#253 | Organizing the flow of heat around bento ice packs | Giving shape to "What if?" [03_Prototype_74]

Today's theme is

"Bento ice packs"

In the consideration phase, I thought of three types of support:
1. Being able to adjust the area that receives heat
2. The direction of heat reception is naturally determined
3. Maintaining a constant distance from the food
This time, I will try to give shape to each of these supports from the perspective of "What if?"

[Time to prototype]

1. Being able to change the area that receives heat
Instead of placing the ice pack directly against the bento box,
I thought of a shape that fits into a cover
that has a sliding window on the food side.
By widening or narrowing the range of the window,

I thought I could create a difference in the speed
at which heat is transferred to the ice pack.

When you want to slow down the heat transfer, make the opening range smaller.
When you want to receive heat from a wider surface, make the opening range wider.
Even if the ice pack itself is the same,
I thought about whether I could adjust how heat is transferred

depending on the area opened toward the food side.

2. The direction of heat reception is naturally determined

I thought of a shape that receives as little excess heat as possiblefrom the side close to the outside air,
while receiving the necessary heat from the food side.
Cover the outside air side of the ice pack
with an insulating material.
Keep the food side open facing downward

as the surface to receive heat.

3. Receiving heat while also catching condensation
I thought of a shape that covers the food side of the ice pack
with a thin, absorbent sheet.

Instead of wrapping it in thick cloth,
provide only one layer that adheres to the surface of the ice pack.
It does not significantly hinder heat transfer,
and catches any condensation that occurs right there.

Receiving heat firmly from the food, and
not spreading water droplets inside the bag.
This is a support to maintain both as much as possible.

[What if we implemented this?]

1. Changing the opening area with a sliding window
When actually making it,
a mechanism is needed to stop it at several stages,
such as small, medium, and large,
so that the window does not move on its own while carrying it.

It is also important not to damage the ice pack with the edge of the cover.
How much it needs to be opened to maintain the necessary coldness
needs to be confirmed while comparing temperature changes under the same conditions.

2. Aligning the insulation surface and the food side direction
For the material covering the outside, thin foam or
aluminum vapor-deposited sheets can be considered.

To ensure the food side naturally faces downward,
there might be ways to make the bottom side slightly heavier, or round the top surface
and make the bottom surface flat.

However, when the bag tilts,
the orientation may not necessarily return just by weight.

Ingenuity to make it hard to get the orientation wrong is also necessary,
such as changing the texture on the front and back, or adding a guide that makes it difficult to fit in the opposite direction.


3. Layering a thin absorbent sheetFor the material, rather than absorbent polymers,
it seems better to try thin cellulose-based non-woven fabrics or absorbent paper.
Since making it thick will make it difficult for heat to transfer,
make it a single layer that adheres to the surface of the ice pack.
It is also necessary to check whether it shifts or peels off
after absorbing moisture.

Is it replaceable, or is it washed and reused?
I also want to think about how to handle it so that fibers do not fall off
and it is not stored while wet.
While maintaining the necessary coldness,
can we reduce excessive cooling in only some parts,
and water droplets spreading into the bag?

There seem to be many challenges!!

[✍️Summary]

Ice packs are essential for carrying bento boxes in the summer.

When I added an ice pack that came with takeout food, the pack tore and became sticky,
or when I added a large ice pack,
the rice became too hard.

Based on that experience, this time,
instead of changing the performance of the ice pack itself,
I looked at its surroundings.

I thought of a sliding window that changes the range opened toward the food side,
an insulation surface that separates the roles of the outside air side and the food side,
and a thin absorbent sheet that catches condensation without hindering heat too much.
Instead of making the ice pack harder to melt,

while firmly receiving the necessary heat,
I organized how heat is transferred and how water droplets spread.
Implementation requires confirmation of temperature changes and water absorption, but

I thought that even the invisible flow of heat
could be supported by the shape of the surroundings.
Thank you for reading again today!



#Prototype

#IcePack
#Bento
#CoolerBag
#SummerVacation
#Food
#Heat
#Living
#LifeWithChildren
#Tools
#DailyNecessities
#Design
#ProductDesign