Lac is the name given to the resinous secretion of the tiny lac insect (Laccifer lacca) which is parasitic on certain trees in Asia, particularly India and Thailand. This insect secretion is cultivated and refined because of the commercial value of the finished product known as shellac. The term shellac is derived from shell-lac (the word for the refined lac in flake form), but has come to refer to all refined lac whether in dry or suspended in an alcohol-based solvent.
Shellac is primarily used as a wood sealer and finisher today. It has the great advantage of being soluble in ethyl or denatured alcohol, an environmentally-safe solvent. Alcohol solvents also render shellac a quick dry—shellac coatings on wood generally dry in about 45 minutes, as opposed to oil finishes which take many hours to dry. In addition, shellac does not fade in sunlight or oxidize over time. However, shellac has a limited shelf life and may not dry properly if it has exceeded the shelf life recommended by the manufacturer. This shelf life may be as short as six months or as long as three years depending on the manufacturer's additives.
Industrial uses for shellac include floor polishes, inks, grinding wheels, electrical insulations, and leather dressings. This natural, resinous sealer is non-toxic and is Federal Drug Administration (FDA) approved for use to coat candies, pharmaceuticals, fruit, and baby and children's furniture.
Shellac is available at most hardware or paint stores in clear or white shellac or orange shellac, which imparts an orange-red tint to natural wood. Other tints derive their color not from dyes or bleaches, but because of the tree to which the lac bug has attached itself—the sap affects the color of the bug secretions thus altering the color of the refined shellac. Shellac may be applied to wood, over varnish, paint, glass, ceramics, even plastic with remarkable adherence, but it cannot be used under synthetic sealers such as polyurethane.
Lac has been cultivated for three centuries. For most of that time, the lac bug secretions were valued for the purple-red dye derived from being soaked in water. This dye was used to color silk, leather, and cosmetics and was cultivated primarily for this purpose until the 1870s. Then aniline or chemical dyes began to supplant these and other natural dyes.
As early as the sixteenth century, references were made to the usefulness of the lac bug secretions as a decorative lacquer for furniture and fine musical instruments. Natives of the Far East had laboriously cultivated and processed the shellac by hand, scraping the branches encrusted with the lac bug secretions, forcing the secretions into muslin, and holding long muslin bags of the secretions over the fire to liquefy and purify it. They pulled it by hand into huge sheets and then broke the sheets into flakes for re-moisturizing later.
Hand processes were partially replaced by the mid-nineteenth century. Just as the lacderived dye was about to fade in popularity, industrial plants began processing the lac secretions for use as a wood sealer and finish. In 1849, William Zinsser founded Wm. Zinsser & Company in New York. Zinsser's shellacs were soluble in ethyl alcohol and were the first quick-drying, tough, colorless finishes available in the United States. Shellac was particularly popular late in the nineteenth century and in the early twentieth century when houses were being quickly built in early subdivisions at break-neck speed—shellac was an ideal wood finisher because it was so fast to dry and several coats could be applied in a single day. A shellac known as buttonlac, a very dark shellac, imparted a very deep walnut color to inexpensive woodwork that people then found very desirable.
Shellac is generally made from two ingredients, raw seed lac and ethyl alcohol. In fact, most companies want to purify shellac as completely as possible—impurities from the bug, the cocoon etc. are removed, as are natural waxes. Shellac is generally shipped in dry or flaked form and is re-moisturized with an alcohol solvent, generally denatured alcohol. Some companies add ingredients to lengthen the shelf life of their product but will not reveal these proprietary additives. Shellac that is bleached (or made into clear shellac) are dissolved in sodium carbonate and centrifuge to remove insolubles and then bleached with sodium hypochlorite.
The role of the lac bug
- 1 Shellac is produced by a tiny red insect. Swarms of the insects feed on certain
trees, primarily in India and Thailand, known informally as lac trees. The lac bugs' life cycle is only six months, in which time they eat, propagate, and secrete the resin they've taken in from the tree to produce shellac.
In certain seasons of the year, these insects swarm in huge numbers on the trees, settle on branches, and project protrusions into the tree to penetrate the bark. They suck up the sap and absorb it until they feed themselves to death (called the feast of death amongst the indigenous peoples). At this same time, propagation continues, with each female lac bug laying about 1,000 eggs before dying.
