Continuous Carpet Dyeing

Beginnings of Continuous Carpet Dyeing 22, 23

The following is the story as told by those people who participated in this history. I wish to extend my thanks to all who told their story to me. Gary N. Mock

The rise in new home construction in the 1950s and the introduction of synthetic fibers led to an explosion in the need for rapidly and economically converting fiber to carpet. Tufting rather than weaving carpet made it possible to quickly convert synthetic fibers to floor coverings. Traditional beck dyeing was a batch process and it was cumbersome to handle 12 foot wide soaking wet carpet. However, business was growing at a rate of 13% per year. 1 Could this process be automated along the lines used to dye flat fabric? In 1963, a delegation of German carpet executives led by Dr. Schäffler, and Herrs Schmitz, Kauffels, Fenneckels and Schröder came to Dalton, GA, the home of tufted carpet. 2 Peter Zimmer showed them his flat­bed screen carpet printing machine built for E.T. Barwick in LaFayette, GA and installed in 1962. 3, 4 The idea of continuous coloration hit home: a Zimmer Machine was delivered to VTW/Berlin in 1964 and trials were begun. During 1964 and 1965, the housing market expanded and batch dyeing could not keep up. The carpet manufacturers were ready for a solution.

In the United States, Kurt Zimmerli worked for BF Perkins and later Butterworth. 5 He read that Eduard Küsters had developed a new adjustable deflection padder. 6 After talking with Küsters, he tried to interest Perkins in US representation and Mr. Küsters wanted continuous processing for the US market. Perkins was not interested. Batson signed on to represent the Küsters development. The idea took off for flat fabric and soon Hans Grüber was sent to the US to give customer service. 18

 

Developing a Machine 

The first serious attempt to dye carpet continuously occurred at Bradford Dyer’s Association (BDA) in the early 1960s. 7 Stalwart tried as well and Roland Weber of Bayer AG saw their slop dyeing machine in 1965. 8 Several machines were built in cooperation with Pickering, a manufacturer of tufting machines. It was a simple machine but was unpredictable. Unlevel side­ center­side results kept this machine from real success.

BDA Slop Dyeing Schematic
Bayer Farben Revue May 1967

  1. Lead In ­ undyed carpet
  2. Dye Trough
  3. Steamer with roller supports
  4. Wash off unfixed dye

In 1966, Küsters began discussions with Fleissner, manufacturers of continuous finishing machines, Schaffer, a carpet manufacturer, and Dr. Würz of BASF, a supplier of dyes and chemicals. 2 Küsters would provide the padder while Fleissner would provide the steamer and washing range. 9 Very soon, Küsters was convinced they were on the wrong track for tufted carpet processing. He withdrew his support. BASF and Fleissner went ahead and announced their design in the September, 1966 Melliand Textilberichte. 10 A drawing depicted two two­roll padders, a suction drum steamer and suction drum washers. Weber discussed the Stalwart­Pickering machine with Küsters and agreed that Küsters’ idea was sound but the padder was very expensive. Küsters decided to move forward.

Meanwhile, Gerber, also located in Krefeld, developed two versions using a kiss­roll pick­up. Küsters said, “Sirs, let’s get the ball rolling, let Küsters face the challenge.” 2 His specifications were:

Five meter working width
Dye applicator with a padder with two S­-rolls
A loop steamer with a capacity of 60 meters
Three wash units.

Completion of the new range was targeted for mid­March, 1967. TAG, a carpet manufacturer nearby in Krefeld, was a ready partner for field erection and testing. The German manufacturers were great believers in working with others “within sight of the smokestack”, meaning, “nearby.” Interest was peaking in Germany. Melliand carried an article in the April 1967 issue by Dr. Rüttiger of BASF where the BDA machine was mentioned, while the Fleissner, Gerber and Küsters machines were discussed at length.11

 

The Selection of Dyes for Continuous Nylon Carpet Dyeing

The selection of dyes for the proposed continuous dyeing of nylon was rather straight forward since there was experience from batch dyeing. By 1964, DuPont began a research program to develop a combination of level­ dyeing acid dyes for their staple and bulked continuous filament (BCF) fibers. 19 A problem reared its ugly head when fume­fading of blue dyes (from gas heating combustion by­products) became known. Nevertheless, dyes for batch processing might not be the same for continuous. Dye trials took place at Lees Carpet, Rabun Gap, GA and elsewhere.

