Bleaching history

This morning, while using bleach to clean a sink, I realised I knew nothing about the history of this very useful, cheap product.   This article reminds us that making fabrics white used to be a very laborious process:

Humans have been whitening fabrics for centuries; ancient Egyptians, Greeks, and Romans bleached materials. As early as 300 B.C. , soda ash, prepared from burned seaweed, was used to clean and whiten cloth. During the Middle Ages, the Dutch perfected the bleaching of fabrics in a process called crofting, whereby fabrics were spread out in large fields for maximum sunlight exposure. Textile mills as far away as Scotland shipped their material to the Netherlands for this bleaching. The practice quickly spread throughout Europe, and bleaching fields were documented in Great Britain as early as 1322. In 1728 a bleaching company using Dutch methods went into business in Galloway, Scotland. In this process, the fabrics were soaked in a lye solution for several days, then "bucked," or washed clean. The fabrics were then spread out on the grass for weeks at a time. This process was repeated five or six times until the desired whiteness was achieved. Next, the fabric was treated with sour milk or buttermilk, and again bucked and crofted. This method was lengthy and tedious, and it monopolized large tracts of land that could have been used for farming.

Late in the 18th century, scientists discovered a chemical that had the same effect as crofting, but yielded much quicker results. In 1774, Swedish chemist Karl Wilhelm Scheele discovered the chemical element chlorine, a highly irritating, green-yellowish gaseous halogen. In 1785, the French scientist Claude Berthollet found that chlorine was an excellent whitening agent in fabrics. Some mill operators attempted to expose their fabrics to chlorine gas, but the process was so cumbersome and the fumes so strong that these attempts were soon abandoned. 

Another site goes into more detail about how the Dutch cornered the whitening market:

The whitening process with this lye method is a bit tricky. Additionally, it is cumbersome because it consumes several hours. Furthermore, it warrants extra care as it is pretty strong.

The Dutch are attributed for the modification they brought about in this sphere in the 11th and 12th century AD. During this time, they emerged as experts on the science of laundering in the entire European community. To soften the harsh effects, they seasoned lye with sour milk. They never let anybody know about their secret and, as a result, the process remained a mystery for many years.

Till the mid-18th century, the Dutch dominated and maintained their supremacy in the bleaching trade. Thus, all brown linen, manufactured at the time principally in Scotland, was shipped to Holland for the purpose of bleaching.

The entire course of action, from its despatch to return was a long process - it took about seven to eight months. 

As for the modern form of liquid household bleach, it wasn't a thing til the start of the 20th century:

 It wasn't until 1913 that a company named "The Electro-Alkaline Co", started to make a sodium hypochlorite bleach by chlorinating a solution of caustic soda, also known as sodium hydroxide (Mulrooney, 2013).

And here's the history of that company (the Clorox company as it became):

Clorox was founded in 1913 as the Electro-Alkaline Company by five Oakland, California-area businessmen, only one of whom had any knowledge of chemistry. Their objective was to convert brine from ocean water into sodium hypochlorite bleach using an electrolytic process considered to be technologically advanced for its time. Each partner invested $100 in the new venture, and in August 1913 they purchased a plant site. The company's first product, Clorox liquid bleach, was packaged in five-gallon returnable containers and delivered by horse-drawn wagon to local breweries, dairies, and laundries for cleaning and disinfecting their facilities. Labels for the new product identified it as being "made by electricity."

An initial stock issue of 750 shares at $100 each provided $75,000 in start-up capital. The company struggled through its early years and often depended upon personal loans from its directors to pay expenses. 

In 1916 a less concentrated liquid bleach product--5 percent sodium hypochlorite instead of 21 percent--for household use was developed and sold in amber glass pint bottles. William C. R. Murray, the company's general manager, came up with the idea of producing and promoting household bleach. Murray's wife, Annie, gave away samples of the formula to customers of the family's Oakland-based grocery store. Its value as a laundry aid, stain remover, deodorant, and disinfectant was also promoted by door-to-door salespeople who demonstrated how a solution of Clorox bleach and water could whiten an ink-stained piece of fabric. Orders were collected on the spot and then given to local grocers who purchased the necessary inventory from the company to fulfill them. Small and local at the time, Clorox was not affected by World War I. 

That 21% sodium hypochlorite formulation must have been pretty powerful stuff, given how quickly your ordinary 4 to 5% solution can white spot your clothes if it gets on them undiluted.  I can imagine  a 21% formula dissolving a hole in your pants immediately.  (Not to mention what it might have done to your skin.)

Anyway, now I know more.