Print Quality Analysis Methodology

In Article, Knowledge Base, Print Quality Analysis by Adam Dewitz0 Comments

Methodology for Print Quality Analysis Reports

 

To assist the production inkjet user community with the daunting task of paper testing Inkjet Insight, through extensive continuous testing, is producing Print Quality Analysis Reports designed to allow customers to understand and compare Key Performance Indicators (KPIs) that affect each segment of high speed production inkjet printing.

Print Quality Analysis Reports contain a segment-specific subset of the 105-point data evaluation conducted during a full Paper Print Quality Analysis. Testing is independent and unbiased providing an equal comparison of each paper when processed on a particular device using the same media and fluid types, within similar production conditions, according to quantifiable measures using densitometers, microscopes and spectrophotometers.

Reports are based on objective data measurement and never on subjective opinion or general visual assessment.

Testing Process
Paper testing used to develop the PQA Reports is conducted at a production print operation or at a device manufacturer’s facility under strict controls to ensure proper machine speed, heat and ink volume settings produce a printed sheet which is dry upon exit and free of curl, cockle or strike through (based on defined targets). The G7 methodology is applied either by pre-binding at the file level or at the machine level when available.

A purpose-made, static print quality analysis file is printed, dried for 24 hours and read with commercially available color software, spectrophotometers and print quality analysis devices such as Quality Engineering Associates (QEA). The QEA device methodology for quality readings follows ISO 13660.

To the greatest extent possible, Inkjet insight verifies machine, print heads, paper, process and overall environment is within device manufacturers’ tolerances to ensure consistent analysis across various devices, ink and paper. If any of the testing elements is not performing within market expectations, such as print head, web handling or roll stock issues, such analysis will be stopped and no data will be compiled for that run.

In order to quickly gain access to a broader array of samples, or on request of members, Inkjet Insight may perform analysis on samples submitted for review. If print samples are submitted by customers or device manufacturers for Print Quality measurement (not printed by Inkjet Insight’s technical experts) machine details such as speed and profile TAC settings, as well as sample source will be defined within the report.

While a broad array of measures is conducted, PQA reports are focused on the specific KPI’s important to each defined marked segment to make evaluation straight-forward for members. Inkjet Insight currently provides the following measures where applicable:

  • Process Color Optical Density
  • Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Chroma
  • Gamut Volume

 

Testing Methodology

There are two key components to paper testing at Inkjet Insight:

  • Inkjet Ambassadors
  • Blind testing

Inkjet Ambassadors are print sites with carefully calibrated inkjet devices used to generate print samples. We coordinate with our network of Ambassadors to gather samples across a wide range of production devices.

Samples are delivered to an independent testing lab which executes a series of measurements specified by Inkjet Insight.

Testers receive a numbered sample and are not informed of the specific paper or device that was used to generate it. A random group of samples are re-tested for additional quality control.

Our approach ensures that the highest quality samples are delivered from each device and that testing is unbiased and thorough.

Key Performance Indicators

Traditional Transaction Print

Market and Reporting Description
Traditional Transaction Print includes bills, statements, confirmations, notices and simple letter mail that has only 10-15% visual coverage of the page. Total Ink Coverage (TIC/TAC) is less than 200% and is typically centered on logos and brand elements.
This market tends to be very cost sensitive, uses primarily dye inks and uncoated papers. It is also less sensitive to color quality than Transitional Print or high-end direct mail segments.

For this market, reports are generated to compare:

  • Uncoated papers
  • Uncoated versus Inkjet treated papers
  • Inkjet Treated papers
  • Paper Key Performance Indicators

  • Process Color Optical Density
  • Average Process Color Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Transitional Print

    Market and Reporting Description

    Transitional Print sits at the intersection of Transaction Printing and Direct Mail. It is characterized by transaction documents and letter mail with more images, graphics and overall use of color. Documents in this category have 15-25% visual coverage. Total Ink Coverage (TIC/TAC) is less than 200%.
    With varied origins for these businesses, operations may be using dye or pigment depending on sensitivity to cost and color quality.

