Stretch wrap film

Stretch wrap or stretch film is a highly stretchable plastic film that is wrapped around items. The elastic recovery keeps the items tightly bound. In contrast, shrink wrap is applied loosely around an item and shrinks tightly with heat.It is frequently used to unitize pallet loads but also may be used for bundling smaller items.Types of stretch film include bundling stretch film, hand stretch film, extended core stretch film, machine stretch film and static dissipative film.The most common stretch wrap material is linear low-density polyethylene or LLDPE, which is produced by copolymerization of ethylene with alpha-olefins, the most common of which are butene, hexene and octene. The use of higher alpha-olefins (hexene or octene) gives rise to enhanced stretch film characteristics, particularly in respect of elongation at break and puncture resistance.
       Other types of polyethylene and PVC can also be used. Many films have about 500% stretch at break but are only stretched to about 100 – 300% in use. Once stretched, the elastic recovery is used to keep the load tight.There are two methods of producing stretch wrap. 1) Blown: the resin is melted and blown out, it is air-cooled. This is a slower process but provides for higher quality in all the areas listed below. The cost of production is also higher due to the quantity that can be produced per hour. 2) Cast: the film is passed over cooling rollers. This makes the cooling process quick. The quality is not as good as blown but more can be produced in an hour with lower costs.Other properties such as break strength, cling, clarity, tear resistance, static discharge, etc. are also important.

Plastic Embossed 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.Plastic films are used in a wide variety of applications. These include: packaging, plastic bags, labels, building construction, landscaping, electrical fabrication, photographic film, film stock for movies, video tape, etc.Plastic films are typically formed into rolls by roll slitting. Often additional coating or printing operations are also used. Films can be modified by physical vapor deposition to make metallised films. Films can be subjected to corona treatment or can have release agents applied as needed.

Plastic films are usually thermoplastics and are formed by melting for forming the film.

• Cast – Plastics extrusion can cast film which is cooled or quenched then wound up on a roll.
• Extruded film can be stretched, thinned, or oriented in one or two directions. Blown or tubular process forces air into an extruded ring to expand the film. Flat tenter lines stretch the extruded film before annealing.
• Calender rolls can be used to form film from hot polymers
• Solution deposition is another film forming process.
• Skiving is used to scrape off a film from a solid core (sometimes used to make PTFE thread seal tape)
• Coextrusion involves extruding two or more layers of dissimilar polymers into a single film
• Lamination combines two or more films (or other materials) into a sandwich
• Extrusion coating is used to form a film onto another film or substrate

Poly embossed film in Kerala

Conventionally, a packaging material using a PVA film has been widely used as a material for containing agricultural chemicals, medicines, dyes, detergents, fertilizers, cosmetics, sanitary products and the like. This packaging material is used for, for example, obtaining a solution of what is included in the container utilizing the water solubility of PVA, by directly casting the container into an aqueous medium to allow disintegration, dispersion or dissolution of the container, for the disposal of the packaging material opened when in use, by dumping the packaging material into water as it is, and for other purposes. However, because the PVA film absorbs moisture, the surface sometimes becomes sticky and tends to show blocking of film due to the adhesive property of the film in high humidity.

To prevent the blocking property, films are generally embossed. For example, an embossed water soluble film has been proposed, which has a thickness of a concave part of 15-25 μm, and a tensile strength of the film of 2.5-4.5 kg/mm² (JP-A-7-290567).

While the above-mentioned film shows improved dispersibility and dissolution in water, mechanical strength and the like, it is otherwise with regard to resistance to blocking, appearance to impart an impression of high quality, resistance to pinholes and the like and these aspects have not been considered sufficiently.

Poly Embossed Film

The diamond shaped embossing in the film helps in the easy removal of air between the film and the rubber while calendering resulting in easy and distortion free removal of the film from the rubber. The film is used as a liner to the calendered rubber to retain the properties of rubber and also to prevent dust and other foreign matters from sticking to the rubber while calendering and during storage before taken for further processing Semi Embossed Film is used by Tyre manufacturers. Tread and Bonding Gum manufacturers, Conveyor Belt manufacturers and other Rubber Coated Fabric manufacturers Standards colours are Milky White, French Blue, Red, Yellow and Natural. However any other colour as per customer's requirement can be supplied subject to a minimum quantity order. The minimum base thickness that can be produced is 40 microns and the maximum is 150 microns. Hitech Packaging design and fabricate an array of poly embossed films that are available in our standard sizes. We are also capable of producing as per our clients' demands. These films yield better result and hence, have created huge market for themselves in the market.

Ldpe Semiembossed Film

Film Embossing Process

Film embossing is a mechanical process in which a flat film is transformed into an embossed product. During the process, thermal and stress fields are applied to the polymer, causing changes in the microstructure and physical dimensions of the material. The engineering analysis of the process requires the study of various aspects relating to the characterization of the microstructure before and after embossing, A variety of techniques were employed to characterize the properties and microstructure of the embossed film in relation to crystallinity, orientation, mechanical properties, and dimensions of the embossed films. The thermal treatment of the polymer film was shown to be the most significant factor in the process. By controlling the thermal treatment of the film, it is possible to manipulate the properties and dimensions of the embossed film. The important aspects: influencing thermal treatment include the radiation heater temperature, preheat roll temperature, line velocity, and film thickness. The initial film orientation and embossing pressure have a minor effect on the final properties of the embossed film. The main effect of the embossing pressure is on the bulk thickness of the embossed film.

  

Embossed Polythene Film

Semiembossed film

semiembossed film is used as a liner to the calendared rubber to retain the properties of rubber and also to prevent dust and other foreign matters from sticking to the rubber while calendaring and during storage. It is manufactured with 100% virgin Low Density Polyethylene. The raw material is extruded and cast on the embossed roll and cooled. It can be of any color. Milky white, French blue, Red and Yellow are standard colors. The diamond shaped embossing in the film helps in the easy removal of air between the film and the rubber. Semi embossed film is used by Tyre manufacturers, Tread and bonding gum manufacturers, conveyor belt manufacturers and other rubber coated fabric manufacturers.