Our manufacturing process is true craftsmanship
When we produce linseed oil, we combine the two ingredients linseed oil and pigments. Understanding and assessing different pigments and their relationship to linseed oil calls for real craftsmanship. The pigments are like individuals and behave differently when mixed with linseed oil. Primarily, it is the mechanical processing that holds the highest significance.
We use various pipe mills and rolling mills to achieve optimal effect. Above all, we want to emphasize our three-roll mill. The method of “tearing” paint i.e. levigate pigments evenly in the linseed oil is mentioned in the literature as early as the 16th century. This was a manual process until the 1840s when they started using mechanical tearing on three-roll-mills. Some of our paints are torn in modern dissolver machines, but the natural pigments need the manual roll mills in order to work properly. The torn pigment paste is dissolved with more linseed oil until the paint has the right viscosity, resembling Turkish yoghurt. The balance between linseed oil and pigments is of utmost importance to its storage qualities. Linseed oil paint should be usable for many years, provided it is stored in properly sealed cans.
When we make new nuances from our standard paint colors, the starting point is always solely based on pigments and linseed oil. Different color bases are weighed and mixed to a new color. Copenhagen Green, for example, is a mix of the color bases iron oxide black, chrome oxide green, green umber, gold ochre, iron oxide yellow and a touch of zinc white. When we make special paints, we always base the color on the customer’s own specimen; an old paint chip or an item of a specific color. Our knowledge of paint mixing enables us to make quick decisions on which bases we should use in order to reach the desired color. Linseed oil has high density and the weight per liter varies between 1.5 and 2.2 kg depending on the pigment contents. The large pigment content gives the paint unsurpassed qualities when it comes to coverage and stretch capabilities.
Raw material; pigments and linseed oil
Pigments are chemically divided into organic and inorganic compounds. The organic pigments are based on hydrocarbons and the inorganic pigments are mainly based on metals and minerals. Inorganic pigments are generally more resilient to light and air than the organic ones and work better with linseed oil. Some examples of inorganic pigments are all clay earth pigments, iron oxides, zinc oxides, titanium oxides and cobalt.
We strive to use inorganic pigments in our paints and at the same time meet the market demands for variety in colors combined with environmentally friendly products. Lately, we have found modern inorganic pigments to replace the old vivid colors based on chromium, cadmium and lead pigments. These new pigments are based on other metal compounds that are more environmentally friendly.
You can rest assured that we never replace the natural ochre, umber and terra with iron oxide pigments in similar colors. Bone char (ivory black) is still based on animal bones and cobalt blue contains real cobalt pigments.
Our linseed oil is always extracted by cold press
Pressing the oil from the linseed without heating renders a smaller yield, but in return we get a cleaner and clearer product. The newly pressed linseed oil is called cold pressed raw linseed oil and is stored for at least six months before use. During storage, mucilage falls to the bottom and the clean oil can be tapped and used. The raw oil is extremely deep penetrating as its surface tension is lower than water. No preheating of the oil is needed which makes it suitable for priming outdoors.
This oil is also used for artist paints. The raw linseed oil dries relatively slowly. In the old days, the oil was heated to shorten the drying time. This process is commonly called boiling and the product is called coldpressed boiled linseed oil.
In the boiling process we use, the oil is heated to approximately 140 degrees C and in order to make it more reactive, oxygen and metal salts are added. This oil is a little thicker than the raw oil, but it still has very good adhesion and penetration abilities. This is the oil we use as binder in our paints.
We also refine the raw linseed oil by using a very old method in which we subject the oil to sunlight and oxygen outdoors for several months. In this process, the oil oxidizes, thickens and is bleached by the sunlight. This oil type is called sun thickened linseed oil and is added to the final coat of paint in order to enhance shine, fluidity and drying.