Patent Application
20090321299
Disclosed herein is a reusable wipes container having a relatively low density, and good effusivity. Specifically, there is disclosed a reusable low-density EVA foam wipes container that provides a cloth-like feel and improved consumer appeal.
Cleaning wipes are generally sold in plastic tubs, tubes or other containers, and a user typically extracts a wipe for use by pulling the wipe through an opening in the container. In most cases, the opening is covered by a lid, especially if the wipes are wet wipes. Typically, the plastic container or tub is sold pre-loaded with a supply of wipes. Once a consumer depletes the original supply of wipes, the user may discard the empty container and purchase a new pre-loaded container or tub. In some instances the container or tub may be reusable, and a user may simply purchase a new supply of wipes to refill the container or tub.
Typically, reusable/refillable wipes containers and disposable wipes tubes (i.e., tubs intended to be discarded after the pre-loaded supply of wipes are depleted) are made from the same or a similar material as the disposable wipes tubs. It is not uncommon for both disposable and reusable wipes containers to be made from a synthetic plastic material (e.g., injection molded polypropylene or low density polyethylene). The rigidity, hardness and/or other physical characteristics of a given container may vary depending on the material preference of the manufacturer, but at least some of the physical characteristics of the plastic containers tend to be perceived by consumers as being substantially the same. One such characteristic may be the commonly known property of effusivity, sometimes referred to as thermal inertia. Effusivity is generally considered by those of ordinary skill in the art to be how warm or cold an object feels to the touch. For example, a piece of cloth such as a cotton hand towel will typically feel warmer to the touch than a metal object such as a piece of steel even though both objects are the same temperature. It is believed that the cotton towel feels warmer due to its lower effusivity. Similarly, a plastic wipes container may feel colder than a cloth-like wipes container even though both containers have the same or substantially the same surface temperature. Due to the higher effusivity of plastic containers as compared to cloth-like containers, some consumers may find that commercially available wipes containers feel undesirably cold. It is believed that at least some consumers desire a container that feels relatively warm to the touch.
One solution to providing a wipes container with a soft, cloth-like texture and that feels relatively warm to the touch is to place a fabric outer cover on the outer surface of a traditional plastic wipes tub. In this way, the fabric outer cover may at least partially mask the characteristics of the relatively hard plastic. In one approach, the fabric may be laminated to the plastic container, for example, with an adhesive. Laminating a fabric outer cover to a plastic wipes container, however, may result in additional processing steps and/or materials, which typically translates to increased manufacturing complexity and costs. Another approach is to provide a removable/reusable cover that can be placed over a plastic wipes container; however, this may require the consumer to purchase an additional item, and may undesirably result in increased transactional costs to the consumer and/or the manufacturer. In addition to the disadvantages pointed out above, the fabric cover still may not sufficiently mask the undesirable characteristics of a plastic wipes container, and the consumer may not consider the wipes container to be cloth-like if the hard plastic characteristics of the wipes tub are the dominant features perceived by the consumer.
In another approach, a manufacturer of wipes containers may provide a wipes container formed entirely or primarily from a natural cloth material. Although using a natural cloth material such as cotton may help provide the desired cloth-like characteristics, fabrics such as cotton may have other undesirable characteristics such as high cost, high vapor permeability, and low structural stability.
Another problem that may be associated with reusable wipes containers is maintaining the wipes container in a clean and relatively pristine condition after repeated uses. Since a reusable wipes container may be used repeatedly, it is not uncommon for the wipes container to get dirty. In some instances, the wipes container may be used to store wipes for cleaning the skin of a baby. A caregiver of a baby or young child may find it undesirable to place a wipes container that appears dirty in the vicinity of the baby or young child. While a typical hard plastic wipes container may be cleaned with varying amounts of effort (depending on how dirty the container is and/or how clean a user wants it to be), at least some consumers of wipes and wipes products may find it undesirable to have to clean the wipes container by hand for a variety of reasons. Automatic cleaning machines such as dishwashers and washing machines might provide a means for a consumer to avoid manual washing of a reusable wipes container; however, at least some structural and/or functional features or elements of a typical hard plastic wipes container may not withstand an automatic washing process (e.g., the container may be damaged).
