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Decorating Information

Silk Screen Printing

Screen printing is the most common method of decorating plastic bottles. It provides a thick, even print by forcing ink through a photographically treated screen. Screen printing is low in initial cost and offers versatility of decorating effects. Flame treatment is often required prior to decoration.

Screen printing is especially economical for one color decoration and small runs. Since each color is applied in a separate pass, a label with two colors is twice as costly as a one pass label. Creative approaches to this problem utilize reverse-printing and denday (half-tones) to generate the effect of additional label colors.

Screen printing usually requires that a margin of 3/8" from the base and shoulder of the bottle be left undecorated. Multi-color seam registered decorations which require a registration cup need a margin of 5/8" from the base and shoulder. While multi-color decorations are always seam registered, seam registration is an extra cost in one color decoration.

Printable type size should be no smaller than 3 point. In reverse printing, where copy can fill-in, type size should be no smaller than 6 point. Although 360° banding can be accomplished on a special run basis, a 1/4" break is normally required in the horizontal printing area.

Oval shaped containers can be flipped for economical one color printing of front and back panels. Closures can also be screen printed on the top or the sides.

Epoxy ink can be used for protection against scratching and for use with products that may attack standard enamel inks. Ultra-violet (UV) ink is also very resistant to scratches and dries very quickly.

Special consideration must be given to the Universal Product Code when screen printing. When ordering UPC films for screen printing, a bar width reduction must be specified to allow for the ink to spread. (See UPC fact sheet in this section for more information).

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Hot Stamping

Hot stamping provides mirror quality metallic decoration on bottles, jars and closures. Foil is usually gold or silver, but other metallic colors or wood grains are available. Elegant in appearance, hot stamping is a costly decorating method.

Hot stamping can be rolled onto a container, as in the application of 360° bands, or straight stamped. Roll printing necessitates a die and a cylinder fixture, whereas straight stamping requires a die and a shroud.

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Pressure Sensitive Labelling

Pressure sensitive labeling is an economical approach to multi-color decoration. High speed productions and low tooling costs also add to the economy of this method. These labels can be made from paper or plastics such as vinyl, polypropylene, or polyethylene. A clear pressure sensitive mylar label is virtually invisible and can yield a high gloss, no label look.

Pressure sensitive labels can provide a convenient method of inventory management if labels are stocked rather than decorated bottles. Another advantage of pressure sensitive labels is that they can easily be used in conjunction with other printing methods such as hot stamping or silk screening.

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Offset Printing

Offset printing is a high speed, economical decorating method for wide mouth rigid containers such as jars, tubs and vials. Offset printing offers multi-color printing at low cost since up to five colors can be applied at one time. Initial costs (plate charges) are higher than in screen printing and the quality of the print tends to be flat by comparison. Lacquer overcoating is recommended to protect labels with large panel areas from scratching.

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Therimage Labelling

Heat-transfer preprinted labels are another cost effective decorating method for high volume packages. Labels can be printed in up to five colors, including line, half-tone, and process printing.

Special tooling such as turrets and cylinders are required for therimage labeling. Stock turrets are available for many common bottles.

Therimage labels are roto-gravure printed, yielding a low cost label with costly initial printing plate charges. Dencal labels are screen printed, yielding a higher cost label with low initial costs that is ideal for less than 100M unit runs. Both labels are applied by the same equipment and require bottle turrets and cylinders.

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Sleeve Labelling

Sleeve labels are extremely economical, especially when used with large containers or multi-color labels. Bottles must have a recessed panel area to hold the sleeve in place. Easy to apply, labels slip over the bottle neck and conform to its sides.

The main drawback with sleeve labels is that they are not a permanent label on the bottle and can be wrinkled, torn or removed. Automatic label application equipment is available.

Another type of sleeve label is the heat-shrinkable sleeve label. These sleeve labels do not require a recessed panel area. After the label is applied, the bottle is passed through a heat tunnel which shrinks the label securely to it.

Heat-shrinkable sleeve labels provide in-house versatility when a variety of labels are being used on the same container or for smaller volume applications where therimage turrets are not available.

