# How are papier-mache egg trays manufactured?

**URL:** <https://boards.straightdope.com/t/how-are-papier-mache-egg-trays-manufactured/100357>\
**Category:** Factual Questions\
**Created:** [March 27, 2002, 11:24am UTC](https://boards.straightdope.com/t/how-are-papier-mache-egg-trays-manufactured/100357 "2002-03-27T11:24:38Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\
**Post date:** [March 27, 2002, 11:24am UTC](https://boards.straightdope.com/t/how-are-papier-mache-egg-trays-manufactured/100357/1 "2002-03-27T11:24:38Z")

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I would like to know the details of the process of manufacturing papier-mache egg cartons and trays.

I’m not unfamiliar with the general concepts of making paper products; pulping and so on.

I have noticed that the trays have a smooth side, which retains the impressions of what appears to be a fine mesh, and a rough side which looks fairly unprocessed; what I specifically would like to find out is whether the pulp is formed onto shaped mesh or whether it comes off the mesh as a flat sheet and is pressed into shape.

Also I would like to know about the method of drying; are the finished products dried naturally, or by heat/vacuum?

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**Author:** ![bbeaty](https://avatars.discourse-cdn.com/v4/letter/b/c0e974/32.png) [@bbeaty](https://boards.straightdope.com/u/bbeaty)\
**Post date:** [March 28, 2002, 12:59am UTC](https://boards.straightdope.com/t/how-are-papier-mache-egg-trays-manufactured/100357/2 "2002-03-28T00:59:07Z")

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> [@](#):
>
> \*Originally posted by Mangetout \*  
> **I would like to know the details of the process of manufacturing papier-mache egg cartons and trays.**

I saw something about this long ago. The porous forms are dipped into a vat of paper pulp, then low pressure is applied briefly to the inside of the form in order to “suck” water out of the adjacent pulp so that a layer of the desired thickness builds up. I would imagine that the forms then go to a drying oven, but that I don’t remember exactly.

It’s vaguely similar to slip-casting of clay objects, where liquid clay is poured into a dry mold and then poured out again. The dry mold “sucks” water out of the clay, and a hard layer builds up.

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**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\
**Post date:** [March 28, 2002, 5:51am UTC](https://boards.straightdope.com/t/how-are-papier-mache-egg-trays-manufactured/100357/3 "2002-03-28T05:51:19Z")

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[This company](http://www.hawkpak.com/MachineBuilding.htm) dips moulding dies into the pulp and applies vacuum to make the product.  
“The wet product is placed on a conveyor and sent through a drying tunnel (often gas fired).”  
They have a few pictures of pulp moulding machinery [here](http://www.hawkpak.com/CompanyProfile.htm).