Unfortunately, lamination was once considered a viable conservation method (this is likely where lamination misconceptions originate) as it was thought to strengthen and protect fragile paper. Over time however, it was discovered that lamination is in fact destructive. Not only does the application of high heat and pressure damage documents, laminate plastics will also "off-gas," causing a chemical reaction with materials sealed inside. Furthermore, the adhesives used in lamination are typically acidic and can thus adversely affected inks, causing them to bleed beyond their edges ("halo" effect) in printed and written material. Each of these factors cause and/or accelerate the deterioration of paper documents.