LCA of Printer Cartridges Life Cycle Analysis and Environmental Impact of Printer Cartridges

Printer cartridges are an important part of the world in which we live. Every day we purchase them, use them, and eventually need to replace them. The objective of this study is to examine the life cycle environmental impacts of printer cartridges. This assessment will not examine a particular type of printer cartridge, but will consider the life cycle of a printer cartridge to be relatively homogeneous. The exception will be in the case of remanufactured cartridges. The goal of this study is to understand the environmental impact of printer cartridges along every state of their product lifecycle.

Functional Unit

ISO standards dictate that the functional unit of the system should be designed so that the inventory results can be understood on the basis of its function. The functional unit serves the purpose of making certain that various units printer cartridges can be compared on the same quantitative basis (First Environment, Inc., 2004). A functional unit reflects usage of the item, rather than the quantity of materials that goes into it. In the case of printer cartridges, a functional unit that is defined in terms of the function of the system. Various printer cartridges can print different numbers of pages per individual cartridge. Therefore, a standard unit must be defined a more clearly allows a comparison of different cartridges. The cartridge functions to produce a certain number of usable pages. Therefore, the functional unit for the study will be the printing of 100 useable single color, single sided pages.

Boundaries and Modeling

The cartridge has several stages included in the system boundaries. The stages are production, distribution, use, and end of life. More precisely, these boundaries will be defined as follows.

1. Production -- the production phase is defined as a production of the materials that go in each cartridge and its assembly. Transportation may be needed from suppliers to the manufacturing facility. This includes the extraction of metals and production of plastics that go into every component of cartridge manufacture.

2. Distribution -- refers to delivery of the finished product to the end user. This includes energy for warehousing and transportation costs.

3. Use -- this refers to operation of the cartridge by the end user. This use is defined as printing requirements including paper and a printer needed to print 100 useable pages.

4. End of life -- this boundary refers to the fate of the cartridge after the toner in it has been used up.

This study compares a single cycle in the life of the cartridge. Companies are taking different approaches to the problem of toner cartridges. Some of them, only offer cartridges that have not been recycled, but that are brand new. Others have programs for recycling the cartridges and these cartridges can go through multiple stages. Different stages of the product lifecycle may require different levels of transportation, which may add carbon expenditures to the process, making the recycling of toner cartridges a bigger environmental impact than simply using them and then throwing them away. This study will explore this issue as part of this life cycle study.

Inventory Analysis

It is necessary to understand that there are two different types of cartridges. The first type is inkjet and the second type is a xerographic toner. Both serve the same purpose for the end customer. The xerographic toner uses toner powder and the ink cartridges use liquid ink (Nelson., Carney, & Wille-Irmiter, et al., 2011). The following will explore the inventory for both types of cartridges.

. Components. The life cycle inventory analysis for an Inkjet printer cartridge involves only a few materials. Cartridges consist primarily of polyethylene terephthalate (PET), glass-filled polyester and electronics (Ord & DiCorcia, 2005). It also contains an ink, Every cartridge company has its own special ink formula and this information is not available to the public. On the material flows for these elements cannot be determined for the purposes of this project (Ord & DiCorcia, 2005).

A survey of material safety data sheets of various ink and toner cartridges was able to determine the most common materials...

However, in general, ink and toner compounds include styrene acrylate copolymer, polymethyl methacrylate (PMMA), iron oxide, amorphous silica, carbon black, paraffin wax, diethylene glycol, and 2-pyrrolidone (Nelson., Carney., & Wille-Irmiter, et al., 2011). These elements have different energy inputs and different byproducts and wastes associated with them.
The largest component, which makes it nearly 80% of the mixture used in toner is styrene acrylate copolymer. This is a resin that is manufactured by a chemical processor. Magnetite is the iron oxide used in toner cartridges. It also doubles as a pigment. Carbon black is using both toner and ink as a pigment. The manufacture of this product requires the burning of hydrocarbons at extremely high temperatures in order to obtain elemental carbon (Nelson., Carney., & Wille-Irmiter, et al., 2011). Polymethyl methacrylate (PMMA), diethylene glycol, and 2 pyrrolidone are petroleum products (Ahmadi, Williamson, & Theis, T. et al. 2003). One could get into all of the various minor components of the printer cartridge, but there is not sufficient room to address all of them in this study.

The toner cartridge has three main parts, the hopper which holds that toner powder, the developer unit which has an assortment of negatively charged magnetic beads, a drum that the needs are attached to, and the revolving drum that coats the entire sheet of paper with a positive electric charge. A laser removes the positive charge and places where the image is going to be printed. This leaves behind a negative electrostatic image. The key compound that carries a positive charge is iron oxide. The negatively charged beads pick up the toner from the hopper. The toner is attracted to the places where the laser created a negative image. Before the image is printed out it goes to a pair of heated rollers (Nelson., Carney., & Wille-Irmiter, et al., 2011).

Inkjet cartridges work in a slightly different way from toner cartridges. The ink is contained in a foil lined compartment. The cartridge deposits ink onto the paper through the use small jets. A silicon chip contains etchings that act as hydraulic jets. These are connected to a metal plate beneath the ink compartment. Electricity passes through the metal plate and super heats the silicon chip. This causes a small amount of vaporized ink to be released through these etchings. The pictures are made through the use of dots on the paper that are smaller than a human hair (Nelson., Carney., & Wille-Irmiter, et al., 2011).

Packaging. Cartridge packaging must also be included in the materials inventory of a printer cartridge. The packaging includes paperboard, cartons, brochures, and any other material included in the packaging. The approximate weight of this packaging is 27 g. Many printer cartridges also come in a hybrid plastic/foil pouch that weighs approximately 1 g (Ord & DiCorcia, 2005).

Post consumer waste. Post consumer waste refers to consumables that the customer must throw away throughout the lifecycle of the product. These typically include packaging for the printer cartridge and the cartridge itself. It was found that the laser multifunction printer produces nearly five times as much post consumer waste as a solid ink multifunction printer (Nelson., Carney, & Wille-Irmiter, et al., 2011).

Impact Analysis

Previously conducted Life-Cycle analyses contain large discrepancies and a lack of high quality data regarding transportation and packaging (Bousquin,, Esterman, & Rothenberg, 2011). The problem is determining upstream cutoffs while conducting the LCA. The production and use stages are easier to document. However, the end of life stage represents another area where there are major discrepancies in data and in conclusions (Bousquin,, Esterman, & Rothenberg, 2011).

This study examines printer cartridges in general, rather than a particular brand or type of printer cartridge. This may be one reason for discrepancies in the life cycle analysis. Transportation and end of life tasks for various printers are different. Therefore, for the purposes of the study it is difficult to make assumptions and generalizations based on the information that is available. More detailed information is necessary in order to be able to accurately assess these portions of the life cycle analysis.

Post consumer wastes are consumables and packaging that the customer must dispose of over the life of the product. Xerox found that a solid ink printer creates approximately 90% less post consumer waste than a laser printer (Bozeman, DeYoung, & Laitko, et al., 2010). Post consumer waste differs according to the type of toner cartridge or ink cartridge. For the most part, many of them are the same. Those that use recycled fiber board packaging have a lower impact on the environment than those that use plastic containers on the inside of the cardboard packaging. The more recyclable material and a more biodegradable material that is used the lower the impact on the environment.

Transportation and electricity use play a key role in the life cycle analysis. Electricity use begins…