US3294692A - Striped soap bars and method and apparatus for making the same - Google Patents

Description

Dec. 27, 1966 w. A. KELLY E AL 3,294,692

STRIPED SOAP BARS AND METHOD AND APPARATUS FOR MAKING THE SAME Original Filed April 10, 1961 '2 Sheets-Sheet 1 INVENTORS: WILLIAM A.KE.LLY

PHILIP J. PETIX THEIR ATTORNEYS Dec. 27, 1966 w. A, ELL ET AL STRIPED SOAP BARS AND MET HOD AND APPARATUS FOR MAKING THE SAME 2 Sheets-Sheet 2 Original Filed April L0, 1961 FIGB.

TH EIR ATTORNEYS United States Patent 3,294,692 STRIPED SOAP BARS AND METHOD AND APPA- RATUS FOR MAKING THE SAME Wiiliam A. Kelly, Teaneck, and Philip J. Petix, Lyndhurst, N .J., assignors to Lever Brothers Company, New York, N.Y., a corporation of Maine Griginal application Apr. 10, 1961, Ser. No. 161,906. Divided and this application Oct. 21, 1964, Ser. No.

5 Claims. or. 252-134 This is a division of copending application Serial No. 101,906, filed April 10, 1961, now abandoned.

This invention relates to the manufacture of soaps and detergents and it relates particularly to the manufacture of cakes of soap, detergent or the like having stripes of a different color, composition or both therein.

Many attempts have been made heretofore to produce soap cakes having ornamental designs, indicia or the like of a diiferent color therein but none of them has been commercially feasible.

Among the manufacturing techniques proposed heretofore are those involving the punching of a hole or series of holes in a bar of soap and then introducing preformed complemental inserts of a material of different color or kind into the punched hole or holes.

Other processes involve the extrusion of a continuous rod or bar of soap, forming grooves or holes in and extending lengthwise of the bar and introducing into the hole or groove through a separate nozzle or nozzles a soap or other plastic material of a different color or com position.

The principal difficulty with inserting se arately-formed bodies into holes on soap cakes or of laminating together separately formed layers of soap is that they cannot be bonded together sufficiently strongly to prevent the resulting cake from delaminating and breaking up before it is consumed unless they are bonded together with special adhesives. Moreover, the cost of punching the holes, forming the insert bodies or layers and combining them is prohibitively expensive. When designs other than straight lines are put into continuously extruded rods it is necessary to extrude the rod from the plodder, face on, so that the grain structure is perpendicular to the face rather than parallel with the face of the stamped cake. The perpendicular orientation of the grain tends to cause severe face cracking during use of the cake. In addition, separation of any design that might be inserted can easily occur if any distortion of the cake takes place during stamping. More-over, with this type of extrusion, if cakes having rounded faces are desired, the design will be distorted during stamping. To avoid distortion of design, the bars must be shaved to a rounded face curvature before stamping to avoid substantial flow of soap during stamping. Shaving of the cakes causes considerable scrap to be formed tending to make the process uneconomical.

Methods involving the simultaneous extrusion of materials to form a composite, continuously extruded bar of soap have been unsatisfactory for the reason that the proportions of the extruded materials vary unpredictably, due to the different pressure on and the different plasticities of the materials. As a result, the pattern or shape of the inserted material will vary widely and unpredictably producing a cake of undesirable appearance.

