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Cheap sandpaper was often passed off as glass paper; Stalker and Parker cautioned against it in A Treatise of Japaning and Varnishing published in 1688. [5] In 1921, 3M invented a sandpaper with silicon carbide grit and a waterproof adhesive and backing, known as Wet and dry. This allowed use with water, which would serve as a lubricant to ...
Blue paper (known in Italian as carta azzurra, carta cerulea, and carta turchina) has often been used as a support for drawings and prints by artists. [1] With its inherent middle tone, blue paper is a particularly effective material for rendering the effects of three-dimensionality on a two dimensional surface.
In borosilicate glasses rich in boron, sulfur imparts a blue color. With calcium it yields a deep yellow color. [4] Manganese can be added in small amounts to remove the green tint given by iron, or in higher concentrations to give glass an amethyst color. Manganese is one of the oldest glass additives, and purple manganese glass was used since ...
The cyanotype was discovered, [2] and named thus, by Sir John Herschel who in 1842 published his investigation of light on iron compounds, [3] expecting that photochemical reactions would reveal, in form visible to the human eye, the infrared extreme of the electromagnetic spectrum detected by his father William Herschel and the ultra-violet or 'actinic' rays that had been discovered in 1801 ...
Cobalt glass—known as "smalt" when ground as a pigment—is a deep blue coloured glass prepared by including a cobalt compound, typically cobalt oxide or cobalt carbonate, in a glass melt. Cobalt is a very intense colouring agent and very little is required to show a noticeable amount of colour.
It might seem like a simple question. But the science behind a blue sky isn't that easy. For starters, it involves something called the Rayleigh effect, or Rayleigh scattering. But that same ...
Cyanotype, also referred to as "blueprinting", is the oldest non-silver photographic printing process. [1] It involves exposing materials which have been treated with a solution of potassium ferricyanide and ferric ammonium citrate to a UV light source such as the sun.
This is a list of some physical properties of common glasses. Unless otherwise stated, the technical glass compositions and many experimentally determined properties are taken from one large study. [1]