Accordingly, it would be desirable to provide a reusable wipes container having a soft, cloth-like outer surface that feels warm to the touch. It would also be desirable to provide a reusable wipes container that can be machine washed. It would further be desirable to provide a container that influences a consumer's perception of a feature of the substrate disposed inside the container.
In order to provide a solution to the problems stated above, there is disclosed herein a reusable container for storing and dispensing wipes. The wipes container comprises two or more shells configured to act cooperatively to define an interior storage space. The two or more shells are at least partially separable from one another to enable a user to replenish a depleted supply of wipes in the container. At least one of the shells includes an opening that enables a user to access at least one wipe stored in the interior storage space. The container also includes a synthetic polymer foam disposed on at least a portion of one of the shells. The synthetic polymer foam has an Effusivity value at 23° C. and 32° C. of less than about 550, according to the Sensory Warmth Test.
Definitions
“Cloth-like” means a material exhibits the physical properties of a substrate made from naturally occurring fibers such as, for example, cotton, hemp, cellulose, silk, wool, flax, combinations of these and the like.
“Disposed on” and variations thereof refer to the placement or position of one element relative to another element, where the elements are connected to or in physical contact with one another. For example, when a first element is disposed on a second element, the first and second elements may be joined together or formed together to provide an integral or unitary article. A first element may also be disposed on a second element when the first element is applied to the second element, for example, by a printing method or a coating method.
“Effusivity” is the measure of how warm or cold an object or surface feels to a typical human. Generally, a material with a higher effusivity feels colder than a material with a lower effusivity, when both materials are the same temperature. For example, steel has a relatively high effusivity and cotton has a relatively low effusivity, therefore a cotton object will typically feel warmer than a steel object when both objects are the same temperature. Effusivity is calculated as the square root of the product of the thermal conductivity, density, and heat capacity of the material (see the equation below).
E=√kρcp
Where:
E=effusivity(W*s1/2/m2*K)
k=thermal conductivity(W/m*K)
ρ=density(kg/m3)
cp=heat capacity(J/kg*K)
“Foam” refers herein to a material in a relatively lightweight (when compared to a nonfoamed state) open or closed cellular form resulting from the introduction of, for example, gas or other bubbles during manufacture of the material. “Foamed” means a material that has been converted from a nonfoam material to a foamed material. One nonlimiting example of a foam is commercially available EVA foam.
“Joined” refers herein to the attachment together of two or more components, either by direct affixment of a first element to a second element or by affixment of the first element to an intermediate element which is affixed to the second element.
“Moisture impermeable” means that an element resists and, ideally, prevents the passage of liquid and/or gaseous compositions (e.g., water and/or water vapor) from one side of the element to the opposing side of the element. For example, a wipes container for storing wet wipes will typically include one or more walls that resist the passage and/or penetration of liquid water and water vapor through the wall of the wipes container in order to prevent or at least delay moisture loss from the wet wipes. Thus, the walls of the container are said to be moisture impermeable.
“Nonwoven” refers to a porous, fibrous structure made from an assembly of continuous fibers, coextruded fibers, noncontinuous fibers or combinations thereof, without weaving, knitting, or felting. Non-limiting examples of suitable processes for making a nonwoven include spunbonding, carding, meltblowing, air laying, wet laying, coform, and the like. The nonwoven structure may comprise one or more layers of such fibrous assemblies, wherein each layer may include continuous fibers, coextruded fibers, noncontinuous fibers and combinations thereof.
“Removable” means that when a component is separated there is little or no damage to the component itself or the surrounding components, which would impair the use of the article or any component thereof.
“Reusable” means that a component may be used more than once for the same function without showing significant loss of utility or degradation of properties.
“Substrate” refers to the underlying material of which an element or component is made. In a 2-layer laminate structure, for example, each layer of the laminate may include the same or different materials, which materials may both be substrates. However, it is to be understood that in certain embodiments only the base layer of the laminate may be referred to as the substrate. Additionally, the laminate itself may also be a substrate for use in forming yet another component.