 

First Trials

By the middle of March, 1967, the Küsters range was installed at TAG and trials began. Numerous problems developed:

Tailing, caused by differing dye affinities in a normal three dye combination
Air entrapment in differing pile heights, especially in so­called high/low constructions
Loose fiber build­up on the padder roll surface and in the dye liquor recirculation system
Heavy pollution of the dye liquor due to color bleeding from the jute backing (tufted carpets were made using a jute plain weave with nylon fiber pile).

Those first samples shown to the carpet and dyestuff people did not begin to meet commercial requirements. The color yield, appearance and depth of shade did not equal beck­dyed carpet. Furthermore, the carpet looked flat and gray. The S-­roll did not allow enough dye pick­up. They tried a nip­dye padder to allow increased dye pick­up but still the carpet had a gray cast and the tips of the vertical tufts were not dyed to shade (the term used was “frosty”). Thickening agents were tried and increased from 2 to 5 g/L and still the effect was unsuitable.

The team went back to the laboratory. It was apparent that the amount of dye has to be increased well beyond that possible using the S-­roll. A successful dyeing required a wet pick­up as high as 600 – ­800 per cent to overcome the frosty tips and give penetration to the base of the pile. What kind of applicator could give such conditions at desired speeds of three to seven meters per minute? Eduard Küsters appointed his design engineers, Valentin Appenzeller, father of the S-­roll, and Hans Kutz, to make an all­out effort. 2

 

The Dye Applicator

One night after many hours of brain­-storming, Appenzeller and Kutz decided to try a trough half-­filled with thickened dye liquor with a roller turning in the liquor which would pick up the liquor. This is a traditional kiss-roll applicator. A doctor blade would be used to remove the dye liquor from the face of the roll and transfer the dye to the carpet face. The idea worked! For exact dosing, the speed of the transfer was controlled according to pile density and range speed. As trials moved back to TAG, it became evident that high liquor volumes could not be held uniformly on the carpet. Dye flowed over the selvage onto the steamer floor and the resulting selvages were lighter than the center. Loose trash fiber continued to be a problem. In order to remove dirt and loose fiber, the S-­roll padder was moved in front of the dye applicator. The S­-roll padder served as a pre-­wash and pre­-wetter and left a residual wet pick up of about 80 per cent. Now the dye applicator could work with a lower wet pick up (250 – ­300 per cent) and resulting in less wastage. The secret to success: wetting to displace air, squeezing to remove the air and water, and flooding with color in the dye applicator.

Schematic of Kuesters Range
Concept on US Patent 3,541,815

In April, after further modifications and completion of the production –scale range at TAG, Dyeing trials began anew. The dye applicator was stacked above the two­roll padder (see US Patent 3,541,815 filed June 30, 1967), with liquor trough capacity of approximately 80 Liters, and a continuously adjustable rotating dye roller. 12 When the roller speed increased, the volume of dye applied changed in proportion. When the doctor blade was raised, dye application ceased. This allowed lead­in and tail­out of runs without wastage of dye.

 

Debugging

The first recipes were formulated by TAG. Roland Weber remembers spending half the year running nearly daily trials. 7 Bayer AG was interested in selling dye as well as in the development of a successful dyeing of their Dralon polyacrylic fiber. In the end, they were not successful in making an entry with the thermoplastic fiber in competition with nylon. Nylon was vastly superior as a floor covering. Other dye companies also ran trials at TAG. A typical day might see trials by the big four dye suppliers coming in four hour shifts: Geigy, Sandoz, Ciba and Bayer, all used the TAG facility. Interestingly, foam, normally a nemesis in dyeing, was encouraged as a vehicle for ensuring the carpet tufts were dyed to the tips. A window in the steamer allows visual confirmation of the foam height. By the spring of 1967, Kurt Zimmerli as a representative of Butterworth and Küsters in the US regularly had discussions with Küsters. Potential customers in the US, including Barwick, were kept appraised of developments.

