Influencing Printability in Paper Coating

2017-01-08T00:14:16+00:00 Categories: Paper Coating Chemicals|Tags: , , , , , , , , , , , |

Influencing Printability in Paper Coating The evenness of the printed image is a very important criterion for quality. The acceptance of coated paper by printers depends on its runnability in the printing process and its printability in terms of an even image that is free of defects. The printability of paper is principally determined by [...]

Testing Of Paper And Paperboard :Strength Properties :General

2012-03-14T11:19:40+00:00 Categories: Paper Testing|Tags: , , , , , , |

Strength Properties The entire spectrum of analytical methods used for the chemical testing of paper ranges from gravimetric methods to spectroscopy, electrochemical and enzymatic methods, as well as sensoric tests on taste and odour and microbiological tests. Most of the testing methods to determine the composition are destructive. The components to be determined must be [...]

Testing Of Paper And Paperboard : Basic Properties

2012-03-14T11:07:31+00:00 Categories: Paper Testing|Tags: , , , , , , |

Basic Properties The basic properties of paper include the dimensions and the mass. In the case of sheet material such as paper, the basis weight mA is determined in accordance with ISO 536 (1995). The value mA is the ratio of the mass m to the area A of a sample. m  A = A [...]

Paper Coating Machines : General

2012-03-14T12:23:08+00:00 Categories: Paper Coating Machines|Tags: , , , , , , , , , |

Paper Coating Machines Overview Coating machines are separate machines in which a previously produced dry base paper is unwound, coated, dried, and then reeled again (Fig. 7.24). In contrast to coating applicators placed on-line in a paper machine (Section 6.8), they are usu¬ally called “off-line coaters” or “OMC” (off-machine coaters).   In a paper mill, [...]

Testing Of Paper And Paperboard :Chemical Paper Testing

2012-03-14T11:45:47+00:00 Categories: Paper Testing|Tags: , , , , , , |

Composition and Chemical Paper Testing The fiber composition of paper is determined with a light microscope (fiber micros¬copy). Due to the varying fiber morphology, both the fiber raw material and the pulping process can be determined. Chemical dyeing methods are used for con¬trast enhancement and quantitative determination of fiber composition (ZM IV/ 55/74; TAPPI T [...]

Testing Of Paper And Paperboard : Tensile strength

2012-03-14T11:45:35+00:00 Categories: Paper Testing|Tags: , , , , , , |

Tensile strength and strain at rupture are determined as values characteristic of paper strength (ISO 1924, 1992). The tensile strength together with the sample width gives the tensile strength per unit width, measured in N m–1. Together with the sample thickness the tensile strength can be expressed in kPa. The tensile index results from tensile [...]

Testing Of Paper And Paperboard : Bursting Strength

2012-03-14T11:45:25+00:00 Categories: Paper Testing|Tags: , , , , , , |

The bursting strength is important in the characterization of packaging papers. The bursting strength of paper is determined in accordance with ISO 2758 (2001) and that of board in accordance with ISO 2759 (2001). In the testing instrument, the free area of the sample stretched in a circular frame is exposed to increasing pressures until [...]

Testing Of Paper And Paperboard : Tear Resistance-Elmendorf

2012-03-14T11:45:16+00:00 Categories: Paper Testing|Tags: , , , , , , |

To determine tear resistance (Elmendorf ), a sample is torn with the help of a pendulum device starting from a predetermined cut. The work required for a tear of a given length is measured. The test is described in ISO 1974 (1990). Z-directional strength refers to the ability of paper or board to resist tensile [...]

Testing Of Paper And Paperboard : Crush Resistance

2012-03-14T11:45:04+00:00 Categories: Paper Testing|Tags: , , , , , , |

The crush resistance of paper under compressive stress is measured as the short span compression strength. To prevent the sample kinking, the free span length must be very small (typically 0.7 mm). The resistance measured according to DIN 54 518 gives the ultimate crushing load per unit width. The flat crush resistance (ISO 3035, 1982) [...]

Testing Of Paper And Paperboard : Load Deformation Properties

2012-03-14T11:44:06+00:00 Categories: Paper Testing|Tags: , , , , , , |

Load Deformation Properties Not only the strength properties, tensile strength and strain to rupture can be determined in the tensile strength test (ISO 1924, 1992), but also the tensile energy absorption, TEA, which is especially important for bag paper. The TEA value repre¬sents the nonelastic portion of the deformation energy and thus that portion of [...]