FIELD OF THE INVENTION
[0001] This invention relates to bag, especially for use in storing particulate products
such as, but not limited to, detergent, pet food, coffee, cereal etc., wherein the
bag comprises thin, shaped particles.
BACKGROUND OF THE INVENTION
[0002] For many years aesthetic particles have been incorporated into products for improving
the aesthetics of the product. Traditionally, these aesthetic particles are coloured
particles for example as described in
WO 97/33965. They may also be in the form of noodles as described in
US 6,747,000. Aesthetic particles may also be introduced in particulate products, such as detergent
composition, as a signal for the consumer that a specific technical benefit is to
be expected with the product.
[0003] As new products are marketed there is a need for new visual signals to distinguish
them from other products. The consumer is also seeking for new compositions having
an attractive appearance. Accordingly, there is always a need for new aesthetics particles
to be introduced in particulate products.
[0004] Thin, shaped particles are especially suitable for those purposes. However, such
particles tends to be fragile due to their thinness and may break during shipping
and handling at the store.
[0005] Accordingly, there is a need to provide products comprising thin, shaped particles
which can better sustain shipment and storage conditions.
SUMMARY OF THE INVENTION
[0006] The inventors have discovered that the above mentioned problem can be alleviated
with the use of bags comprising a material having a 2% secant tensile modulus of at
least 100 MPa as measured according to ASTM D882 and a thickness of at least 30 microns.
[0007] Accordingly, the present invention meets the aforementioned needs by providing a
bag comprising a material having a 2% secant tensile modulus of at least 100 MPa as
measured according to ASTM D882 and a thickness of at least 30 microns and containing
a composition comprising:
- thin, shaped particles having a main length, a, of at least 1.5 mm,
- base granules having an average geometric mean particle diameter, of at most 0.8*a
mm (80% of the main length of the thin, shaped particle), or even at most 0.6*a mm,
or even 0.4*a mm.
[0008] The thin, shaped particles to base granules weight ratio may be less than 0.1, or
even less than 0.01.
[0009] According to one of its aspect, the invention relates to a composition comprising:
- thin, shaped particles having a main length, a, of at least 1.5 mm,
- base granules having an average geometric mean particle diameter, of at most 0.8*a
mm (80% of the main length of the thin, shaped particle),
wherein the weight ratio of thin, shaped particles to base granules is of less than
0.1, or even less than 0.01.
[0010] The composition may be comprised in a bag, especially a bag comprising a material
having a 2% secant tensile modulus of at least 100 MPa as measured according to ASTM
D882 and a thickness of at least 30 microns.
[0011] The thin shaped particles may be concave and/or the base granules may be substantially
convex.
[0012] Without wishing to be bound by theory, it seems that the smaller base granules tend
to surround and support the thin, shaped particles resulting, in the specific ratio
of the invention, of a better protection of the concave, thin, shaped particles.
DETAILED DESCRIPTION OF THE INVENTION
Thin, shaped particles
[0013] Thin, shaped particles may be understood as 3 dimensional particles having a first
dimension x, a second dimension y and a third dimension z in the Cartesian planes
and the maximum dimension in the second and third planes is at least 3 times the dimension
in the first plane.
[0014] The thin, shaped particles have a main length, a, of at least 2 mm or even at least
3 mm. The main length, a, is to be understood as the longest length.
[0015] The thin, shaped particles to base granules weight ratio may be less than 0.1, or
even less than 0.01.
[0016] The thin, shaped particle may be shaped like any letter of the alphabet, stars, triangles,
squares, pentagons, hexagons, heptagons, octagons, non-geometric shapes including
for example shapes of animals, birds or other living things, cartoons, flowers, moons,
discs, crosses and any other desired shape as disclosed in
WO 2006/079416 or
GB 2 358 403.
[0017] The thin, shaped particles may be concave. A concave particle is a geometric solid
in which at least 50% of the pairs of points lying on or within the surface of the
solid cannot be connected by a straight line which is totally contained within the
solid or surface thereof. Familiar examples of concave particles are particles having
a ring or horseshoe shape as well as thin curved particles. Concave particles may
be even more fragile.
[0018] The thin, shaped particles may be of any suitable material. The particles may comprise
a material selected from gum Arabic, hydroxypropylmethylcellulose, sodium casinate,
and soap. In particular, the particles comprise from 60% to 99% by weight of soaps
of C
8-C
20 fatty acids. Typically the particles comprise from 0.1 % to 20% by weight of water.
