The specific implementation of printing G7 certification

  To obtain G7 certification for a printing enterprise, it should be roughly divided into three stages: application work, preliminary preparation and implementation of certification.

  Apply for a job

  ·Application for certification

  Printing companies apply for G7 certification to the G7 certification body in the region. They can apply through the APTEC website, or they can directly contact the relevant G7 experts and the Hong Kong APTEC certification body to apply.

  ·P2P QR code and beta application

   All enterprises must apply to Hong Kong APTEC for a P2P color chart with QR Code before G7 certification. Relevant G7 experts need to provide customers with a test version of the printed sheet designated by APTEC. It is recommended that G7-approved companies should use full-sheet test sheets, i.e. folio or 4-degree open, covering a minimum area of 70% of the press.

  Preliminary preparation

  Although G7 itself is not a true ISO standard, G7 certification requires that the materials, tools, measurement conditions and methods, and observation environment involved in the certification process must meet the requirements of relevant ISO standards. Therefore, before starting the certification process, the printing enterprise must do the corresponding preliminary preparations.

  ·Ink preparation

  The inks used in G7 certification requirements must meet the corresponding ISO 2846 standard, which has made clear requirements for printing four-color inks (except for G7 GrayScale grades, which are not required, it is recommended to use up-to-standard inks)

  ·Paper preparation

  1.G7 Colorspace: The paper must have a color difference of less than or equal to 3 in the LAB value of the paper white required by GRACoL 1, SWOP 3, and SWOP 5;

  2.G7 Targeted: The color difference between the paper white and the paper white required by GRACoL 1, SWOP 3, and SWOP 5 must be less than or equal to 5. If the color difference of the LAB value is greater than 5, the applicant company should apply in the form of [Paper White Compensation Adjustment].

  ·Measuring tools

   During the implementation of G7 certification, some professional measuring instruments and measuring software are used, and these tools are used to obtain the necessary test data for the certification process.

  1. Spectrophotometer (X-Rite I1Isis, X-Rite I1IO), and the calibration report is not expired

  2. Spectrodensitometer (X-Rite 530, 528, etc.), and the calibration report is not expired

  3. Plate measuring instrument (such as X-Rtie ICPlate2 XT, etc.), and the calibration report has not expired

  4. Measurement software (X-Rite Colorport latest version)

  The instrument and software measurement settings are as follows:

  1. Standard life: D50

  2. Observation field: 2°

  3. Density response mode: T

  4. Data format: M0 (UV Included), CGATS format

  5. All color measurements must be in accordance with ISO 13655

  ·Equipment calibration

  Before the formal certification test, the printing company must carry out the necessary testing and calibration of the CTP and printing equipment, and ensure that the equipment can be produced stably and correctly.

1. CTP calibration: According to the guidelines provided by the CTP manufacturer, adjust the CTP focal length and exposure to ensure the accurate reproduction of the dot information; detect the running state of the plate washer, control the pH value of the developer, etc. within the appropriate range to ensure that the CTP plate making system is physically and stable and controllable chemical state.

  2. Printing press calibration: The printing press (including consumables) should be maintained in a stable state, and check whether its related physical and chemical parameters meet the requirements. In order to better understand and control the status of the printing press, the necessary printing press tests should be carried out. The main items to be tested are: dry density decompression test, mechanical ghosting, lifting bars, printing registration and other tests. Adjust the printing press according to the test results (if necessary, ask a printing technician to debug it) until the printing press is debugged to the best working condition.

  Observe the environment

  G7 certification requires that the viewing conditions of the printing machine meet the ISO standard. The standard viewing conditions of the printing industry are given in ISO 3664. It requires the light source for printing to meet: the color temperature reaches 5000K, and the color rendering index (CRI) is not less than 90.