Ashland was founded in 1924 as Ashland Refining Company of Ashland, Kentucky, by Paul G. Blazer. The refinery was originally set up under the guise of the Swiss Oil Company located in Lexington, Kentucky. In 1930, the nearby Tri-State Refining Company was purchased, adding 5,500 barrels per day of capacity to the company. The company continued to merge or acquire other oil companies, combining with Swiss Oil in 1936, Allied Oil in 1948, Aetna Oil in 1949, and purchasing Frontier Oil Refining and National Refining in 1950. By that time, the company began to diversify, adding petrochemicals to its portfolio with the acquisition of R. J. Brown Company in 1956 and United Carbon in 1963.
Diversification continued with the purchase of Warren Brothers in 1966, which later was to become Ashland Paving and Construction. A significant acquisition was made in 1967 when the company purchased ADM Chemical Group; whose chemical distribution business would go on to be one of the primary businesses of the company in the later part of the 20th century. In 1969, the company reorganized to form Ashland Petroleum, as well as entering into a joint venture in Coal Mining under the name Arch Mineral.
In the 1980s and early part of the 1990s, Ashland continued to expand, buying The Permian Corporation and merging it with Scurlock Oil Company in 1991 to form a subsidiary known as Scurlock Permian Corporation. In 1992, most of Unocal's chemical distribution business was acquired, making Ashland the top chemical distributor in North America. At this time, the Industrial Chemicals & Solvents (IC&S) division was established. The company's name was changed from "Ashland Oil" to the present "Ashland Inc." in 1995, which noted the reduced importance of oil in the overall business.
The late 1990s saw considerable change in the structure of the company. In 1998, the petroleum division merged with Marathon Oil to form Marathon Ashland Petroleum, LLC (MAP). Following that in 1999, Ashland agreed to sell its Scurlock Permian subsidiary to Plains All American Pipeline and the headquarters were moved from Russell, Kentucky to Covington, Kentucky, although the Russell office is still in operation as of 2007. A monumental change came in 2005, when Ashland sold its shares of the Marathon Ashland Petroleum joint venture, to Marathon Oil, effectively dissolving the remnants of their petroleum division. After the sale, the company was no longer involved in the refining or marketing of fuels. The original oil refinery in Catlettsburg, Kentucky is still in operation today and is owned and operated by Marathon. In 2006, Ashland sold APAC (the paving and construction division) to Oldcastle Materials of Dublin, Ireland.
Ashland purchased the adhesive and emulsions divisions of Air Products & Chemicals in 2008.
Ashland announced plans to acquire Hercules Inc. on July 11, 2008 for $3.3 billion On November 13, 2008, the transaction was completed.
The company currently has four wholly owned divisions, which include Distribution, Performance Materials, Valvoline, and Water Technologies.
The Distribution division provides chemicals and solvents to a variety of industrial customers. Industries served include Adhesives, Automotive, Cleaning products, Coatings, Elastomers, Inks, Paints, Personal Care, and Plastics and Plastic Molding. Ashland also operates a business called "Environmental Services" out of certain facilities. This business is engaged in temporary storage and transport of customer waste to the proper disposal facility.
Combining the Casting Solutions, Composite Polymers, and Specialty Polymers & Adhesives businesses, Performance Materials provides products for the construction, packaging, transport, marine, and metal casting industries. Twenty Nine manufacturing facilities are found in 15 countries around the world. Casting Solutions makes Foundry Binder Resins, chemicals, sleeves, and filters for the metalworking industry. The Composite Polymers business sells unsaturated polyester resins, vinyl ester resins, and gelcoats, for use in Composites. Finally, the Specialty Polymers & Adhesives business manufacturers various adhesives and resins for the transportation, aerospace, and construction industries.
In North America, Valvoline is divided into two main sections. The "Do it for me" (DIFM) business, which includes Valvoline Instant Oil Change along with the franchise business Valvoline Express Care. The "Do it yourself" (DIY) business includes a wide variety of automotive related products. Included in these are Valvoline lubricants, along with Car Brite commercial automotive appearance products, Eagle One consumer automotive appearance products, Pyroil automotive chemicals, and Zerex antifreeze. Outside of North America, the company does not have any auto care businesses, but rather focuses on selling to consumers as well as OEM manufacturers.
In the Water Technologies division, Ashland makes chemical and non-chemical water treatment products for industrial, commercial, and municipal customers. This includes wastewater treatment, pathogen control, and boiling and cooling water treatment chemicals. The business was recently expanded with the acquisition of Degussa AG's water treatment business. In late 2008 with the closure of the Hercules acquisition, the water and papers division was created with expected revenues in excess of $2 billion.