COSMETIC PAD AND METHOD FOR ITS MANUFACTURE

Abstract

A cosmetic pad and a method of manufacturing the same. The cosmetic pad includes a layer of hydroentangled cotton-based fibers that form a coherent, soft and resilient, mildly abrasive, linting-resistant fibrous material body having substantially smooth top and bottom surfaces. During its rotary stamping and cutting from a web, the pad is provided with at least one pressure print in a predetermined location in the material body, the pressure print identically aligned on both the top and bottom surfaces of the material body and defining a compression pattern that extends between the top and bottom surfaces of the material body.

Description

TECHNICAL FIELD

[0001] The present invention relates generally to cosmetic pads. More particularly, the invention relates to the construction and performance of a cotton-based cosmetic pad having a high tensile strength, a high absorbency and a prolonged material memory.

BACKGROUND

[0002] Consumer requirements regarding the function and appearance of cosmetic pads have been researched by many of the principle manufacturers in the field. The results show that though users want a cosmetic pad that efficiently removes makeup/nail polish and absorbs the same without smearing, users prefer and are drawn to a cosmetic pad that has a soft, luxurious texture and that presents an esthetically pleasing and higher quality appearance.

[0003] Conventional and commercially available pad constructions lack the structural strength and integrity required for effective cleansing and treatment. A significant amount of lint is generated by conventional pads when rubbed, leaving undesirable lint residue on skin or nails when used to remove makeup or nail polish. Furthermore, conventional pads often fall apart during use, layers of the pad separating from each other as pressure is applied and moisture is absorbed.

[0004] There is significant prior art which addresses some of these concerns. Kemp in U.S. Pat. No. 3,953,638 discloses multi-ply absorbent wiping products comprising two identical pattern-embossed outer plies of absorbent fibrous material bonded to a central fibrous absorbent layer. Goodbar in U.S. Pat. No. 4,259,958 discloses a multilayered pad composed of wood pulp fiber. Delvaux discloses in U.S. Pat. No. 4,443,512 an absorbent article with densified areas comprising a pad of absorbent material sandwiched between a backing sheet and a top sheet. The absorbent material is a wood fluff or the like and the absorbent article is embossed on either side or both sides so that the absorbent material is compressed in discrete areas.

[0005] Gerhartl in U.S. Pat. No. 5,480,699 discloses a three-layered pad with the two outer layers being embossed and the central layer being relatively uncompressed. This product has poor structural integrity and deposits lint on the user's skin and finger nails during make-up removal or lotion application.

[0006] Horn in U.S. Pat. No. 5,302,446 discloses a laminated two-sided skin care wipe which uses more than 50 weight % of thermally fusible thermoplastic fibers to provide lamination and pad strength. This composition reduces the absorbency and increases the surface abrasiveness excessively.

[0007] Ziltener et al. in U.S. Pat. No. 7,192,630 disclose a pad formed of one or more plies which are connected in their edge region and thus have a compression region on their circumference. This compression region is stamped into the pad at a certain distance from the circumference of the pad, the material fibers directed outward from the compression region and being so long that they are not rigid but rather slightly flexible. This construction increases the cohesion of the plies and provides softer edges. Unfortunately, significant lint is still generated by this product, and the pad structure breaks down during use.

[0008] None of the previously described cosmetic pads and/or pad constructions have successfully combined the advantages of absorbency, pad strength and esthetic appeal, while providing an economically viable product.

[0009] Consequently, there exists a need in the industry to provide an improved cosmetic pad.

SUMMARY

[0010] It is an object of the present invention to provide a cosmetic pad having improved efficacy, structural integrity and esthetic appeal.

[0011] In accordance with a broad aspect, the present invention provides a cosmetic pad comprising a layer of hydroentangled cotton-based fibers forming a coherent, soft and resilient, mildly abrasive, linting-resistant fibrous material body, the material body having substantially smooth top and bottom surfaces; and a pressure print in a predetermined, central location in the material body, the pressure print identically aligned on both the top and bottom surfaces of the material body and defining a compression pattern that extends between the top and bottom surfaces of the material body.