“Synthetic” refers to a composition or material that typically does not occur naturally (i.e., not produced in nature other than through the action of a human).
“Unitary” refers to an undivided container having two or more shells formed as a single article from the same piece of polymeric foam material.
“Wipe” refers a fibrous substrate, for example a nonwoven, used for cleaning skin and other surfaces. “Wet-wipe” refers to a wipe that includes more than 10% of a liquid composition by weight based on the weight of the wet-wipe. The liquid composition may be impregnated into the wipe or the liquid composition may be fugitive (i.e., free to move from one portion of the wet wipe to another portion).
Various types of disposable wiping products such as, for example, wipes, facial tissues, bath tissues, paper towels, and napkins are commonly used by consumers. Such wiping products can include dry products or saturated or pre-moistened wiping products. Saturated or pre-moistened wiping products are used in a variety of different wiping and polishing applications. Pre-moistened wipes are commonly sold in a stack of individual, folded sheets packaged in a plastic container for use as baby wipes. In other applications, the wipes are treated with an antibacterial agent and packaged as a sanitary wipe. Whether the wiping products are wet or dry, it may be desirable to provide a container for storing and dispensing the wiping products.
It may be desirable to provide a unitary wipes container formed entirely or almost entirely out of the same material, for example, by a blow molding process. In such an embodiment, the wipes container may include one or more shells.
The wipes container 1 may include one or more openings 6 for enabling a user to access wipes stored in the interior storage space 10, for example, by dispensing individual wipes through the opening 6. In certain embodiments, the top shell 7 may include an oval shaped opening 6 that extends through the top shell 7 to the interior storage space 10. It is to be understood, however, that any number of openings 6 in any suitable shape(s) are contemplated herein. For example, the opening 6 may be in the shape of one or more animals, letters, numbers, or geometric patterns. The container 1 may also include a lid 5 for covering the opening 6. In certain embodiments, wipes stored in container 1 may be wet wipes, and the wipes container 1 may include a lid 5. The lid 5 may be manipulated by a user to cover the aperture 6. The lid 5 may be formed from a material that is liquid or vapor impermeable, such that when the lid 5 is closed the amount of moisture loss from any wet wipes stored in the container 1 is at least reduced. The lid 5 may be configured to open and close over the opening 6 by any means commonly known in the art. Suitable examples of openings 6 and lids 5 for wet wipes containers are disclosed in U.S. Publication No. 2009/0050504, filed on Jul. 18, 2008 by Sawin, et al. In certain embodiments, the opening 6 may include a moisture impermeable covering 9. The covering 9 may be configured to reduce the effective surface area of the opening 6 through which moisture (e.g., water vapor) can escape from the interior storage space 10, and thereby further reduce the amount of moisture loss that may be experienced by wet wipes stored in the container 1. The container 1 may include a seal, for example, a gasket or plug seal around the edge of the lid 5, the opening 6, the first shell 7, and/or the second shell 8. The lid 5, covering 9, and seal may function together or independently to extend the useful life of wet wipes disposed in the interior storage space 10. Suitable examples of lids 5, coverings 9, openings 6, and seals are described in U.S. Pat. No. 6,910,579, issued on Jun. 28, 2005 to Reinke, et al.
In certain embodiments, the wipes container 1 may include indicia 12 for providing a variety of information to a user of wipes such as, for example, a type of wipes disposed in the container 1, product features, instructional information, promotional information, interactive features, manufacturer information, and the like. The indicia may include visual, audible, tactile, and/or olfactory cues. For example, the indicia 12 may include one or more raised portions such as a pattern of dots that form one or more geometric patterns. In such an example, the indicia 12 may provide both a visual and a tactile cue to a user. In another example, the indicia 12 may include one or more depictions of stars or a variety of other objects, animals, or patterns. The indicia may be disposed on any portion of the container 1 such as, for example, an outer wall 13, 14 of the top shell 7 or bottom shell 8, respectively. In addition or alternatively, the indicia 12 may be disposed one or more portions of an inner wall 15, 16 of the top shell 7 or bottom shell 8, respectively. In certain embodiments, the indicia may be provided on a surface of the container 1 through a molding process used in the manufacture of the container 1. For example, a mold used to form the container may include one or more patterns that are transferred onto a surface of the container when the thermoplastic container material is compressed in the mold. The pattern may include textural features that can be detected by a user (e.g., as visible patterns, as smooth or rough portions or as regions of differing effusity, thermal conductivity, density, and/or hardness). The indicia may be disposed on one or more discrete portions of the container that are spaced apart from one another, or the indicia may be disposed relatively uniformly over the entire container 1.
