GAC Acrylic Specialty Polymers

GAC ACRYLIC SPECIALTY POLYMERS

GAC 100 (Product #3910)
GAC 200 (Product #3920)
GAC 400 (Product #3940)
GAC 500 (Product #3950)
GAC 700 (Product #3970)
GAC 800 (Product #3980)
GAC 900 (Product #3990)

PRODUCT DESCRIPTION

GACs can be blended with GOLDEN Acrylic Paints to extend the paint, regulate transparency, create glazes, increase gloss, reduce viscosity or improve adhesion and film integrity. The GAC polymers can also be used for binding pigment solids for various effects and surfaces. Unlike the other GOLDEN Mediums and Gels, GAC Acrylic Polymers have a minimum amount of thickeners, levelers, defoamers and surfactants to ensure good film formation.

The consistency of the GAC polymers is very fluid and thinner than other GOLDEN Mediums. GOLDEN Fluid Acrylics are slightly thicker than the GACs but will be the color line least changed in viscosity with any addition of a GAC polymer.

Each GAC product represents a unique polymer that offers specific attributes. Therefore, each GAC will have its own unique benefits and applications. Refer to the individual product description of each GAC (below) to find the proper medium to use for a particular application.

PRODUCT APPLICATION

Mixing

GAC polymers should be gently stirred or rocked back and forth prior to use, but should never be shaken, as this will incorporate significant amounts of foam which will be very difficult to eliminate. Foam can severely affect the transparency of the film causing an apparent foggy or hazy quality. When applying with a brush, use minimal agitation and force, and do not overwork, as this too will result in foaming.

Spraying

If spray application is desired, blend with GOLDEN Airbrush Medium. Start at 2 parts GAC Medium to 1 part GOLDEN Airbrush Medium. When faster drying is required, replace the Airbrush Medium with GOLDEN High Flow Medium.

Varnishing

The GAC polymers are intended for use as binders, modifiers or additives for acrylic paints. They are not intended for use as a final varnish. Golden Artist Colors manufactures two different varnish systems, Polymer Varnish and MSA Varnish (Mineral Spirit Acrylic). See the GOLDEN Varnish Information Sheets for more details.

ADDITIONAL INFORMATION

Support Induced Discoloration:

Common supports (e.g. cotton canvas, linen, masonite) contain water-extractable materials that can cause discoloration in transparent acrylic glazes. To minimize Support Induced Discoloration (S.I.D.), prime support with 2 coats of GOLDEN GAC 100 before painting with acrylic paints or mediums.

 GAC POLYMER INDIVIDUAL PRODUCT DESCRIPTIONS

Use the below descriptions to decide which attributes are best suited for a particular application:

GAC 100: Universal Acrylic Polymer / S.I.D. Blocker / Most Flexible GAC Polymer.

• This polymer is one used most universally in paint manufacturing. Artists who had used "Rhoplex" (a registered trade name) will find that this GAC most closely reflects the properties to which they were accustomed.
• The most flexible with a moderate level of tack and gloss.
• Useful for diluting and extending colors, especially when film flexibility and integrity are important characteristics.
• Wets pigment surfaces well. The most ideal for artists formulating their own paints.

GAC 200: Increases Film Hardness of Acrylic Paints / Increased Non-porous Surface Adhesion.

• The hardest and least flexible of any Golden Acrylic product. Caution is advised when using this product alone.
• Used in its pure form, it is limited to applications on rigid supports, as its lack of flexibility may lead to cracking when flexed. When used alone it needs to be applied and left to dry at a minimum temperature of 70F / 21°C.
• Ideal as an additive to acrylic paints to increase film hardness and reduce dry film tack.
• Improves adhesion to non-porous surfaces; however, some surfaces, such as glass and glazed tile, will not allow for a permanent bond
• Dries with high gloss and excellent film clarity.
• Promotes cleaner edges of hard-edge techniques. The harder paint film has less "pull" as the masking tape is removed.

GAC 400: Fabric Stiffener / Rabbit Skin Glue Alternative.

• Dries to a very hard and stiff film.
• Most useful for priming fabrics (cotton, linen, silk, etc.) when stiffness is desired.
• Used as a rabbit skin glue alternative when applied directly to raw canvas or linen. Three coats of Gesso are recommended after GAC 400 to protect natural fibers from oil penetration. 
• Allows sculpting and shaping of draped fabrics.
• Note: Optional heat setting will decrease water sensitivity but also releases low levels of formaldehyde. Adequate ventilation is recommended if choosing to heat set.

GAC 500: Self-Leveling Applications / Hard Yet Flexible / Best Isolation Coat Medium for Spray-Application.

• Unique balance of film hardness and flexibility.
• Mix 2 parts GAC 500 to 1 part High Flow Medium to produce a good spraying, fast-drying isolation coat.
• Beneficial as an additive for acrylic paints for increasing mar resistance and decreasing dry film tack, without disturbing the balance between hardness and flexibility.
• Useful when working on flexible or rigid supports.
• Offers a self leveling working quality.
• Dries to high gloss film with good clarity/transparency.
• Useful to hard-edge painters to seal masking tape for cleaner edges. Apply over masking tape. Let dry before applying an additional paint layer..

GAC 800: Reduced Crazing of Dried Films / Best for Direct Pouring.

• Most useful as an additive for acrylic paints when pours/puddles are desired. Most acrylics will craze, which is the formation of valleys that run through a pour/puddle nullifying the uniformity of the film. Such crazing is the result of shrinkage forces exerted during the drying process. GAC 800 stands alone in its resistance to such film discontinuity.
• Dries with good gloss and film flexibility, but with a slight "hazy" quality.
• Useful as a modifier when adhesion to chalky surfaces is desired.

GAC 900: Increases Launderability of Acrylic Paint.

• Designed to be used as a modifier for acrylic paints for painting on clothing. See the GOLDEN Acrylics on Fabric Application Information Sheet for more extensive information.
• Offers a soft, pliable feel and when properly heat-set, provides excellent laundering stability.
• Blend with GOLDEN Heavy Body, Matte or Fluid Acrylics for brush or screen application.
• Mix with GOLDEN High Flow Acrylics for "Tie-Dye" effects.
• Note: The heat-setting process will release low levels of formaldehyde. Adequate ventilation is recommended during heat setting.

Disclaimer

The above information is based on research and testing done by Golden Artist Colors, Inc., and is provided as a basis for understanding the potential uses of the products mentioned. Due to the numerous variables in methods, materials and conditions of producing art, Golden Artist Colors, Inc. cannot be sure the product will be right for you. Therefore, we urge product users to test each application to ensure all individual project requirements are met. While we believe the above information is accurate, WE MAKE NO EXPRESS OR IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, and we shall in no event be liable for any damages (indirect, consequential, or otherwise) that may occur as a result of a product application. 

updated 4.26.22