Electrolux Appliances, Stockholm, received a US patent for a method of operating a laundry machine that relates to improving outcomes when pods are used in the washing process. 

In the patent filing, Electrolux details front- and top-loading machine designs and the difference in operation programs that can be selected by the users or selected automatically.

Issues Identified

Electrolux asserts, in the patent filing, that pods directly inserted into the machine drum can suffer from various shortcomings. For example, it notes that the pod might be dissolved only partially, and it can become trapped within the laundry leading to incomplete or inefficient cleaning and the formation of spots or stains on the laundry. The pod also can become trapped in or on the bellows seal that surrounds the drum door, which also leads to incomplete or inefficient cleaning, and pieces of undissolved pod pouches can often remain in the laundry or in the bellows, notes Electrolux.

Electrolux also notes that a pod loaded into the drum can begin to dissolve and release the active ingredients before the washing cycle begins. And, if the washing cycle starts with a draining phase, which Electrolux says is typically performed for safety and/or hygienic reasons at the beginning of the cycle, some of all of the active ingredients of the pod may be flushed away.

Electrolux’s patent also details another issue: if the washing cycle begins after a delay following insertion of the pod, the pod may break down or its pouch may dissolve before the washing cycle begins, resulting in undesired spots or stains on the laundry due to contact of the highly concentrated detergent emitted from the pod with the load of laundry. When this happens, the detergent also may fall to the bottom of the drum and be washed away during an initial draining cycle, notes Electrolux in its patent filing.

Lastly, Electrolux notes that the effective time of breakage of the pod and the release of detergent cannot be accurately predicted, which means the cleaning cycle cannot be optimized to provide the desired duration of contact between the detergent and the laundry.

In the patent, the appliance maker notes that it has developed alternative laundry washing machines that address but notes there remain “shortcomings.”

In one example, Electrolux notes a system in which the pod can be flushed from a multipurpose additive drawer to a sump located below the tub. Here the pod’s contents mix with water to provide a more dilute and uniform cleaning solution before being deposited on the laundry. This does not rely on the pod being actively broken apart by water jets, but instead on conventional dissolution of the pod’s water-soluble outer membrane.

But according to Electrolux, different pod compositions may take different amounts of time to passively dissolve, and the overall time of the wash cycle may need to be increased to accommodate such passive dissolution to ensure complete mixing of the detergent.

Electrolux’s New Patent

The company’s patent addresses these issues. US Patent No. 11,713,531 B2 (Allison White, Yihong Li, Oscar Madalena)—comprises the following steps:

• receiving a unit dose package water soluble pouch containing cleaning product in a soaking chamber;
• operating a processor to provide a first quantity of liquid to the soaking chamber;
• operating the processor to allow the first quantity of liquid and the unit dose package to remain in the soaking chamber for a predetermined amount of time sufficient to at least partially dissolve the unit dose package; and
• operating the processor to release a solution (that includes an entirety of the unit dose package and at least the first volume of liquid) from the soaking chamber into a washing tub after the predetermined amount of time has elapsed.

Who Is Electrolux?

Electrolux Group is a leading global appliance company that has been active for more than a century.  Based in Stockholm, Sweden, and listed on Nasdaq OMX Stockholm, in 2022 Electrolux Group had sales of SEK 135 billion (about $12.5 billion at current exchange rates) and employed 51,000.

In addition to laundry machines, Electrolux also manufactures refrigerators, freezers, ovens, dishwashers, tumble dryers, vacuum cleaners, air conditioners, air purifiers and small domestic appliances. The company’s brands include Electrolux, AEG and Frigidaire.

Electrolux says its sells more than 60 million household products in over 120 markets each year.

Last August,  Electrolux’s premium brand AEG announced a new range of washing machines and tumble dryers that automatically adjust time, water and energy usage. In addition, the unit’s new add-on filter catches up to 90% of microplastic fibers released by synthetic clothing, according AEG, which unveiled the new machines at IFA in Berlin on September.

More on Laundry Detergent from Happi

For insight into formulating liquid laundry detergents, see this article from industry expert Shoaib Arif.

An in-depth report on market trends and news in fabric care can be accessed in our January 2023 issue.

More patents related to household and personal care can be found here.

To purchase ingredients to produce laudry and fabric care products, see Happi's Buyers' Guide.

Looking for a contract manufacturer to produce your next laundry/fabric care product? Happi's Contract Packaging & Private Label Directory is a great place to begin. Here is the section to find producers of liquid laundry detergents.