake City, UT 84125-0511, call at 1-801-972-2757 .


Under normal wear and tear, proper application of GSB-Sealcoats should not require resealing for 3 to 5 years. High traffic areas will need to be sealed more often than low traffic areas. Reapplication of GSB-287/GSB-287vm should be at the recommended rates. Regular preventive maintenance can extend the life of asphalt pavement.

Warranty and Disclaimer:

Asphalt Systems, Inc. warrants GSB-287/ GSB-287 VM with respect to the quality stated herein. However, since the use of the product is beyond our control, our liability for damages shall in no case exceed the purchase price from Asphalt Systems, Inc., for the quantity of material consumed.

All products shipped shall meet or exceed the applicable specifications. Asphalt Systems, Inc., shall not be responsible for material after it has been stored in customer's tanks or for contamination from unclean trucks and shipping containers. Asphalt Systems, Inc., will assume no responsibility or liability for improper applications, skid resistance changes, thickening in storage, or any other conditions beyond our control.

This section sets forth the exclusive remedy for claims based on defects in or nonconformity of the product whether the claim is in contract, warranty, tort (including negligence) or otherwise. THE FOREGOING WARRANTIES ARE IN LIEU OF ALL OTHER WARRANTIES, WHETHER ORAL, WRITTEN, EXPRESS, IMPLIED OR STATUTORY, NO IMPLIED OR STATUTORY WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE SHALL APPLY.

ASI shall not be liable for any special consequential, incidental, indirect or auxiliary damages, including, without limitation, loss of profits or revenues, loss of use of products or any associated equipment, cost of capital, cost of substitute goods, facilities, services, downtime costs or claims of the purchasers customers for such damage. ASI's sole liability, and any liability of ASl suppliers, arising from the manufacture, sale, resale, use or application of the product shall not exceed the purchase price from ASI for the quantity of the product consumed.

ASI Flyer-GSB287