6 December 2018
Life Cycle Analysis of Recreational Playing Cards- Materials
Playing cards have been a common medium for entertainment for millennia, originating in China as early as 618CE (History) and developing countless iterations and variations in materials and decorative elements ever since. These cards, usually used as nothing more than a game in both historical and contemporary contexts, are hypothesized to have symbolic or spiritual value. The correlation between the 13 cards per suit and 13 months of the lunar year, or the 52 cards and 52 weeks it takes for earth to complete an orbit around the sun are examples of such symbolism. However, regardless of what an individual uses the cards for, the material input of production is what remains relevant. Upon initial observation, the manufacturing process of playing cards appears relatively simple. This, however, is not quite the case. Through rigorous analysis of the process in which the raw materials, including paper, polymers and inks, are extracted and manufactured, the complexities regarding composition and the production cycle of an otherwise simple pack of playing cards will become evident.
As one may expect, one of the most critical elements of a card is the material used to create the physical backing that the patterns are printed onto. One such material is what most would think of a standard card: cellulose-based paper. Cellulose is a crucial element in the structure of plant cells (Cellulose), specifically in the cell wall that protects the eukaryotic unit from external threat. The processing of byproducts of forestry, including both hardwoods such as eucalyptus, aspen, and birch, as well as softwoods such as spruce, fir, pine, larch, or hemlock provide a valuable means of producing cellulose. An important detail to notice is that despite common belief, the production of paper is not limited to wood pulp. Wood pulp is still a great source of cellulose, but other flora such as cotton, sugarcane, flax, jute, and agricultural byproducts like corn stalks, sorghum bagasse, and straws of rye, wheat, or oats are also great sources of cellulose. Cotton in particular is one of the best sources due to a relatively high concentration of cellulose compared to other plants, and use of cotton in the production of playing cards is often associated with a high degree of quality. Many of these products are domestically produced, such as cotton, grown in 17 states (Frequently Asked Questions). Imports are also common, with wood being one such example; Canada, China, and Brazil (United States Wood Imports By Country and Region.) are the top 3 trading partners with the United States and the largest sources of imports. Once the cellulose-rich material is acquired, it is then pulped. This can be done in one of two ways (Types of Pulping Processes.). Mechanical pulping involves the grinding of wood against a water-lubricated stone, which results in the softening of the lignin, or the material that binds the fibers together, as a byproduct of the generated heat. Chemical pulp is acquired after chipped wood is cooked with chemicals such as caustic soda and sodium sulfate under large amounts of pressure, otherwise known as the Kraft Process. Caustic soda is also known as lye, and is imported from Asia, specifically India and China (Daoui, Amira). Sodium sulfate appears to be largely imported from China and Canada, though finding the condensed data regarding major importers and exporters is noticeably more difficult compared to other chemicals (Sodium Sulfate Import Data). Regardless of how the cellulose is pulped, it also undergoes the process of bleaching to become much more visually appealing to consumers. This is often done through the use of chlorine and chlorine-based compounds including sodium hypochlorite and chlorine dioxide (K, Steven S, and Rudra P Singh). Chlorine is exported by Canada and France (OEC - Brazil (BRA) Exports, Imports, and Trade Partners). Once the pulp is bleached, it is then processed to become paper, which is then glued together in layers to form a thick card base (madehow.com). However, cards are not exclusively created from cellulose.
Another common medium used in the production of card backs is plastic, specifically vinyl, otherwise known as polyvinyl chloride. Vinyl is a compound produced from chlorine and ethylene, each of which have complex processes required to harness the chemical as a usable material. While it was previously mentioned that chlorine was imported from France and Canada, it is important to note that it can be harnessed through electrolytic dissociation of salt, where NaCl is electrolyzed into chlorine and sodium (The Manufacturing of Vinyl). Ethylene is a byproduct of petroleum, and is harnessed through a process called “cracking,” where petroleum passes through high heat and pressure to produce ethylene, butadiene, propylene, and other byproducts. Once the chlorine and ethylene are acquired, they are united via the Monomer Process. This is done in one of two ways: direct chlorination involves combining pure chlorine and ethylene, while oxychlorination is undergone by reacting ethylene with the chlorine in hydrogen chloride. Once the ethylene and chlorine combine, they create a fluid called ethylene dichloride, which again undergoes the process of cracking to form vinyl chloride monomer, which is a gas at room temperature. Vinyl chloride monomer is polymerized into polyvinyl chloride through a variety of processes, including the suspension process, mass process, or emulsion process. The byproduct is vinyl resin, which is mixed with unspecified additives to produce a vinyl compound that can be used in card production. However, regardless of whether vinyl or cellulose is used in the production of the card backing, both still require some form of inked pattern to resemble a complete card product.
