Question Is plexi glass porous or non porous?

[Franticframer]

Hey all, For a solution to a framing project I was considering sandwiching a book floated on mat board up against plexi to keep the cover from opening. Will the plexi stick to the book? I have heard that plexi is porous. There is a gold seal on the front that raises concern for me.

 

[EMcBride]

I took apart a piece once with acrylic glazing and the inks had stuck to the acrylic. I'd make sure it's not touching.

 

[Jeff Rodier]

Screen printed items will stick. You can feel raise lettering on paper that is screen printed like the more expensive business card upgrade.

 

[Rob Markoff]

I have heard that plexi is porous. .

Are you are asking if acrylic is an impermeable membrane, the answer is NO. If you are asking if acrylic will prevent changes in humidity, the answer is NO.

So the question is, what is this knowledge useful for? Why would the porosity of a piece of acrylic come into play in this design scenario, especially if it is inside a frame using glass as the primary glazing material?

The op refers to "sandwiching" the book. That implies that there will be contact and pressure. I would be more concerned with ferrotyping from a smooth surface remaining under pressure with direct contact to anything, let alone a gold seal.

Also, when is a "book" a "book?" Sort of like saying today a "photograph". (Could be traditional silver based printing on fiber based paper, a resin coated photograph, an ink jet print, a dye sublimated print, etc.)

A "book" could be printed using traditional lithographic processes on rag paper, on wood pulp paper, or could be a POD (print on demand) using an ink jet process or worse yet, a xerographic process (heat infused toner based) which will surely stick to acrylic in left under direct contact and exposed to changes in heat.

Jim Miller might be able to weigh in on using Mellinex but I would also be concerned with the direct contact. It might be better to use Stabillitex. Again, Jim would be a great resource.

 

[Jim Miller]

Hey all, For a solution to a framing project I was considering sandwiching a book floated on mat board up against plexi to keep the cover from opening. Will the plexi stick to the book? I have heard that plexi is porous. There is a gold seal on the front that raises concern for me.

Acrylic is gas-permeable, and will respond to moisture. However, that may not mean what you think it means. Acrylic is a much better thermal insulator than glass, which means that 'dew point' conditions will not easily develop, and the acrylic will not readily condense moisture inside the frame.

If you are concerned about the book cover sticking to the acrylic, then it would probably stick to glass just as easily. To be safe, avoid significant pressure of any material against the cover of the book. If you construct a clear film book mount using polyester or polypropylene film, along with a proper spacer from the glazing, then the book probably would not stick to the clear film. You can find book mounting instructions in the Grumble archives, in "Mounting Objects with Clear Film" and in "The Complete Guide to Shadowboxes and Framing Objects". If you are a PPFA member, your chapter's library probably has both of those books available.