Heat shrinkable film is a thermoplastic film that is stretched and oriented in the production process and heat shrinkable in the use process. The heat shrinkability of film was applied as early as 1936. At first, rubber film was mainly used to shrink and package perishable food. Nowadays, heat shrinkable technology has been developed to almost package all kinds of goods with plastic shrinkable film.

In addition, shrink packaging is also used to make shrink labels and shrink bottle caps, so that containers that are not easy to print or have complex shapes can be labeled. Recently, new application fields have been developed.

Production technology and features:

The production of heat shrinkable film usually adopts extrusion blow molding or extrusion tape casting to produce thick film, and then conduct longitudinal and transverse stretching at a high elastic temperature above the softening temperature and below the melting temperature, or only stretch and orient in one direction and not in the other direction. The former is called biaxial stretch shrinkable film, and the latter is called unidirectional shrink film. When in use, when it is greater than or close to the tensile temperature, the packaged goods can be wrapped with reliable shrinkage force.

Shrink wrap has the following advantages:

(1) Beautiful appearance, close to goods, so it is also called body fitted packaging, which is suitable for commodity packaging of various shapes;

(2) Good protection. If the inner packaging of shrink packaging is combined with the transportation packaging suspended on the outer packaging, it can have better protection;

(3) Good cleanliness, especially suitable for the packaging of precision instruments and high-precision electronic components;

(4) Good economy;

(5) Anti theft is good. A variety of foods can be packed together with a large shrink film to avoid loss;

(6) Good stability, and the goods will not stagger in the packaging film;

(7) Good transparency, customers can directly see the product content. Market development and typical applications the materials used for heat shrinkable films are mainly various thermoplastic films. Initially PVC

With the continuous development of market demand, PVC shrinkable film is gradually reduced, while various PE, PP, POF and other multi-layer coextrusion heat shrinkable films are developing rapidly and become the mainstream of the market. The market is expanding further. Experts predict that the domestic heat shrinkable film market will grow at a rate of more than 20%. The food industry is the largest market for heat shrinkable packaging. Heat shrinkable film is widely used in the packaging of all kinds of fast food, lactic acid food, beverage, small food, beer can, all kinds of wine, agricultural and sideline products, dry food, local specialties and so on. It is also increasingly used in non food fields, such as labels and bottle caps, seals, fibers and clothing, aerosol products, sporting goods, electrical products, cosmetics, pharmaceuticals, grease, detergent, stationery, toys, office supplies, kitchen supplies, daily necessities, sundries, building materials, etc.

At present, the application of heat shrinkable film in the domestic market mainly shows the following characteristics:

(1) It has been widely used in fast food, ceramic products, tea sets, mechanical parts and other fields;

(2) It is of great significance to use the combination of heat shrinkable film and vapor phase antirust technology to replace antirust oil in military machinery and hardware tools to enhance the antirust ability;

(3) Heat shrinkable film is also the protector of construction and transportation materials. It is applicable to the packaging of multiple products and the packaging with pallets, which is convenient for transportation and sales, easy to realize mechanization, save labor and material resources, and can partially replace the packaging of cartons and wooden cases;

(4) Used for labels of various PET bottled beer and beverage, which can reduce the process of removing labels and facilitate recycling;

(5) It is used to replace the bundling rope packaging of bottled beer to prevent people from being injured by the explosion of bottled beer. Customers usually first consider the specific selection mode from the cost. Heat shrinkable packaging and laminating film can usually achieve the same packaging effect.

So how to decide which kind of packaging film to choose?

Generally speaking, the main differences are the requirements for packaging patterns, the frequency of packaging, the requirements for shelf life, and the physical characteristics of the packaging itself, such as liquid, powder, granular, solid, square, etc. The following criteria help customers to choose appropriate packaging materials: the size of the food factory; Whether the service object is industrial system or retail industry; Adjustment requirements; Shelf life requirements; Anti abuse requirements; The shape of the product; Whether it is used for preservation, freezing or other environmental requirements; Consistency between packaging production company and customer culture.