There you go
Formatting is a bit wonky in the paste and copy version here, but there you go. I could have gone into more detail, but didn't due to space retstriction.
I can see clearly now – or can I?
Rebecca Pavitt
www.fineartconserve.com
Not so long ago, there were limited choices for picture frame glazing: float glass, non-glare glass, and acrylic. There are now quite a variety of options available, and it is my hope that this article will help the consumer sort through this often confusing array.
Float glass often has a green tinge, blocks less than half of Ultra Violet light and, depending on the location of the light source, reflects about 8% of visible light back at you as glare. Non-glare glass is etched on one side so that reflected light is scattered thereby reducing glare. Etching gives the glass a foggy appearance though, which can obscure the underlying artwork. Acrylic is relatively light-weight, and shatter resistant, making it a good choice for large pieces. It scratches easily (and so requires special cleaning agents), and holds static electricity, making it a poor choice for fragile media.
In the 1980’s a new, very exciting line of glass made just for artworks was marketed by Denglas. Its products included clear float glass which did not distort color, anti-reflective coating to reduce glare without obscuring the art, and UV filtering coating. Denglas is no longer produced; Tru-Vue now makes almost all high end picture framing glass.
TRU VUE GLASS PRODUCTS
• All of their glass is clear float.
• Their UV filtering coatings block 99% UV rays between 300 and 380 nm.
• Their anti-reflective coatings show fingerprints easily, so are best handled with gloves and cleaned with microfiber cloths spritzed with rubbing alcohol.
• Available in sheets up to 40 x 60 inches.
Museum Glass: UV filtering coating on one side, and glare reduction coating on both sides.
Conservation Clear: UV filtering coating on one side.
Premium Clear: No coatings. 45% UV blocked, as with regular float glass.
For situations where glare is a problem and budget a concern, Tru Vue makes etched glass. The characteristic fogged appearance increases the further the glass is from the art, so this is not a good choice for deep frames.
Conservation Reflection Control: UV filtering coating and etched surface on one side.
Reflection Control: Etched surface on one side.
ACRYLIC PRODUCTS
Generically known as acrylic sheet, much of the product used by the picture framing industry is made by Evonik Industries, with the trade name Acrylite. Acrylite products most commonly used in framing are: FF-3 plain clear, P-99 clear etched, and OP-3 with UV filtering built into the sheet (not a coating). F-33, P-99 and OP-3 are also available with an abrasion and chemical resistant coating, designated by prefix MR (marr resistant).
• Unless optically coated, acrylics reflect 8% of light (like glass)
• FF-3 and P-99 filter 66% UV light
• OP-3 products filter 98% UV light but have a slight yellow cast
• Unlike other acrylic products, MR products can be cleaned like glass
Tru Vue markets FF-3 as Premium Clear; P-99 as Reflection Control, OP-3 P 99
as Conservation Reflection Control. It does not market MR products.
UNIQUE TRU VUE ACRYLIC PRODUCTS
Optium Museum Acrylic is OP-3 MR with Tru Vue anti-reflective coating on both sides. UV filtration is, like other OP-3 products, 98%. Available in 6 mm thickness up to 72 x 120 inches.
Optium Acrylic: FF-3 MR with Tru-Vue anti-reflective coating on both sides. The combination of MR and optical coatings increases UV filtration to 93%.
• Optium products have an antistatic coating, making them safe to use with friable media like unfixed pastels. Under certain lighting conditions they can show a pink cast, so a sample should be viewed in situ before using.
• Optium products must not be cleaned with plexi-cleaner. Rubbing alcohol spritzed onto clean microfiber cloth works best.
Special thanks to Browning and Company and members of The Picture Framers Grumble who helped greatly with my research for this article.