It may be desirable to provide an actuator 2 on the container 1 that enables a user to at least partially open the lid 5. The actuator 2 may be, for example, a button that works cooperatively with a spring such that when a user pushes the button the spring releases stored energy to at least partially open the lid 5. The wipes container 1 disclosed herein may be configured to include any suitable actuator 2 commonly known in the art and is not limited to a push button. The container 1 may also include a closure indicator. The closure indicator may be a sound that indicates to a user when the lid 5 is closed such as, for example, an audible “click” sound. The closure indicator may additionally or alternatively include visual and/or tactile cues to indicate to a user that the lid 5 is closed. The closure indicator may be configured as an integral part of the actuator 2 or may be a separate component.
In certain embodiment, it may be desirable to provide a unitary wipes container. The unitary wipes container may include one or more additional components such as, for example, a lid or an actuator formed from the same or different polymeric material in the same or a subsequent process step. Alternatively, it may be desirable to form EVA shells as discrete components, and then join the shells together in one or more subsequent steps. It may be desirable to form and/or join the shells in one or more first process steps and then form and/or attach additional components (e.g., a lid, fastener, actuator, and the like) in one or more subsequent process steps. It is to be understood, however, that one or more of the shells and/or one or more other components of the wipes container may be formed and/or joined together in any number of simultaneous or sequential process steps.
Warm, Cloth-like Wipes Container
Cotton and other naturally occurring fibers are common ingredients in textile products such as clothes, bed sheets, blankets, and other articles commonly referred to as cloth articles. Cotton is typically used in textile articles because at least some consumers find the texture and feel of cotton to be desirable. It is believed, without being limited by theory, that a wipes container comprising one or more outer surfaces or surface portions having an effusivity value or range of effusivity values closer to that of cloth may provide a more desirable wipes container than commonly known plastic containers and packages. However, constructing wipes containers from natural fibers such as cotton may increase the cost of producing wipes containers and/or introduce other drawbacks that make the use of such natural fibers in the construction of wipes containers undesirable. For example, cloth containers may not provide a suitable moisture barrier and/or consumers may find the softness or flimsiness of cloth containers to be a sign of poor quality. Surprisingly, it has been found that certain synthetic materials such as, for example, foamed synthetic polymeric materials may be used to provide suitable wipes containers with an effusivity similar to or the same as cotton and a hardness which may be perceived by consumers as a sign of desirable quality. Examples of synthetic polymeric materials include polyolefins such as polypropylene, polyethylene, low density polyethylene, medium density polyethylene, polybutylene; polyurethanes; and the like. One particularly suitable example of a foamed, synthetic material for use herein includes foamed poly(ethylene vinyl acetate) (“EVA”). EVA is typically made by copolymerizing ethylene and vinyl acetate monomers. The EVA may be foamed and formed into the desired shape by any suitable means known in the art. Suitable examples of EVA and methods of making and shaping EVA foam are described in PCT Publication No. WO 01/02473, filed by Hsu, et al., on Jun. 28, 2000. EVA foams may include some percentage of EVA such as, for example, greater than or equal to 1% EVA by weight, based on the weight of the EVA foam. However, difficulties may arise when attempting to produce EVA foams that have relatively low levels of EVA (e.g., less than 5%). Therefore, it may be desirable to select EVA foams that are greater than 10% EVA by weight, based on the weight of the EVA foam, for example, between 12% and 18% EVA. Higher levels of EVA may also be used, for example, any amount of EVA between 18% and 100%, as long as a wipes container that includes such EVA foam provides the desired effusivity value.
