Transparent blisters

The influence of variations in the film layer thickness on photo protection was investigated using uncoated nifedipine tablets. Samples of the tablets were completely covered with yellow transparent blister films of layer thicknesses ranging from 30-300 pm. The photostabilizing effect of the yellow blister film was found to increase with film layer thickness. After six hours irradiation the loss of drug content was 24% for the 30 pm films and only 6% for the 300 pm films, (Fig. 6) a substantial improvement in the photo protection of the product (21). 

Figure 6 Influence of the film thickness of yellow transparent blister films on the photostability of uncoated nifedipine tablets 20mg (Suntest CPS+, 720 W/m, UV filter). ( ) 300pm, (o) 200pm, ( ) 150 pm, ( ) 70 pm, ( ) 30 pm. Source. From Ref. 21.

Until recently, there was little evidence as to whether blister packs were as effective in preventing poisonings as child resistant closures. However, a recent study in the United Kingdom found that medications involved in poisonings were most frequently packed in containers without child resistant closures (63%) or transparent blisters (20%). Conversely, child resistant closures, foil strips, sachets and opaque blister packs had low associations with poisoning incident [17]. 

Blister Packaging n The enclosing of articles in thermoformed, transparent "blisters shaped to more or less fit the contours of the articles. The preformed blisters, usually slightly oversized to provide ample room, are made of thermoplastics such as vinyl, polystyrene, or cellulosic plastics. They are placed inverted in fixtures and loaded with the articles, and then cards coated with an adhesive are applied and sealed to the flanges between and around the blisters by means of heat and pressure. 

The initial use was as a blow moulded vessel for vegetable oil candles. However, because of its biodegradability it is of interest for applications where paper and plastics materials are used together and which can, after use, be sent into a standard paper recycling process. Instances include blister packaging (the compound is transparent up to 3 mm in thickness), envelopes with transparent windows and clothes point-of-sale packaging. 

Cellulosic They are tough, transparent, hard or flexible natural polymers made from plant cellulose feedstock. With exposure to light, heat, weather and aging, they tend to dry out, deform, embrittle and lose gloss. Molding applications include tool handles, control knobs, eyeglass frames. Extrusion uses include blister packaging, toys, holiday decorations, etc. Cellulosic types, each with their specialty properties, include cellulose acetates (CAs), cellulose acetate butyrates (CABs), cellulose nitrates (CNs), cellulose propionate (CAPs), and ethyl celluloses (EC). 

Copolymers of ethylene and norbomene exhibit excellent transparency, high moisture barrier, high strength and stiffness, and low shrinkage. In comparison to poly(ethylene) (PE) and polypropylene) (PP), they show a very low gas permeability. They are used for blister packaging in pharmacy applications and for flexible films for food packaging. Multilayer films consisting of PP outer layers and a cyclic olefin copolymer are in use. 

Blister Packs. This type of pack can be produced by heat-sealing rigid transparent or translucent film to pre-coated card but vinyl thermoformings can be welded more quickly and the welding technique is more versatile. 

Cellulose acetate forms strong, transparent films and has enjoyed many applications such as photographic film, transparent tape, and blister packaging. It can also be spun into satin fibers. Satin not only means a somewhat shiny fabric woven from cellulose acetate fiber, but also refers to something with a soft texture, which the acetate fiber has. 

Processing PCTFE is by the conventional methods (extrusion, injection, etc.) processing temperatures are high, and any degradation of PCTFE can cause severe corrosion and environmental problems. Applications include wire and cable insulation, electronic flexible printed circuits, packaging material (transparent film and sheet), pharmaceutical industry in particular strip and blister packs for tablets and capsules, etc. In the chemical industry, used as gaskets, 0-rings, valve seats, chemical tank liners, etc. 

Clear extrusion sheet grades are designed for extrusion and thermoforming applications, and like other NatureWorks PLA polymers, use conventional processing techniques and equipment. Potential uses include dairy containers, food service ware, transparent food containers, blister packs, and cold drink cups. 

Leaves with spots. Cause Leaf spots. Both bacteria and fungi cause leaf spots on begonias. Bacterial leaf spot produces small blisters that are brown with yellow margins fungi may form brown, black, or transparent spots. For control information, see Leaves with spots on page 19. 

Level 2 The skin is left to dry for 4-5 minutes between two successive coats. The second and third coats trigger more pronounced erythema and cloudy white frosting, as well as some pain and discomfort. The discomfort will last around quarter of an hour. Trauchessec " applies the solution once a week until results are achieved. The first treatment consists of only one coat, the second of two, and the third of three coats of solution. After level 2, the patient s skin feels dry and tight. The top layers of the epidermis, dried out by the solution, appear transparent but still stick to the underlying cells. Flaking occurs within 4-5 days. Locally, some areas may turn a brownish color where Jessner s solution has penetrated more deeply than anticipated. After three coats, the stratum corneum separates from the skin, there is no blistering or epidermal necrosis, and the dermis is not directly affected. 

A blister pack consists of a rigid (cardboard or other) bottom liner and a sleeve of a transparent pol5Tner material. The sleeve can either reproduce the packed article contours (blister strip pack, Fig. 2.55b) or be of regular spherical shape (blister bubble pack. Fig. 2.55c). The sleeve is produced by thermoforming and is bonded to the bottom liner by welding. For the blister pack, commonly inhibited film materials and sheets up to 0.15-1.0 mm thick are used. Mainly small-size hardware and tools are packed by this method. The blister pack adds an attractive appearance to the goods, protects reliably against various effects and enables direct observation of the contents by customers. 

The feasibility of using Raman as a non-destructive quality control method for drug product has been demonstrated for intact gel capsules, for which a spectrum could be obtained even from the capsule inside a blister pack [38], since the gel capsule and blister are transparent to the wavelength of the laser excitation. 

Polyvinylchloride is used as basic material for the production of infusion bags. It can also be found in blister packages. Polyvinylchloride is generated from the monomer vinylchloride with the help of a catalyst Pure PVC is a hard, transparent plastic. 

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