An overwrap or wrap is a method of sealing a contained product, typically as part of retail packaging. It is often made of

plastic film Plastic film is a thin continuous polymeric material. Thicker plastic material is often called a "sheet". These thin plastic membranes are used to separate areas or volumes, to hold items, to act as barriers, or as printable surfaces. Plast ...

(sometimes called polywrapping) or

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses, Feces#Other uses, herbivore dung, or other vegetable sources in water. Once the water is dra ...

. The wrap is applied over the bare product or can be applied over another form of

packaging Packaging is the science, art and technology of enclosing or protecting products for distribution, storage, sale, and use. Packaging also refers to the process of designing, evaluating, and producing packages. Packaging can be described as a coo ...

. It is typically used to protect products, but can be used decoratively.

Functions

An overwrap can be used for several purposes or functions: *Combine two or more smaller packages into a larger multi-pack * Keep a package or item clean * Help prevent package pilferage or premature opening of the package * Help provide a

tamper indicating Tamper-evident describes a device or process that makes unauthorized access to the protected object easily detected. Seals, markings, or other techniques may be tamper indicating. Tampering Tampering involves the deliberate altering or adulterat ...

seal * Help keep insects out of a package * Obscure a package for distribution, sale, or gifting * Help provide an

authentication Authentication (from ''authentikos'', "real, genuine", from αὐθέντης ''authentes'', "author") is the act of proving an Logical assertion, assertion, such as the Digital identity, identity of a computer system user. In contrast with iden ...

seal * Help provide grease resistance or water resistance * Keep an item, such as magazines, clean and intact during shipment; provide an address label that does not damage the item * Provide graphics, advertising, warnings, instructions, bar codes, etc. * Provide odor control by preventing odor leakage and cross-contamination.

Types of overwraps

Shrink wrap

Shrink wrap is a material made up of polymer plastic film. When heat is applied it shrinks tightly over whatever it is covering. Heat can be applied with a hand held

heat gun A heat gun is a device used to emit a stream of hot air, usually at temperatures between , with some hotter models running around , which can be held by hand. Heat guns usually have the form of an elongated body pointing at what is to be hea ...

(electric or gas) or the product and film can pass through a heat tunnel. Most

shrink film Shrink wrap, also shrink film, is a material made up of polymer plastic film. When heat is applied, it shrinks tightly over whatever it is covering. Heat can be applied with a handheld heat gun (electric or gas), or the product and film can p ...

s are

polyethylene Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bott ...

Film wrap

Plastic film Plastic film is a thin continuous polymeric material. Thicker plastic material is often called a "sheet". These thin plastic membranes are used to separate areas or volumes, to hold items, to act as barriers, or as printable surfaces. Plast ...

s, usually

polypropylene Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer Propene, propylene. Polypropylene belongs to the group of polyolefin ...

, can be wrapped around an item and attached with

adhesive Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantage ...

, PSA tape, or heat seals. Sometimes the film is in the form of a

plastic bag A plastic bag, poly bag, or pouch is a type of container made of thin, flexible, plastic film, nonwoven fabric, or plastic textile. Plastic bags are used for containing and transporting goods such as foods, produce, Powder (substance), powders, ...

which is sealed around the item.

Decorative wrap

Wraps can be either exclusively for visual appeal (decoration) or be protective in nature but encompass a decorative element such as a printed design.

Paper wrap

Kraft paper Kraft paper or kraft is paper or paperboard (cardboard) produced from chemical pulp produced in the kraft process. Sack kraft paper (or just sack paper) is a porous kraft paper with high elasticity and high tear resistance, designed for packa ...

and a variety of other papers can be used to overwrap items in a package or to overwrap a package. Some papers provide abrasion protection for packaged items. Sealing can be by adhesive, tapes, heat seals, etc. Some papers also have grease resistance or are saturated with volatile

corrosion inhibitor A corrosion inhibitor or anti-corrosive is a chemical compound added to a liquid or gas to decrease the corrosion rate of a metal that comes into contact with the fluid. The effectiveness of a corrosion inhibitor depends on fluid composition and ...

s, etc.

References

* Soroka, W, "Fundamentals of Packaging Technology", IoPP, 2002, * Yam, K. L., "Encyclopedia of Packaging Technology", John Wiley & Sons, 2009, {{packaging Packaging