Preferred particles also comprise an inorganic salt, for example from 0.05% to 5%
by weight of an inorganic salt, preferably sodium chloride. Preferred particles also
comprise glycerine, typically from 0.01 % to 10% by weight of glycerine. Such soap-containing
particles will typically comprise less than 5% by weight of free fatty acids. Such
particles have been found to provide highly satisfactory shaped particles, for example
providing an excellent balance between low deformability during cutting, good dissolution
and frangibility. The presence of glycerine in the particles may be particularly advantageous
as it may also improve the colouring of the particles if a colorant is incorporated.
[0019] The thin, shaped particles may further comprise any adjunct ingredient as stated
below.
[0020] The thin, shaped particles are preferably coloured.
[0021] When used herein the term "cutting direction" refers to the direction in which the
blade moves through the first article while forming the thin, shaped particle. The
"cutting plane" refers to the plane parallel to the cutting direction. The "length
of the thin, shaped particle" refers to the length of the thin, shaped particle in
the direction normal to the cutting plane and, when extruded, preferably the length
of material extruded before the cutting step. When used herein the term "cross-section"
refers to the shape of the face of either the shaped or first articles (as referred
to) which is parallel to the cutting plane. First article describes any body of material
from which a further thin, shaped particle may be cut.
[0022] The method according to the invention for forming the thin, shaped particles of the
present invention may be a batch or a continuous process, continuous processes are
preferred as a higher production rate can be achieved.
[0023] The first article of the present invention may typically be formed by extrusion.
Typically, extrusion is understood to mean any process by which a body of material
is forced through a die or orifice so as to form a length of extruded material. In
the case of the present invention the extrusion will normally be performed using a
commercially available extruder, such as a screw extruder. Commercially available
screw extruders typically comprise one or more feeders or hoppers, for storing the
material prior to extrusion; a barrel which houses one or more screws; and a die through
which the material is extruded. The screws are rotated and the material is typically
heated and/or kneaded and/or compacted as it is drawn through the barrel. Typically,
the material is forced through the one or more dies, which are usually situated at
the end of the barrel furthest from the one or more feeders. It is preferable to use
more than one die as this increases the number of first articles, and thus thin, shaped
particles, which can be produced at any one time. In a preferred embodiment of the
present invention the extruder die comprises greater than or equal to 50 orifices,
preferably greater than or equal to 100 orifices and even more preferably greater
than or equal to 200 orifices. The shape of the one or more dies' orifices' will determine
the cross-section and/or shape of articles extruded therefrom. The screw configuration
is typically chosen depending on how deformable the material is and at what temperature
the material is mobile enough to be properly compacted and extruded. In certain embodiments
of the present invention the temperature of the extrudate may typically be from 70°C
to 130°C, or from 80°C to 120°C or even from 90°C to 110°C. Screw configurations can
be chosen with varying amounts of back-flow, sheer, compaction, heat and combinations
thereof. Commercially available screw extruders suitable for use in the present invention
include but are not limited to the TX-85 Twin Screw Extruder manufactured by Wenger.
[0024] When extrusion is used to form the first article, it is preferable for the thin,
shaped particle to be cut from the first article as it is extruded. This is understood
to mean that as the material leaves the die it is cut immediately to form the thin,
shaped particle, as opposed to lengths of material being formed which are then stored
and cut at a later time. Typically, the first article (the extrudate) will be cut
when the length of extrudate equal to the desired length of the thin, shaped particle
has been extruded.
[0025] Typically the thin, shaped particle will be cut from the first article by running
the blade flush to the die. Preferably the blade will be tension mounted against the
die's surface so as to ensure it runs as closely over the face of the die as possible.
It is of course understood that in other embodiments of the invention, the material
may be formed into extended lengths of material and cut at a later time.
[0026] The thin, shaped particle may have any preferred cross-section. Particularly preferred
thin, shaped particle cross-sections are annular, other preferred cross-sections include
any letter of the alphabet, stars, triangles, squares, pentagons, hexagons, heptagons,
octagons, non-geometric shapes including for example shapes of animals, birds or other
living things, cartoons, flowers, moons, discs, crosses and any other desired shape.
In certain embodiments the thin, shaped particle may of course be non-annular. In
a preferred embodiment of the present invention the thin, shaped particle will have
an extruded length (i.e. the length of the thin, shaped particle) of from 0.05 mm
to 1 mm, preferably from 0.1 mm to 0.75 mm and most preferably from 0.2 mm to 0.5
mm. In certain embodiments, the length of the thin, shaped particle will generally
be equal to the length of material extruded prior to the cutting step taking place.