The sap is chemically altered in the lac bug's body and is then exuded onto the tree branch. On contact with the air, the excretion forms a hard shell-like covering over the entire swarm. This covering forms a crust over the twig and insects. As the female lac bug is exuding the ingested sap she is preparing to die and is providing a fluid in which her eggs will mature under protection. The males' role is to fertilize the female, and it is after fertilization that the females' lac output is vastly increased. The adult males and females become inactive, and the young start to break through the crust and swarm out.
Refining the crusty resin
- 2 Workers cut millions of encrusted branches, called sticklac, for transportation to refineries of some sort (either handrefined or mechanically refined). Some workers use mallets and break off the crusty coating much as ice is broken from branches in the winter (it is referred to as grainlac).
- 3 At refining centers, sticklac is scraped to remove the secretions from the twigs. Sticklac and grainlac is ground with rotating millstones. The resulting ground material is quite impure, containing resin, insect remains, twigs, leaves, etc. The mixture is forced through a screen, removing the largest of the impurities.
- 4 The sifted resin mixture is put into large jars and stomped by a worker to crush granules and force the red dye from the lac seeds and the insect remains will be freed from the resin. Dye water, scum, and other impurities are then washed away in several rinsings. The mixture is spread out on a concrete floor to dry and called seedlac because it resembles seed. Seedlac is the raw material from which both orange shellac and bleached or clear shellac are produced.
Shellac may be made from seedlac by hand or by modern mechanical equipment. Nearly all American-used shellac is refined with the help of machinery, using a heat-or solvent-based process.
- 5 Seedlac is melted onto steam-heated grids. The molten lac is forced by hydraulic pressure through a sieve or screen, either of cloth or fine mesh. The filtered shellac is collected and transferred to a steam-heated kettle, which then drops the molten liquid onto rollers. The liquid is squeezed through the rollers and forced into large, thin sheets of shellac. When dry, this shellac sheet is broken into flakes and transported to another area in which the flakes are combined with denatured alcohol to produce the consumer's shellac.
- 6 In this process, the seedlac and solvent, usually ethyl alcohol, are mixed in a dissolving tank, refluxed for about an hour and then filtered to remove impurities. The filtered resin is sent through evaporators that remove the alcohol solvent, rendering it a viscous liquid. This liquid is then dropped onto rollers, which force it into sheets. The sheets are then are dried and flaked apart.
Despite the removal of much of the red dye from the lac seeds in the refining process, shellac remains an orangish solution after processing is complete. Some consumers prefer a clear shellac finish, so manufacturers have developed a way to bleach the color from the shellac.
- 7 Bleaching begins with dissolving seedlac, which is alkali-soluble, in an aqueous solution of sodium carbonate. The solution is then passed through a fine screen to remove insoluble lac, dirt, twigs, etc. The resin is then bleached with a dilute solution of sodium hypochlorite to the desired color. The shellac is then precipitated from the solution by the addition of dilute sulfuric acid, filtered, and washed with water. It is dried in vacuum driers and ground into a white powder ready for shipment to a plant that will add liquid to the flakes.
Mixing shellac for the consumer
- 8 Large shellac manufacturers are shipped the dry shellac flakes. They then remoisturize the flakes by adding denatured ethyl alcohol. Shellac is offered to the consumer in flake form or suspended in denatured alcohol. It is the latter than is most popular with the consumer. Manufacturers of shellac refer to the concentration of shellac flakes to denatured alcohol in terms of pounds of cuts—the number of pounds of
shellac flakes dissolved into a single gallon of denatured alcohol. Thus, a one pound cut of shellac contains one pound of shellac flakes dissolved in a gallon of alcohol—very dilute shellac. The manufacturers' standard cut offered to the consumer pre-mixed is termed a three pound cut. Some consumers then dilute it further with denatured alcohol if they so desire.
The most popular shade of shellac sold premixed is the orange shellac although clear or white shellac is also offered pre-mixed to the consumer. Manufacturers always stamp the date of mixing of the shellac into the can. Each manufacturer has a recommended shelf life for the product and the consumer should heed that the product is not used after the period suggested by the manufacturer. If used after the time span recommended, the shellac may never dry completely.
