Formed flexible packages

Water-borne adhesives are preferred because of restrictions on the use of solvents. Low viscosity prepolymers are emulsified in water, followed by chain extension with water-soluble glycols or diamines. As cross-linker PMDI can be used, which has a shelf life of 5 to 6 h in water. Water-borne polyurethane coatings are used for vacuum forming of PVC sheeting to ABS shells in automotive interior door panels, for the lamination of ABS/PVC film to treated polypropylene foam for use in automotive instmment panels, as metal primers for steering wheels, in flexible packaging lamination, as shoe sole adhesive, and as tie coats for polyurethane-coated fabrics. PMDI is also used as a binder for reconstituted wood products and as a foundry core binder. 

The most common forms of flexible packaging are the blister package and the pouch. A blister package usually consists of a lid material and a forming film. The lid material is usually a laminate, which includes a barrier layer (e.g., aluminum foil) with a print primer on one side and a sealing agent (e.g., a heat-sealing lacquer) on the other side. 

The group of plastics known as regenerated celluloses forms a transition from the natural polymers to the completely synthetically produced plastics. As a converted natural product, regenerated cellulose foil (Cellophane) has formed the basis for the first transparent, flexible packaging for food and tobacco which contributed significantly to the development of the self service shops since the beginning of the 1920s. 

Solids The most common solid oral dosage forms are capsules and tablets. A typical solid oral dosage forms container closure system is a plastic, usually high-density polyethylene (HDPE), bottle with a screw-on or snap-off closure and a flexible packaging system such as a pouch or a blister package. A typical closure consists of a cap, often with a liner, frequently with an inner seal. If used, fillers, desiccants, and other absorbent materials are considered primary packaging components. 

Virtually all forms of flexible packaging find some use in either pharmaceutical or medical products. Pack forms include ... 

On most modern horizontal and vertical form-fill-seal equipment (see Section 9.3), seal jaws are not flat bars because these give weaker seal strengths than jaws designed with serrations. If one looks at flexible packages in the marketplace, one will find vertical and horizontal serrations as shown in Fig. 6.11. 

Polybutene-1 is a polyolefin with rather specially/niche applications. A few examples are pipes for domestic and commercial hot and cold water plumbing and heating systems. Blended with PE, it forms a two-phase stmcture which is the basis of seal peel technology (easy-opening flexible packaging). Hot water tanks are... 

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