[0027] In the preferred embodiments of the present invention where the first article is
formed by extrusion it is preferable for the orifice of the die to be shaped such
that is compensates for the deformation during the cutting step so as to achieve a
thin, shaped particle with a desired cross-section.
[0028] As discussed above, in a preferred embodiment of the present invention the first
article's cross-section is greater, with respect to the desired cross-section of the
thin, shaped particle, in the cutting direction. In the embodiments of the present
invention where the first article is formed by extrusion it is preferable that the
orifice through which the composition is extruded is orientated such that the orifice's
greatest cross-section is substantially parallel to the cutting direction.
[0029] In a further embodiment of the present invention the ratio between the smallest length
of the thin, shaped particle to its main length is from about 1:3 to about 1:100,
or even from about 1:5 to about 1:50, or even from about 1:10 to about 1:20. When
the particles are extruded, the main length is usually the greatest cross-section
and the smallest length is usually the extruded length.
[0030] The shape of the die's orifice will depend upon the shape of the desired thin, shaped
particle, and the compensation for deformation or cutting. In one embodiment of the
present invention the ratio of the diameter of the first article's cross-section in
the cutting direction to the diameter of thin, shaped particle's cross-section in
the cutting direction is greater than 1. Preferably the ratio will be from 5:1 to
101:100 or even from 3:1 to 11:10 or even from 1.5:1 to 1.05:1.
[0031] In a particularly preferred embodiment the desired thin, shaped particle comprises
a circular ring and an elliptical ring orifice is used to form an elliptical tube-shaped
first article from which substantially circular ring-thin, shaped particles are cut.
In a particularly preferred embodiment of the present invention a die having at least
one elliptical orifice is used. Preferably said elliptical orifice will have a greatest
diameter of from 2 mm to 8 mm, preferably from 3 mm to 7 mm, and a smallest diameter
of from 1 mm and 5 mm, preferably from 2 mm and 4 mm. In a particularly preferred
embodiment the elliptical orifice will have an elliptical central pin inserted within
the orifice so as to form an elliptical annular orifice. Preferably, said elliptical
central pin will have a greatest diameter of from 0.5 mm to 7.5 mm, preferably from
2.5 mm to 5 mm, and a smallest diameter of from 0.25 mm to 3.5 mm, preferably from
0.5 to 2 mm. The particular shape of the die orifice required to achieve the desired
thin, shaped particle will depend on a number of factors including the extrudate composition,
the extrudate viscosity, the cutting speed and the length of the thin, shaped particles.
[0032] When used herein the term blade will be understood to have its normal meaning in
the art and will include any means which may be used to cut, cleave or generally remove
a thin, shaped particle from a first article; typically, including a knife. Particularly
preferred blades for use herein are those mounted on rotary cutters. Rotary cutters
comprise a number of individual blades fixed to a device having an axel. The device
is rotated about the axel, with the blades aligned such that they are at a generally
normal angle to the direction of rotation. Thus, a number of blades can be made to
pass over a single location in a short period of time; allowing a great number of
thin, shaped particles to be cut from first articles in quick succession. Typically,
when rotary cutters are used in the present invention they may comprise more than
one blade, preferably more than or equal to five blades, more preferably more than
or equal to ten blades and most preferably more than or equal to fifteen blades. Typically
the rotary cutters will be rotated at greater than or equal to 1000 revolutions per
minute (rpm), preferably greater than or equal to 2000 rpm and even more preferably
greater than or equal to 3000 rpm. In a particularly preferred embodiment of the present
invention the rotary cutter may be located directly adjacent to the die of the extruder,
where it will cut the thin, shaped particles from the first articles as they are extruded.
Preferably the rotary cutter is located such that the blades are flush to the extruder
die and even more preferably they are tension mounted against the die. Particularly
preferred rotary cutters and blades are commercially available such as those from
Wenger or de Souza.
[0033] In a preferred embodiment of the present invention the angle of the blade with respect
to the cutting plane will be less than or equal to 45°, or even less than or equal
to 25°, or even more less than or equal to 15°. By using lower blade angles it has
been found that the thin, shaped particle it deformed less during the cutting step.
[0034] In a preferred embodiment of the present invention the one or more blades may be
held by blade holders. Particularly preferred blade holders are tapered blade holders.
