Wax-added films are used as exterior films of laminated steel sheets for severe can-forming use. However, one difficulty in using wax-added film laminated steel sheets is the decreased coating adhesion which accompanies wax addition. Therefore, wax addition effects on coating adhesion were investigated using the surface free energy. Results demonstrated that wax on the polyethylene terephthalate（PET）film surface decreases the dipole force component（γp）of the surface free energy. The decrease in γp of the laminated film decreases the work of adhesion between the film and the coating. X-Ray photoelectron spectroscopy analysis revealed that the decrease in γp is attributable to a decrease in the ester bonds of PET that occurs along with increase of the wax ratio on the film surface. Furthermore, the laminated steel sheet coating adhesion was found to be related to the work of adhesion between the film and the coating, suggesting that the decreased coating adhesion caused by wax addition is explainable by the decrease in γp of the laminated film caused by the increase of the wax ratio on the film surface.
Several theories have been proposed to synthesize diamond particles from graphite using a metal solvent（also called a catalyst, flux or dissolver）under high-pressure and high-temperature（HPHT）conditions. Many researchers support the “dissolution-precipitation” theory, by which graphitic carbon dissolves in molten metal and subsequently precipitates in diamond form. An alternative is Hosomi's theory: solid state nucleation occurs to form diamond crystals. This study uses confocal Raman spectroscopy to examine the crystallinity of cubic boron nitride （c-BN）contained in a single-crystal diamond matrix synthesized using HPHT method according to Hosomi's theory. We also observed theheterointerface between c-BN and the diamond matrix using transmission electron microscopy to assess the type of bonding present. Constituent elements and the local chemical bonding state were examined using electron energy loss spectroscopy. Results demonstrated that the c-BN and diamond were not bonded directly, but revealed an approx. 5-nm-thick boron-based compound（or amorphous）layer at the interface. The respective concentrations of boron in diamond and carbon in c-BN were below the detection limits, indicating no effect on the crystallinity of either material under the HPHT conditions.