Patent Application
20110241247
In recent years, there has been an increasing consumer demand for aesthetically-unique soap bars. To make the soap bar more attractive, translucent, transparent, and different bar shapes, as well as multiphase and/or multicolored soap bars made from different soap materials and/or different colors, have been created to enhance the attractiveness and consumer appeal of these products.
For example, methods and extrusion apparatus to create striated soap bars have been shown in U.S. Pat. Nos. 3,891,365 and 3,947,200 (both Fischer) and 6,852,260B2 (Vu et al) and to create variegated, multicolored and/or marbled soap bars have been described in U.S. Pat. Nos. 3,823,215 and 3,940,220 (both D'Arcangeli), 3,993,722 (Borcher et al), 4,011,170 (Pickin et al), 6,727,211B1(Aronson et al), and 6,805,820B1 (Myers). An injection molding process using two different components to produce detergent bars comprising distinct zones has been described in U.S. Pat. No. 6,878,319B2 (Browne et al).
The present invention provides an extrusion process for the production of a solid soap product comprising feeding a soap composition into an extruder having a housing with an inlet and an outlet and a screw impeller traversing the extruder, wherein at least a portion of the housing from the inlet to the outlet of the housing, and ending at the outlet, is tapered to form a portion of the housing with a reduced cross-sectional area, and the screw impeller extends at least partly into the tapered portion of the extruder, where the screw impeller ends, and extruding the soap composition through the extruder.
The present invention also provides a process for producing a multiphase bar soap, comprising: processing a stream comprising a primary soap phase in at least one refiner and then into a plodder, comprising a plodder housing, a feed hopper for receiving material to be extruded, an extruder, an outlet through which material that has been extruder exits and an extruder cone diminishing in cross-section toward and ending at that outlet, via the feed hopper, a screw impeller disposed in the extruder and extending at least partly into the extruder cone; introducing at least one secondary soap phase into the stream of the primary continuous soap phase in the feed hopper of the plodder; and extruding the stream including the primary soap phase and the at-least-one secondary soap phase through the extruder cone with the screw impeller within the extrusion region to produce a bar soap having embedded visually distinct phases.
Ranges are used throughout herein in place of describing each and every value that is within the range. Any value within the range may be selected for the parameter being defined. And all percentage used, unless indicated otherwise, are intended to be percentages by weight.
An extrusion apparatus and method have now been developed for formulating a multiphase soap bar, comprising a first phase and at least one additional phase, where the additional phase(s) may have similar, or slightly higher hardness compared to the hardness of the first phase. In particular, utilizing a tapered screw extending at least partly into the extruder cone (frustum) region for manufacturing a multiphase soap bar produces a better bar aesthetic with visually distinct phases and/or permits the formation of desirable marbleized patterns. The use of such a modified extruder screw design makes the manufacturing of the desired bar aesthetic much more feasible, since simple soap formulas may be used, and no special processes or complicated equipment is needed for making the soap phases, especially for making a harder second soap phase in order that the phases do not excessively deform/blend during extrusion.
Accordingly, an extrusion process is provided for the production of billets of multiphase bars of soap, these bars include a continuous primary soap phase and at least one secondary solid soap phase embedded therein. The process includes passing a stream of a primary continuous soap phase through a first stage of a soap finishing line that includes a refiner having one or more roll mills and a plodder. At least one secondary solid soap phase is introduced into the stream of the primary continuous soap phase via a feed hopper/vacuum chamber later in the plodder design in order to form a combined stream of the primary (continuous) and the secondary (discontinuous) soap phases. The stream having primary and secondary phases is extruded using a screw with a tapered section extending into the extruder cone (frustum) and the stream is formed into billets having embedded visually-distinct phases, which billets are subsequently cut and pressed into bars of soap. The tapered screw is extended sufficiently into the extruder cone to form an “effective” extrusion zone in order that the visually-distinct phases and/or the desirable marbleized patterns are observed in the finished bar. This effective extrusion zone is the region between the end of the tapered screw and the outlet of the extruder cone. In one embodiment, the inlet diameter:outlet diameter ratio is generally up to 3:1. In other embodiments, the ratio is 2.5:1 to 2:1 or 1.5:1 to 1:1. The inlet diameter is the diameter of the extruder cone at the terminus of the tapered screw within the extruder cone and the outlet diameter, measured at the outlet of the extruder cone (frustum), becomes the diameter of the extruded soap billet.