In accordance with the present invention a striped cake of soap, a soap-non-soap, a non-soap detergent or the like is provided in which one or more stripes of uniform width and appearance extend through the soap to an extent enabling the striped appearance of the cake to be.

maintained until it is consumed. The relation of the stripe or stripes to the cake is such that the cake will not break or not delaminate as the cake is being used. Moreover, in accordance with the invention, the stripe or 3,294,692 Patented Dec. 27, 1966 stripes can be of different colors, composition or both than the material forming the body of the cake. Thus, for example, the material forming the stripe or stripes may contain germicides or the like which are normally incompatible with soap, or discolor soap, or produce obnoxious odors or lose their germicidal properties when mixed with soap. By adding the germicide to a compatible material and, using it to form the stripe or stripes in the cake the germicidal properties of the resulting cakes are enhanced and the difliculties mentioned are overcome. Also, it is possible to add superfats, cosmetic creams or the like to toilet soap cakes. When these ingredients are incorporated into toilet soaps, they soften the soap, making it diflicult to process and finish into a satisfactory commercial product. However, by incorporating such creams or superfats in the form of one or more stripes in a cake, the advantages thereof are retained and the soap making up the cake can be processed in a normal manner. Therefore, in accordance with the invention, unusual properties can be imparted to cakes of soap and detergents in addition to improving their esthetic appeal.

In the production of commercially satisfactory striped soap, soap-non-soap detergent cakes it is necessary to arrange the stripes in the cake in such a manner that they will be visible while the cake is in use and until it is almost completely consumed. As pointed out above, separately formed decorative inserts cannot be bonded to the cakes strongly enough to prevent delatmination and breakage of the cakes without special adhesives. Accordingly, in a satisfactory product, the stripes must be arranged so that they will not interrupt the continuity of or excessively weaken the cake even when it is almost completely used up. To that end, and in accordance with the present invention, the stripes in one side of the cake extend.

only to about the midplane of the cake while the stripes in the opposite side of the cake also extend inwardly to about the midplane of the cake and are offset laterally from the stripes extending from the opposite side in an amount of at least about /3 of an inch. Inasmuch as the stripes extend half way through the cake the stripes will be present until the cake is completely used. By offsetting the stripes from the opposite sides with respect to each other, a strong skeleton or core structure is provided which is capable of withstanding substantial stress without breaking or delaminating along the boundaries of the stripes. It is not necessary that stripes extend from both faces of the bar towards the middle since under normal use conditions it is expected that both faces of the bar will wear down about equally. It is possible to have the stripes extending from one face only to a point near the:

center of the bar in which case the stripes would appear on the surface of one face of the bar until the bar was consumed. This arrangement also provides a strong supporting skeleton for the stripes.

It will be understood that substantially all soaps, soapnon-soaps and non-soap detergents which are made into' reference may be had to the accompanying drawing in which:

FIGURE 1 is a plan view of a typical soap cake embodying the present invention;

FIGURE 2 is an end view of the soap cake;

FIGURE 3 is a schematic perspective and partial sectional view of a die for making striped soap in accordance with the present invention shown in FIGURE 1; and

FIGURE 4 is a view in cross-section taken on line 4-4 of FIGURE 3.

For convenience, in the description of the invention hereinafter, reference is made especially to soap bars. It will be understood, however, that the present invention is concerned generally with the manufacture of bars of water-soluble cleansing compounds consisting essentlally of members of the group consisting of soaps, non-soap synthetic detergents and mixtures thereof, the member being of such a consistency that it may be extruded through an orifice and thereafter formed and hardened into a self-sustaining cake.

As shown in FIGURE 1, a typical cake of soap embodying the present invention is of generally rectangular cross-section and generally rectangular shape in plan. It may have rounded corners and edges, if desired. It will be understood that the cake may be of almost any desired shape which can be formed by molding from sections of an elongated rod, as described hereinafter.

Extending inwardly from one face 11 of the cake are a pair of stripes 12 and 13 composed of a colored soap, as defined above, or any other material, such as a superfat, a cosmetic cream, an inert material, colored or not, containing a germicide or the like, referred to hereinafter generically as a different soap material. The stripes 12 and 13 are in spaced-apart, parallel relation and have inner edges disposed substantially in the midplane of the soap cake.