Woven selvages were a problem. The tightly woven selvage was much stronger than the center. Carpet heavy with dye tended to sag and drag through the steamer. Supporting rolls were added at the bottom of each loop within the steamer.

By June 1967, the project was well on the way to assuring commercial use. European style low­pile carpet was successfully dyed. Barwick arranged to send a sample of heavier samples with a weight up to 2000 g/m2, twice the weight of European carpet. Thus began a difficult trial period. Frosting and low penetration sent everyone “back to the drawing board”. Everyone realized the enormous potential and importance of the US market.

Both Jim Stephenson of Barwick and Bob Turner of DuPont examined samples run in Krefeld and discussed these problems with the fiber suppliers. DuPont was the leading carpet fiber supplier followed by Monsanto and Allied, not necessarily in that order. The range was further modified to allow for higher liquor volume, improvement in the wash range and additional spreading to allow width control.

In July, new samples arrived from Barwick. Trials were successful enough to push on. In August, larger samples arrived. Jim Stephenson came to Krefeld again and was convinced that heavier styles could be dyed. Here was the breakthrough – the ability to dye these heavier samples. As the summer holidays in Germany ended, the development team attacked the project with renewed vigor. A new carpet backing called Polyback was tried. Made from slit strips of polypropylene, the backing would offer no bleeding problems. However, the looser construction compared to tightly woven jute did prove to be difficult to manage. The team worked to solve the problem.

Ad flyer for the 1967 ITMA show in Basel

Late that summer, Eduard Küsters decide they were ready for a full commercial push at the upcoming ITMA show in October in Basel. A special leaflet was prepared and distributed to carpet industry executives who were certain to be in Basel to view the latest offerings of new machinery for their businesses. Normally this show was not geared for carpet but the promise of a dyeing machine that operated at 10 m/min was hard to ignore. 2, 20

 

ITMA ’67 Basel

There was a lot of excitement as the show neared. Kurt Zimmerli and Eric Norman of Butterworth and Manfred Enger of Küsters invited major US customers to come to the show, and at the end of the show, fly via charter flight to Krefeld to see a demonstration on the full­width pilot machine. ITMA was the place to be in those days. People travelled from around the world to see the latest developments. Every room in Basel and nearby was taken. People took trains and commuted from Zurich and Lucerne every day. Kusters unveiled their Continuous Carpet Dyeing Range. Drawings and dyed samples were available. 13

Early in the morning following the close of the show, the Who’s Who of the US carpet industry boarded a chartered DC­6 and flew to Düsseldorf. Eric Schlaginhaufen of Geigy remembered attending a party at the Geigy canteen during the show. Getting up at 6:00 AM to catch a plane took dedication. Someone was overheard to say, “If this thing goes down, there goes the top management of the US carpet industry. The plane safely touched down and all were bused to TAG in Krefeld. The group of about 70 gathered around the installation attended by seven technicians. The trial ran in two different colors at four meters width and eight m/min. As the trial progressed, the men ran around the machine, and constantly checked for crocking using their white handkerchiefs. To their absolute amazement, the dyeing was the equal of any seen on a beck. Not wishing to push their luck with further trails, the group was taken to the Korf Restaurant in Krefeld and served huge steins of local beer and a traditional German autumn lunch. All invitees were flown back to Basel with the exception of the Barwick delegation and representatives from Küsters. Zimmerli, Norman and Enger met immediately with Stephenson, Lyle Jones and Roger McNamara of Barwick. 5 The talks went into the night and ended shortly before 2 AM. The Barwick people asked to adjourn for a half hour in their hotel and called Gene Barwick the CEO back in the states. They soon returned at 2:15 with permission to order the range. The first Küsters carpet range sold anywhere had been booked.

