![]() To take just a small sample, in 2015 banned products have included glues containing toluene, chloroform, or benzene, and sometimes in alarmingly significant proportions. Any products found not to comply with the conditions established in REACH are removed from the market through the ‘rapid alert system for dangerous non-food products’ (RAPEX) information scheme. REACH is now affecting the import and usage of a wide range of chemicals in Europe. The European regulation concerning the ‘Registration, Evaluation, Authorisation and Restriction of Chemicals’ (REACH) has introduced restrictions on toluene, chloroform and DCM with specific conditions (Table 1). In addition, DCM, even as a short-lived halogenated substance has now been shown to be ozone depleting as well. ![]() Chloroform and DCM are likely to be carcinogenic to humans according to the World Health Organization IARC evaluations. Toluene is in fact suspected of damaging the unborn child and of organ damage through prolonged exposure. It is important to emphasise that these measures have proven to be short sighted with respect to increasingly strict chemical controls worldwide. Typically the halogenated solvents chloroform and dichloromethane (DCM) are now used instead. Similarly the Montreal protocol has restricted the use of carbon tetrachloride since 1989 because of its role in depleting the ozone layer. Thus benzene, since its formal recognition as a carcinogen in the mid-twentieth century, is generally replaced by toluene. In attempts to eliminate undesirable solvents, replacement strategies often seek structurally related compounds not yet covered by the legislative and regulatory measures usually required to force action in this respect. At the other end of the polarity scale hydrocarbon solvents provide the ability to dissolve oils in extractions and perform separations, yet at the same time they are highly combustible, and their low water solubility (high logP) is linked to bioaccumulation and aquatic toxicity. Amide solvents have the high polarity required to dissolve a broad range of substrates and accelerate reactions, but this functionality often implies reproductive toxicity. ![]() The volatility of solvents permits recovery and purification of the solvent by distillation, but also creates unwanted air emissions and the risk of worker exposure. However these unfortunate consequences of solvent use are often linked to the beneficial attributes of the solvent needed for the application. Therefore the use of toxic, flammable, or environmentally damaging solvents would seem unnecessary because these characteristics have no impact on the function or progress of the system in which the solvent is applied. Despite this, the solvent is not directly responsible for the composition of a reaction product, nor is it the active component of a formulation. This can be ascribed to the large volume of solvent typically used in a reaction (especially at the purification stage) or in a formulation. For underpainting, we recommend adding Gamsol to Solvent-Free Fluid.Solvents have received much attention under the remit of green chemistry. To avoid wrinkling, apply mixtures of Solvent-Free Fluid and oil colors thinly. To ensure proper drying and prevent beading-up of paint layers, Solvent-Free Fluid should be used in moderation with oil colors – no more than 25% by volume. ![]() Made from safflower oil and alkyd resin, Gamblin Solvent-Free Fluid is non-toxic and contains no Gamsol or petroleum distillates. It has a moderately fast drying rate and increases gloss. Gamblin Solvent-Free Fluid painting medium gives oil colors more flow and transparency. Solvent-Free Gel is available in the following size: 37 ml, 150 ml. After your painting session, brushes can be further cleaned using Gamsol and/or soap and water. To paint solvent-free, we recommend Gamblin Safflower Oil for cleaning brushes while you are working. To avoid wrinkling, apply mixtures of Solvent-Free Gel and oil colors thinly. To ensure proper drying of paint layers, Solvent-Free Gel should be used in moderation with oil colors. In comparison to other solvent-free mediums, Gamblin Solvent-Free Gel supports the broadest range of painting techniques with the least compromise across color, dry time, texture and mark-making. Made from safflower oil and alkyd resin, Gamblin Solvent-Free Gel is non-toxic and contains no Gamsol or petroleum distillates. Solvent-Free Gel has a moderately fast drying rate and increases gloss. Solvent-Free Gel gives colors more flow and transparency, yet holds the shape of your brushmark. ![]() Gamblin Solvent-Free Gel is the only solvent-free painting medium that supports a broad range of painting techniques with minimal compromise. ![]()
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