The physical and/or chemical properties of polymeric materials such as EVA may vary depending on, for example, the density, thickness, method of making, and/or polymer chain length of the polymer. The physical and/or chemical properties of EVA and other polymeric materials may also be selected or adapted to cover a wide range of values depending on the desired use of the polymeric material. For example, the EVA used in connection with the shoe sole described in U.S. Pat. No. 4,396,568, filed on Jul. 17, 1981 by Voll, et al., may have different property requirements than the EVA used in the multilayer tube described in U.S. Pat. No. 4,707,389, filed on Sep. 30, 1983 by Ward. With regard to the wipes containers disclosed herein, it is believed, without being limited by theory, that the material property of effusivity may be particularly important for characterizing the synthetic polymer material. Suitable effusivity values for the presently disclosed wipes containers may include an Effusivity value at 25° C. and 32° C. of less than 550, for example, from 100 to 400, 200 to 300, or any value within these ranges, when measured according to the Sensory Warmth Test detailed below. A particularly suitable example of a synthetic polymeric material for use in the wipes containers disclosed herein is thermomolded EVA sold under the product name Solatex 40, available from Tacosola, located in Novo Hamburgo, Brazil. Thermomolding or compression molding, as it is sometimes referred to by those of ordinary skill in the art, involves a method for processing flat material such as a sheet of EVA into a finished three-dimensional article such as a wipes container, wipes container shell, or other element. The process typically begins when a flat sheet of material, e.g., a sheet of laminated or unlaminated EVA foam is placed in a mold such as, for example, a two-piece mold. The mold is then brought into contact with the EVA sheet along with a suitable amount of heat and pressure such that the flat sheet of EVA foam conforms to the shape of the mold without breaking, cracking, or suffering any other undesirable physical defects. The mold is then removed from the EVA foam, leaving the semi-rigid foam article. As mentioned previously, the mold may include surface features that impart a texture and/or pattern to the EVA foam.
In certain embodiments, the polymeric foam disclosed herein may also include one or more additives. The additives may be used to provide desired chemical and/or physical features to the container such as, for example, colors, colorfastness, scent, and/or texture. Suitable examples of additives include, without limitation, fire retardants; metallocene; thermo chromatic pigments; UV indicators; UV inhibitors; anti-microbial compositions; carbonates; peroxides; lubricants; fragrances such as essential oils or perfumes; shell hulls, shell hull portions and ground shell hulls.
In certain embodiments, it may be desirable to provide a wipes container that includes a synthetic fabric such as, for example, a polyester fabric laminated to the outer surface of one or more of the shells or one or more portions of one or more shells.
In some instances, a user of, for example, the wipes container 101 shown in
It is commonly known that the effusivity of a material is a function of the density, heat capacity, and thermal conductivity of the material. Thus, the effusivity of a synthetic polymeric material may be similar or the same as the effusivity of a natural cloth material, but one or more of the density, heat capacity, and thermal conductivity may be different than the cloth material. It is believed, without being limited by theory, that the effusivity related properties such as, for example, the density of a foam material used in the making of wipes containers may also influence a consumer's perception of the desirability of the wipes container and/or the wipes that are stored in the wipes container. Thus, if the foam is too dense, a consumer may perceive the wipes container as being too hard or having physical characteristics similar to those of a typical hard, plastic wipes container. On the other hand, if the density of the wipes container material is too low, a consumer may perceive the wipes container as being, for example, too flimsy and/or too porous to provide a suitable reusable container for storing wipes such as, for example, wet wipes. Therefore, it may be desirable to select and/or adapt the foam for use in the reusable foam wipes containers described herein from synthetic polymeric foams having a density of any value between 30 and 150 kg/m3, for example, 80, 100, 120, 140 kg/m3 or any other value in this range. In certain embodiments, however, the density of the polymeric foam may be greater than 250 kg/m3 (e.g., between 250-800 kg/m3, 300-500 kg/m3; 350-450 kg/m3 or any value within these ranges) and the container may still have a suitable effusivity and/or thermal conductivity. For example, a polymeric foam material may be joined to another material to form a laminate having the desired properties. In another example, other properties of the polymeric foam (e.g., hardness) may be selected or altered to provide a container that has a suitable effusivity and is perceived by consumers as having desirable properties. It may also be desirable to select and/or adapt a foam material having a Shore A hardness of between 38 and 90; between 50 and 70; between 40 and 60; or between 45 and 55. A suitable method for measuring density is described in ASTM D3575-08. A suitable method for measuring Shore A hardness is described in ASTM D2240-05. It may also be desirable to select a foam having a Thermal Conductivity value of between 0.04 and 0.190 W/mK, for example, 0.01, 0.03, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10 W/mK, or any other value in this range, as determined according to the Sensory Warmth Test.
