Abstract:
Improved method and apparatus (110) for particle precipitation and coating using near- or supercritical fluid conditions. A fluid dispersion (128) having a continuous phase dispersant and at least one precipitable substance therein is contacted with a supercritical fluid (SCF) antisolvent (126) so as to generate focused high frequency antisolvent sonic waves, breaking up the dispersion into extremely small droplets. The enhanced mass transfer rates between the droplets and the antisolvent causes precipitation of very small particles on the order of 0.1-10 microns. In coating processes, a turbulent fluidized flow of core particles is created using SCF antisolvent in an enclosed zone. The core particles are contacted therein at or near supercritical conditions by fluid dispersion containing a dispersant and together with a precipitable substance. The antisolvent depletes the dispersant and the substance is precipitated onto fluidized particles.
Abstract:
The present invention is directed to methods and apparatus for effectively proportioning a mixture of compressible and non-compressible fluids, wherein the resulting mixture has an almost constant density. The present invention is particularly useful for admixing supercritical fluids with polymeric coating compositions for various spray applications.
Abstract:
A method and apparatus for spraying adhesive compositions having a high solids content comprises a source of supercritical fluid diluent (22) such as supercritical carbon dioxide, a source of virgin adhesive (14), an adhesive dispenser (18) and a mixer (20) communicating with each source (14, 22) of material and with the dispenser (18). The mixer (20) includes a dynamic mixing element which agitates the viscous adhesive material allowing (56) the supercritical carbon dioxide to be effectively dispersed into the adhesive, thus forming an adhesive composition with a high solids content having a relatively low viscosity suitable for spray application of the adhesive.
Abstract:
Disclosed are methods and apparatus for spraying liquid compositions by airless spray techniques so as to obtain wider spray patterns without having to alter the construction or configuration of conventional nozzles, nozzle tips or spray guns. By means of the present disclosure, the width of a spray pattern may be changed while the spraying operation is being conducted.
Abstract:
PROBLEM TO BE SOLVED: To make it possible to produce a patterned deposition with a thermally unstable/physically changeable material. SOLUTION: This method is for producing the patterned deposition on a substrate 14 using fluid to be compressed. A delivery system 12 cooperates with a controlled environment 30, 100, 200 holding the substrates 14 therein to receive a functional material 44 precipitated from the delivery system 12 through a fluid delivery route 13. A mask 22 is so disposed near the substrate 14 as to produce the patterned deposition on the substrate 14. COPYRIGHT: (C)2004,JPO&NCIPI
Abstract in simplified Chinese:一种加压、分配、混合及形成下述混合物之方法,该混合物含有(i)一种含有高浓度至少一种固态聚合物之含溶剂组合物,其能够以液体溶液形式进行喷雾,及(ii)至少一种压缩流体作为黏度降低烯释剂,当其加入(i)中时,其量为至少足以使得该混合物之黏度,达适于输送之程度,该压缩流体于0℃温度与一大气压标准条件(STP)下为气体,其改良处包括:
于压力P下,将含溶剂组合物及至少一种压缩流体一起与至少一种具有进料温度T1之压缩流体混合,以致该至少一种压缩流体,于压力P与温度T1下,实质上为气体或超临界流体,并具有溶解度参数为0.5至4(cal/cc)1/2,于是实质上避免该固态聚合物所不期望之沈淀作用,及因而造成之设备阻塞现象。