We’re continuing with our little encyclopaedia, ‘Hahnemühle´s fabulous world of papers’, and we’ll explain the most important parameters of artist papers to you in this second part. Now that you know all about the production processes and the difference between genuine mould-made paper and Watercolour paper, you’ll learn here what paper is made of and what properties the raw materials have. And why should you know this? So you can assess the quality and suitability of the papers.
What raw materials are artist papers made of?
Cotton fibres/rags: All Hahnemühle cotton papers are marked with a small logo symbolising a cotton plant. The Terms ‘100% rags’ or ‘100% Cotton’ also appear on the label. The word ‘rags’ is the old term for the textile fibres that paper used to be made from – until pulp (wood fibres) was discovered as a raw material for paper in 1843. It was therefore customary to grind old textiles into fibres – which were known as ‘rags’. Nowadays, however, linters have replaced rags. Linters are short, valuable fibres of cotton seeds.
Tip: Paper made of cotton fibres is soft and highly resistant to ageing. As the raw material is of a high quality, you should opt for that papers for valuable works of art that you would like to sell or exhibit.
Pulp: Pulp used for Hahnemühle artist papers is high-purity alpha-cellulose. The fibres come from deciduous and coniferous species of trees. All raw materials come from certified and sustainable sources and are gently bleached. Bleaching is necessary so that the wood pigment, lignin, does not cause the paper to yellow. Our suppliers, who are represented around the world, are certified. Our raw materials carry the Forest Stewardship Council (FSC) seal, the TCF seal or the ECF seal for chlorine-free bleaching, which works without environmentally harmful chlorine compounds.
Water: Since our paper mill was established in 1584, we have been using pure spring water from the Solling mountains to produce our high-quality papers. The water is drinking water quality. More than four centuries ago, the availability of water was the most important factor in Hahnemühle choosing to settle there and, because we use the pure, soft spring water, we still produce at this very same location. Our spring water from artesian wells always has a consistent quality. Unlike river water, it doesn’t have to be chemically treated. Most of the water is collected in the production cycle and reused. Our wastewater is not contaminated with pollutants and is returned to the water cycle.
We also add glue (sizing), chalk and starch to the artist paper. We’ll explain what These ‘additives’ do using the product properties that you’ll find on the labels or in the online product descriptions of our papers.
- ‘Material-sized’ or ‘surface-sized’
- ‘Natural white’ or ‘white’
The sizing of the paper binds the fibres (rags or pulp) and makes the paper paintable. Hahnemühle has been exclusively using synthetic glues since the 1960s.
There are two types of sizing: material sizing and surface sizing. During material sizing, the glue enters the paper as an ‘ingredient’. In contrast, the glue is applied to the already dried paper surface in the case of ‘surface sizing’. You will notice the difference when correcting and using adhesive tape. You can lift paints from surface-sized papers with a damp, clean cloth or brush. Adhesive tape is easy to peel off.
Starch is used as an ‘auxiliary material’ in paper. It gives the paper the desired strength.
Chalk (calcium carbonate) is the ‘chemical buffer’ in paper and fills the spaces between the paper fibres. All papers have a pH value greater than 8. They are therefore alkaline (acid-free) and thus perfectly protected against influences that cause the paper to age.
The properties ‘acid-free’ and ‘age-resistant’ are two important attributes for first-class and, above all else, long-lasting artist papers. Hahnemühle papers are therefore classified in the highest lifespan class for papers, so you or the person buying your art can enjoy it for a long time.
And, last but not least, let’s talk about the colour of paper. You’ve surely already noticed that white paper can be different shades of white. There are hard white tones, creamy white tones, yellowish white tones and more besides.
We make distinctions between our artist papers using the Terms ‘natural white’ or ‘white’. Natural white is slightly warmer than white. What white tone you choose is entirely a matter of your personal taste. Generally speaking, you could say that a lighter white makes the colours of a work of art pop. A warmer paper tone provides softer contrasts.
Tip: Try different Hahnemühle watercolour papers in different grammages, textures, white tones and surfaces! Hahnemühle AquarellSelection is what we call our pad containing seven genuine mould-made papers and Five Watercolour papers for testing. You will also find sample cards in specialist stores. All you have to do is ask for them!