| 摘要 |
PURPOSE:To obtain a discoloration inhibitor for metals, especially silver and silver alloys sustaining its vapor phase discoloration inhibiting effect for a long term, satisfying a contact discoloration inhibiting effect, and hardly emitting foul odor by blending an organosilicon compound having a mercapto group. CONSTITUTION:An organosilicon compound having a mercapto group has a group represented by the formula (where R is alkylene), and the typical compound is silane, disiloxane or polysiloxane. Polysiloxane having a high polymn. degree and low vapor pressure produces hardly a vapor phase discoloration inhibiting effect, so it is combined with silane having high vapor pressure, or it is applied to use where a vapor phase discoloration inhibiting effect is not required. This discoloration inhibitor is effective in inhibiting the discoloration of metals, especially silver and silver alloys due to H2S, and it is diluted and coated on metals, or it is stuck to a sheet of paper, cloth or the like. |