In certain aspects of the invention, the extruder cone optionally comprises an inner tapered cone. In another aspect of the invention, the extruder cone optionally comprises a smaller extension cone (frustum) attached to the outlet of the extruder cone through which the process stream passes. In yet other aspects, the effective extrusion region further comprises a spider device, which may be disposed at the terminus of the tapered screw within the extruder cone, or may be disposed between the outlet of the extruder cone and the beginning of the extension cone, if present.
As illustrated in
In
When multiphase bar soaps have been manufactured via typical extruders in soap-finishing line processes, this production has often involved complex processes for selecting and preparing appropriate soap compositions for each phase. For example, in order to maintain visually-distinct phases while extruding multiphase bar soaps, hardness of the respective phases is selected to facilitate incorporation or embedding of the second phase into the first phase, while not excessively blending, mixing, smearing, or stretching the second phase within the first phase, in order to achieve a desirable aesthetic. Thus, in conventional processes, when extruding bar soap, in which a second phase is embedded within a first phase, a second solid phase is often selected to have a significantly higher hardness as compared to the primary soap phase, while the secondary phase suitably withstands various physical forces associated with the plodding process in the soap plodder in order to maintain desirable visually-distinct phases.
The instant extruder design and extrusion process overcomes the shortcomings associated with standard soap extrusion processes for making a multiphase soap bar, such as those having a first solid phase and a discrete second solid phase dispersed therein (e.g., a translucent, opaque or other second phase). As used herein for convenience, a multiphase soap is referred to as having a first continuous phase and a second discrete, discontinuous phase dispersed therein, however, the present disclosure contemplates a plurality of phases in a solid soap composition. In certain aspects, there are at least two visually- or compositionally-distinct phases.
In accordance with the present disclosure, an extruder in the bar soap manufacturing process has a tapered screw extending into the extruder cone region, to form an “effective” extrusion zone which has shorter length and a relatively low ratio of cross-sectional inlet diameter to outlet diameter in that effective extrusion region, which eliminates the key smearing/stretching that conventionally occurs in the plodding process.
Processes are provided in accordance with the present teachings that form solid soaps by using a plodder and extrusion-supporting devices that enable a wider selection of soap material properties and compositions (e.g., phases) and provide an aesthetically-distinct and—pleasing multiphase bar soap. As noted above, an extrusion region is designed to be shorter and to have a lower ratio of cross-sectional areas of the inlet to the outlet, respectively, as compared to conventional designs.
In certain aspects, an extrusion process for the production of a solid bar of soap, comprising a continuous primary soap phase and at least one secondary solid soap phase embedded therein, is depicted in the soap-finishing line 10A in
At least one secondary solid soap phase is introduced via a second process stream to the first process stream (primary soap materials) via an inlet 40 in the chamber/connector 23A to form a combined stream of the primary and secondary soap phases. The second process stream may be a liquid or may be in solid form (chips, flakes, beads, chunks, particulates, and the like) as it is introduced in chamber/connector 23A. The physical form of the second process stream may be selected based upon the desired aesthetics in the multiphase solid bar soap. For example, the shape and size of solid secondary phases are selected such that they result in desired size, and ultimate visual effects/aesthetics in the bar soap, as appreciated by those of skill in the art. Furthermore, the process may vary from the apparatus shown in
In one embodiment, there is minimal mixing, stretching, and/or smearing of the secondary soap phase during the extrusion process. By minimal it is meant that two distinct phases can be viewed in the final soap product by an ordinary observer having 20/20 vision or corrected to 20/20 vision at a distance of 30 cm.
The screw impeller shaft 26A forces the mixture of the primary and secondary soap phases through an outlet in a extruder cone (frustum) end 44. As noted above, in various aspects, the stream is passed through a extruder cone having a tapered screw extending thereinto.
