Paste residue

This mechanism accounts for all characteristics of chymotrypsin action except the observed preference for cleaving the peptide bonds just past residues with large, hydrophobic side chains. Examination of the three-... 

Figure 13. Sodium (Na) content in the KNO3 paste residue after ion exchange treatment at different temperature for UST porcelain. Data from [57]...

Lonox L 5005/Kyzen East to use, mild alkaline aqueous amine blend Removal of all types of flux and paste residues from stencils 104 N/A 18-28 None to boiling 0.12... 

Organic solvents Remove adhesive and solder paste residues have a wide-process window can clean at room temperature do not oxidize or corrode metals Solvents and solvent vapors may he flammable high cost may be slow drying limits on VOCs and ozone-depleting solvents (ODSs) require explosion-proof equipment... 

Type Of Secortdaries 6% Battery Paste 94% Reaidties Zinc Plant Residues, Drosses. Smelter Residues Pb Sulphates, R>-bearing Residues, Battery Paste, Residues... 

Lonox L 5005/ Kyzen 10%-17% operating concentration Removal of a broad range of paste residues, even at room temperature compatible with organic solder protectant (OSP) coatings (operating range 26°C-60°C) 103-107 N/A 18-28 N/A N/A... 

Lonox L 5020/ Kyzen Saponifier (concentration range 5%-10%) Removal of a broad range of solder paste residues (operating range 49°C-71 C) 114-118 N/A N/A N/A N/A... 

The chairman adjourned the meeting by observing that there was no clear consensus of the pathway to cleanup past residues, which apparently is site specific. But he acknowledged the value of hearing of various experiences in dealing with this problem. 

If tape is used to mask gold fingers or other features, remove it before the commencing misprint cleaning to avoid entrapping solder beads or paste residue beneath the tape. 

Furthermore, since the tension of the screen becomes slack with repeated use, it is necessary to check it periodically. Also, the screen must be washed adequately in order to form patterns with good repeatability. In particular, the triangular openings at the boundary of the aperture pattern and the edge of the parts coated in emulsion are particularly prone to blocking with paste residue. 

A circuit test vehicle with both active and passive elements was designed (Ref 44). The passive circuits consisted of band pass filters (6 to 7 GHz range) and T-resonators (5, 10, and 15 GHz), while the active circuits included a mixer device (4 to 6.5 GHz), a VCO module and a wide-band amplifier circuit. The assemblies were tested after soldering and reflow, and again after flux/paste residues had been removed. Variations in signal transmission for two different solder pastes were observed on the passive circuit elements. For the mixer device, variation between signal transmissions for the measurements with/without paste residues was approximately 1%. 

J. Csonka-Peeren, Quantifying Parasitic Induced by No-Clean Solder Paste Residues at RF Frequencies, Proceedings of APEX 2002... 

No-dean solder pastes are hydrophobic therefore water cannot be used unless a saponifier or other clean agent also is used. No-dean paste residues on the stendl can be removed using alcohol-based cleaners or solvents. Always clean a stendl promptly after use, as dry solder paste is difficult to remove from fine apertures. Stencils will require regular underside wiping of paste residue, and an alcohol-based cleaner. 

In this test, multiple, stainless steel stencils and PCBs were prepared with the latest lead-free solder pastes available. After an hour of drying time, each stencil, in conjunction with a misprinted board, was cleaned at room temperature in spray-in-air equipment for three to six minutes (Table 2). Subsequently, cleaning tests were repeated at room temperature in ultrasonic equipment. Test substrates cleaned were visually inspected under a microscope (lOx) and tested for solder-paste residues. It was shown that all tested cleaning agents removed all lead-free solder pastes (Table 3). Differences were observed in the cleaning times for the different cleaning applications. 

Uses Surfactant to soften and dissolve printing paste residues, binders, and dye pigments from printing rollers and machine parts Consoclean FOB [Consos]... 

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