For woodworkers who prefer the deep rich colors of garnet shellac or buttonlac, the dried flakes of these shellacs may be purchased from the manufacturer and mixed with denatured alcohol by the consumer.
The denatured ethyl alcohol used in the process of manufacturing shellac is a strictly regulated byproduct and is known as a volatile organic substance (VOC). The most dangerous or hazardous part, perhaps the most polluting, are the insolubles that are refined out of the sticklac and grainlac such as twigs, cocoons, leaves, bug bodies, etc. saturated with alcohol. The shellac industry is working on building huge evaporators, which will suck all the alcohol out of these insolubles so the volatility will not be an issue. Shellac flakes are all natural and non-toxic. It is the alcohol solvents that are regulated.
Chemical analysis does not assist in determining the quality of shellac. More important are empirical tests such as flow and shelf life that most customers have articulated as of great concern. In addition, carefully examining the purity of the shellac by removing as many of the natural impurities found within the sticklac is of utmost importance (insolubles are defined by the undissolved matter remaining when the resinous compound is mixed with hot alcohol). All refining processes are monitored for their effectiveness in removing these undesirables.
Where to Learn More
Russel, M. Shellac. London: Ann Eccles and Son Ltd for Angelo Shellac, 1965.
The Story of Shellac. Somerset, NJ: Wm. Zinsser & Co., 1989.
—Nancy EV Bryk
Having never compromised their ethic of free expression in favor of album sales or popularity, Shellac became perhaps the quintessential independent rock band over the course of a decade. They repeatedly managed to deliver some of rock's most brutally honest recordings while garnering respect as purveyors of the genre in its purest form. In addition, they have been interested in rock music's behind-the-scenes politics and in high-fidelity production electronics.
Consisting of guitarist, vocalist, and engineer Steve Albini, bassist Bob Weston, and drummer Todd Trainer, Shellac took shape in Evanston, Illinois, in 1992. Albini's noisy and confrontational Big Black and Rape-man projects had disbanded after causing controversy in the hardcore music scene over the previous ten years, and he was ready for something new. When Albini invited Weston, a former bassist in the bands Sorry and Volcano Suns, to work for him at his Electrical Audio studio in Chicago, the trio started playing regularly, releasing a few singles on the local Touch & Go and Drag City labels.
Holding down day jobs, the group members never allowed their music to become their main source of income. As a result, they never felt the pressures experienced by many other bands that have been locked into bad record contracts and other obligations. Shellac's dealings with independent labels generally benefited both band and label equally, with neither party pressuring the other to try to make a recording that exceeded its inherent limitations.
Albini had been a much sought-after producer for some years and had direct experience with the problems that many bands faced when dealing with major labels. He grew more disillusioned with the state of commercial music with each record he produced, and finally he vented his observations in the now-famous essay "The Problem With Music," which appeared in the Chicago literary journal The Baffler. The essay outlined in the simplest terms how naive bands with the best intentions upon getting signed could have a hit recording and still end up penniless and disenchanted. The piece was especially relevant in the early 1990s, when major labels were mining the talents of the country's numerous underground music scenes and exploiting many of Albini's friends' bands in search of corporate profits.
Albini had studied journalism at Northwestern University and had always held a critical attitude toward corporate America. It was his general intention to inform the public about music industry ethics and practices while at the same time representing his own interests and opinions truthfully. Albini earned a reputation in the industry as an opinionated and hard-nosed producer, leading many major labels to steer clear of him for fear that his honesty would compromise the label's control over the artist whose career they might be trying to develop. The fact that recording industry executives were reluctant to use him, however, was exactly what led many bands to insist that Albini produce their albums. Musicians felt that Albini would stick up for their best interests and that at the same time they could count on his studio expertise to create sonically superb recordings.
During Shellac's career Albini produced hundreds of records, a number of them now considered alternative rock classics. These included Nirvana's In Utero, the Pixies' Surfer Rosa, and the Breeders' Pod. When producing smaller bands on independent labels, he charged what each band could afford and worked for a flat rate, declining to accept royalties. As well, he shunned the credit of producer, opting instead for engineer since he believed that no one should be more prominently credited on a recording than the band itself.