A tapered blade holder is understood to mean any blade holder which is designed such
that it will not deform the thin, shaped particle once the thin, shaped particle has
been cut from the first article. Preferred tapered blade holders for use herein will
cover a portion of the blade and will not form an abrupt edge with the uncovered portion
of the blade. Particularly, preferred tapered blade holders will have an upper surface
which intercepts the upper surface of the blade at an angle of less than 90°, preferably
less than 45°, even more preferably less than 30° and most preferably less than 20°.
The tapered blade holder may have a concave curved upper surface, such that the angle
of the blade holder surface to the blade increases exponentially as the distance from
the blade tip increases.
[0035] Typically, the thin, shaped particle and the first article will comprise substantially
the same composition.
[0036] The bag may comprise from 0.01 % 10% of thin, shaped particles, for example from
0.01 % to 5%, or even from 0.1 to 2%, for example from 0.2 to 1%, by weight of thin,
shaped particles.
The base granules
[0037] The base granules may be a detergent composition and may comprise a surfactant. The
base granules may further comprise any adjunct ingredient as stated below.
[0038] The base granules may be made by any particulation or granulation process. An example
of such a process is spray drying (in a co-current or counter current spray drying
tower) which typically gives low bulk densities of 600g/l or lower. Particulate materials
of higher bulk density can be prepared by a continuous granulation and densification
process (e.g. using Lodige® CB and/or Lodige® KM mixers). Other suitable processes
include fluid bed processes, compaction processes (e.g. roll compaction), extrusion
and spheronization, as well as any particulate material made by any chemical process
like flocculation, crystallisation sentering. The base granules may be composed by
from 20 to 100% for example from 50 to 90 %, or from 60 to 80% of spray-dryed powder
and from 0 to 80%, for example from 10 to 50% or even from 20 to 40% of added powder.
[0039] Granulation processes are well known in the detergent art. Some non-limiting examples
include the process as described in U.S Patent Nos.
5,489,392.
5,516,448 to Capeci et al. The granules may be substantially convex. A substantially convex
granule is a geometric solid in which at least 75%, in particular 85%, or even substantially
all pairs of points lying on or within the surface of the solid can be connected by
a straight line which is substantially contained within the solid or surface thereof.
Familiar examples of convex granules are extruded cylinders, balls and tablets. Of
course, it is intended for convex granules which contain minor irregularities to still
be considered convex particles.
[0040] The base granules of the invention may have an average circularity of at most 50,
for example at most 30, or at most 23, or at most 18. Also base granules may have
an average aspect ratios of at most 2, or at most 1.5, or at most 1.3, or at most
1.2. Shape can be measured in a number of different ways known to those of ordinary
skill in the art. One such method is using optical microscopy with Optimus (V5.0)
image analysis software. Important calculated parameters are "Circularity" which is
defined as (measured perimeter length of the particle image)
2/(measured area of the particle image). The circularity of a perfectly smooth sphere
(minimum circularity) is 12.57; and "Aspect Ratio" which is defined as the length/width
of the particle image.
[0041] The base granules may be processed or dry added. The base granules may have an average
geometric mean diameter of at most 1000 micrometers. Preferably, the geometric mean
particle diameter of the particles is from 400 microns to 900 microns, for example
from 500 microns to 800 microns, and in particular from 600 microns to 800 microns.
[0042] The base granules may be a composition as exemplified in
EP 1 776 442 which is incorporated by reference.
[0043] The bag may comprise from 50% to 99.9% of base granules, for example from 75% to
99.5%, or even from 90 to 99% by weight of base granules
[0044] The thin, shaped particles to base granules weight ratio may be less than 0.1, for
example from 0.001 to 0.05, in particular from 0.002 to 0.02, or even less than 0.01.
Adjunct ingredients
[0045] While not essential for the purposes of the present invention, the non-limiting list
of adjuncts illustrated hereinafter are suitable for use in the instant thin, shaped
particles and/or the base granules. They may be desirably incorporated in certain
embodiments of the invention, for example to assist or enhance cleaning performance,
for treatment of the substrate to be cleaned, or to modify the aesthetics of the cleaning
composition as is the case with perfumes, colorants, dyes or the like. The adjuncts
may be incorporated either as part of the thin, shaped particles or as part of a detergent
composition comprising the base granules. The precise nature of these additional adjunct
components, and levels of incorporation thereof, will depend on the physical form
of the particles or granules and the nature of the cleaning operation for which it
is to be used. Suitable adjunct materials include, but are not limited to, surfactants,
builders, chelating agents, dye transfer inhibiting agents, dispersants, additional
enzymes, and enzyme stabilizers, catalytic materials, bleach activators, hydrogen
peroxide, sources of hydrogen peroxide, preformed peracids, polymeric dispersing agents,
clay soil removal/anti-redeposition agents, brighteners, suds suppressors, dyes, perfumes,
structure elasticizing agents, fabric softeners, carriers, hydrotropes, processing
aids, solvents and/or pigments. In addition to the disclosure below, suitable examples
of such other adjuncts and levels of use are found in
U.S. Patent Nos. 5,576,282,
6,306,812 B1 and
6,326,348 B1 that are incorporated by reference.
