Glassine Paper used to protect postage stamp sheets

Despite the phonetic sound glassine has nothing at all to do with glass. Glassine is paper and is very useful and practical as well as not being very expensive. Its main use is in the food industry where it can be used to separate slices of meat and cheese and also as a wrapping medium because of its resistance to grease.

Glassine is the main component of greaseproof paper

Glassine envelopes

Glassine envelopes are used by stamp collectors to display and store postage stamps in stamp albums or singly in small glassine pockets. Glassine is a white, translucent, semi-transparent, anti-static material and does not contain chemicals of any kind.

Why use Glassine

It cheap to buy and manufacture its waterproof so is good for foodstuffs, its airproof, anti-static and its greaseproof too. It has many uses particularly for food segregation and wrapping and was even used for potato ‘chips’ packaging. Its natural color is a ‘neutral’ white which is what most people prefer (as it allows one to see the contents) but some manufacturers will make colored varieties which are generally more expensive.

Philatelists and glassine

It is ideal paper for keeping stamps (particularly rare stamps, Christmas stamps, Disney stamps or other ‘special’ stamps) in a good moisture-proof condition. Stamp hinges which are very small are used to hold stamps in position. Stamps themselves are usually an inch square but the hinges are substantially smaller and have an adhesive on one side of them allowing them to fold over and attach the stamp to the stamp album page

.Glassine and Bookbinding

Bookbinders use glassine to good effect as interleaving paper in books, and in particular for the illustrations. Glassine adhesive tape can be useful to the bookbinding expert when it is used for book repair. Bookbinders will use the glassine in sheets to protect fine art images and photographs from damage. The sheets are bound into the book giving a permanance to the protection of the ‘special’ page or art image.

Others who use Glassine

Drug manufacturers, Photographers, Pharmacists, Chemists, Butterfly collectors, Laboratory Research teams and Book restorers all used Glassine based products. There are a numerous uses for glassine ranging from artifact retrieval and food protection to drug laboratory work. Chemists use it as weighing paper (it keeps the scales clean) and prevents cross contamination. Fireworks makers use it as outer covering for firecrackers, and such like, whose product inners (usually made of cardboard) must be protected from moisture penetration. It has also found a use (unfortunately) in the illegal drug industry as it allow powdery substances to be poured and dispersed / dispensed without any residue remaining on the paper. The glassine can be easily rolled into straws and funnels for dispensing purposes.

How Glassine is made

The manufacturing process used to make glassine involves a lot of work and is called ‘calendering’. After the paper is pulped it is dried. The pulping is to break down the paper fibers before the drying begins. Drying occurs when the pulp is pressed into the sheet molds. The rolling process that follows ensures that the paper fibers are flattened and are all facing in the same direction. The paper is ‘hot’ rolled again and again to get the ‘glassy’ effect combined with the smooth surface and thinness required. Paper rolled several times is identified as ‘super-calendered’. A balance has to be struck between the number of rollings and the flimsyness of the finished goods. Various scaling factors are used to determine the quality of the finished paper and its intended use. Each time the paper is rolled adds to the cost.