Recently I’ve been working on recreating Kenner’s* Ecto-Plazm* recipe and I’ve learned enough about it to warrant sharing the results, and maybe others can help crack some of the remaining issues.
A picture of a ghost with some slime on him;
Key Elements Left to Solve
Any product made with water needs a Preservative or it will quickly go bad. I have no leads as to what kind of Preservative Kenner used in* Ecto-Plazm*, but I’m soon going to start experimenting with those I can obtain. I know there are people who make and sell their own paint and make-up, and the same preservatives used there should translate to Slime (I imagine).
The Smell; All of the ingredients in Ecto-Plazm, and indeed most any Toy-Slime are virtually odorless. There’s a feint smell to the guar, but this would be easily masked by the somewhat light odor of Kenner’s slime. At this point I have to conclude that the smell of Slime is artificially created.
Thinking back, I can only speculate as to why Toy-Slime smells. It’s entirely possible there are regulations or guide-lines stipulating they have a smell to deter kids from eating the stuff. Or maybe Kenner just thought Slime should smell (I would agree).
Regardless, I currently have no leads as to how to go about breaking down the smell of* Ecto-Plazm*, or recreating it.
The Secret of the Ooze
The basic recipe of slime has been described here for several years now; http://www.chymist.com/guar%20gum%20slime.pdf
These were the original elements of slime, but this will not result in “Ecto-Plazm.”
Slime was developed by Mattel in the 70’s and they went on to sell their formula to Kenner and other toy manufacturers when toy-slime surged in popularity. Each manufacturer would then tailor their own recipe to create a unique product.
Determining the Unique Properties of Ecto-Plazm
It’s important to realize that these toy-slimes will break down over time. In the case of home-made slime, shelf life is only going to be a day or two because we don’t have access to the preservatives that the toy companies used.
As the slime breaks down it will lose it’s non-Newtonian properties and revert to a normal liquid.
I have a few cans of unopened (until I opened them) Kenner* Ecto-Plazm*, and can attest that over the last three decades the slime has slowly become… soupier. This significantly impacts the playability of the slime. Pouring a can down the Firehouse’s Goop-Gates today would likely result in an irrecoverable mess.
This makes replicating the exact sliminess of Ecto-Plazm more difficult. With human memory being unreliable I’ve taken to looking at old photos and toy commercials featuring Ecto-Plazm to get an idea of the toy-slime’s properties such as strength, viscosity, elasticity, and brittleness.
Ingredients
- **Guar Gum Powder
20 Mule Team Borax
Pure Glycerin
Water
Food Coloring (get the Basic and Neon colors)
Washable Tempera Paint (White)**
**You will need an Electric Mixer and a measured syringe or pipette. **
This is the exact Guar that I purchased; http://www.ebay.com/itm/Guar-Gum-Powder-1-LB-Bulk-Packaging-/201183033192?
It’s listed as food grade. As I understand it “food grade” guar is less powerful than “science grade,” but it is also easier to obtain. Whether or not all “food grade” guar is relatively the same I do not know.
Borax is available at most any grocery store on the laundry isle.
Glycerin is sold as a food additive in well stocked grocery stores, but I had a much easier time finding it in drug stores sold as a skin protectant. You can get “Pure Glycerin” at any CVS or Wal-mart. (Glycerin is also commonly found in personal lubricants which is why you see some slime recipes based around lube)
Color and Opacity
Coloring the Slime will be the first step in the process. You simply color your water and whatever appearance you create will translate to the finished slime.
My recommendation for coloring is simple and affordable; Use a combination of food coloring and white tempera paint. The food coloring creates the color, the paint controls the opacity.
If you want a translucent slime like that of the movies food coloring alone will achieve this. Adding in small amounts of white paint will give you the opaqueness of Kenner’s Ecto-Plazm. I find I like something in between.
Color Supplementary
I don’t have a precise measurement for the color because this is done to ‘taste.’ I like to color every batch of slime a bit different. Still, I worked on the coloring process for quite a while until I was satisfied that I could faithfully recreate the appearance of the four original colors of Ecto-Plazm.
There are alternatives to the method I listed so I’ll discuss what I’ve tried. Using paint alone can yield a more vibrant color, but this is more expensive. I’ve tried powder paints (they come from India and are used in those color-run marathons), these can give extremely vibrant colors, but again are much more expensive and I’ve had some issues with the colors turning. Powder Paints can also be scented.
Crayola finger paints are available everywhere, are very affordable, and offer a lot of colors. Unfortunately they are scented.
Do You Smell Something?
Be aware that many of the color agents you may choose to use could be scented. This scent will carry over into your slime. This may not bother you, but I can’t stand an artificially flowered aroma coming from my slime. It breaks the illusion. And If I ever replicate the aroma of Kenner’s Ecto-Plazm any existing scent would ruin it.
It’s Slime Time
Here are the base ingredients listed again with measurements;
- **400ml of pre-colored hot water.
1 teaspoon of Guar Gum Powder
1.5 teaspoons of Glycerin
2.5ml to 4ml of Borax Solution**
To start, run hot tap water to be colored. We need 400ml to make the slime so use an excess of that while you’re coloring it. If your color is too opaque or too dark feel free to add more water. When you’ve got the appearance right pour out 400ml into a mixing container and discard the rest.
Measure out precisely 1 teaspoon of Guar Gum. When I developed this recipe I measured everything by scale and then reversed the amounts of everything else so that I could use a base measurement of Guar, exactly 1 teaspoon.
Place the guar into a small container, something like a shot glass or one of those tiny Dixie cups. It will be difficult to properly sift the guar straight out of the spoon.
Mix the guar into the colored water. You will need an electric mixer for this. Guar is very difficult to work with, you need to sift it into the water in small amounts, but do so consistently and relatively quickly (over 30 seconds or so) while mixing the water.
I use a traditional 2 pronged mixer for this but I only use 1 prong. It takes a little practice to get it mixed without any clumping. If you have a small amount of tiny clumps these can be strained out of the mix. If you end up with any large clumps you’ll have to start a new mix from scratch. Once the initial guar has started to thicken it will be impossible to mix more guar in without it clumping.
With practice you should be able to get all of the guar to dissolve into water, it will begin to thicken quickly. Set it aside for 15-20 minutes.
Add in 1.5 teaspoons of Glycerin and mix thoroughly. The Glycerin is a key element to the formula. Without it the slime will appear very much like jello. Glycerin gives the slime its extreme elasticity, making it sticky and allowing it to bubble up.
Make a Saturated Borax solution by putting a few tablespoons of Borax into a cup, and add water. Mix thoroughly. When the water is saturated the remaining Borax will no longer dissolve and sinks to the bottom.
Using a syringe or a pipette, suck up 2.5ml to 4ml of the Borax Solution. Eject it slowly into your slime while mixing it. The chemical reaction the Borax causes will be very quick, but continue to mix it. You’ll need to hold onto your container now as the slime thickens.
The more Borax you use the stronger your Slime will be, but at the cost of stickiness and elasticity.
At 2.5ml, you’ll get a nice soupy, sticky slime.
At 3ml, you’ll get something very close to the original Kenner Ecto-Plazm.
At 4ml, you’ll really notice the ‘solid’ qualities of the slime. You can quickly pull the entire 400ml out of its container, but it will then immediately ooze out of your hands. This is a very playable slime, it gives you time to work with if you’re taking photographs of it, and is easier to clean up.
That’s all for now, I didn’t intend to write all this. What the hell.