To which fire hazard class do the following solvents belong:
a) Spirytus należy do klasy zagrożenia pożarowego B, because it is soluble in water, and its flash point is below 294 K (21°C).
b) Terpentyna nie rozpuszcza się w wodzie i ma temperaturę zapłonu 305 K (32°C). Thus, turpentine belongs to the fire hazard class A2.
c) Benzyna lakowa również nie jest wodorozpuszczałna. Its flash point is approx 312 K (39°C). Therefore, white spirit also belongs to the fire hazard class A2.
Which painting materials should not be diluted with solvents or thinners, but with the right binder?
Silicate paints should not be diluted with a solvent – water, but a fixative, that is, a binder in the form of water glass. Adding water would make the silicate paint too cold, and there would be streaks on the coating, stains and chalking.
Also, transparent coatings for wood should not be diluted with organic solvents, but a colorless binder, i.e. containing no pigments. When using organic solvents, also this material would become too thin; as a result, it would not provide sufficient protection against the effects of the weather.
What unfavorable properties do varnishes and paints exhibit, if too much solvents and thinners are added to them?
The hiding power of paints is reduced. Only very thin coatings can be obtained. This is especially evident in very poor edge coating. Strength decreases greatly, especially resistance to atmospheric agents. In addition, gloss imperfections are possible.
What are the effects of using unsuitable solvents and thinners in varnishes and paints??
Too aggressive solvents decompose varnishes and paints. If the appropriate solvents and thinners are not selected for varnishes and paints, then they will not fulfill their role and the paint or varnish cannot be mixed well. Possible coating faults, such as poor flow, insufficient gloss or softening of the underlying coating layers.
What solvents are contained in the so-called. a replacement for turpentine?
White spirit or a mixture of white spirit with other solvents is sold as a replacement for turpentine, e.g. alcohols and aromatic compounds.
For which binders can be a solvent white spirit?
White spirit can be an oil solvent, alkyd resins, cycoocukuku, bitumen and asphalt.