Extending from the opposite surface 14 of the cake are a pair of stripes 15 and 16 which may be formed of the same material as the stripes 12 and 13 or a different material, e.g., of the same or different color, composition or both. It will be understood that more or fewer than two stripes 12 and 13, 15 and 16 may be provided or a single stripe or a plurality of stripes may extend from one side only, of the cakes, if desired. The inner edges of the stripes 15 and 16 terminate at about the midplane of the cake of soap and do not overlap the inner edges of the stripes 12 and 13 appreciably. A slight amount of overlap is permissible for the reason that when the cake is worn down sufficiently to disintegrate, it will be so thin or small as to be of little further use. Moreover, the stripes 15 and 16 are offset from the stripes 12 and 13 at least about A; of an inch so as to provide a layer or core of substantial thickness and strength between the stripes, thereby to strengthen the resulting cake and prevent its disintegration. As pointed out above, it is diflicult to cause the striping material, even if it is the same, except for color, as the remainder of the cake, to cohere or bond to the cake and planes of weakness unavoidably are present which would permit the soap cake to break apart, unless the cake is continuous between and around the stripes.

It is also necessary, in order to provide a commerciably satisfactory bar, to form the stripes in the soap cake economically and also to insure that the stripes will be of uniform width and thickness. To that end, novel apparatus is provided which satisfies the requirements set forth above.

FIGURES 3 and 4 disclose schematically a die member 20 composed of a pair of upper and lower plates 21 and 22 having spacer members 23 and 20 between their lateral edges to provide a die passage 25 through which soap is forced to form a continuous elongated rod. Plastic soap is supplied to one end of the die passage 25 by means of a screw conveying device such as a screw type soap plodder 26 which forces the. soap under pressure through .the die passage 25. The upper plate 21 is provided with a transverse blind bore 27 which is connected with a screw conveying device such as the screw type plodder 28 and also carries a pair of flanges 29 and 30 which extend downwardly into the die passage 25 to its midplane. Each of the flanges 29 and 30 has a closed or solid leading edge portion facing upstream with respect to the flow of soap at the inlet end of the die passage 25 and a slotted trailing edge spaced inwardly from the discharge end of the passage and facing downstream. The slots 31 and 32 extend the full height of the flanges 29 and 30 respectively, into communication with the bore 27 and are open at the bottom and trailing edges of the flanges. Similarly the lower plate 22 is provided with a blind bore 33 which communicates with a screw conveying device such as the screw type plodder 34. If the material supplied to the bores 27 and 33 is the same, they may beconnected to a single plodder. Flanges 35 and 36 similar to the flanges 29 and 30 and having slots 37 and 38 therein communicating with the bore 33 extend upwardly into the passage 25 and have their upper ends in about the same plane as the lower ends of the flanges 29 and 30, i.e., in about the midplane of the die passage 25.

In operation, plodder 26 supplies plastic soap to the die passage and the soap flows through the passage 25 and is discharged therefrom in the form of an essentially continuous rod of uniform cross-section. As the soap flows around the flanges 29, 30, 35 and 36, they form grooves of uniform depth and width in the soap rod. Simultaneously different soap material is forced into the bores 27 and 33 by means of the plodders 28 and 34 and flows through the slots 31 and 32, 37 and 38 into the grooves in the advancing rod of soap. The material supplied by the plodder 28 may be the same as, or different from, the material supplied by the plodder'34. Inasmuch as the slots 31, 32, 37 and 38 extend from the bottom to the tops of the flanges the different soap material completely fills the grooves. The die passage 25 extends beyond the trailing edges of the flanges 29 and 30, 35 and 36 to form'a compacting zone. The spacers 23 and 24, the plates 21 and 22 or both may be slightly tapered in the compacing zone downstream of the flanges to form a constriction in the compacting zone.

