Page 13 - Shimadzu CFT-EX Series
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 Evaluation of the Temperature Characteristics of Toner  Fluidity Evaluation of Unvulcanized Rubber
 Heating                                                                                      Constant
                    (Rubber Compounds)


                                     oduced by forming rubber compounds (mixtur
                                                                 es of rubber and additives that pr
                                                                                     ovide specific functional
                       Rubber pr
                             oducts ar
                                  e pr
 During laser printing, toner powder, which has a particle diameter of about 5 µm, is transferred onto copy paper and   Rubber products are produced by forming rubber compounds (mixtures of rubber and additives that provide specific functional
                       characteristics) in a mold and then applying heat. Therefore, the fluidity of rubber compounds can have a major effect on molding
 heated so that it adheres to the paper. In the case of color laser printing, this process is repeated for four different   characteristics) in a mold and then applying heat. Therefore, the fluidity of rubber compounds can have a major effect on molding
 colors. If the melting temperature and melt viscosity differ for the four colors, then it could cause bleeding or poor   quality. Unformed rubber compounds change their characteristics after long storage periods, which can cause fluidity to
 adhesion in areas printed first and reduce print quality. To prevent that, the temperature characteristics associated with   deteriorate or the molding process to fail, depending on how they are stored.
 toner flow must be the same for all four colors.
                    In this case, a rubber compound was stored at ambient temperature and low temperature for 14 days and   Test Conditions
                                                                                             Test Conditions
                    28 days immediately after kneading and then the fluidity was evaluated. The results showed that the given   Test Method  Constant temperature test
 Flow Beginning Temperature and 1/2 Method Temperature for   sample could be stored at low temperatures without a significant change in fluidity, even after one month.  Die Diameter  0.5 mm
                                                                                                 Die Length
                                                                                                               1 mm
 Four Toner Colors by Constant Heating Rate Testing  Using the CFT-EX series allows evaluation of the rubber compounds storage temperatures and storage   Test Temperature  280°C
                    periods without actually having to mold any parts.                          Test Pressure  20.1 MPa
                                                                                               Preheating Time  0 sec
 The constant heating rate test was performed for all four color toners used in   Test Conditions
                                 700                                                            Sample Size    1.6 g
 the same color printer (cyan, magenta, yellow, and black).  Test Method  Constant heating rate test  600
 The constant heating rate method was used to calculate characteristic values,   Die Diameter  0.5 mm  500  Test Results
 Die Length  1 mm
 such as the softening temperature, flow beginning temperature, 1/2 method   Viscosity (Pa·s)  400  Storage Temperature  Storage Period  Viscosity (Pa·s)
 Beginning Temperature  50°C                                                                       0           395.7
 temperature, and offset temperature.  Ending Temperature  200°C  300  Ambient temperature  Ambient
                                 200                  Low temperature             Temperature     14           568.1
 Heating Rate  5°C/min                                                                            28           600.0
 1/2 method temperature  : Midpoint between flow beginning and flow ending   Test Pressure  0.98 MPa  100  0  10  15  20  25  25  30  0  395.7
      temperatures  Preheating Time  240 sec  Storage Period                        Low           14           447.5
 Offset temperature   : Temperature at flow beginning stroke plus any arbitrary   Sample Size  1 g (formed into pellets)  Temperature  28  419.3
      offset stroke                Changes in Viscosity Due to Storage Methods
 All four toner colors have very similar characteristic values. In particular, the   Test Results
 values for the three non-black colors were almost identical.  Sample  Softening  Flow Beginning  1/2 Method  1/2 Method  Evaluation of the Temperature Characteristics  Heating
 Name  Temperature (°C) Temperature (°C) Temperature (°C)  Viscosity (Pa·s)
 Ensuring that the respective temperature and fluidity characteristics are
 Cyan  76.8  105.1  132.5  248.2  of General Purpose Plastics
 approximately the same is important for maintaining the print quality of color
 Magenta  75.4  105.8  131.8  240.7
 laser printers. Therefore, CFT-EX series flowtesters serve an important role in   Yellow  76.3  104.8  133.5  285.8
 toner research and development, and quality control applications.  Black  73.8  108.5  145.9  402.4  Determining the temperature where thermoplastic resins start softening and flowing, and measuring their fluidity properties are
                       extremely important for evaluating the properties of thermoplastic resins.
 1:Cyan. R
                                                                                             Test Conditions
 2:Magenta. R       The stroke-temperature graph shows that the sample starts flowing after it exceeds the flow beginning   Test Conditions
 3:Yellow. R
 4:Black. R
                    temperature and decreases in viscosity as the temperature increases (graph slope increases). The viscosity   Test Method  Constant heating rate test
                                                                                                           Constant heating rate test
                                                                                                Test Method
                                                                                                Die Diameter   1 mm
                    can be calculated for each temperature after initial flow. To accurately determine the viscosity at each   Die Length  1 mm
 Stroke  Viscosity  temperature, the constant temperature method is recommended.              Beginning Temperature  100°C
                                                                                              Ending Temperature
                                                                                                               300°C
                                                                                                Heating Rate  5°C/min
                                                                                                Test Pressure  0.98 MPa
 1:Cyan. R
 2:Magenta. R                                                                                  Preheating Time  300 sec
 3:Yellow. R
 4:Black. R
                                                                                                Sample Size    1.2 g
                                Stroke                                Test Results
 Temperature  Temperature
 Stroke-Temperature Graph  Viscosity-Temperature Graph   1:PE. R        Sample Name  Softening  Flow Beginning  1/2 Method  1/2 Method
                                                         2:PP. R                  Temperature (°C)  Temperature (°C)  Temperature (°C)  Viscosity (Pa·s)
                                                         3:PVC. R
                                                         4:PC. R         Polyethylene  142.4  153.6    203.6    16,370
                                                                        Polypropylene  175.6  187.2    215.6    5,716
 Press-Forming Powdered Samples for Efficient Measurement  Temperature  Polyvinyl chloride  175.3  208.2  234.4  6,138
                                        Stroke-Temperature Graph        Polycarbonate  183.1  205.1    253.9    10,590
 Due to the small size of toner particles, samples could easily scatter if placed directly in the
 sample chamber or spill out from die orifices. Therefore, for samples such as these, a hand
 press and preforming die unit can be used to press them into a form that can be more easily   Cylinder Cooling Fan Improves Cycle Time for Constant Heating Rate Tests
 placed in the sample chamber. Accurate values can be measured efficiently by placing only
 one pellet in the chamber.  Constant heating rate test measurements start at a low and finish at a high temperature. The cylinder
 For thermosetting resin samples, measurements can fail due to ongoing curing during the   cooling fan can be quickly attached to the bottom of the furnace to force-cool the cylinder, which can
 time it takes to place samples in the sample chamber. Therefore, it is extremely important to   significantly shorten the cooling time.
 pelletize samples before measurement.  A piston for force-cooling the cylinder with compressed air is also available.
                                                                                                     CFT-EX Series
 12                                                                                                    Capillary Rheometer Flowtester  13
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