- Nov 29, 2016 -
Yellowed paintings during the save process will inevitably be dark, this is as a result of surface oil to be oxidized. No not yet oxidized finish, clearing out the old reservoir light up light is the only way to bring back the beauty works. Cleaning solvents are commonly used:
(1) the turpentine. Old painting is weak, and the new color effect, especially with hot water heated with better results.
(2) the refining of gasoline and benzene (toluene, xylene). The resin solvent is stronger than turpentine.
(3) ethanol (alcohol) and methanol (wood alcohol). Is the strength of resin solvent.
(4) acetone and chloroform. Dissolves resin and oil reservoir. Art supply stores sell cleaning agent is usually mixed together several solvents, strong solvents should not be used. Modern oil painting using resin varnish, can be cleaned with turpentine. Older painters use domestic oil finish, requires turpentine and alcohol mix. Only acetone cleaning works as an additive used in ancient times.
(5) hydrogen peroxide. Includes many rare material of the white pigment is lead salts in air containing small amounts of hydrogen sulfide gas when hydrogen sulfide when it encounters a lead ions, chemical reactions can occur, birth nearly black solid lead, make the painting dark, hydrogen peroxide can lead sulfide oxidation as a white lead sulfate .
Cleaning method: use white cotton balls (medical stores have sales) dip cleaning detergent from a corner of the screen, circular wipe, wipe each part for not too long, so as not to damage the color layer. Cotton balls are covered with yellow light oil immediately after replacement. The first time most of the old varnish can be cleaned off, washing it a second time for stubborn parts when strong solvents can be added. Extrusion and damage caused by dirt and flies poop stain tool can be used to clear.