The ink itself its often what makes each card unique, as the patterns and variations imprinted onto the backing distinguish branding, intended use, and overall aesthetic. Unfortunately, the specific pigments used on playing cards is very difficult to find, and may vary from company to company. As such, the following process of producing the pigments is highly generalized, and may not necessarily be applicable in many cases. With the aforementioned clarifications addressed, inks are one of the more complex aspects of the card. The inks impart color through pigment in most cases (Ink Chemistry), and composition varies depending on color. In general, inks used in card production are oil-based (ACS Publications) printing inks. As such, linseed oil, soybean oil, or petroleum distillate are major components in the production of inks. Belgium-Luxembourg, Germany, and Turkey are the top exporters of linseed oil (OEC - Brazil (BRA) Exports, Imports, and Trade Partners), while Saudi Arabia, Russia, Iraq, Canada, and the UAE are major exporters of crude petroleum, which is processed into petroleum distillate to become usable in the production of inks. The oil base of the ink is combined with organic compounds, which are the salts of nitrogenous compounds (ACS Publications) to produce color. The pigment in ink can either be organic or inorganic; inorganic pigments are less frequently used and are based on metallic salts, while organic pigments are carbon-based (Pigments). Organic pigments are much more transparent due to much smaller particle sizes compared to inorganic pigments, which tend to be opaque and representative of larger particles. Both ink variations can be used in the production of playing cards.
With all of the major ingredients in the manufacturing of commercially accessible playing cards discussed, all that remains is assembly. The final process begins with a slab of card backing being fed into a large machine where rubber rollers transfer the inked image as the passes through (Playing Cards). The process of passing through rollers is repeated for as many times as necessary to get every different color onto the card. The assembly line is specially manufactured to allow the ink to dry on the paper before exposure to each new color. Once the inking process finishes, then the cards must be separated from each other. The sheet passes into a card-cutting section, where precise machines cut out identically-sized cards. These individual cards are stacked and passed to a “corner punching station,” where the corners are rounded off to give the cards their distinct shape. Finally, the cards are transported via conveyor belt to a packaging and processing machine, where they are inserted into paper boxes and sealed with a clear plastic. Any extra branding, such as stickers are added, and the final product is stacked on pallets to be shipped.
With the final product complete and in circulation, it is important to note that as a thorough life-cycle analysis, there are definitely shortcomings that may undermine the documentation of the processes that produce playing cards for the everyday consumer. First, because playing cards are not monopolized, many different companies produce their own cards, and every company may have differing methods and materials involved in assemble. Some may produce paper or plastic cards, but others may use more niche ingredients and processes. Another shortcoming lies in the incredibly vague process of dye production. Finding the exact specifications for what dyes are used for each company is nearly impossible, as the slightest variation in dye color could constitute an entirely different list of ingredients. Additionally, while the standard decks are often limited to black and red, the unlimited capability to include any color means that including every permutation of color would turn a simple analysis into an infinitely more complex thesis. Overall, the life-cycle analysis of playing cards is not an exact source of information, and is highly variable. As such, one may wish to pick and choose information that may be relevant, as taking the entirety of the paper as fact may not be entirely accurate depending on who produces the cards.
Overall, an analysis of how cards are made from cradle to grave proved to be dramatically illuminating in how complex the final product truly is. Many consumers put very little thought into the specific chemical compounds and necessary imports needed to produce material goods. As demonstrated, the whole process is highly convoluted and not what one may expect out of a deceptively simple product. Looking at the process as a whole is not only useful to expand one’s knowledge of material goods, but can also prove useful when applied to other general concepts. For instance, very few goods can be produced without environmental repercussions. By taking into account the processes that must be undergone to acquire each ingredient, informed consumers can begin to tie the costs of production with many ongoing environmental issues. Even if cards aren’t especially hazardous to the environment by themselves, the implications are still valuable to consider before going out and feeding into the cycle of consumption that is continuing to create serious implications for the future of ecological preservation.
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ACS Publications, pubs.acs.org/cen/whatstuff/stuff/7646scit2.html. Accessed 29 October 2018.
OEC - Brazil (BRA) Exports, Imports, and Trade Partners, atlas.media.mit.edu/en/. Accessed 26 October 2018.
“Cellulose.” NeuroImage, Academic Press, www.sciencedirect.com/topics/chemical-engineering/cellulose. Accessed 27 October 2018.
