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Global Paper Consulting

Cost Generator Paper

GPC

  1. Aptitude of the paper

    The recipe, the resulting paper structure in the paper machine and both paper surfaces are only optimized for particular use.
    For example, pose gravure and offset printing are asking completely different – even opposing – demands on the print medium paper. Therefor there is no paper which is optimized to fulfil the requirements of this both print technics. Even as identical denoted paper can heavily deviate in their process relevant properties. Unidirectional optimized paper cannot provide the same quality for both sided converting.
    For permanent conjunction of different papers –also with other materials – it is necessary that the two process relevant properties of equilibrium moisture condition and moisture dependent dimensional change like Expansion, Shrinkage, Dimension stability, are harmonized.
    Each paper type has an own price, which is causally determined by the recipe and manufacturing technology. Rotogravure paper is less expensive than offset printing paper. Wet resistant label paper is more expensive than label paper without this amenity. Who only buys paper after the price and does not ask first about the suitability for his technology will pay up to a total loss of the product or loss of an order in worst case.
    The recipe, the resulting paper structure in the paper machine and both paper surfaces are only optimized for particular use. Each paper type has an own price, which is causally determined by the recipe and manufacturing technology.
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  2. Paper errors

    The unrecognized paper errors are not covered by the standardized paper specifications. Promised paper properties are ensured and confirmed by fully automated process control and largely automated testing equipment. Paper is always produced in the stated standard humidity. A different equilibrium moisture can arise only by air shortcomings in downstream formatting or at transport.
    Paper errors are caused by errors in the technology. If this errors are not noticed by the conservative paper examination, which was introduced for trading paper more than 70 years ago, the material goes as into the market.
    Some hidden defects include
    • Sizing fluctuations in surface or mass determine the deliquescence immediately
    • Sideness (front side and backside differ in topography, capillarity, absorbency)
    • Binder impoverishment, porosity, pigment loss in the topcoat
    • Topography defects during the first hours of production after felt or screen change
    • Unrecognized local quality variations in the paper web or the paper sheet by pollution and deposition on rollers and on stringing in the paper machine
    The unrecognized paper errors are not covered by the standardized paper specifications.
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  3. Paper damages created by transport and handling

    These damages are usually immediately recognizable.
  4. Process-relevant properties

    The seven process-relevant properties are not specified. So-called identical papers – offered by the trade – can behave extremely different during processing.
    The biggest cost reduction potential is the introduction of these properties along the value chain: purchasing, order preparation, order execution, storage and transportation.
    The seven process-relevant properties are not specified. So-called identical papers – offered by the trade – can behave extremely different during processing.
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  5. Climatic conditions during transport and processing

    Paper can only be successfully processed if its equilibrium moisture condition corresponds to its fabrication and the temperature of the paper source (roll or stack) corresponds with the ambient temperature of the processing machine.
    At printing papers in Europe this is 50% relative humidity detected in stacks or rolls at 23°C.
    Even with a vapor barrier in the packaging the moisture equilibrium in each stack and each role will change irreversibly if the ambient temperature is changing.
    Temperature differences around dew point or cockling temperature – latter completely unknown in practice – activate a process of moisture migration and lead to permanent damages of the paper from the edges to the center. This cannot be undone by storage at higher temperatures.
    These costs are completely unknown at the moment.

    Temperature profiles are included in rolls and stacks. During unrolling or bow change for example the humidity condenses towards to the edge regions due to the lower temperature.
    Paper can only be successfully processed if its equilibrium moisture condition corresponds to its fabrication and the temperature of the paper source (roll or stack) corresponds with the ambient temperature of the processing machine.
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  6. Waste and losses of finished goods

    Waste and losses of finished goods by unexpected interactions with ink, varnish, glue, etc. due to different process-relevant properties.
  7. Costs for customer service and customer complaint handling