We have discovered that the use of screw conveying devices such as the screw type plodders 26, 28 and 34 in combination with a constricted compacting zone in the die simplifies greatly the production of uniform, stronglybonded stripes in the extruded soap rod. With such plodders, it is unnecessary to provide flow control or proportional feeding means to assure the formation of uniform stripes in the soap rod and it is not even necessary to control closely the plasticity of the extruded soap and different soap material. Screw conveying devices such as the plodders described above, are not positive feeding devices. When a certain back pressure develop-s in a screw type plodder by virtue of friction or the presence of a constriction, slippage or churning takes place therein so that the material is supplied by the plodder at a substantially uniform pressure. The pressure-responsive action of the screw plodders illustrated in the drawings, therefore, maintains a uniform and closely-related feed rate of the soap and the different soap material to form and completely fill the grooves in the rod and to bond the stripes to the rod. It will be understood that the plodders 26, 28 and 34- may be provided with variable speed drives to establish an equilibrium condition between rates of extrusion of the rod and the stripes to assure filling the grooves with the striping material. After the equilibrium condition is attained, the extrusion of the rod and stripes tends to be self-regulating so that only minor changes in the striping screw speed over a considerable time period are required to maintain the width of the stripes. The use of Vacuum plodders for both the stripes and the main body improves the bonding of the stripes in the rod by excluding air from the soap thus avoiding entrainment of air between the stripe and the main body of the rod.

As the striped soap rod issues from the die passage 25, it may be received on a conveyor (not shown) and carried to a cutter whereit is cut into cakes of a desired size and molded or shaped to form cakes like that shown in FIGURES 1 and 2, or of any other desired shape.

Alternatively, the rod can be cut into cakes as it leaves the passage 25 and the sections carried to a molding apparatus for molding into cakes. In the illustrative cake, the stripes extend lengthwise but it will be understood that the cake can be provided with transverse stripes by suitably cutting sections from the soap rod and molding them.

The die is shown sche-matically in FIGURES 3 and 4. In production apparatus, the die may take other forms and may be constructed in other ways. For example, the die may be a unitary casting having suitable couplings for connecting the bores and passage therein to the plodders and the bores 27 and 33 may extend lengthwise in parallel or substantially parallel relation to the plodder 26.

Other changes may be made in-the apparatus as may be required for producing soap cakes of various sizes, for varying the number and size of the stripes to be formed in the cake and the orientation of the stripe or stripes with respect to the cake. The apparatus illustrated renders the grain of the soap and the grain of the stripes substantially parallel thereby improving the ad hesi-on and bonding of the stripes to the soap.

The following examples illustrate the production of typical striped products embodying the invention.

Example 1 A white sodium soap comprised of a base stock of 80% tallow, 20% coconut oil and containing about 15% moisture was milled and worked prior to extrusion in a typical manner and used for the main body of the striped rod. Soap having the same moisture content and to which was added germicide, 3,4',5-tri-bromosalicylanilide and a pink dye was worked in a similar manner. The white soap was extruded through a die like that shown in FIGURES 3 and 4 except that a single injecting flange on one side and a double flange on the other were used. A single plodder was used to inject the colored soap into the grooves on both sides of this rod. The extruder for the main body was started first and then the extruder for the striping insert was started. The speed of the striping plodder was adjusted to fill the grooves completely. Once this adjustment was made, a continuous rod of striped soap came out the end of the extrusion die with no appreciable variation in the appearance of the stripes. The rod was cut into blanks and the blanks stamped into finished cakes on a typical soap-stamping press. The stripes accounted for approximately by weight of the cake.

The cakes were tested for germicidal activity and were equivalent to cakes in which the same total quantity of germicide was added to the entire cake.

Similar all-soap cakes containing no germicide, but with different colored stripes were made. These included stripes of different width on each face of the cake, and different numbers of stripes, up to eight total stripes, four on each side. Cakes were also made in which the main body was colored and the stripes were white.

Example 2 Cakes were made using the method described above in which the main body of the cake was soap and the stripes were composed of a soap-non-soa-p mixture containing 18% tallow Igepon T (a fatty acid amide sulphonate, e.g. a sodium tallow fatty acid methyl taurate), 6% free stearic acid, about 6% water and the balance tallow and coconut soaps.

