Para tertiary butylphenol formaldehyde resin also known as p-tert-butylphenol-formaldehyde resin (PTBP-FR) or 4-(1,1-dimethylethyl) phenol (PTBP Formaldehyde) is a phenol-formaldehyde resin found in commercial adhesives, and in particular in adhesives used to bond leather and rubber. It has broad usage in a large variety of industries and can be found in many household items and textile products, and in particular it is used in the manufacture of shoes.[1][2]