FURNITURE VARNISH
How dangerous they are for humans and the environment
By Dr. George Dalou
Ms. Alkistis Argyri and Ms. Erasmia Andrioti
The objective purpose of this work is to identify the effects that the use of varnishes has on humans and in general on the environment. In order to do this, it is necessary to refer to the existing types of varnishes, and to the components of which they are composed (resin, solvent, catalyst and substrate). Of these components, solvents, which are volatile organic compounds, play a negative role both in human health and in the environment. However, either by taking some protective measures, or by using new technology varnishes, people can protect themselves from these effects. As a raw material, wood is of great importance to humans. Ever since man first appeared, he has been using it in a variety of ways. Even today, with the advancement of technology and the appearance of competing materials, such as polymers, cement and metals, its value as a building and decoration material has not decreased at all. This is because it is a material that is constantly reproduced by nature, has great aesthetic and architectural value, is an insulating material, does not oxidize, is easily processed and does not pollute the environment. However, wood as a living organism exhibits hygroscopicity and anisotropy in its structure, it is flammable and is attacked by fungi, insects and other microorganisms. Thus, over time, it shows a natural wear and tear, which we can eliminate or limit with various manipulations. One of them is coating with varnishes. Varnishes contain organic solvents that when inhaled cause significant problems
TYPES OF VARNISHES
Varnishes are transparent, surface coatings, consisting of a solution of colored resins in a solvent of colored resins in a solvent, and which do not completely hide the underlying surface. Varnishes work mainly as protective agents and not as coloring materials, because they create a protective film on the surface of the wood, which is impermeable. They usually consist of the resin, the solvent, the catalyst and the substrate and can be distinguished in one or two component systems. The best known and perhaps the most widespread are nitro varnishes, which are cheap, easy to use, give a beautiful appearance, dry quickly, but are sensitive, with low resistance and highly flammable. Nevertheless, they are used a lot in furniture making. other one-component varnishes are alkyd and polyurethane varnishes, which are mainly used in industrial applications.
Two-component systems consist of a resin and a monomer, which react with each other when mixed to produce an insoluble polymer, which forms the coating. The best-known two-component systems are polyurethanes, acrylics and polyesters. These systems have excellent chemical and physical properties, but their biggest drawback is that they exhibit high toxicity, which is mainly due to the catalyst they use. for indoor air pollution
This is because they contain organic solvents that when inhaled cause significant problems. These solvents can be turpentine hydrocarbons, chlorinated hydrocarbons, alcohols (methanol, ethanol), esters and ketones (acetone) and participate in the composition of varnishes with a percentage greater than 25%
which means Volatile Organic Substances and are compounds of various
of chemical composition that contain solvents with a low boiling point in their composition, are a permanent and great threat both to ourselves and to our planet. effects of organic coatings, these are great, if one considers that the emissions from their application it is the second pollutant of the atmosphere. From research carried out in the basin of Attica, it has emerged that the emissions of organic coatings participate with the rate of 28.3% in the total pollution of the atmosphere and 29.1% of this rate corresponds to The process of impact of these substances on the environment and in humans it begins after the application of varnishes. First, low-boiling co-solvents, which mainly affect the dyestuff, are evaporated. This quantity is usually much lower than the permissible upper limits. Then, their evaporation begins. According to research, these substances cause skin diseases, lacrimation, mucous membrane irritation, respiratory problems, dizziness, headaches, feeling tired and tendencies to faint and vomit. More specifically, the solvent vapors enter through the lungs. in the blood, affecting the central nervous system

For Buying Advice, Ideas & Product Support contact at +30 2310 781 422