Ink Opacity (or density) is the measurement of the amount of light a coating of ink allows to pass through it. Depending on the function of the label, this is measured using either a reflective or transmission densitometer.


Many label applications require a specific level of opacity.  These applications include:


  • Labels on clear materials that are applied to colored or clear surfaces. The clear areas allow what is underneath to be seen but the opaque printed areas stand out.  Examples of this would be in packaging, where the consumer can see the contents of a package but also needs to have brand identification.


  • Printing on metallic label materials where the customer desires the ink colors to not be influenced by the metallic surfaces underneath. Conversely, in some applications, the customer wants a less opaque ink so that the printed

      color is influenced by the bright metallic material, resulting in a metallic-looking ink color.


  • Double sided door/window decals with messages on both sides. These cannot have message bleed-through to the other side or it would make it difficult to read. Example of this would be a push/pull label on a glass door.


  • Barcodes on clear labels would require opaque white ink backgrounds to allow for reliable scanning of these barcodes.


  • Cover-up decals are used to re-label mistakes on packages or products without having to discard the existing label or package. Examples of this are when barcodes are incorrect on a package or when ingredients need to be amended.


These are just a few of the applications where the opacity of an ink is critical.  ALG has worked on many applications where ink or the label material MUST have the required opacity levels in order to meet the product performance requirements.


Our product managers work with our customers to determine these requirements, recommending the best label material and ink combinations to meet your opacity requirements.

In this video, you can listen in as one of our Product Mangers walks through the steps in using a Transmission Densitometer to read - and test - ink opacity.


This calibrated unit, provides a numeric value based upon the density or opaqueness of the ink that has been applied to the material.


In this example, the material itself is clear. A white layer of ink is then printed, and this ink layer must meet a numeric opacity value, confirming the product will perform as required.


ALG Labels and Graphics is a custom manufacturer of pressure sensitive labels and decals celebrating over 50 years in business.  Our focus is delivering value to our customers with responsive service, quality products and low cost production.  Our mission is to make it easy for you to do business with ALG.

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Birmingham, Alabama 35233


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