The most important factors influencing the quality of adhesive tape

Before proposing the above, it should be noted that quality is basically a relative category, so in choosing the adhesive tape, each consumer should seek the desired quality by comparatively measuring the following factors.

• Adhesion: The force required to separate the adhesive tape from a well-adhered surface. Its amount can be measured by a dynamometer at the defined level and compared with the reference sample.
• Film Ingredients: We have already explained this.
• Thickness: Usually the thickness of adhesive tapes used in the packaging industry is about 35 microns to 65 microns.

An important issue in this case is the uniformity of thickness at different points along the length of the strip. Non-uniformity causes unwanted rupture during consumption. For better control, according to the basic rules of quality control, different samples of cargo should be randomly selected and the amount of thickness should be controlled at different points of length. Needless to say, thickness will have a virtual measure of tolerance. Another way to control thickness is to use weight. Manufacturers usually know the heat (weight per unit area) of their adhesives. By having the heat and the length of the ring, you can easily make sure of its true thickness or length by weighing each ring.

• Type of adhesive: In packaging adhesives, it is usually polycrylic with water or chemical solvent. The second type has more quality, efficiency and price than the first type. It is also used for cold weather (goods stored and carried in the cold store) and more weights.
• The amount of traction: depends on the type and quality of the film. The elongation rate in BOPP films (the best type for producing adhesive tape) is up to 180%.يعني فيلم در شرايط متعارف پس از حدود 180% كشش پاره مي شود.
• Shear strength: refers to the resistance of the adhesive to weight. It is measured in units of minutes per minute.
• Remaining effect of adhesive on the surface: If we remove the adhesive glued on the surface after a short time, how much effect of the adhesive will remain on the surface?
• Unwind: The force required to open the adhesive from the ring, which depends on the quality of the material that is sprayed on the back of the tape for this purpose. This release coating allows the adhesive to be opened in a controlled manner. This is especially important when using carton automatic gluing machines. Adhesives that have a defective quality of the release coating or the adhesive material, or without They are difficult to control or open with a lot of noise, and today silent tapes are produced by improving the quality of the film and the release material.
• Production time: Usually the tapes must be used within a certain period after production. This time varies in different types of adhesives. To identify the remaining adhesives, you can pay attention to their color. Over time, the color becomes dull. Also, the releasing coating material loses its properties over time and the adhesive does not open easily. The expired adhesive tape is easily removed from the surface and a large part of the adhesive material remains on the surface.
• Simple microscopic information: In this case, we can refer to the analysis of the film and adhesive structure, but this operation is specialized and costly.

An easier way is to physically examine the adhesive tape with a laboratory microscope. Quality film has smooth and smooth edges. In the structure of MOPP films (where the film is stretched in one direction only during production and is not suitable for the production of adhesive tape), clear polarized structures are seen over the entire displacement surface, these structures are not present in BOPP films.
The microscopic arrangement of the coated adhesive layer in the types is of very regular and uniform quality.