Why A 5-Layer Tube?
What Are EVAL™ Resins?
EVAL™ is the registered trademark for the ethylene vinyl alcohol (EVOH) copolymer resins manufactured and marketed by Kuraray since 1972. EVAL™ resins are characterised by their excellent processability and outstanding barrier properties. The key to this remarkable balance is the combination of the proper copolymerisation ratio of ethylene to vinyl alcohol, the carefully selected degree of polymerisation and the unique proprietary manufacturing process used in the production of EVAL™ copolymers. These unique polymers are particularly suited for food, medical, pharmaceutical, cosmetic, agricultural and industrial packaging and automotive applications.
EVAL™ resins are manufactured by Kuraray’s unique polymer technology under a strict and a continuous quality control. Technological innovations have led to an extended range of different grades of EVAL™ resins for various applications.
Molecular structure of EVAL™ resins
The EVAL™ resin is a random copolymer of ethylene and vinyl alcohol. It is a crystalline polymer that has a molecular structure represented by the following formula:
Preserving food quality
Thanks to its superior gas barrier properties, EVAL™ resin is mainly used as functional barrier in food packaging applications. Keeping oxygen out, an EVAL™ layer preserves the flavour and the quality of the food. Even in cases where the food is more stable or specially treated, such as baby milk, EVAL™ barrier properties are used to protect sensitive vitamin content.
Protecting the environment
The advantage of the excellent gas barrier properties of EVAL™ resins implies that smaller quantities of raw materials (e.g. plastic) can be used without any loss of performance and protection capacity. As a result, the packaging is lighter in weight and does not contain chemicals that cause harm to the environment. Moreover, scrap containing EVAL™ can be recovered and recycled.
Plastic fuel tanks are safe and light in weight, which results in a much better fuel economy. By including an EVAL™ layer, plastic fuel tanks have a highly effective barrier against fuel vapour permeation, ensuring that they meet the most stringent international emission standards.
A lot of major automobile manufacturers around the world have already made the change from monolayer plastic and metal to more ecological multilayer plastic fuel tanks with EVAL™.
Safeguarding the home
EVAL™ is widely used for under-floor heating systems in domestic and commercial buildings. Its barrier properties prevent oxygen from dissolving into the circulating hot water and thereby corroding the metal parts in the heating element. Multilayer pipes containing an internal protective barrier layer of EVAL™ meet the strict building standards and can provide a flexible and easy to install alternative to metal pipes.
Resisting industrial chemicals
EVAL™ resins resist oils and chemical agents, making them particularly suitable for packaging organic solvents, agricultural pesticides and all kinds of oils while keeping all the advantages of plastics. As a result, plastic containers with an EVAL™ layer allow for the safe handling of solvents and other chemical substances while protecting their integrity.
European, EC Directive and FDA Compliance
EVAL™ resins comply with the strict hygienic regulations of many European countries and with the EC Directive for food packaging. EVAL™ resins have also been approved for use in direct food contact, indirect or multilayer food contact and for retort applications under the Food and Drug Administration regulations in the USA.