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42 SMT Magazine • January 2015 por degreaser. Coupons were visually observed for cleanliness and weight changes of the cou- pons were also noted. Cleaning results are given in Table 6, showing that it removed the soils from stainless steel coupons quite well for al- most all the oils except for one. This demon- strates good degreasing efficacy of the solvent 1233zd(E). Defluxing Performance We also conducted a defluxing study with 1233zd(E) and methanol blend. The blend used is an azeotropic blend of 1233zd(E) and meth- anol so they would not segregate in a vapor degreaser. Small pieces of metal coupons with baked solder fluxes were immersed in solvent for two minutes and dried in the vapor. The ex- perimental set-up is same as mentioned before boiling solvent in beaker with condenser coils near the lip. A commercial solder was used in this test. Test results showed that the removal was good both by visual observations and gravi- metric analysis. It showed equal or better per- formance compared to another commercial sol- vent/alcohol blends. There are a number of RMA fluxes that have been cleaned with this 1233zd(E) and metha- nol blend in a vapor degreaser. These fluxes were deposited on commercial parts and then removed in a vapor degreaser using immersion and vapor rinse. The fluxes cleaned are given in Table 7 below. It has been found that the 1233zd(E)/metha- nol blend is not very effective in cleaning some of the no-clean and rosin cure fluxes. Efforts are underway to develop 1233zd(E) based solvent blends to clean these no-clean and rosin core fluxes and pastes. 1233zd(E) and alcohol blend has also shown promising results in tests as a cleaner in defluxing with aerosol spray cleaning applications [6] . Aero- sol spray is generally used in a number of cas- es especially for rework. Here the solvent blend is used in conjunction with a propellant and sprayed onto fluxed printed circuit boards. Visual observation was made, circuit boards looked vi- sually clean and gravimetric measurements con- firmed the removal of flux from the boards. Shipping and Handling Due to the higher vapor pressures and the lower boiling point of 1233zd(E) shipping and handling of solvent will be different. Solvent will be shipped in steel cylinders like refrigerant jugs with outlets fitted with liquid and vapor valves. The jugs will be under the vapor pressure of the solvent itself. Containers will be of different sizes one gallon, five gallon and higher quantities such as near one barrel size or bigger depending on cus - tomer needs. The containers are recommended to be stored under room temperature conditions. Degreaser Studies Looking at the boiling point of 1233zd(E) some users initially expressed concern that the Table 6: Soil removal from coupons using 1233zd(e). Table 7: RMA Fluxes/pastes cleaned in 1233zd(e) and methanol blend. an aLTErnaTIvE SOLvEnT WITH LOW GLOBaL WarMInG POTEnTIaL continues artiCle