The price hike was understood to be receiving support from firmer crude oil values compared with a month ago, and steady demand for naphthenic base stocks. Other naphthenic producers were heard to be evaluating market conditions to decide whether to initiate a price revision as well.

On the paraffinic side of the business, a vast majority of base oil producers had lifted prices in March. Market participants were not completely surprised that pale oil suppliers would also be considering price adjustments, given improving market conditions and climbing feedstock costs. A couple of suppliers reported sold-out positions for a number of naphthenic cuts.

In related market news, a fire and explosion at the Sonneborn Chemical Plant in Petrolia, Fairview Township, Pennsylvania, were reported by local media on March 31. The cause of the fire and explosion has not been determined yet, but they appear to have occurred near the hydrogen plant.

There were no injuries reported, and evacuation of nearby residents was not necessary because the plant does not process toxic materials, industry sources said. The facility manufactures white oils, petrolatums, and microcrystalline waxes, and existing inventory should be sufficient to cover requirements over the next several weeks even if the plant remains down for a prolonged period, sources added.

Upstream, West Texas Intermediate futures regained some of the lost territory after Kuwait said an output freeze by major oil producers would be likely even if Iran opts out. The next meeting of oil-producing countries will be taking place in Doha on April 17. The comment spurred positive sentiment even as weekly data was expected to show another record build in U.S. crude inventories. Crude oil prices remain nearly 40 percent above 12-year lows struck in mid-February.

WTI settled on the CME/Nymex at $35.89 per barrel on April 5, down $2.39 per bbl from its March 29 settlement of $38.28 per bbl.

Light Louisiana Sweet wholesale spot prices closed at $36.05 per bbl on April 4, compared with $39.94 per bbl on March 28, according to data from the U.S. Energy Information Administration.

Brent was trading at $37.87 per bbl on the CME on April 5, down $1.27 per bbl from $39.14 per bbl a week earlier.

In other market-related news, U.S. consumer confidence improved in March compared to February, as measured by The Conference Board, a New York-based research group which publishes the monthly index. The March index now stands at 96.2, up from 94.0 in February.

Historic U.S. posted base oil prices and WTI and Brent crude spot prices are available for purchase in Excel format.