Daoui, Amira. “How to Import Caustic Soda?” Waystocap, WaystoCap, 13 Nov. 2018, www.waystocap.com/blog/how-to-import-caustic-soda/. Accessed 9 November 2018.
“Frequently Asked Questions.” Cotton: From Field to Fabric- Dyeing, Printing & Finishing, www.cotton.org/edu/faq/. Accessed 15 November 2018.
“History.” The Playing Card Factory, theplayingcardfactory.com/history. Accessed 4 November 2018.
K, Steven S, and Rudra P Singh. Advances in Ozone Bleaching, Part II; Bleaching Of Softwood Kraft Pulps With Oxygen and Ozone Combination". www.princeton.edu/~ota/disk1/1989/8931/893106.PDF. Accessed 9 November 2018.
“Pigments.” Pigments - Coloration & Surface Effects - Solutions & Technologies - BASF Dispersions & Pigments, www.dispersions-pigments.basf.com/portal/basf/ien/dt.jsp?setCursor=1_561069. Accessed 29 October 2018.
“Playing Cards.” How Products Are Made, www.madehow.com/Volume-4/Playing-Cards.html. Accessed 25 October 2018.
“Sodium Sulfate Import Data.” Fiberglass Importers List & Directory, Fiberglass Buyers & Prices in India, 28 Nov. 2018, www.infodriveindia.com/trade-data/advance-search.aspx?productdescription=sodium_sulfate&isimport=1&datatype=4&searchtype=1&queryid=3306243. Accessed 25 November 2018.
“The Manufacturing of Vinyl.” What Is Vinyl?, www.whatisvinyl.com/manufacturing.html. Accessed 28 October 2018.
“Types of Pulping Processes.” Types of Pulping Processes | CEPI - CONFEDERATION OF EUROPEAN PAPER INDUSTRIES, www.cepi.org/node/22334. Accessed 9 November 2018.
“United States Wood Imports By Country and Region.” World Integrated Trade Solution (WITS) | Data on Export, Import, Tariff, NTM, wits.worldbank.org/CountryProfile/en/Country/USA/Year/2015/TradeFlow/Import/Partner/all/Product/44-49_Wood/Show/Partner%20Name;MPRT-TRD-VL;MPRT-PRDCT-SHR;AHS-WGHTD-AVRG;MFN-WGHTD-AVRG;/Sort/MPRT-TRD-VL/Chart/top10. Accessed 28 November 2018.
Embodied Energy for Playing Cards
Playing cards have been a big part of leisure time in get-togethers and parties. They are made of paper or plastic, and consist of 52 cards divided into 4 suites. Playing cards have been an essential backbone tool in most casinos that drive big businesses. Casinos earn big, but so do playing card manufacturers. Certainly, there is a cost to produce playing cards at a huge scale, and a humongous energy requirement is therefore expected in its production- all the way from extraction of materials to transportation of the cards. Though it may seem that energy consumption in producing playing cards is minimal due to the very few materials used, the overall energy use from extraction and production of paper and ink to actual machinery is enormous.
For this paper, we limit to considering energy usage only to machines and processes that are on the top level. Energy consumption to make the certain machines itself will not be considered.
Despite the process of paper making advancing through the years and becoming more efficient, immense amount of energy is still required to make high grade paper suitable for playing card stock. The complete production process of paper was responsible for 6% of world’s total energy consumption in 2005. The industry uses up to 6.4 EJ (1 EJ = 1x1018 joules!) which is a massive amount. Knowing how big Europe’s role in paper making was in the past, energy accounted 19% of total energy costs in the region. (“Benchmarking energy use in the paper industry: a benchmarking study on process unit level," Andre Faaij/Jobien Laurijssen, Ernst Worrell). Wood pulp is made of cellulose fibers, but high-grade papers use cotton, linen, or hemp fibers. Although mechanical wood pulp produces cheaper paper, businesses that look for playing cards expect higher grade paper, which is retrieved from chemical wood pulping. As the name suggests, a lot of chemicals are used to process pulp to make high-grade paper, which suggests that a lot of internal chemical energy is used along with heat output. The process includes debarking wood and then cooking them with sodium hydroxide and sodium sulphide to remove/dissolve the lignin which is then cut down to fibers (known as Kraft Process). (“Chemical Pulping,” Industrial Efficiency Technology Database). The fibers are then bleached and washed thoroughly. To make paper from this processed pulp, the pulp is squeezed by a series of chain rollers, and then are dried out when passed over steam cylinders. (“How Do You Make Paper from a Tree?”, Wonderopolis). These chain roller presses use a minimum of 12 kW of power. Then, a series of iron cylinders are heated to 100o C, because of which the sheets dry up. Common iron cylinders use 380 volts (finding power/energy consumption is difficult for specific machines). Lastly, a process called “Calendering” is done to make the paper smooth by applying even more heat. Calendering generates up to 3847 MJ of heat from its machine exhaust hood. It is estimated that the combined heat produced during the entire paper-making process is equivalent to 0.6 EJ per year. The paper is then ready and shipped to the playing card company. The next raw material required is ink, so let’s take a look at its production processes and energy usage at each stage.