While Albini and Weston produced records for numerous bands, and Trainer held down a management job, Shellac released its first LP in 1994. At Action Park appeared that fall, and, by word of mouth alone, became a hit in underground circles. Featuring what would become Shellac's trademark sound—angular guitars, direct, punchy vocals, and crisp rhythm—At Action Park took listeners on a trip through the dark depths of human nature and revealed much about Albini's misanthropic outlook on life. His obsessions with violence, sex, and anger were as evident here as they had been on his recordings with Rapeman or Big Black, but so was his dedication to high-fidelity sound reproduction.
Albini's devotion to the truest recorded analog sound led the band to release the recording on vinyl several weeks before it came out on cassette or CD. They hoped to induce fans to purchase the album in the LP format, one that Albini considered superior. As well, the band and its label, Touch & Go, decided not to promote the record to the press or to college radio stations, assuming that those who might enjoy the album would eventually seek it out themselves or discover it through word of mouth.
In line with Albini's do-it-yourself philosophy, most of Shellac's interviews were granted to independent music fan magazines and alternative newspapers where noncommercial values were prized and major-label promotional politics were absent. Shellac's tour schedules saw the group visiting only cities that all the members wanted to visit. Tours were never money-making ventures but rather vacations on which the band played rock shows, at locations as obscure as 4-H clubs. One show in Evershot, England was organized by rocker PJ Harvey's mother. The band's early tour of Japan yielded the 1994 record Live in Tokyo, issued in limited release by Japanese noise artist and friend of the band members K.K. Null.
Shellac's next release, the 1997 instrumental recording The Futurist, was also extremely limited in its production run—a mere 799 copies were distributed, exclusively to family and friends—and Shellac's growing fan base clamored for something that they could actually get their hands on. Still, nearly four years went by before Shellac followed up the successful At Action Park with another full-length recording.
The release of Terraform was substantially delayed because of copyright clearance issues related to the album's cover art. After the wait was over, though, the recording—produced at the Beatles' famed Abbey Road Studios—still garnered its share of decent reviews. Rolling Stone 's Ivan Kreilkamp commented that "Shellac continue to make exceedingly precise music in which silence counts as much as noise, and the rhythms … are wound as tight as industrial-strength springs."
The trio spent much of 1998 and 1999 recording their 2000 release 1000 Hurts, whose title was a pun on the unit of measurement of frequency denoted by the abbreviation "Hz." Included on 1000 Hurts was one of Albini's signature odes to violent attack, entitled "Prayer to God"; in the lyrics he asks outright to have a woman and her partner mercilessly killed. The vinyl issue of 1000 Hurts included a free CD copy of the disc for the listener's convenience.
For the Record . . .
Members include Steve Albini , guitars, vocals; Todd Trainer , drums; Robert Weston , bass.
Group formed in Evanston, IL, 1992; released debut album At Action Park, 1994; released live album Live in Tokyo, 1994; released The Futurist, 1997; released Terraform, 1998; released 1000 Hurts, 2000.
Addresses: Record company— Touch & Go, P.O. Box 25520, Chicago, IL 60625, phone: (773) 388-8888, fax: (773) 388-8888, website: http://www.tgrec.com
Notwithstanding its nasty tone, 1000 Hurts was well received by the music press. Had that not occurred, though, Albini and the other band members likely wouldn't have minded much; the usual concepts of success never held much appeal for the members of Shellac "[Shellac] has not been the No. 1 obligation in any of our lives," Albini told the St. Paul Pioneer Press. "The band can exist in a quite comfortable way without us ever having to play another show or make another record."
At Action Park, Touch & Go, 1994.
Live in Tokyo, Nux, 1994.
The Futurist, Touch & Go, 1997.
Terraform, Touch & Go, 1998.
1000 Hurts, Touch & Go, 2000.
The Baffler, November 1993.
Rolling Stone, April 2, 1998; September 28 2000.
St. Paul Pioneer Press, September 12, 2002.
"Shellac," All Music Guide, http://www.allmusic.com (Nov-ember 28, 2003).
shel·lac / shəˈlak/ • n. lac resin melted into thin flakes, used for making varnish. ∎ a thin varnish containing this resin. • v. (-lacked / -ˈlakt/ , -lack·ing / -ˈlaking/ ) [tr.] 1. [often as adj.] (shellacked) varnish (something) with shellac. 2. (usu. be shellacked) inf. defeat or beat (someone) decisively: they were shellacked in the 1982 election.