Wood stain
![]() | This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages)
|
Wood stain is a type of paint used to colour wood comprising colourants dissolved and/or suspended in a vehicle or solvent. Pigments and/or dyes are largely used as colourants in most stains.
The initial application of any paint or varnish is absorbed into the substrate similarly to stains, but the binder from a stain resides mainly below the surface while the pigment remains near the top or at the surface.
Description
Wood stain is a type of
. Coloured or stained finishes do not typically deeply penetrate the pores of the wood and may largely disappear when the finish deteriorates or is removed.Composition
Stain is composed of the same three primary ingredients as paint (pigment, solvent (or vehicle), and binder) but is predominantly vehicle, then pigment and/or dye, and lastly a small amount of binder. Much like the dyeing or staining of fabric, wood stain is designed to add colour to the substrate (wood and other materials) while leaving some of the substrate still visible. Transparent varnishes or surface films are applied afterwards. In principle, stains do not provide a durable surface coating or film. However, because the binders are from the same class of film-forming binders that are used in paints and varnishes, some build-up of film occurs.
Colourants
Pigments and/or dyes are largely used as colourants in most stains. The difference between the two is in the solubility and in the size of the particles. While dyes are molecules that dissolve into the vehicle, pigments are larger than molecules and are temporarily suspended in the vehicle, usually settling out over time. Stains with primarily dye content are said to be 'transparent', while stains with more pigment in them are said to be 'solid' (opaque); some stains may be called 'semi-solid' or 'semi-transparent', and these may be interchangeable terms, and the relative transparency or opaqueness may fall somewhere between the two extremes.
Typically, dyes will colour very fine-grained woods (such as cherry or maple) while pigments will not colour woods such as these as well. Fine-grained woods generally have pores that are too small for the pigments to settle into. As a result, usually pigment-containing stains will also include a small amount of a 'binder' which helps to adhere the pigments to the wood. A common binder would be a drying oil such as linseed oil.
Most commercial stains contain both dyes and pigments, though often in varying colours and ratios (to each other) depending on the desired colouring effect. Additionally, to some extent, the degree to which a stain will colour a particular wood may be dependent on the length of time it is left on the wood, with longer exposure times accomplishing deeper colouration. Typically a 'transparent' stain will accentuate the wood grain (as it is transparent), while a more 'solid' stain will tend to obscure the wood grain (as it is more opaque, akin to what we would usually call 'paint'). Pigments, regardless of the suspension agent, will not give much colour to very dense woods but will deeply colour woods with large pores (e.g. pine).
A combination of coffee and vinegar or water is a natural alternative to synthetic wood stain.[1]
Comparison with paint and varnish
The initial application of any paint or varnish is similarly absorbed into the substrate, but because stains contain lower amounts of binder, the binder from a stain resides mainly below the surface while the pigment remains near the top or at the surface. Stains that employ metallic pigments such as iron oxides usually are more opaque; first because
High viscosity stains
Siding stain is one variety of wood stain with very high
Gel stains are a late 20th century innovation in stain manufacturing, in that they are high-viscosity liquids and do not 'flow'. This property allows more control during application, particularly when the wood is in a vertical position, which can often cause traditional liquid stains to run, drip, or pool. Gel stains often have limited penetrating ability, as they are
Absorption
Applying stains can be very easy or very difficult depending on the type of substrate, type of stain, and the
Preparation
Thorough preparation of the wood (usually by sanding) is necessary to obtain equal absorption of the stain and thus an even finish. White stain on a bare
In certain cases it is necessary to clean the wood or remove existing stains prior to staining the wood with a commercial stain in order to avoid damaging the wood. This can be the case for both unfinished and finished wood.
Cleaning stained wood
There are special considerations when cleaning stained wood. One of the most common stains is water stains on stained wood. Techniques to remove water stains have been documented which use a hot iron to remove the water stain.
Special caution should be used when trying to remove stains from a stained wood to avoid damaging the original stain. This is especially important with antiques.
See also
References
- ^ Jones, Sarah (2017-07-26). "Staining Wood with Coffee » The DIY Hammer". The DIY Hammer. Retrieved 26 June 2019.
- ^ Dresdner, Michael. The Woodfinishing Book.
- ^ "Kitchen Cabinets: Information on finishes for wood cabinets". cabinets-q-and-a.com. Retrieved 6 April 2018.