[0012] In accordance with another broad aspect, the present invention provides a method of manufacturing a cosmetic pad, the method comprising hydroentangling cotton fibers to form a web of coherent, soft and resilient, mildly abrasive, linting-resistant fibrous material having substantially smooth top and bottom surfaces; heating the web; and applying a rotary dye to the heated web for stamping and cutting out a plurality of pads from the web, the step of applying a rotary dye to the heated web including defining at least one identically located pressure print in each of the plurality of pads simultaneously with the cutting of the plurality of pads, the pressure print defining a compression pattern that extends between the top and bottom surfaces of the respective pad.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIGS. 1A and 1B show, in top and bottom views respectively, a cosmetic pad, according to a non-limiting example of implementation of the present invention;

[0014] FIGS. 2A and 2B illustrate a system for the production of the pad shown in FIG. 1, according to a non-limiting example of implementation of the present invention; and

[0015] FIG. 3 illustrates a rotary dye cut tool, according to an example of implementation of the present invention.

DETAILED DESCRIPTION

[0016] The present invention is directed to a cosmetic pad having a high tensile strength, a high absorbency and a prolonged material memory, and to a method of constructing the same.

[0017] As used herein, the term "cosmetic pad" refers to a pad that can be used to apply or remove make-up or other cosmetics, cleanse skin surfaces, apply emollients or other liquid materials to the skin, remove nail polish and similar task.

[0018] As used herein, the term "cotton" refers to scoured and bleached cotton fiber wherein a finish has been applied to the cotton surface to permit subsequent processing. While cotton is a cellulosic fiber, it is differentiated from other cellulosic fibers, such as wood pulp, by its strength, absorbency and fiber length.

[0019] As used herein, the term "pressure print" refers to a defined, visual pattern that is formed in a web, and appears on the web surface, when rough fiber surfaces within the web are forced together at one or more specific locations, following a specific pattern, during rotary die stamping.

[0020] As used herein, the term "compression pattern" or "compression region" refers to a pattern or region arising in a web as a result of compressing web fibers according to a specific design during rotary die stamping and/or cutting, where the rotary die stamping compresses the web fibers and creates a high frictional bond that holds the compressed web fibers tightly together in the specific design layout.

[0021] The term "machine direction" as used herein refers to the direction of travel of the forming surface onto which fibers are deposited during formation of a material.

[0022] The term "cross-machine direction" as used herein refers to the direction in the same plane, which is perpendicular to horizontal machine direction.

[0023] As used herein, the term "machine direction tensile" (hereinafter may be referred to as "MDT") is the force applied in the machine direction to rupture a sample in substantial accordance with TAPPI test procedures and may be reported as grams/centimeter of width.

[0024] As used herein, the term "cross direction tensile" (hereinafter may be referred to as "CDT") is the force applied in the cross direction to rupture a sample in substantial accordance with TAPPI test procedures and may be reported as grams/centimeter of width.

[0025] As used herein, the term "basis weight" (hereinafter may be referred to as "BW") is the weight per unit area of a sample calculated in accordance with ASTM test procedure D-3776-96, Option C, and may be reported as grams per square meter or abbreviated as gsm.

[0026] As used herein, the term "hydroentangle" or "hydroentangling" refers to a process wherein a web of fibrous material consisting of one or more types of fibers are subjected to a pattern of high-velocity water jets, which entangle the fibers to achieve mechanical bonding without binder materials or thermal bonding.

[0027] As used herein, the term "spunlaced fabrics" refers to a web of material consisting of one or more types of non-continuous fibers, where the fibers are hydroentangled to achieve mechanical bonding without binder materials or thermal bonding.

[0028] As used herein, the term "surface cohesion" refers to the resistance of the fibers on the surface of the web from being removed by abrasion or rubbing.

[0029] FIGS. 1A and 1B illustrate a cosmetic pad, in accordance with a non-limiting example of implementation of the present invention. The pad 100 consists of a heavy-weight layer of hydroentangled cotton-based fibers, which form a coherent, soft and resilient, mildly abrasive, linting-resistant fibrous material body 102. The material body 102 of the pad 100 is double-sided, having smooth, unapertured top and bottom surfaces 104 and 106, respectively. Although the exemplary pad 100 shown in FIGS. 1A and 1B is round in shape, it should be noted that different polygonal shapes are possible and included in the scope of the invention.

