Golden Open Acrylic Colour has an extended drying time, allowing you to work with your paint for longer. These colours are very versatile—they can be used directly from the tube for traditional styles and plein air painting, or for monoprinting and screenprinting.
Open colours are workable for a similar length of time as professional oil colours (up to 100 times the drying time of regular acrylic paint). Unlike oils, you can use them without any strong solvents. You can blend, soften, shade, glaze, and use fine detail, and the paint will remain workable and wet. The range has a slightly softer consistency than Golden Heavy Body paints.
As well as the opening up of possibilities with your acrylic colour, it allows the paint to remain on your palette for longer without an annoying and wasteful skin forming on the top. As with oils, thin layers of paint will dry quicker than thicker layers, so you can glaze over the top when the initial layer is dry. Thicker layers are workable for hours, and layers thicker than 1/16in will dry incredibly slowly (again, as one would also expect with oils.)
Golden paints recommend that the artist mix Open Acrylics with a Gel Medium for heavy impasto techniques (as otherwise the paint will not fully dry throughout, deeming it relatively unstable and liable to cracking over time). For deep transparent painting techniques the Open Acrylic Gel (gloss) medium will maintain colour strength whilst maintaining consistency, and for thinner glazes and washes the Acrylic Medium (gloss) will allow you to achieve a more fluid consistency, increasing flow, but not weakening the structure of the paint in the same way that adding water would.
Open Acrylic colours can be blended with Golden Acrylics and Gel Mediums to change the opacity of the colour and alter its consistency, while simultaneously increasing the drying time. It is not recommended to apply fast-drying regular acrylic colour on top of Open Acrylic colours, as it will be detrimental to the flexibility of the paint film. Instead, as with oils, work wet-on-wet or wet-on-dry, but not wet-on-semi-dry, as this will not allow the painting to dry in a proper and stable manner.
