How long can the blue drying method be preserved (how long does it take)

1. The normal preservation time of blue-dried ancient prints is about 8 years.

2. Blue printing method is also call

How long can the blue drying method be preserved (how long does it take)

1. The normal preservation time of blue-dried ancient prints is about 8 years.

2. Blue printing method is also called iron cyanate (iron blue) printing method, and the most commonly used name is blueprint printing method. Sir John Herschel found that many iron compounds can be sensitive to light in 184 1-1842.