Table 1 below illustrates Effusivity values at 23° C. and 32° C., Thermal Conductivity values at 23° C. and 32° C., density values, and Shore A hardness values for a variety of materials. The Effusivity and Thermal Conductivity values shown are determined according to the Sensory Warmth Test described in more detail below. The uncompressed samples are not substantially modified from the condition in which they are received from the supplier, except for the disclosed modifications related to sample preparation. Compressed samples (i.e., Samples 8C, 9C, 11C and 12C) are prepared by placing a sheet of uncompressed thermoplastic foam material into the bottom piece of a two piece mold fitted on a Model C Carver Laboratory Press available from Fred S. Carver, Inc. Wabash, Ind. The uncompressed sample is sized to fit in a 75 mm×75 mm square. The uncompressed sample is compressed such that the compressed thickness of the sample in the mold and under compression is one half of the uncompressed thickness. An aluminum spacer plate is placed between the two pieces of the mold to ensure the proper thickness is achieved. The two pieces of the mold are brought together by moving the bottom piece of the mold toward the top piece of the mold until 1500 pounds of force is being applied by the press. The pieces of the mold are held together for ten minutes at a temperature of 225°±10° C. The thermoplastic material is then cooled to room temperature (i.e., 23° C.±2° C.). Molded samples are thermomolded samples prepared by the supplier. Textured samples are prepared in the same way as molded samples, except the mold includes a plurality of indentation or dimples that produce corresponding raised portions uniformly across the entire outer surface of the sample. Pattern samples are prepared in substantially the same way as textured samples, except that the indentations in the mold may are not uniformly dispersed, but arranged to produce a particular pattern on portion(s) of the sample. Samples that are textured and/or patterned have a textured/patterned side and a smooth side opposed thereto. Molded and compressed samples, which are not textured/patterned, have two smooth sides. While particular examples may disclose forming raised portions on the surface of the sample with indentations in the mold, it is to be understood that any known means of forming patterns on thermomolded materials is contemplated herein (e.g., raised areas in the mold which produce dimples in the material). Sample 1 is thermomolded 12% EVA foam commercially available from Extramold JOMO, located in Novo Hamburgo, Brazil. Sample 2 is the thermomolded EVA foam of sample 1 with a 106 gsm polyester fabric laminated to the EVA foam during the thermomolding process. Sample 3 is unmolded 12% EVA foam sold under the product code MINICEL T600 by Sekisui Voltek, Lawrence, Mass. Sample 4 is unmolded 12% EVA foam sold under the product code MINICEL T200 by Sekisui Voltek. Sample 5 is unmolded 18% EVA sold under the product code MINICEL G200 by Sekisui Voltek. Sample 6 is unmolded low density polyethylene sold under the product code 2A by Sekisui Voltek. Sample 7 is 1 mm thick, injection molded polypropylene taken from a FRESH MATES brand wipes container available from the Procter & Gamble Company. It is believed that the material of Sample 7 is representative of material commonly used in the making of hard, plastic wipes containers. Sample 8 is uncompressed 18% EVA foam sold under the product code 12G by Sekisui Voltek. Sample 9 is uncompressed 12% EVA foam sold under the product code 10EO by Sekisui Voltek. Sample 10 is the foam of sample 1 laminated to a 255 g/m2, interlock woven fabric blend of polyester and cotton sometimes referred to as terry cloth. The terry cloth portion of the laminate of Sample 10 is an absorbent uncut pile fabric with loops forming the pile. One side of the fabric is smooth and one side is terry. Sample 11 is uncompressed 12% EVA sold under the product code 12HPT from Sekisui Voltek. Sample 