In certain aspects of the present disclosure, the second-stage screw is modified to have a tapered screw 26A or an attached tapered screw part at the end of 26A (not shown), which extends at least into a portion of the extruder cone, having an increasingly-reduced diameter. Thus, rather than having an extruder cone, such as 28 in
In accordance with various aspects of the present teachings, the modified second stage screw 26A shown in
In various aspects, a distance “d” defined by the inlet region 52 to the outlet 50 is minimized to be relatively short, as compared to conventional extrusion equipment. For example, in certain aspects, “d” is selected to be less than or equal to 200 mm, preferably less than or equal to 150 mm, optionally less than or equal to 80 mm. In certain aspects, “d” is 40 to 80 mm, in comparison to conventional extrusion equipment, where it is 450 mm to 650 mm. In this manner, multiphase soap bars made by a process using a plodder extrusion apparatus having an effective extrusion zone or convergence zone with a relatively low inlet diameter to outlet diameter ratio and/or reduced length between inlet and outlet, provide an extruded soap bar billet having an improved aesthetic and further enables the use of a wider variety of soap compositions and hardness properties for the respective phases.
With renewed reference to
In certain aspects, an extruder cone containing a tapered screw may further include an inner cone 28A installed within it toward the end of the extruder cone, which similarly provides an effective extrusion region with suitably low inlet diameter to outlet diameter ratio, such as shown in
In certain aspects, a extruder cone containing a tapered screw may further include an extension cone attachment, which similarly provides an effective extrusion region with suitably low inlet diameter to outlet diameter ratio, such as shown in
In certain other aspects, the dual-stage plodder is replaced with a single-stage plodder with tapered screw extending at least partly into the extruder cone. In another aspect, the dual-stage plodder may also be combined with other devices, such as an inner cone, an extension cone and/or a spider device.
In another embodiment, the tapered screw has at least one groove extending in a longitudinal direction within the extruder cone.
In another embodiment, the at-least-one secondary solid soap phase includes a translucent soap.
In another embodiment, the at-least-one secondary solid soap phase includes an opaque soap.
The multiphase soap billets and bars formed in accordance with the present teachings include a continuous phase and a discontinuous phase. Desirably, the moisture content of the second phase may be much higher when such a second phase is used in accordance with the extrusion processes of the present disclosure, as compared to such use in conventional multiphase soap extrusion processes. In one embodiment of the instant invention, the translucent soap chip has a typical moisture content of 16% to 18% as compared to a conventional multiphase soap extrusion process with ≦12% moisture. A second phase having a higher moisture content typically has a correspondingly-reduced hardness value. In another embodiment, a continuous phase and a discontinuous phase solid mass are combined in a solid multiphase soap bar, by adding together the materials for the respective phases in a mixer at a defined temperature range (35 to 55° C., or 38 to 45° C.), followed by extruding and molding to form the final billets.
The bar composition comprises 55 to 99% of the continuous phase, in another embodiment 75 to 95%, and in still another embodiment 80 to 90%.
The continuous phase includes a surfactant or detergent base suitable for cleansing the skin and optionally a plasticizing agent used to control its consistency.
The discontinuous phase may represent 1 to 35% of the bar in one embodiment, 5 to 25% in another embodiment, and 10 to 20% in yet another embodiment. It is generally the shape, distribution and surface quality (e.g., how visually distinctive) of the discontinuous phase that gives the bar a pleasing visual aesthetic, and in certain aspects, an artisan-crafted quality.
In certain aspects, the discontinuous phase domains of the solid multiphase soap bar may have a variety of shapes. For example, the domains may appear in cross-section to approximate oblate or prolate spheroids, disks, cylinders, prisms, rhomboids, cubes or crescents, or they may have irregular shapes. In certain aspects, such discontinuous phase domains have a longest dimension of 3 to 70 millimeters in length, in others 5 to 50, and in still others 5 to 35 millimeters. As discussed above, the discontinuous phase domain is optionally introduced via liquid injection of the discontinuous phases, which may create ribbons, stripes, marbling, and the like.
Further, either the continuous or discontinuous phase may be made multicolored, e.g., marbleized, through the judicious use of coloring agents/dyes, as is well known in the art.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/US2008/086566 | 12/12/2008 | WO | 00 | 6/10/2011 |
