Moisture sensitivity level

Small outline, low profile (1.0 mm), enhanced electrical performance over 2.4 GHz, JEDEC moisture sensitivity level (MSL) 3 Improved signal-to-noise ratio (> 1 GHz) compared to wire-bonded parts and low-inductance die interconnects... 

Package Size, mm I/Os Substrate Number of Passive Devices Number of Flip-Chip Number of ICs Devices Moisture Sensitivity Level... 

One of the consequences of higher soldering temperatures is that far greater attention must be paid to moisture sensitivity levels. The problem can be particularly evident in surface mount components which are encapsulated in plastic, since to a certain extent, all such packages have a tendency to absorb moisture from their surroundings. 

Performance of the package moisture sensitivity level (MSL) can be impaired by the higher temperature compatibility arising from lead-free requirements. 

Roughly, for every 10 °C (18 °F) increase in temperature, the moisture sensitivity level (MSL) degrades by one level. As such, new molding compound may have to be used for components intended for lead-free soldering in order to maintain the same MSL. Components... 

What is the moisture sensitivity level (J-STD-020) for this component ... 

Organic chip carriers Degradation can be substantial, depends on Tg of material Increased moisture sensitivity level... 

TABLE 17 Parameters Associated with IPC/JEDEC Moisture Sensitivity Level Standard J-STD-20-A... 

In addition to termination-material or compatibility issues, there are several other component material-related concerns, the most important of which is damage due to moisture uptake when processed at the higher Pb-free assembly temperatures. The most prominent defect is delamination due to warpage or popcoming, a phenomenon whereby the moisture absorbed by a component on the manufacturing floor is converted to steam when exposed to the solder reflow-temperature cycle. Many components are downgraded in moisture-sensitivity-level rating when used with lead-free process conditions. 

Internal surfactants, i.e., surfactants that are incorporated into the backbone of the polymer, are commonly used in PUD s. These surfactants can be augmented by external surfactants, especially anionic and nonionic surfactants, which are commonly used in emulsion polymerization. Great attention should be paid to the amount and type of surfactant used to stabilize urethane dispersions. Internal or external surfactants for one-component PUD s are usually added at the minimum levels needed to get good stability of the dispersion. Additional amounts beyond this minimum can cause problems with the end use of the PUD adhesive. At best, additional surfactant can cause moisture sensitivity problems with the PUD adhesive, due to the hydrophilic nature of the surfactant. Problems can be caused by excess (or the wrong type of) surfactants in the interphase region of the adhesive, affecting the ability to bond. 

One other long-term condition that takes place with relatively low level DC fields in the presence of moisture is the migration of the metal of the conductor into the plastic. This was discovered to be a common thing in the past with silver conductors and phenolic insulators. The first instance of field failures were discovered in telephone equipment. The problem can occur with other metals with phenolic and also conceivably with other plastics that are moisture sensitive and can have a solvating action on the conductor metals that they contact. Most of these type plastics should be avoided inside hermetically sealed containers with movable contacts. Vapors released from the organic plastic deposit on the contacts to produce an insulation layer leading to contact failure. 

Moisture content of drug and carrier if the drug is moisture sensitive or the carrier is subject to breakdown or spoilage from moisture levels in the drug or carrier itself, appropriate drying or other steps may be required. 

On the other hand, the high level of amide groups leads to high moisture sensitivity. There is only one producer and the number of grades is limited ... 

Lactitol. Lactitol (4-0-/ -D-galactopyranosyl-D-sorbitol), is a synthetic sugar alcohol produced on reduction of lactose, usually using Raney nickel. It can be crystallized as a mono- or di-hydrate. Lactitol is not metabolized by higher animals it is relatively sweet and hence has potential as a non-nutritive sweetener. It is claimed that lactitol reduces the absorption of sucrose, blood and liver cholesterol levels and to be anticariogenic. It has applications in low-calorie foods (jams, marmalade, chocolate, baked goods) it is non-hygroscopic and can be used to coat moisture-sensitive foods, e.g. sweets. 

With a cheaper variant—which we will simply call low-budget McMurry reaction— insensitive and inexpensive titanium powder is used as a titanium source. This avoids the use of the moisture-sensitive and expensive DME-complexed TiCl3 whose oxidation level is much too high anyway. Titanium powder needs to be slightly etched superficially with trimethylchlorosilane (which is also inexpensive) ... 

In 1987, Corey and co-workers proved that highly enantioselective reduction of ketones could be achieved by using stoichiometric borane in the presence of catalytic amounts of the oxazaborolidine 28a11 (Scheme 4.3j). Compound 28a, synthesized by heating (S)-(-)-2-(diphenylhydroxymethyl)pyrrolidine at reflux in THF with 3 equivalents of BH3 THF, shows excellent catalytic activity for the asymmetric reduction of acetophenone and other ketones. The B -methylated analog 28b was later synthesized to improve the air and moisture sensitivity associated with 28a. The third analog, 28c, with a 2-naphthyl substituent on the oxazaborolidine ring, has proven to be the best to afford the alcohol 29 with superb levels of enantioselectivity. 

Several essential properties of cristobalite have influence on its applications. They include lower density than quartz (higher volume at the same mass), purity (low catalytic effect on many polymeric systems, excellent properties in exterior coatings due to low level of iron oxide), very low moisture (no need for drying in moisture sensitive systems), pure white color, less abrasive due to filler particle morphology. 

Rubber systems do stick to many plastics well, but they are relatively moisture-sensitive. There s always a risk that they may lose their adhesive strength at high humidity levels. At temperatures above about 40°C, they turn very soft and lose their inherent strength. Pure acrylates and modified acrylates are primary materials that provide PSAs with greater moisture resistance and thermal stability. Pure acrylates above all remain sufficiently adhesive up to about 150 or for short periods 200°C. Adhesive tapes of this kind are used for masking purposes in powdercoating techniques. 

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