Other cakes were made in which both the main body and the stripes were composed of a soap-non-soap having the same composition as that described above, the stripes being differentiated by color.

Example 3 Cakes were made, as above, in which both the main body and the stripes were composed of a detergent type material as described in Patent No. 2,894,912. This material contains about 50% coconut Igepon A (a fatty acid ester sulphonate, e.g. an ester of sodium isethionate and coconut oil fatty acids), 9% soap, 27% stearic acid, 2% sodium dodecylbenzene sulphonate, 4% Water and 8% miscellaneous salts.

Inasmuch as the apparatus and the resulting product are susceptible to considerable variation as indicated above, the forms of the invention disclosed herein should be considered as illustrative and not as limiting the scope of the following claims.

We claim:

1. A cleansing bar comprising an extruded matrix of a first water-soluble cleansing compound in the shape of a bar having a pair of principal faces on opposite sides thereof and opposed grooves along said principal faces parallel to each other and to the grain of extrusion, said grooves extending into said matrix and terminating about the midplane thereof, each of said grooves being offset from the nearest opposed groove by at least about A; inch, and a second water-soluble cleansing compound in each of said grooves, said second compound being extruded therein concurrently with the extrusion of said matrix, said cleansing bar thereby having stripes extending into said bar in substantially parallel relationship to each other and to the grain of said cake, said first and second water-soluble cleansing com-pounds each consisting essentially of at least one member of the group consisting of soaps, non-soap synthetic detergents and mixtures thereof, said compounds being of such a consistency that they may be extruded through an orifice and thereafter formed and hardened into a self-sustaining cake.

2. The soap product set forth in claim 1 in which said stripes have a color different from that of said soap cake.

3. The soap product set forth in claim 1 in which said stripes have a composition different from that of said soap cake.

4. The soap product set forth in claim 1 in which at least one of said stripes has a different color than do the other stripes.

5. The soap product set forth in claim 1 in which said stripes extend lengthwise of said cake.

References Cited by the Examiner UNITED STATES PATENTS 1,828,361 10/1931 Crary et al. 252-134 2,296,842 9/1942 Garvey et a1 252-134 2,423,435 7/1947 Block 252-134 2,613,185 10/1952 Marshall 252-92 2,894,912 7/1959 Geitz 252-121 3,043,778 7/ 1962 Kelly 252-107 FOREIGN PATENTS 469,622 12/ 1928 Germany.

2,831 1902 Great Britain.

SAMUEL H. BLECH, Primary Examiner.

ALBERT T. MEYERS, JULIUS GREENWALD,

Examiners.

Claims (1)

1. A CLEANING BAR COMPRISING AN EXTRUDED MATRIX OF A FIRST WATER-SOLUBLE CLEANSING COMPOUND IN THE SHAPE OF A BAR HAVING A PAIR OF PRINCIPAL FACES ON OPPOSITE SIDES THEREOF AND OPPOSED GROOVES ALONG SAID PRINCIPAL FACES PARALLEL TO EACH OTHER AND TO THE GRAIN OF EXTRUSION, SAID GROOVES EXTENDING INTO SAID MATRIX AND TERMINATING ABOUT THE MIDPLANE THEREOF, EACH OF SAID GROOVES BEING OFFSET FROM THE NEAREST OPPOSED GROOVE BY AT LEAST ABOUT 1/8 INCH, AND A SECOND WATER-SOLUBLE CLEANSING COMPOUND IN EACH OF SAID GROOVES, SAID SECOND COMPOUND BEING EXTRUDED THEREIN CONCURRENTLY WITH THE EXTRUSION OF SAID MATRIX, SAID CLEANSING BAR THEREBY HAVING STRIPES EXTENDING INTO SAID BAR IN SUBSTANTIALLY PARALLEL RELATIONSHIP TO

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