 PRODUCT INFORMATION SHEET
CALCIUM DRIERS Product Description Acts as a drier for oil colours and mediums. Product Code: 011 Constituents: Calcium Octoate, White Spirit Product Application Added to oil and alkyd colours to increase the rate of drying. Oils ‘dry’ or harden to an tough, insoluble film by absorbing oxygen. Calcium Driers are known as ‘through-film’ siccatives (driers), accelerating the drying of the oil body. They are not ‘surface-active’ siccatives and do not perform as surface driers. Calcium driers made from calcium octoate are recommended siccatives for artists oil colours and mediums as their addition in the correct proportion has a minimal effect regarding darkening and embrittlement of the paint film. Driers made from lead and manganese are to be avoided as they promote darkening and loss of flexibility. However, even Langridge Calcium Driers are to be used sparingly as its over-use will destroy paint films. It is recommended that Calcium Driers should be added to an oil medium or artists’ drying oil rather than mixed directly into the oil paint. Measuring quantities of driers directly into small amounts of colour is difficult and prone to miscalculation. Langridge recommends addition to mediums and oils to reduce the likelyhood of over use and to simplify the artists’ studio practise. Once mixed with an oil or medium, the artist can dispense with concerns about constant ongoing additions of driers. Add Calcium Driers as an approximate 1% addition. (i.e. To 500ml of Linseed Oil add 5ml of Calcium Drier.) Shake or stir well together. General guide to drying rates using Langridge Calcium Driers:
ADDITIONAL PRODUCT INFORMATION Problems with ambient temperature and humidity. Because artists drying oils (oils that dry to a hard, non-reversable film) absorb oxygen to harden, so the ambient temperature and humidity have an effect on the speed and success of film hardening. Oils, oil paints and oil mediums should not be applied in temperatures below 10 deg. F or above 40 deg. F. Relative humidity level should not exceed 50%. Moisture in a high humidity environment will create a fine layer of water on top of the paint film preventing oxygen from being absorbed. This will dramatically slow the hardening of the oil, potentially weakining the paint film even when fully dry. Temperature and relative humidity can be controlled in the artists studio with heating/cooling devices and the use of dehumidifying devices. Accelerating the drying rate of a completed painting. Calcium Driers should not be applied to a painting to accelerate the drying of an already laid paint film. If a painting is taking longer to dry than is expected, it is recommended to place the artwork in a dry, warm, dust-free area with a steady airflow across the surface. Once paint has been applied to a painting no attempt should be made to add driers or rapid drying mediums on top to accelerate drying. This can lead to cracking and potential flaking of the paint film. Accelerating the drying rate of varnishes. Calcium Driers cannot speed the drying of artists’ varnishes as they contain no oil. Artists’ varnishes dry by evaporation of the solvent. If a varnish remains tacky for longer than is recommended by the manufacturer, this may be due to latent solvent trapped in the preceding paint film. As it attempts to evaporate through the surface it will solubilize the resin of the varnish. Place the artwork in a dry, warm, dust-free area with a steady airflow across the surface. WORKING PROPERTIES Thinning Appearance Clean Up Available in:
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