The process of manufacturing ink is not as simple as one might think, and does have many high energy consuming steps. The production of good ink laid onto playing cards ensures that the playing cards won’t scrape off easily. The image area of the card is coated with an “oily material” that attracts ink and repels water, whereas the non-image area is coated with “material” that attracts water and repels ink. Because of this very specific need, “oil-based” ink is generally used. This oil-based ink is made of petroleum distillate solvent, linseed oil, and soybean oil. The distillate solvent extraction process consumes a good amount of energy. The solvent has to be extracted from oil/lipids from algae. Oil and hexane from the solvent extraction requires distillation and/or evaporation, which in itself is an “energy intensive operation.” Alcohols are also boiled at a high temperature (if necessary) which uses a lot of thermal energy. Unfortunately, hard numeric data is unavailable, only the general idea of energy consumption is found. (“Energy Efficient Process for Solvent Extraction of Oil from Microalgae using Green Solvents,” SBIR.STTR). A large amount of “ingredients” used in the process of simply making the dye, and that ink is manufactured on a large scale, suggests the use of huge machines. Surprisingly, at least in the case of playing cards, inorganic pigments are not used a lot. (“How Ink Is Made”, Mixer Direct). Combinations of dye and pigments (mostly red and black for playing cards) are mixed together with water, linseed oil/alcohol and is heated in a large vessel, until it is dispersed into buttery smooth liquid form. This vessel is heated to an extremely high temperature, proving the large use of combustion energy. Firstly, the carbon black is wetted by the vehicle (a fluid that transports the pigment onto the substrate). This process is called premixing. Since the viscosity of the material is very high, a lot of energy is used to wet the carbon black and premix it. Machines called high-speed dispersers are used for premixing. These dispersers run at a top speed of around 5,000 ft/min by creating a vortex into which “dry ingredients can be added for a quick wet-out.” (“Mix It Up: High Speed Mixers for Paints, Inks & Coatings,” Prospector). Typical motor specification for these dispersers require about 5 Horsepower for every 10 gallons of ink liquid. Energy consumption here doesn’t seem too bad. But for very large high-speed dispersers, 75 to 500 horsepower is needed! (“All about High Speed Dispersers,” Charles Ross & Son Company). The premix is then mixed with excess oil and resin to become more viscous. This is done to disperse the ink particles even further. Keeping in mind that playing cards do NOT use black newspaper ink, black ink must also be treated like a colored ink. The pigment/oil/water mixture at this stage is referred to as “presscake.” A technique called “flushing” is then used in which the oil displaces the water from the surface of the pigment (because pigments have a greater affinity for oil than it does for water.) (“How Ink Is Manufactured”, PressProof). After quality check, the ink solution goes through many filtration steps including finer grinding of the ink particles using either a horizontal mill or a vertical mill (less than 10kWh/t). A final quality check is done and then the ink is ready for transport to the card factory. Overall, although there is no hard-coded energy demand in numeric value, it is evident from the large number of processes, that the energy demands of this step is not small to ignore. Now that the factory has the “main ingredients” to produce high grade cards, we move on to machinery.
