InstaGel Spray 40 is a unique two component, flexible, 100% solids polyurethane elastomeric compound. InstaGel Spray 40, when fully cured, provides for a tough, flexible stand-alone mold that does not requirement containment boxes. InstaGel Spray 40 is applied using a simple, inexpensive hand held Hopper gun, replacing the need for expensive high pressure application equipment. InstaGel Spray 40 is recommended for architectural, fine art or natural texture reproduction.

Application and Mix Ratio

Liquids should be maintained at 72˚F for best results. Warmer temperatures will decrease working life, cooler temperatures will increase application time.

Mold surface preparation:
All surfaces should be dry and free of visible dirt and debris.

Clay Surfaces: Non-drying oil based clay masters should be coated with a liberal application of urethane mold release (available from Industrial Polymers) and allow to dry for 15 to 20 minutes before applying InstaGel Spray 40.

Wood Surfaces: Wood possess a special problem due to surface porosity and moisture content. Sealing surfaces with several coats of shellac or wax will prevent any unwanted adhesion. After sealing, apply a liberal coat of Urethane mold release agent to sealed surfaces and allow to dry 45 minutes to 1 hour before applying InstaGel Spray 40.

Concrete or Stone Surfaces: Surfaces should be clean and dry. Seal surfaces with petroleum jelly or wax. If the Stone surface is smooth enough, a liberal coat of Urethane mold release alone will be sufficient for release. Allow the Urethane mold release to completely dry (1 hour) before applying InstaGel Spray 40.

Metal: Surfaces should be clean and dry. A liberal coat of Urethane mold release on smooth molding surfaces and/or with wax on rough surfaces will easily release.

Choose a work area that is free from visible moisture and capable of maintaining a temperature range of 70˚F to 90˚F. Gloves, eye protection and respirators must be worn during spray application (see Industrial Polymers Safety Data Sheet for more details).

All surfaces should be clean, free of dirt and visible moisture before and during application. After temperature stabilizing the liquid of Component A (blue) and Component B (red) to 70˚F to 80˚F, remove the lids of each container and stir Component B thoroughly using a "jiffy" mixer and electric drill, take care not to whip air into the mixture. Component A does not require pre-mixing.

Mix ratio is 1 part of Component A to 1 part of Component B by volume

Once started, continue the application until complete. When finished clean the equipment with M.E.K. (methyl ethyl ketone) or mineral spirits and apply a light coat of petroleum jelly to gun parts. Do not allow InstaGel Spray 40 to cure in the spray gun or reservoirs.

Apply 3/8" to ½" thickness for best results. InstaGel Spray 40 can be applied as thick as desired with no curing problems. Depending on relative humidity and temperature, parts can be handled in twelve (12) to sixteen (16) hours. Full cure is attained in 24 hours at 72˚F. Cheese cloth or open weave fiberglass cloth can be used in between sprayed on layer of the InstaGel Spray 40 to increase tear resistance of the cured rubber.

If within six (6) to eight (8) hours from the initial application, InstaGel Spray 40 can be applied with no special surface preparation, although surfaces should be clean and dry. After this period, Primer 450 adhesion promoter should be used before recoating (available from Industrial Polymers).


Working Properties

Mix Ratio By Weight

100 parts A/ 97.71 part B

Mix Ratio By Volume

100 parts A/ 100 parts B

Viscosity @ 72°F (A Side)

2250 CPS

Viscosity @ 72°F (B Side)

1000 CPS

Viscosity @ 72°F (Mixed)

500,000 CPS


Part A:



Part B:

Light Blue



Light Blue

Working Life @ 72°F

10-15 minutes

Set Time* @ 72°F

15-20 minutes

* Set time and Demold time depends on temperature and relative humidity.


Physical Properties

Specific Gravity (Part A)


Specific Gravity (Part B)


Specific Gravity (Mixed)


Weight/Gallon Part A

8.82 lbs.

Weight/Gallon Part B

8.56 lbs.

Weight/Gallon Mixed

8.69 lbs.

Cubic inch per lb. of product


Hardness @ 72° F

ASTM 2240-85

40-50 Shore A

Tear Strength

ASTM D-624

244 lb./in.

Tensile Strength

ASTM D-412 die C

1076 psi


ASTM D-412 die C



Clean Up

Dispose of all empty InstaGel 40 Spray component containers in accordance with local, state and federal regulations. Empty component containers can be rendered non-hazardous by rinsing the containers with a small amount of mixed material and allowing material to cure for 24 hours. The containers will then contain non-hazardous cured urethane.

Storage and Shelf Life

InstaGel Spray 40 liquids should be stored in the original, unopened containers in temperatures between 75˚F and 85˚F (24˚C - 29˚C). Shelf life of materials, when kept in unopened sealed containers, at the recommended storage temperature is six (6) months. Containers should not be opened until ready for immediate use. When resealing opened containers, purge with dry gas, Poly-Dry (available from Industrial Polymers). To avoid air entrapment, undue agitation of containers should be avoided.


Shipping Class: Class 55 Non-hazardous