| In the 16th century, India's textile workers discovered | | | | repeated submerging followed by oxygenation after |
| how to make color dyes adhere to cotton and linen, | | | | each dipping. If an area were to remain white, a resist |
| thus making it colorfast. Before this important | | | | paste made of wax or a flour paste was brushed on |
| discovery, colors and designs printed onto cotton and | | | | to cover it to prevent the dye from penetrating the |
| linen, would soon wash out and fade in the sun. Berry | | | | fabric under it. |
| and vegetable dyes were not fast. Clothes were drab | | | | There were two other methods that printers used to |
| and colorless. People valued wools and silks, which | | | | apply indigo to cotton: pencilling (also spelled penciling), |
| held color well. Silk was too expensive for the average | | | | and China blue. Pencilling was used to hand brush blue |
| person and wool was too hot in some climates. | | | | onto small areas of a multicolored print, usually chintz. |
| Most vegetable and plant dyes washed out except | | | | A brush applied the reduced dye directly onto the |
| for indigo, a blue dye, which is why many woven white | | | | area, where sit oxygenated quickly. It could look spotty |
| and blue check fabrics were woven in the colonies. | | | | as uneven, and have a poor registration. There were |
| Both indigo plants and cotton plants grew abundantly in | | | | more pencillers (usually young girls and boys) employed |
| the warm humid climate of India, as did the best plant | | | | in mid- eighteenth century print works than any other |
| for red dye obtained from the root of the madder | | | | job skill. |
| plant. Indigo was fast, madder red was not. But getting | | | | The China blue technique did not reduce the indigo |
| the blue dye from the indigo plant was not easy or | | | | plant beforehand. Instead, indigo plant was applied to |
| quick. It was labor intensive and produced an | | | | cloth using wood blocks or engraved copperplates. |
| expensive dye that was valued across the world. | | | | After printing, the cloth was placed first in a lime bath, |
| The primary method for dyeing with indigo was vat | | | | then in copper bath, then back and forth repeatedly. |
| dyeing, where a chemical reducing bath took place in a | | | | This yielded a light or light-medium shade of blue on a |
| vat (container) above or below the ground. This was | | | | light ground. Bird, bouquets and pillar prints made with |
| necessary in order to make the insoluble indigo plant | | | | fine liens are the result of this rare technique. |
| soluble. The process of getting the dark blue dye from | | | | Eventually, stable direct printing of indigo was possible |
| an indigo plant started with fermentation in the vat filled | | | | in the last quarter of the 19th century. Glucose utilized |
| with an alkali solution. The resulting dye liquor would be | | | | indigo in such a way that the reduced version |
| left to cool and harden. It was cut into hand-size | | | | combined with steam fixed the color. German |
| chunks to be shipped in divided boxes to indigo dyers | | | | scientists first synthesized indigo in the 1880s, patenting |
| who then ground it to a powder that was soluble in | | | | it in the early 1900s. Commercial dyeing with synthetic |
| water. Dyers boiled the mixture, then cooled and | | | | indigo did not begin until 1897, but home dyeing and trial |
| stirred it. They removed extraneous materials like | | | | runs were made earlier and synthetic dyes were |
| twigs that would affect the printing. Next, the mixture | | | | available to the public. Many shades of indigo dyed |
| was put into the vat with the cloth; copperas and lime | | | | cotton are found in quilts made from 1890 to 1918, the |
| were added to it and the dyebath became yellow in | | | | start of WWI. Synthetic indigo dye essentially replaced |
| color. After a time, the cloth also turned yellow. It was | | | | the use of natural indigo by the early 1920s. |
| not until it they lifted it from the vat that oxygenation | | | | Dyes on fabrics are one of the clues to dating textiles |
| took effect (in about 12-15 minutes) which turned the | | | | and quilts, but indigo dyes were used around the globe |
| cloth blue. Afterward the indigo was insoluble again. | | | | and for generations, making it quite difficult to date |
| Commonly, the last remaining color in an old faded or | | | | indigo dyed fabrics found in America. It is easier to |
| deteriorated quilt is cotton indigo dyed. | | | | date this fabric when it is on a quilt as the style of the |
| Simply adding more dye to the bath would not | | | | quilt provides a strong clue to dating it. |
| produce a darker shade of blue. This required | | | | |