Does hand dishwashing liquid degrease as well as add "grease"?

When preparing a copper etching plate for etching, it must be degreased completely before putting on the etching ground. Otherwise the acid may "bite" through the ground ("foul biting") in spots not desired. Whiting has been used for degreasing and alcohol has also been used successfully. I was wondering whether using hand dishwashing liquid as a preliminary measure (before the alcohol or whiting) to remove oil-based ink and other substances both degreases -- as I think it may do when washing dishes -- but also adds "grease."




There is a large set of chemicals which either can act as a moisturizer and/or emollient *by chance*, or which are intentionally added to the detergent for this function. You find them in cosmetic shampoos, as well as dishwashing liquids advertised as "especially friendly to the skin of your hands". It can be difficult to get rid of them, one reason why labs active in analytical chemistry (e.g., characterization of surfaces)\* are careful when using them / their dishwashers *finally* rinse the glass ware with deionized water.


To extend Poutnik's answer, the typical suspects are (for example) palmitates, stearyl alcohol and stearyl ethers, squalene, decyl esters, polyethylene glycols (PEG). There equally are some telling *generic names* for them e.g., [lamesoft](https://carecreations.basf.us/products/lamesoft-balance) (BASF), or [tegosoft](https://personal-care.evonik.com/en/tegosoft-ac-the-vegetable-based-emollient-with-a-light-skin-feel-101788.html) (evonik). At small scale, you can remove them with clean distilled water, followed by a rinse with e.g., isopropanol/rubber alcohol.




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\* Surface tension, wettability of surfaces, shape of drops sitting on surfaces relate to surface energies, a topic in physical chemistry. One approach to characterize them is literally to place a drop on a surface and to check its shape:


[![Macro photograph of two droplets, with blue construction lines next to the left-hand one showing the contact angles. The caption reads: Figure 2. Representative image of contact angles before (left) and after epicuticular wax removal (right) from collard leaf.](https://i.stack.imgur.com/bTqYY.png)](https://i.stack.imgur.com/bTqYY.png)


(edit of an image by Chiu *et al.*)


Especially with the advent of cell phone cameras, this is an affordable experiment for the undergrad labs. As reported by Chiu *et al.*, students take a couple of photos, fed them into the freely available [ImageJ](https://imagej.net/ij/index.html) program supplemented by the plugin about [contact angles](https://imagej.net/ij/plugins/contact-angle.html) (a [link to youtube](https://www.youtube.com/watch?v=eLzcRvFneTM) for a brief tutorial), and determine the contact angle (enclosed by the blue straight lines added to the illustration above). Recording multiple drops per sample improves your evidence by statistics, especially if comparing different samples/PCBs.


For process/quality control, one can hence imagine to record this characteristic angle between a surface of a reference sample deemed *clean enough*, and distilled water. On any subsequent PCB, one would drop again a drop of distilled water to record anew a couple of photos (and by this, contact angles) about different spots as a check before the board enters the next stage of soldering, coating, etc.


Chiu, Y.-C.; Jenks, M. A.; Richards-Babb, M.; Ratcliff, B. B.; Juvik, J. A.; Ku, K.-M. Demonstrating the Effect of Surfactant on Water Retention of Waxy Leaf Surfaces. *J. Chem. Educ.* **2017**, *94*, 230–234; [doi 10.1021/acs.jchemed.6b00546](https://doi.org/10.1021/acs.jchemed.6b00546).


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Total "degreasing" of skin is undesired and would be harmful in long term.


For that reason, skin washing formulas contain auxiliary components, partly lipophilic, intended to adhere on skin and regulate the level of skin "degreasing". And they partly "distract" the surfactant not to do skin fat emulgation so thoroughly.


The overall effect interferes with the goal to have clean surface.


It is better to use formulas advised to use with gloves (like liquid formulas for manual dishwashing).


Or even better - using pure surfactants intended for labs (like sodium laurylsulfate, or some biodegradable alternatives).


Or, organic solvents as mentioned, but then there can be material-solvent compatibility issue.


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