[0030] The preferred embodiment of a cosmetic pad according to the instant invention is constructed from an airlaid bleached cotton-based web that has been hydroentangled such that its outside surfaces are smooth, un-apertured and mildly abrasive. These outer surfaces possess excellent surface cohesion, which prevents linting during functional use. The areal basis weight is about 270 gsm (ranging between 260 and 280 gsm) and thus provides significant liquid capacity.

[0031] Note that the cotton-based web may be composed of 100% cotton or, alternatively, of a blend of cotton and one or more of various different materials, such as rayon, polypropylene, polyester and microfibres. The pure cotton itself is characterized by superior absorbency, textural properties and very high fiber-to-fiber cohesion. The preferred types of bleached cotton are cotton staple, cotton comber noils or cotton gin motes.

[0032] The bleached cotton fiber for the preferred embodiment should have the highest possible level of fiber-to-fiber cohesion for the best pad performance. Using appropriate fiber finish at minimum add-on levels ensures this.

[0033] Specific to the present invention, the pad 100 includes a defined pressure print 108 in a predetermined location in the material body 102. As shown in FIGS. 1A, 1B, this predetermined location may, in one example, be substantially centered with respect to the pad surface area. Alternatively, the predetermined location may be anywhere on the pad surface.

[0034] Note that, in a variant example of implementation, the pad 100 may include a plurality of defined pressure prints, positioned at different respect locations on the pad surface area.

[0035] The pressure print 108 is identically aligned on both the top and bottom surfaces 104, 106 and defines a compression pattern that extends between the top and bottom surfaces 104, 106 of the material body 102.

[0036] The pad 100 may also include a second, defined pressure print 110 in the material body 102, extending along a circumference of the material body 102. The pressure print 110 defines a compression region at a radial distance from the circumference of the material body 102, the compression region extending between the top and bottom surfaces 104, 106 of the material body 102 for defining an edge region of the pad 100.

[0037] It has been found that the compression pattern defined in the material body 102 of the pad 100 by the pressure print 108 provides an increased cleaning performance, an increased absorbancy and an extended material memory in the pad 100, compared to competitive pads. The compression pattern enables an optimum inner pad strength, even when moisturized, which provides for a highly absorbent pad. In the case of the extended material memory, this leads to a longer lasting pad, which does not lose its shape during use.

[0038] As will be discussed below, the pressure prints 108 and 110, and thus the compression patterns/regions, are formed by rotary dye stamping during the pad forming process. Since the natural surface of scoured cotton fibers is very rough, when these rough fiber surfaces are forced together at specific location(s) (e.g. along an edge or following a predefined pattern) during the die stamping and/or cutting or pad forming process, a high frictional bond is created between the fibers, as well as a significant degree of hydrogen bonding, which makes a strong and efficient bond.

[0039] Specific to the present invention, the pressure print 108 is characterized by a predefined, visually recognizable design. In the example shown in FIG. 1, the pressure print 108 is in the shape of a flower. Various different designs are possible, without departing from the scope of the invention. Advantageously, the visually recognizable design of the pressure print 108 contributes to and enhances the esthetic appeal of the cosmetic pad 100, lending a higher quality appearance to the pad 100 which appeals to consumers.

[0040] FIGS. 2A and 2B illustrate a system or machine for manufacturing cosmetic pads, according to a non-limiting example of implementation of the present invention. During the manufacturing process, a web or laminate of hydroentangled cotton-based fibers passes through a pad forming system or machine. This web may be pre-formed, presented in individual roll form and fed off this roll to the pad forming machine or, alternatively, may be formed within the system or machine in a first stage of the pad forming process.

[0041] The hydroentanglement process, also known as a spunlace process, is a nonwovens manufacturing process that employs high-pressure jets of water to entangle fibers and thereby provide fabric integrity. Softness, drape, conformability, excellent surface cohesion and high strength are the major characteristics that make spunlaced nonwoven unique among nonwovens.