12 is uncompressed EVA foam sold under the product code Solatex 40, available from Tacosola, Novo Hamburgo, Brazil. Sample 13 is a clear, 50 micron polypropylene film available from Diversapack, LLC, Marengo, Ill. sold under the product number T502-038. The polypropylene film of Sample 13 may be used in the packaging of wipes products and is sometimes referred to as flow wrap by those of ordinary skill in the art of wipes and wipes packaging. Sample 14 is a 106 gsm polyester fabric obtained from the Jo-Ann Fabrics, Cincinnati, Ohio. Sample 15 is a 112 gsm cotton fabric material available from Jo-Ann Fabrics. Sample 16 is the EVA foam of Sample 1 with the polyester of Sample 14 placed over the surface of the EVA foam to be tested, but the polyester was not laminated to the EVA foam. Sample 17 is unmolded EVA foam sold under the product code 1642 by Tacosola. Sample 18 is the EVA foam of Sample 17 except molded. Sample 19 is the EVA foam of sample 17 except molded and textured. The textured side of sample 19 is tested. Sample 20 is the EVA foam of sample 17 except molded, textured, and patterned. The textured/patterned side of sample 20 is tested. Sample 20B is the EVA foam of sample 20 except the smooth side is tested. Samples 8C, 9C, 11C, and 12C are the EVA foams of samples 8, 9, 11, and 12, respectively, but compressed.
As can be seen from Table 1, certain EVA foam materials may provide desirable effusivity, thermal conductivity, density and/or hardness properties for a wipes container as described herein, while certain other EVA foam materials may not. Further, Table 1 also shows that certain processes such as molding, texturing, and/or patterning may alter the properties of the EVA foam.
In addition to having a more cloth-like surface, a wipes container that includes a polymeric foam material may also be washable. As used herein, “washable” means that an article can be washed more than 2 times in a typical washing machine or dishwasher without losing any structural or functional features. For example, a washable wipes container can be washed on the “normal” cycle in a commercially available washing machine using a typical household laundry detergent such as, for example, TIDE brand laundry detergent, available from the Procter & Gamble Co., Cincinnati, Ohio, and still function substantially the same as it did prior to washing. In another example, a washable wipes container as described herein may be washed in a commercially available dishwasher using a typical dishwashing detergent such as, for example, CASCADE brand dishwashing detergent available from the Procter & Gamble Co., without losing any structural or functional features. After washing, the washable wipes container will still open and close as it did before washing and any other container elements such as a fastening mechanism and/or a lid will still function without any noticeable difference in performance.
In addition to the advantages described above, a container having a particular effusivity at its surface may also influence how a consumer perceives the product stored in the container. For example, it is commonly known that at least some consumers prefer wipes having a thicker substrate and that such consumers may associate a cleaning benefit with the thicker wipe substrate. It is believed, without being limited by theory, that a wipes container having an effusivity similar to cloth, for example, cotton cloth may cause a consumer to perceive the wipes in the cloth-like container as being thicker than the wipes in a container that does not have a cloth-like surface. Other perceptions that a consumer has for various properties of wipes in a cloth-like container may be influenced in a similar manner. For example, a consumer may perceive the cleaning performance of such a wipe as being better; the quality of the wipes as being higher; the wipe being better for use on the skin of a baby; the wipe being softer and gentler; the wipe having an overall better appeal; or combinations of these.
