Introduction

For my project, I originally wanted to dye both wool and paper with the same dye and compare the results using the colorimeter. But as Dr. Bordley explained, it takes a different kind of dye to dye wool than it does for paper, so there would be no point in trying to compare materials that were dyed with different types of dye (too many variables!). Since I reallly wanted to work with paper, Dr. Bordley suggested that I dye pulp that had been beaten for different times and test dye absorption as a function of beating time. We all remember the first paper making lab where we recorded the drainage time of denim for different beating times; the beating time of pulp has an effect on the overall quality of the pulp, drainage time, quality of paper, etc., so I figured that testing dye absorption as a function of beating time would yield discernible results.

Background

As pulp is beaten, it begins to fray and break, creating branchings called fibrils and small, free pieces of fiber which are called fines. Fibrils and fines are the main reason that drainage time increases as the beating time of pulp increases; the fines and fibrils absorb excess water. My hypothesis is that the longer the pulp is beaten, the more dye it will absorb because the fines and fibrils that result from prolonged beating increase the surface area of the fiber, allowing it to absorb more dye. Dyeing pulp is not the same as dyeing wool; with wool we used acid dyes, which the wool exhausted. Pulp requires cotton dyes, which do not exhaust, and therefore the time left in the dye bath is a factor rather than the percent of exhaustion of the dye bath. There are several factors in this experiment; I varied the beating time of the pulp. Other factors, controlled in this experiment, include:

• type of fiber
• beater setting
• temperature of dye bath/pulp while dyeing
• type of dye
• color of dye
• amount of dye
• amount of NaCl
• amount of dye activator
• whether or not pulp is removed before activator is placed in dye bath
• order of dye, NaCl, dye activator being placed in dye bath
• amount of time left on heat
• amount of pulp used
• amount of water used to rinse pulp
• whether or not pulp is rinsed
• amount of water used to dilute pulp in order to make wafers
• drying method

Procedure

Materials Needed:

• approximately 257 g dry abaca fiber
• beater
• 6 400 mL beakers
• 60 mL PRO MX reactive dye--red
• 120 mL dye activator
• 30 g NaCl
• hot plate
• thermometers
• Saran wrap
• filter paper
• funnels
• tin can (deckle)
• wire screen (mold)
• graduated cylinder
• felts, pelons, 2 L water bottle "rolling pin"
• drying board
• heat gun

Procedure:

1. Weigh close to 1/2 pound of dry abaca fiber (in this case, 257 g)

2. Beat for 60 minutes at a setting of 2, gathering 150 mL samples every 10 minutes (i.e., there are 10, 20, 30, 40, 50, and 60 minute samples)

3. Prepare the dye bath:

a. heat to above 52 degrees C (I kept at a steady temperature of 60 degrees C)

b. add 5 g NaCl

c. add 10 mL dye

d. add pulp and let the dye bath/pulp sit on heat for 10 minutes, stir frequently

e. Remove pulp from dye bath: pour into a funnel lined with filter paper so that the dye bath drains into a clean beaker

f. Add 20 mL dye activator to the dye bath

g. replace the pulp into the solution

h. Let stand on heat for 60 minutes; keep at a constant temperature of 60 degrees C

i. Remove from heat and let stand overnight; make sure to cover each beaker with Saran wrap!

4. Rinse the dye: set up a funnel lined with filter paper over a clean beaker, and run 300 mL of water through the pulp; repeat until water drains colorless

5. Dilute the pulp with water to 250 mL

6. Make a wafer of paper from the pulp:

a. Using a wire screen as a mold, a tin can as a deckle, a funnel and a graduated cylinder, pour the diluted pulp solution through the tin can. When it stops draining, remove the tin can and couch the wafer onto a moist pelon. Cover with another pelon and several felts. Roll gently with a "rolling pin" (a 2 L bottle of water) to remove excess water. Remove the felts and pelons, and gently transfer the wafer of pulp from the pelon to a drying board.

Lovely picture of me performing step 6

 

7. Dry the wet wafers with a heat gun.

8. Measure with colorimeter.

Observations and Data

Observations

Inital Samples

While dyeing

Pulp before rinsing

Pulp after rinsing

During Rinsing

Sample 4 during Rinse 1

Sample 4 during Rinse 2

Sample 4 during Rinse 4

Data

Colorimeter Readings

Conclusions

As the colorimeter values show, there is no discernible pattern in the readings. There are several explanations for this. There is the possibility that beating time has no effect on dye absorption. There are, however, several variables involved in this experiment, only one of which (the beating time of the pulp) I varied. Although I tried to keep the others controlled, there is the possibility that I accidentally allowed them to vary slightly from sample to sample. For example, the amount of dye or dye activator may have varied very slightly between the samples, as they were measured with the colorimeter, but these variances are so slight that it doesn't seem that they would make a difference.

Based on the results of the colorimeter readings, I would suggest that an impatient artist may dye paper with a shorter beating time with the same results as pulp with a longer beating time. The pulp with the longer beating time, however, creates a better quality paper.

References

http://www.prochemical.com/directions/MX_PaperPulp.htm

Acknowledgements

I would like to thank Dr. Bordley for giving me the idea for the project and providing information and supplies on dyeing pulp. I would also like to thank Nassrin el-Gosi for taking pictures!