Acrylic varnish

Varnish can bead on application if the paint layer is too closed. As soon as this is noticed, the still wet varnish should be wiped off immediately with white spirit. To prevent recurrence, the paint layer should be made more open by first wiping the painting with white spirit.

The matting agent in Amsterdam acrylic varnish matt consists of silicas, similar to very finely pulverised glass. If the varnish is not used, the matting agent will sink into the varnish. This varnish should always be shaken well before use until the matting agent is evenly distributed in the varnish.

Use of retouching varnish
Retouching varnish (sometimes also called intermediate varnish or pull-out varnish) is used to pick up sunken-in (matt) areas and for temporary protection (provisional final varnish) of an oil painting that is not completely dry.

Retouching varnish during the painting process
During painting, ""sunken-in"" spots can occur: the paint dulls, the intensity of the colour diminishes. This cannot be avoided and is caused by a combination of the colour used, the type and amount of thinner added and the absorption of the surface.

The amount of oil in the paint can vary from colour to colour, how much diluent is added likewise. If paint contains relatively little oil, some of which is absorbed by the surface, the colour may sink in.

Assessing the colour harmony of the painting is difficult, with the result that making the right decisions about how to continue painting is also a problem. Treating the sunken-in areas (once they are thoroughly dry to the touch) very thinly with retouching varnish restores their gloss and colour. If the sunken-in areas are very absorbent, it may be necessary to repeat the operation (after intermediate drying) before gloss and colour are restored.

The varnish dries in a few hours and leaves a porous film that is thus suitable for the adhesion of a subsequent coat of paint.

NOTE: It is very important to apply the retouching varnish very sparingly because the paint, which is not yet completely dry, may dissolve in the solvent of the varnish. Preferably apply with a spray can.

Retouching varnish as a provisional final varnish
Retouching varnish can also be applied as a provisional final varnish to give the painting an even sheen and as protection against dirt. Since the varnish is porous in a thin layer, the drying process of the paint can continue.

CAUTION: For this application, it is highly recommended to let the painting dry for at least several months. Even if the paint is hand-dry on the surface at an earlier stage, the paint underneath is certainly not yet. The solvent of the varnish penetrates the underlay and brings out the oil that is not yet dry. If this happens, the painting can remain peckish for months and contaminants such as dust will adhere to the paint.

After the paint has completely dried, a final varnish can be applied over the retouching varnish.

Our Amsterdam acrylic varnishes are also suitable as a final varnish for oil paint but have slightly different properties.

• They have a different gloss
• They are more thermoplastic
• They are more flexible

Differences between Talens Acrylic Varnishes and Painting Varnishes

• The Acrylic Varnish (gloss 114 and matt 115, for both oil and acrylic paint) is a final varnish, but does not have the same properties as the Painting Varnish (gloss 002 and matt 003).
• The Acrylic Varnish is a solution of acrylic resin in turpentine, the Painting Varnish a solution of low molecular weight resin in turpentine (in the spray can turpentine).
• Both resins do not yellow.
• The 002 is glossier than the 114, the 115 more matt than the 003 (glossy and matt varnishes of the same type can be mixed together to a desired degree of gloss).
• The matting agent in the 003 consists of waxes dissolved in the turpentine; the varnish appears crystal-clear in the bottle, but shows an egg gloss when dry.
• The matting agent in the 115 consists of silicas (compare pulverised glass); this varnish must be shaken well before use as the matting agent sinks to the bottom of the bottle. In the spray can, the matting agent for both varnishes is silicas.
• For an even (matt) sheen, a varnish containing a matting agent and applied with a brush should be spread in one direction. The Acrylic Varnish forms a more flexible film than the Painting Varnish. This is particularly important when used on acrylic paints, as these paints also form a flexible film.

Before applying a final varnish, a very thin layer of oil paint should have dried for at least six months, a normal layer one year, thick to very thick layers up to several years. If a dry oil paint layer contains a lot of oil, it is advisable to wipe the painting with white spirit before varnishing to ensure good adherence.

The matting agent in Talens Picture Varnish matt is a type of wax that is dissolved in the solvent and can 'flocculate' at low temperatures. Heating the varnish ('au bain-marie' or under a jet of hot water) dissolves the matting agent evenly and the varnish can be used again.

Damar varnish is a natural tree resin dissolved in turpentine and, of the traditional varnishes, is virtually the only one still used. Damar varnish gives a high gloss. May show signs of ageing over time, such as yellowing and cracking. Dries within a few hours.

Preparation
Make sure the paint is thoroughly dry; with thin to normal layer thickness, this takes about a year, with thicker layers several years. If a painting is to be varnished that is already several years old, the surface of the painting can first be wiped with a cloth to which some white spirit has been applied. This removes the dirt from the canvas and opens the paint skin slightly. The varnish will then adhere better.

Steps in varnishing

1. Matt and satin varnishes contain matting agents that sag in the varnish and should therefore be shaken well before use; this is to avoid gloss differences.
2. Make sure that both the painting and the varnish are at room temperature.
3. It is a good idea to lay the painting flat (generously on a piece of cardboard, plastic or newspaper).
4. Hold the spray can horizontally (do not point downwards) and spray forward so that a mist of varnish descends on the painting.

Amsterdam Acrylic Varnishes are specially formulated for a durable finish on acrylic paintings. The varnish consists of a solution of acrylic resin in turpentine and turpentine oil, is available in both glossy and matt, and once dry forms a flexible film. Amsterdam Acrylic Varnish matt is matted with silicas (pulverised glass) and must be shaken well before use. For good adhesion, it is recommended to wipe an acrylic painting with white spirit before varnishing.