Weber remembers walking through the Kusters booth the next morning and being called in to see Mr. Kusters, who had just received a Telex from Mr. E.T. Barwick, confirming the first order. 7 He remarked, “This is the start.” Manfred Enger was so pleased with the trial that he wanted to give a sample to everyone who had attended. Upon checking with the people at Dura, Germany’s largest carpet company, who supplied the carpet for the trial, they were rebuffed, “…not one square could be cut for samples.” Many felt Dura wanted to protect a trade secret in the construction of their carpet. In fact it was no different than any other, just a lighter construction than US standards. Shortly after the order from Barwick, World Carpet ordered and Küsters had the second order. 14 World was actually the first to have a machine in production. Mr. Shaheen Shaheen remembered a building without walls and asking his electrical crew to work through the night in order to start the machine ASAP. 14 Ray Bertani and Ron Hardee recalled running an early trial on two­tone nylon carpet using disperse and acid dyes. This resulted in a deep red shade and was dyed at the Green Street plant early in 1968. Barwick, owner of the flat beds Peter Zimmer machine installed in 1962, continued to innovate and installed another first, the first rotary screen printing machine (again, developed by Peter Zimmer) in 1968 in the Dalton, GA plant. 3 Then, in rapid sequence, orders came in from the other major US companies: Foremost, Armstrong­Cork, Stevens, and others.

At this time, in complete secrecy, there were two BDA machines installed in Germany, one at VTW, Berlin and the other at Globus, Einberg. The first Küsters machine in Germany, after TAG, Krefeld was sold to DLW, Bietigheim.

In December, following the October ITMA show, DuPont sent Phil Ebert to TAG to run trials with their BCF (bulked continuous filament) carpet. The trials ran successfully with level dyeing side­center­side and uniformity from end to end. 19 Many other companies were interested in these developments. Melliand began a series of review articles. The March 1968 issue featured, in order, the Küsters machine with overflow applicator; the Fleissner with a padder; and the Gerber with a DDP­Unicolor kiss­roll applicator. 15

Continued on Page 2

 

References

  1. Carpet and Rug Institute, 1995 Industry Review, Dalton, GA, 1996.
  2. Kutz, J., Küsters, Personal communication, March 1997.
  3. Zimmer, P., Zimmer Print Machine, Personal communication, April 1997.
  4. Weiss, F., Melliand Textilberichte, 45, 1, January 1964, p60.
  5. Zimmerli, K., Zima Corp., Personal communication, September 1996.
  6. Küsters, E., Melliand Textilberichte, 39, No. 1, January 1958, p88.
  7. Weber, R., Bayer/DyStar, Personal communication, January 1997.
  8. Weber, R., and H.­J. Huypen, Bayer Farben Revue, 13, May 1967, p36, 14, February 1968, p41.
  9. Heise, W., Bayer/DyStar, Personal communication, December 1996.
  10. Anon., Melliand Textilberichte, 47, No. 9, September 1966, p1020.
  11. Rüttiger, W., Melliand Textilberichte, 48, No. 4, April 1967, p423.
  12. Küsters, US Patent 3,541815, filed June 30, 1967.
  13. Schlaginhaufen, E., Carpet and Rug Industry, March 1988; Personal communication, December 1996.
  14. Shaheen, S., World Carpet, Personal communication, January 1997.
  15. Anon., Melliand Textilberichte, 49, No.3, March 1968, p339.
  16. Keller, A., Continuous Dyeing of Carpet – A Continuous Challenge, Küsters Memo, November, 1985.
  17. Kohnen, J., History of Küsters Carpet Applicators, Kusters Memo, November, 1996.
  18. Grüber, H., and J. Kutz, Küsters, Personal communication, May 1997.
  19. Ebert, P., Personal communication, May 1997.
  20. Küsters ITMA’67 leaflet.
  21. Küsters Customer Reference List. May 1997.
  22. Mock, Gary N., Development of Continuous Carpet Dyeing, AATCC Book of Papers 1997, p123­132.
  23. Mock, Gary N., Early Development of Continuous Carpet Dyeing, Textile Chemist and Colorist, 30(8), 66­ 71, 1998.