An archival, neutral, buffered, reconstitutable synthetic adhesive.
A co-polymer formulated specifically for the Conservation industry.
Evasol has undergone extensive accelerated aging tests by Australia's major scientific research body, the CSIRO. This has enabled it to be used in those conservation and archival environments which have long term commitments to the preservation of the National Estate. Furthermore, Evasol has passed the Photographic Activity Test (PAT), which is authorised and undertaken by Archives Australia.
The characteristic of this EVA* co-polymer molecule is that it is less susceptible to acid hydrolysis than the traditional PVA adhesives. It includes significantly less of the acid-forming polyvinyl acetate, which is present in greater quantities in PVAs, and more of polyethylene, the component in Evasol which does not form acid in either of its wet or dry state. Furthermore, the EVA molecule is made flexible by the presence of the long polyethylene co-polymer molecule. No plasticisers have been added to this formulation.
A particular feature of Evasol is its suitability for archival work, because of its neutral pH and buffering. It has a flexible film, excellent adhesion to a variety of substrates, including difficult surfaces coated with varnish, lacquer, paint, or plastic films such as PVC. It will begin to reconstitute to its white emulsion state within 10 seconds upon contact with water. It has been formulated to a pH of 6.5 - 7, and specifically buffered for use in the archival and conservation industry. Note that the pH will fall slightly over time due to unavoidable hydrolysis of minute traces of vinyl acetate in the emulsion system.
Evasol has been specially formulated to give good bonding to paper and paper board products. It has a medium open time, and this controlled drying permits a reduction in the warping or buckling of water-sensitive substrates. It may be diluted with water, or mixed with other adhesives such as starch paste or methyl cellulose, to the proportion of 10-15%, without significant loss to the initial EVA tack. Higher dilution or mix proportions may be used where other criteria, such as heavier weights of paper, or concerns of warping, are present.
|Product Name||Evasol (pronounced EE – VA – SOL)|
|Basic Resin||Ethylene vinyl acetate co-polymer (EVA*)|
|Viscosity||2000 – 3000 cps #3/6/25°C|
|Appearance||White; creamy and soft texture|
|Solids||Approximately 58 – 60%|
|Setting Speed||Medium, in temperate climate conditions|
|Film-forming temperature||Approximately 5°C|
|Film Appearance||Very slight haze; flexible film|
|Water sensitivity||Dry film will reconstitute to emulsion form|
|pH||6.5 - 7|
|Shelf Life||3 Years. Do not refrigerate. May need occasional stirring|
* This water-based co-polymer is technically named VAE, but common usage erroneously uses the variant formula name EVA.