    For this market, reports are generated to compare:

  • Uncoated papers
  • Uncoated versus Inkjet treated papers
  • Inkjet Treated papers
  • Paper Key Performance Indicators

  • Process Color Optical Density
  • Average Process Color Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Chroma
  • Gamut Volume (when available)
  • Monochrome Books

    Market and Reporting Description
    Monochrome books refers to the book block for educational and other books printed in black only. Visual coverage is typically less than 15% and more commonly 10% and uses black (K) ink only rather than CMYK to produce black.
    This market relies on pigment ink to deliver higher optical density. Dye will be evaluated for this market on request.

    For this market, reports are generated to compare:

  • Uncoated papers
  • Uncoated versus Inkjet Treated papers
  • Inkjet Treated versus Inkjet Coated papers
  • Paper Key Performance Indicators

  • Black Optical Density
  • Black Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Color Books

    Market and Reporting Description
    Color books are a step below Fine Art Books but use full color. This market includes both paper book covers and book blocks. Total visual coverage ranges from 15 – 30% while Total Ink Coverage (TIC/TAC) ranges from 200 – 220.
    Like Monochrome Books, optical density and text legibility are key factors however, Color Book printers must also be concerned with Color Gamut. This market relies on pigment ink to deliver higher optical density.

    The book market has wide ranges of price sensitivity; therefore, reports are generated to compare:

  • Uncoated papers
  • Uncoated versus Inkjet Treated papers
  • Inkjet Treated versus Inkjet Coated papers
  • Paper Key Performance Indicators

  • Process Color Optical Density
  • Average Process Color Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Chroma
  • Gamut Volume (when available)
  • Direct Marketing – Self-Mailers

    Market and Reporting Description
    To make information more relevant, the category of “Direct Mail” has been broken up into several market segments that better describe the specific requirements of the applications produced. Direct Marketing – Self-Mailers includes direct advertising with middle-of-the-road color requirements.
    Visual coverage is on par or slightly higher than Transitional mail pieces at 15 to 30 percent visual coverage. Total Ink Coverage (TIC/TAC) however, is higher at 200 to 220 percent. This market segment is color sensitive and concerned with both color matching and color consistency with a wide range of price sensitivity. It relies on pigment inks to enable high ink coverage.

    For this market, reports are generated to compare:

  • Uncoated versus Inkjet Treated papers
  • Inkjet Treated papers
  • Inkjet Treated versus Inkjet Coated Papers
  • Paper Key Performance Indicators

  • Process Color Optical Density
  • Average Process Color Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Chroma
  • Gamut Volume (when available)
  • Direct Marketing – Postcards & High Color Direct Advertising

    Market and Reporting Description
    To make information more relevant, the category of “Direct Mail” has been broken up into several market segments that better describe the specific requirements of the applications produced.
    As the name implies, this segment is focused on high color direct marketing
    applications. Requirements are more demanding than most other segments with Visual Coverage at 25 to 40 percent and Total Ink Coverage (TIC/TAC) of up to 240 percent. This market relies on pigment inks to enable high ink coverage.

    Relative to inkjet production, this market is somewhat less price sensitive in its pursuit of a wide color gamut and vibrant graphic reproduction.

    For this market, reports are generated to compare:

  • Inkjet Treated papers
  • Inkjet Treated versus Inkjet Coated papers
  • Inkjet Coated Papers
  • Paper Key Performance Indicators

  • Average Process Color Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Chroma
  • Gamut Volume (when available)
  • Commercial – Marketing Collateral

    Market and Reporting Description
    Commercial-Marketing Collateral addresses applications printed on heavier paper with the highest color quality requirements. Applications may include brochures, posters, greeting cards and calendars with virtually 100 percent Visual Coverage and Total Ink Coverage (TIC/TAC) of up to 260 percent.
    To achieve these results, this market relies on pigment inks and high-end matte and gloss papers.

    For this market, reports are generated to compare:

  • Inkjet Coated Matte papers
  • Inkjet Coated Matte versus Inkjet Coated Gloss papers
  • Inkjet Coated Gloss papers
  • Paper Key Performance Indicators

  • Process Color Optical Density
  • Average Process Color Ink Strike
  • Positive Small Text Raggedness – Black Text
  • Reverse Small Text Raggedness – Black Text
  • Chroma
  • Gamut Volume (when available)
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