The bag
[0046] The bag comprising a material having a 2% secant tensile modulus of at least 100
MPa and a thickness of at least 30 microns.
[0047] The 2% secant tensile modulus is measured according to ASTM D882 at 22°C. The bag
may comprise a material having a 2% secant tensile modulus of from 200 MPa to 2000
MPa, or even from 300 MPa to 1600 MPa, for example of at least 500 MPa.
[0048] The bags of the present invention may be formed from materials including but not
limited to polymeric film, woven materials, non-woven materials, preferably polyethylene
film, more preferably monolayers, coextrusions, two-layer laminations, three-layer
laminations and metalized laminations, all materials with or without lacquer coatings.
[0049] Bags according to the present invention can be formed by any method known in the
art. In particular, the bag may be provided via a process as disclosed in patent application
EP1409366.
[0051] The bag may have a thickness of from 30 microns to 200 microns, in particular of
from 60 microns to 170 microns or even of at least 100 microns, or even 120 microns
or 150 microns.
[0052] The bag may be such that from 0 to 10% of the inside space of the bag is distant
from the panel(s) of the bag by a distance inferior to the average by number main
length of the thin, shaped particles. In particular, the bag may be such that from
0.1 to 5%, or even less than 2%, for example less than 1 of the inside space of the
bag is distant from the panel(s) of the bag by a distance inferior to the average
by number main length of the thin, shaped particles.
[0053] The bag may have an opacity of more than 75%, for example of more than 80% or even
from 90% to 100%. When the thin, shaped particles are coloured, an opaque bag may
better prevent colour shift of the particles.
[0054] As used herein, the term "opacity" refers to the property of a substrate or printed
substrate which measures the capacity of the substrate to hide or obscure from view
an object placed behind the substrate relative to the point from which an observation
is made. Opacity can be reported as the ratio, in percent, of the diffuse reflectance
of a substrate backed by a black body having a reflectance of 0.5% to the diffuse
reflectance of the same substrate backed with a white body having an absolute reflectance
of 89%. Opacity can be measured as described in ASTM D 589-97, Standard Test Method
for Opacity of Paper (15°/Diffuse Illuminant A, 89% Reflectance Backing and Paper
Backing). A substrate high in opacity will not permit much, if any, light to pass
through the substrate. A substrate having low opacity will permit much, if not nearly
all, light to pass through the substrate. Opacity can range from 0 to 100%.
1. Bag comprising a material having a 2% secant tensile modulus of at least 100 MPa as
measured according to ASTM D882 and a thickness of at least 30 microns and containing
a composition comprising:
- thin, shaped particles having a main length, a, of at least 1.5 mm,
- base granules having an average geometric mean particle diameter, of at most 0.8*a
mm, or even at most 0.6*a mm, or even 0.4*a mm.
2. Bag according to claim 1, wherein the base granules comprises spray-dryed or agglomerated
granules.
3. Bag according to any one of the preceding claims wherein the base granules have an
average geometric mean diameter of at most 800 micrometers.
4. Bag according to claim 1 or 2, wherein the thin, shaped particles are concave and
in particular are discs or rings, preferably rings.
5. Bag according to any one of the preceding claims, wherein the thin, shaped particles
comprise soap.
6. Bag according to any one of the preceding claims wherein the thin, shaped particles
have a main length, a, of at least 2 mm or even at least 3 mm.
7. Bag according to any one of claims 2 to 7 wherein the thin, shaped particles to base
granules weight ratio is less than 0.1 or even less than 0.01.
8. Bag according to any one of the preceding claims, wherein the bag is comprising a
material has a 2% secant tensile modulus of at least 200 MPa, or even 300 MPa as measured
according to ASTM D882.
9. Bag according to any one of the preceding claims, wherein the bag comprises a material
having a thickness of at least 60 microns, in particular 100 microns.
10. Bag according to any one of the preceding claims wherein the shape of the bag is such
that less than 10% of the inside space of the bag is distant from the panel(s) of
the bag by a distance inferior to the average main length of the thin, shaped particles.