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Transfer Pad Printing

Transfer pad printing is an especially effective decorating method for irregular shapes. Pads receive ink from a print station and selectively apply color to a particular area, regardless of the contour. Through the use of several pads in series, pad printing offers multi-color decoration at an economical cost.

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Applied Ceramic Labelling

Applied ceramic labeling is used with glass containers to permanently apply decoration which is resistant to scratching, chipping or chemical attack. Special ink is screen printed on the container and then baked on in an oven to produce a hard, wear-resistant finish.

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The Universal Product Code

In our computer age, most consumers are familiar with the bar codes on items that are scanned at the checkout line. That bar code is the Universal Product Code or UPC, a unique 12 digit identification of an individual consumer product.

Although a UPC is not legally required, each industry dictates its own requirements. For example, the grocery industry requires a UPC on all items because it is heavily dependent on the UPC for pricing and inventory control. Conversely, some professional products and products sold directly to salons do not require a UPC. In general, all products sold at the retail level require a UPC.

When a UPC is required, high standards are strictly enforced. In some cases, a non-readable UPC can cost product owners fines, concessions to retailers, and worse yet, product pulled off shelves never to be sold. Therefore, it is important to understand what is involved in the creation of a quality, readable UPC.

Anatomy of a UPC

  1. Number System Character-the first number of the UPC, this number assigned by the Uniform Code Council simply indicates the number system that is to follow.
  2. Manufacturer Identification Number-a unique 5 digit number assigned by the Uniform Code Council.
  3. Item Number-a 5 digit number assigned and controlled by the product owner.
  4. Check Character-the last number of the UPC, it is used to verify the accuracy of the entire UPC.

Important UPC Characteristics

  1. Size-the nominal size is 1.469" wide x 1.02" high. The minimum recommended size, 80% of the nominal size, is 1.175" wide x .816" high. The maximum recommended size, 200% of the nominal size, is 2.938" wide x 2.04" high. In general, larger UPC's scan better. Size may vary depending on package design and printing conditions.
  2. Contrast-the level of contrast between bars and spaces helps determine the readability of a bar code. Although many color combinations may be used, the most reliable combination is black bars with white spaces. If that combination is not feasible, an alternative combination of dark bars with light spaces is always recommended. Since the scanner uses infared light to read the bar code, the color red cannot be scanned and therefore should not be used as any part of the UPC.
  3. Quiet Zone- the required area to the left and right of the bar code free of all printing, this area prepares the scanner for the bar code that is to follow. since bar codes can be read from either direction, quiet zones are required on both ends.
  4. Bar/Space Pattern-every number has a unique pattern of bars and spaces of varying widths. Accurate printing of these patterns and their widths is essential.

UPC Tips

  1. Location-The UPC should be located in the center of the package's "natural bottom." This is determined by considering the design of the container as well as the orientation of the package graphics.
  2. Show-Through-Show-through can occur with transparent or translucent packages when the product is seen through the spaces of a bar code. This can yield a bar code unreadable and can be avoided by overlaying an opaque white background with dark bars.
  3. Truncation -Truncation is decreasing the height but not the width of a bar code. Although not recommended, truncation is sometimes necessary. manufactures should try to reduce the bar code within the established limits before cutting off the top of the bar code through truncation.
  4. Printing Methods-Different printing methods effect the image quality of a UPC in different ways and, therefore, steps must be taken to counteract any negative effects. For example, in silk screening, the occurrence of ink spread must be calculated and bar width reduction must be incorporated into the film master. Ink spread can also decrease the flexibility of size reduction of a bar code. If a bar code is reduced too much, an attempt to silk screen it will blur the bars together. This is one of the reasons why it is recommended to keep the bar code within the minimum of 80% of the nominal size.
The printing methods also affect the position of the bar code. With any method that might involve ink spread, it is best to position the bar code on its side so that the bars run in the same direction as the ink flows during the printing process. This insures that any blurring will affect bar length rather than bar width, which is more crucial to readability.

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