NEIGE ARTIFICIELLE ET METHODE DE FABRICATION CONNEXE

ARTIFICIAL SNOW AND METHOD FOR MAKING SAME

Abrégé français

Un produit de neige artificielle, non toxique et à faible empreinte environnementale, est fait par extrusion d'un mélange d'amidon, d'alcool polyvinylique et de talc pour former un produit d'amidon extrudé et pulvériser le produit d'amidon extrudé en fragments. Les fragments peuvent être triés selon leur taille. Un colorant peut être ajouté pour produire des flocons de neige artificielle en diverses couleurs festives.

Abrégé anglais

A non-toxic, environmentally benign artificial snow product is made by extruding a mixture of starch, polyvinyl alcohol and talc to form an extruded starch product and smashing the extruded starch product into fragments. The fragments may be sorted by size. Colorant may be added to yield artificial snow flakes in various festive colors.

Revendications

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CLAIMS:
I. A non-toxic, environmentally benign artificial snow
comprising the fine fragments of a material smashed and size-
sorted extruded from a mixture comprising:
starch 80% to 90% by volume;
polyvinyl alcohol 10% to 15% by volume;
talc 0% to 2 1/2% by volume; and
hydrogenated soy flakes 0% to 2 1/2% by
volume.
2. The artificial snow material according to claim 1 comprising
a colorant (0% to 5% by volume).
3. The artificial snow material according to claim 2 wherein the
colorant is a food coloring.
4. The artificial snow material according to claim 2 wherein the
colorant is a food coloring is selected from the group consisting of
pink, red, green, blue and yellow.
5. The artificial snow material according to claim 1 having a
water saturation of up to 13%.
6. The artificial snow material according to claim 1 wherein the
starch is native potato starch.
7. The artificial snow material according to claim 1 wherein the
polyvinyl alcohol is finely powdered.

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8. The artificial snow material according to claim 1 wherein the
polyvinyl alcohol is finely powdered, with a particle diameter of
no more than 10um on average.
9. The artificial snow material according to claim 1 having a particle
size less than 3/4 inch.
10. The artificial snow material according to claim 1 having a particle
size less than 3/8 inch.
11. The artificial snow material according to claim 1 having a particle
size no more than 1/8 inch.
12. A method for making artificial snow comprising:
extruding a mixture comprising starch (80% to 90% by
volume), polyvinyl alcohol (10% to 15% by volume) and talc (0%
to 2 1/2% by volume) to yield an extruded product;
smashing the extruded product into fine fragments; and
sorting the fine fragments by size.
13. The method of claim 12 wherein the mixture comprises
hydrogenated soy flakes (0% to 2 1/2% by volume).
14. The method of claim 12 wherein the mixture has a water saturation
of up to 13%.
15. The method of claim 12 wherein the polyvinyl alcohol is finely
powdered, with a particle diameter of no more than 10um on
average.
16 The method of claim 12 wherein the artifical snow has a particle
size less than 3/4 inch.

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17. The method of claim 12 wherein the artifical snow has a particle
size less than 3/8 inch.
18. The method of claim 12 wherein the mixture comprises a colorant
0% to 5% by volume).
19. The method of claim 12 wherein the extruded product is smashed
by causing it to fall onto a blunt-edged blade, forming fine
fragments.
20. The method of claim 19 wherein the fine fragements are sorted by
at least one screen.
21. The method of claim 19 wherein the fine fragements have particle
size of between 1/8 and 3/4.
22. The method of claim 12 additionally comprising packing the fine
fragments in an anti-static package.
23. The method of claim 22 wherein the anti-static package comprises
a bag having an outer layer, an inner layer and an electrically
conductive anti-static layer between the inner layer and the outer
layer.
24. The use of the composition of any one of claims 1-11 as an
artifical snow, packaged and labelled for such use.

Description

CA 02522942 2005-10-07
ARTIFICIAL SNOW AND METHOD FOR MAKING SAME
Technical Field
[0001] This invention relates to artificial snow which may be used,
for example, for seasonal decoration, to adorn sets for theater and movie
productions, and the like. The invention also relates to a method for
making artificial snow.
Back r
1 O [0002] Artificial snow is used for seasonal decoration of homes and
businesses as well as for standing-in for real snow in theater productions,
movie sets, and the like. Artificial snow may also be used in the
production of advertisements and other commercial artwork. A good
artificial snow resembles natural snow in texture. Where the artificial
snow will be dropped from above to simulate falling snow, it should drift
downwardly in air relatively slowly in a manner that resembles the falling
of natural snow.
[0003] Artificial snow is often displayed in places accessible to
children and other members of the public, for example, in seasonal
displays in businesses, homes and the like. The inventors have determined
that there is a problem with some materials which have been used
previously for artificial snow because these materials can be toxic, if
ingested, and can also disturb the environment.
[0004] The inventors have identified that there is a need for a high-
quality artificial snow which is environmentally benign and non-toxic.
Brief Description of Drawings
3 O [0005] In drawings which illustrate non-limiting embodiments of the
invention:
Figure 1 is a block diagram of a production line for artificial snow
according to an embodiment of the invention;

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Figures 2A and 2B are respectively a partially schematic elevation
sectional view and a partially schematic plan sectional view of a device for
making artificial snow according to an embodiment of the invention; and
Figure 3 is a cross-section through a bag for packaging artificial
snow.
Description
[0006] The inventors have ascertained that a highly satisfactory
artificial snow product that is non-toxic and environmentally benign can be
1 O made by combining the following ingredients (all percentages by volume):
~ starch 80% to 90% by volume;
~ polyvinyl alcohol 10% to 15% by volume;
~ talc 0% to 2 %2% by volume;
~ hydrogenated soy flakes 0% to 2 %Z% by volume; and
~ colorant 0% to 5% by volume.
[0007] The starch may be provided in the form of native potato
starch. Native potato starch is available, for example, from Avebe Starch
of Veendam, Netherlands.
[0008] The polyvinyl alcohol is preferably finely powdered. In a
preferred embodiment, the polyvinyl alcohol is provided in the form of
particles having diameters of approximately 10 ~,m.
[0009] Figure 1 shows an example production line 10 for making
artifical snow according to one embodiment of the invention. Production
line 10 has a source of starch 11, polyvinyl alcohol 12 and talc 13. These
materials are mixed, for example, in an electric mixer 16, and fed into an
extruder 18.