Table 2 below shows a summary of the results of a consumer test to determine if the effusivity of a container is a factor the influences how a consumer perceives various properties of a wipe. The values shown in Table 2 are averages of the individual scores given by 17 test subjects. The consumer test for generating the data shown in Table 2 is performed as follows. The test subjects are asked to put there hand in an enclosed box. Inside the enclosed box is a material sample, i.e., one of Samples A-F shown in Table 2. All of the samples are 112 mm long by 35 mm wide. Sample A is a 50 micron thick, glossy, laminated film of biaxially oriented polypropylene and linear low density polyethylene sold under the product code 70XL-1661, by Nordenia U.S.A., Jackson, Mo. Sample B is a 50 micron thick, matte, laminated film of biaxially oriented polypropylene and linear low density polyethylene sold under the product code B1C33/8, by Nordenia U.S.A., Jackson, Mo. Sample C is a 1.0 mm thick sample from a HUGGIES SENSITIVE brand disposable wipes container available from Kimberly-Clark Worldwide, Inc., Delaware. Sample D is a 3.0 mm thick sample of the EVA foam material described as Sample 1 in Table 1 above. Sample E is a 3.0 mm thick sample of the thermomolded EVA foam described as Sample 10 in Table 1 above. Sample F is a 3.0 mm thick sample of the EVA foam described as Sample 6 in Table 1 above, but which has been modified to include a textured surface. The textured surface is produced during the compression molding process by placing an open weave fabric having a circular pattern on the surface of the EVA sheet prior to molding. After molding (i.e., after application of the mold, heat, and pressure), the fabric is removed. The open weave pattern of the fabric is left on the foam resulting in raised circles that are about 0.5 mm in height and 3.0 mm in diameter and cover substantially the entire surface of the foam. None of the material samples in the enclosed box are visible to the test subjects. After placing a hand in the enclosed box, the test subjects are asked to rub the material sample with their index finger and middle finger for five seconds. Next, the test subjects are asked to push on the sample with their index finger and middle finger for five seconds. At no time do the test subjects see or handle a wipe during the test. After completing the requested tasks for all of the material samples, the test subjects are asked to rate the samples on a scale of 1-9 (1 being poor and 9 being excellent) according to the following instructions: 1) please rate each package material for containing a product that would provide better cleaning; 2) please rate each package material for containing a product that would be of high quality; 3) please rate each package material for containing a product that would be good for your baby's skin; 4) please rate each package material for containing a product that would be soft & gentle; 5) please rate each package material for containing a product that would be thick; 6) please rate each package material for its overall appeal.
As can be seen in Table 2, the EVA foam in Sample D received the highest average rating for thickness, overall appeal, and better cleaning. Thus, the use of a particular material such as a foamed EVA material may provide the unexpected benefit of improved consumer perception of a product that the consumer cannot see or feel. In the case of a wipes container, the consumer may prefer one wipes product over another based solely on the textural sensory perception provided by the container, which could lead to a tangible commercial benefit of increased sales.
The objective of the Sensory Warmth Test is to determine the Effusivity value and Thermal Conductivity value of a material. The two properties are measured by the TCi analyzer simultaneously. The tests are performed in environmental conditions of 23° C. and 32° C.±2° C. and 20%±4% relative humidity.
Equipment: Mathis TCi thermal conductivity analyzer, available from Setaram Inc., Pennsauken, N.J.
Accuracy test/calibration
The TCi analyzer has a specified accuracy of 5%. The accuracy check is done prior to running test samples using the appropriate calibration standard (e.g., Pyrex (available from Corning, Inc., New York, N.Y.) for polymers, LAST-A-FOAM FR-6720 polyurethane foam (available from General Plastic Manufacturing Company, Tacoma, Wash.) for foams and fabrics and distilled water for films) as follows: Each standard is measured 10 times, and the average effusivity from the 10 measurements is compared to the known value of Effusivity for the standard to obtain the percent accuracy and to confirm the instrument was performing within the stated accuracy specification of 5%. The accuracy of the measurements conducted under specific environmental conditions can be examined by measuring calibration materials with the externally certified Thermal Conductivity values and Effusivity values under specific environmental conditions.
The method makes six measurements of effusivity and thermal conductivity. The first measurement is discarded and the remaining 5 measurements are averaged to give an Effusivity value and a Thermal Conductivity value. This is done on two locations on each sample. The average value from each location is averaged to obtain the value for the sample.
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm”.
Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
This application claims the benefit of U.S. Provisional Application No. 61/075,509, filed Jun. 25, 2008.
| Number | Date | Country | |
|---|---|---|---|
| 61075509 | Jun 2008 | US |