On the surface, producing cards might just include cutting the cards into rectangles and printing over them. But in fact, a lot of high-tech machinery is used. The processes used in its manufacturing is what sets apart cheap card decks from high-quality casino-used decks. In recent years, machine sizes are more compressed and more functionable. This means that a single machine could do all stages of production such as lamination, printing metal plates, cutting, and ink printing. The “PK108-110” is a machine developed by JXJLMachinery that takes care of all processes. This ready-made machine can produce 5000 decks per hour, which power consumption of 8.5 KW/hour (“PK108-110 Poker Cards Slitting and Collating Machine”, JXJL Machinery). Traditional factories prefer using single machines per process to keep card decks consistent in quality. Firstly, the two paper sheets are glued together with black glue, and then laminated. Lamination is done by machines similar to “Model: AL 1,” a machine developed by Mark Engineering, which laminates both sides of cards with polymeric plastic films. (Vinyl plastics may also be used by some factories.) The total lamination industry usage is about 1kWh/ft2. Just so happens, a roll of paper is about 30,000 ft. This accounts for 30,000kWh of power use! A lot of lamination takes place in playing cards factories, so this is one of the most energy demanding processes in the card’s production. Some may argue to use “Cold laminators” as they are generally less energy demanding (do not use electricity). But thermal laminators ensure the rubbing of cards will not damage the plastic-coated surface. In this case, energy efficiency and consumption are sacrificed for better quality playing cards. Thermal lamination uses high temperatures, high pressures, and high conveyor belt speeds to employ plastics onto the card’s surface. Next, printing metal plates that acts as a “mold” is made both for the front of the cards and the back. Computerized designs for both the front and the back are perfected and then passed onto machines electronically such as the “Advantage N,” a machine manufactured by AGFA company. This process has to be done only once, since the metal printing sheet can be re-used multiple times. Although the exact type of machines that card factories use is unknown, a number of machines use about 10W of power per hour. This is comparatively a less energy demanding step in the process. These plates are coated with water and are mounted on rolling cylinders inside printing presses. The image area, which was previously coated with oil-like substance, repels this water and is uncoated. The rotary press can print up to 10 decks per second. Oil-based ink is then put onto the plates which prints the card structure on the paper. Special machines are used to print the card papers both sides at once, ensuring there is no mistaken displacement in printing between the front and back. After the completed printing process, only cutting of cards is remaining. Precision-cutting machines cut cards out of the printed sheets into identical sized cards, and are simultaneously stacked into decks. Usually, rotary die cutting machines are used. These machines use dual magnetic cylinders to keep card sheets from slipping whilst cutting. Machines like “Horizon Rotary Die Cutting Machine” manufactured by MSL are generally used on a large scale. After researching a substantial amount, machines used for the cutting process can be easily found, but each machine varies in its energy consumption (unknown), as some machines apply a second lamination layer, while some don’t. Cutting is then continued by chipping the corners of the card decks for consistency. Keep in mind that all these machines are computer powered, and that not only does it use mechanical energy, but secondary source like electricity is widely used in every process. The decks are then pushed into carboard deck boxes and are wrapped with cellophane clear plastics. The usage of cellophane clear plastics is a step toward using lesser energy. It is insane to think that card decks process through so many machines, and can produce about 10 decks per second! The final product is ready for transport!
Since card decks are shipped in bulk, they could be considered “medium” in weight. Cards ship internationally, hence plane transport is most viable. Local transport would most probably use trucks and train. Since this depends solely on distance from the factory to its final destination, calculating total energy consumption can be too complicated. Keeping it simple, energy required for this part would be large amounts of fuels, chemical energy because of the fuels, and mechanical energy (gears and related mechanical devices in transport vehicles). But overall, statistics say that airplanes use about 1116.2 KJ/gallon and trucks use about 3237.9 KJ/gallon. (“Energy Consumption by Mode of Transportation,” Bureau of Transportation Statistics). After customers use it basically till it tarnishes, it is time to dispose of it (or instead, better recycle it!)
Disposal of playing cards is not simple/easy. Playing cards have to be plastic coated for have a smooth slippery finishing. So, this means cards cannot be just thrown away, and require proper disposal. Recycling is possible if plastic bags can be made from the cellulose plastic embedded into the playing cards. Playing cards can be also recycled into tissue paper or toilet paper. Recently, “The US Playing Card Company” - responsible for the production of the world class “Bicycle” playing card decks (used in probably all casinos) - have introduced their “Go Green” card line. This line of cards uses non-toxic vegetable ink on their cards with “sustainably-harvested paper.” These cards can just be recycled like regular paper! (“Bicycle Cards Go Green”, Bicycle). Overall, general stock of playing cards are not recycled, and they are best off kept or disposed. Because of the material of the cards, they can be used in burning flames for various processes, generating high amount of thermal energy. But there are a lot of byproducts from this such as smoke and carbon monoxide, which can potentially lead to the destruction of our earth. Proper containment of the byproducts can be helpful.
In every process from paper and ink production to the final card deck product, there is no better substitute for the human eye for quality check, and for labor. Chemical energy per human at work is therefore a considerable amount (lesser compared to machines) and should not be ignored.
In conclusion, playing cards are a very simple product. But in reality, enormous amount of energy is used in every process leading to the production of the end product. We can only hope that development in technology through the years will increase efficiency of machines responsible for producing playing cards, and also decrease the time it takes to produce one of the most famous pieces of pass-time activities.
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