Glassine is a paper product that is resistant to grease, air and water. A special manufacturing process is required to make this type of paper, and it can be expensive because a single sheet represents a great deal of work in a paper factory. There are many uses for glassine, ranging from archival protection to laboratory work. Various paper suppliers make and sell it in a range of colors.
How it is Made
To make glassine, paper pulp is beaten to break down the fibers. The pulp is pressed into molds and allowed to dry into sheets. The sheets are pressed through hot rollers in a process called calendering, which makes the fibers lie flat and in the same direction. Glassine is considered supercalendered paper, because it is subjected to the process multiple times. The end result is a very smooth product that can be used as barrier protection from many substances.
Basic glassine is almost transparent, with a neutral color. The color can be changed with the addition of dyes during the pulping process, and some companies also make opaque varieties using other additives. Many people prefer this product in its semi-transparent form, because it allows them to see what is lying underneath it.
Use in Bookbinding and Art
In bookbinding and art, glassine is a valuable tool because it can be made with a neutral potenz hydrogen (pH) level. Sheets of this paper can be used as interleaves to protect fragile books or artwork. This type of paper is often bound directly into a book to protect plates from scratches or used in archival restoration to protect the individual pages of a book from the elements. The paper used for this purpose is available in a range of sizes to meet varying needs.
Use in Laboratories
In laboratory settings, this type of paper is often used as weighing paper. Weighing paper is used when powders and other small solids are weighed, to ensure that the scale remains clean and no part of the solid escapes. Glassine is ideal for this purpose because it resists leaking and grease, and it helps prevents contamination. After weighing, the sheet can be gently folded and used as a funnel to put the substance that was weighed back into its receptacle. Weighing paper usually is meant to be disposable, so that cross contamination is avoided.
Use in Food Industry
Sheets of lightweight glassine are also often found in food service settings, such as candy stores and bakeries. A sheet of this paper prevents hand-to-food contact and keeps down the spread of grease. Boxes of disposable sheets for this purpose are available from restaurant supply houses.