{
    "protocol": "The hydrophilic polymer for the anti-fog layer can be synthesized by choosing a polymer such as polyvinyl alcohol, polyvinyl acetal, polyvinyl acetate, polyvinylpyrrolidone, polyethylene oxide, polyacrylamide, polyester, polyurethane, cellulose acetate, hydroxyethyl cellulose, hydroxymethyl cellulose, or gelatin, or blends or copolymers thereof. The hydrophilic polymer can be a polymer having a backbone and hydrophilic segments covalently bonded to the backbone. The synthesis can include introducing hydrophilic segments which may comprise alkylene oxides, lactones, lactams, silanes, acrylamides, alcohols, or combinations thereof. The polymer should be formed such that the hydrophilic segments comprise at least about 1 wt% to about 95 wt% by weight of the hydrophilic polymer. The resulting hydrophilic polymer can be incorporated into an anti-fog layer that might also contain an adhesive polymer and a hard polymer, ensuring that all polymers in the composition are different.Coating compositions for the adhesive layer were coated onto C-treated FEP substrates and dried at 93 degrees Celsius for 10 minutes. Each adhesive coated FEP sheet was laminated to a PVC sheet with the adhesive layer in between. Lamination was done at a foot press at 40 psi at 121 degrees Celsius or with a hand roller at room temperature. Some composites were additionally cured at 107 degrees Celsius for various time periods. Peel strength between the FEP and PVC sheets was determined using an Instron following ASTM D1876.Two FEP sheets, C-treated on both sides, are coated on both sides with Adhesive 4 and dried at 93 degrees Celsius for 10 minutes. Each adhesive coated FEP sheet is laminated between two PVC sheets with a hand roller at room temperature, followed by 5 minutes of curing at 107 degrees Celsius. Anti-fog coating compositions as detailed in Table 3 are then coated on Composites B1 and B2 over the surface of one of the PVC layers, and also applied directly to a stand-alone C-treated FEP sheet.The synthesis of hydrophilic polymers involves creating a polymer with a backbone and hydrophilic segments covalently bonded to it. Specifically, the hydrophilic polymer may be a hydrophilic polyurethane which includes hydrophilic segments such as alkylene oxides, lactones, lactams, or combinations thereof. The hydrophilic polymer should be present in the composition in an amount within a range of about 10 wt% to about 90 wt% based on the total dry weight of the anti-fog coating composition.The hydrophilic polymer comprises a polymer having a polyurethane backbone and hydrophilic segments covalently bonded to the polyurethane backbone wherein the hydrophilic segments comprise alkylene oxides, lactones, lactams, or combinations thereof."
}