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[0010] Water mixture 20 is added in extruder 18 to achieve suitable
extrusion of the starch mixture. In an example embodiment of the
invention, the starch mixture is extruded with a water saturation of up to
13%. In this example embodiment of the invention, the extrusion is
performed at 170° C and 600 psi through a 1 mm die.
[0011] The resulting extruded starch material has a crisp outer skin
and an internal cellular structure that is highly porous and irregular. The
extruded starch has a density of approximately 340 to 380 grams per cubic
1 O foot. The extruded starch has the form of a somewhat irregular cylindrical
extrusion roughly 3/4 inch in diameter.
[0012] In some instances it is desirable to make colored artificial
snow. Colored artificial snow may be used to create special visual images
1 S in theater or film productions. Colored artificial snow may also be used
for seasonal decorations of various kinds. For example, pink or red snow
could be used as part of Valentine's Day decorations; green artificial snow
may be used for St. Patrick's Day decorations; pink, blue and yellow may
be used for Easter-themed decorations; and so on.
[0013] Within a method for making artificial snow according to the
invention, it is possible to add a colorant 22 to cause the artificial snow to
be colored. Food coloring is a suitable non-toxic colorant. A suitably
colored food coloring may be mixed with the water injected in extruder 18
during the extrusion process to cause the extruded starch product to be
colored. The amount of food coloring or other colorant 22 added can be
selected to achieve a desired intensity of color. The amount should not be
so great as to affect adversely the texture and quality of the extruded starch
product.

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[0014] The extruded starch product, as extruded through a lmm die,
is approximately 3/4 of an inch in diameter. The material is cut into small
pieces in a cutter 26, for example, approximately 2-inch long pieces.
Cutter 26 may be integrated with extruder 18. The cut material is
conveyed to a storage hopper 30. The extruded starch product is allowed
to cool to ambient temperature.
[0015] The extruded starch product is then processed to make
artificial snow. This may be done by smashing the extruded products in
1 O smasher 32 and then sorting the resulting fragments by size in a size
sorter
34. Figures 2A and 2B are views of apparatus 40 that combines the
functions of a smasher 32 and a size sorter 34.
[0016] In apparatus 40, the extruded starch product is dropped into
hopper 42. The extruded starch product is allowed to fall past a blunt-
edged blade 46 of approximately 6 to 8 inches in diameter rotating at a
speed in the range of, for example, 6,000 to 10,000 rpm. A speed of 8,500
rpm has been found to be satisfactory. As the extruded starch pieces fall
past the rotating blade 46 they are smashed into small fragments. The
fragments fall through a screen 50. The size of the apertures in screen 50
may be selected depending upon how coarse or fine it is desired to make
the artificial snow. Larger apertures result in coarser artificial snow
flakes.
Smaller apertures result in finer artificial snow flakes. The screen 50 may,
for example, have apertures in the range of 3/8 of an inch to 3/4 of an inch
in size. Sorting the fragments by size may comprise removing fragments
that are larger than or smaller than a threshold size from the fragments.
[0017] The starch fragments fall into a channel 52. The fragments
are urged along the channel 52 by a flow of air 54 delivered by a blower
3 O 56. The air carries the particles along the channel 52 to an outlet 64.
The

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channel 52 has a curved section 58 having a fine screen 60 around its
outside periphery.
[0018] As very fine particles of starch pass the fine screen 60 they
are expelled through the fine screen 60, where they can be collected at a
separate outlet 62. The fine screen 60 may have apertures on the order of
1/8 of an inch in size, for example. The very fine particles which escape
through the fine screen 60 may be used for specialty snow products as they
will have a texture and appearance somewhat different from the coarser
1 O particles which pass by the fine screen 60 to the main outlet 64.
[0019] At the main outlet 64, the fragments of starch, which are now
in a form suitable for use as artificial snow, are delivered to a packaging
station 36 by a suitable conveyer, such as an auger, or the like. At the
packaging station the artificial snow is packaged, either into boxes or other
bulk storage containers to provide bulk artificial snow 38, or put into bags
to provide packaged artificial snow 39 for the retail trade. Bagging may be
performed by a suitable automatic bagging machine.
[0020] Because fine particles of artificial snow will tend to cling to
surfaces that acquire static electrical charges, it is desirable to avoid the
presence of any surfaces that can acquire a static electric charge. The
conveyors and other apparatus in production line 10 are preferably made of
metal, wood, or other materials that do not tend to acquire static charges.
2 5 Metal components are preferably grounded.
[0021] Further, it is desirable to package artificial snow in suitable
non-static bags. One type of bag suitable for packaging artificial snow is
shown in Figure 3. Bag 70 is a laminated bag having an outer layer 71 of
3 O protective polypropylene, an inner layer 72 of polyethylene, and an anti-

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static layer 73 which is electrically conductive and dissipates any static
charges which might otherwise attempt to collect on the bag.
[0022] While a number of exemplary aspects and embodiments have
S been discussed above, those of skill in the art will recognize certain
modifications, permutations, additions and sub-combinations thereof. It is
therefore intended that all such modifications, permutations, additions and
sub-combinations be considered to be part of this invention.

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