[0042] The formed web, usually air-laid or carded, is first compacted and prewetted to eliminate air pockets and then water-needled. The water pressure generally increases from the first to the last injectors. Pressures as high as 2200 psi are used to direct the water jets onto the web. This pressure is sufficient for most nonwoven fibers, although higher pressures may be used in specialized applications to achieve higher tensile strength and lock in surface fibers more efficiently.

[0043] In general, cotton fibers are preferred for their high strength, pliability, plastic deformation resistance and water insolubility. Cotton fibers are hydrophilic, chemically stable and relatively colorless. Another advantage is that cotton has an inherent bonding ability caused by a high content of hydroxyl groups, which attract water molecules. As the water evaporates from the fabric, the hydroxyl groups on fiber surface link together by hydrogen bonds.

[0044] The web support system or conveyor and collector wire plays an important part in most nonwoven processes. This is especially true for the spunlaced process wherein it has a critical role. In this process, the pattern of the final fabric is a direct function of the conveyor wire design. By using the appropriate wire web support system, webs with a variety of smooth or apertured surfaces can be created.

[0045] Specific to the present invention, a web or laminate of hydroentangled cotton-based fibers with smooth outer surfaces is created, or alternatively received in a roll if pre-formed, and fed into the pad forming system or machine. The web is first heated, for example by passing the web through an embossing roller. Once heated, the web or laminate is then fed through one or more shear-type rotary dyes for simultaneous stamping and cutting out of the pads. The pressure applied by the rotary dyes to the pre-heated web both cuts out a plurality of pads and, simultaneously, identically stamps or embosses each of the plurality of pads produced.

[0046] Note that the cosmetic pads formed may be round, oval or any form of polygon in shape.

[0047] In a specific, non-limiting example of implementation of the present invention, the rotary dye cutting/stamping apparatus and process is designed to cut out a plurality of pads and to apply at least one identically located pressure print (and thus at least one corresponding compression pattern extending through the material body), and to seal the circumferential edge, on each pad produced.

[0048] FIG. 3 illustrates a rotary dye tool 300, according to a non-limiting example of implementation of the present invention. As seen, the rotary dye tool 300 presents on its outer surface a repetitive layout of shearing edges 302 and stitch patterns. The shearing edges 302 define a plurality of round pads. The edge stitch patterns 304 define the circumferential edges of each pad, while the design stitch patterns 306 define, within each pad, an identically located flower print, for example. When the pre-heated web of hydrotangled cotton-based fibers is passed through this rotary dye tool 300 during the pad forming process, the rotary dye tool 300 is operative to dye cut the web into the plurality of pads per the required shape and dimensions defined by the shearing edges 302. Simultaneously with this cutting, the rotary dye tool 300 is operative to stamp or emboss, in each formed pad, an edge pressure print and a floral pressure print, per the edge stitch patterns 304 and the design stitch patterns 306, respectively. As a result of the rotary dye tool 300 layout, these edge and floral pressure prints are identically located in each pad, identically aligned on top and bottom surfaces of the pad.

[0049] Effective pressure printing and edge sealing during the pad dye-stamping stage is a function of the shearing and compressive forces and their effect on the cohesion of the cotton-based fibers making up the pad. As mentioned above, the rough scoured cotton fiber surfaces, when forced together at specific locations defined by the rotary dye tool, under the tremendous pressure applied by the rotary dye, compress together with a high frictional bond and a significant degree of hydrogen bonding. The pressure delivered by the rotary dye during the forming and cutting of the pads results in clearly defined patterns (i.e. the at least one pressure print) in the pads.

[0050] Thus, the definition of the pressure print and of the compression pattern extending through the material body, as well as the sealing of the outside edge, of each pad is accomplished by the combination of the high shearing and compression forces created during rotary stamping/cutting. The low finish level and the correct moisture content of the pre-heated web optimize sealing. After stamping, the finished cosmetic pads are packaged.

[0051] The MDT and CDT strengths of the preferred embodiment pads were measured and were found to be, respectively, 2.4 kg/cm and 1.93 kg/cm of width. Surprisingly, competitive products were found to have significantly lower MD and CD tensile strengths. As an example a major competitive product was found to have MDT and CDT strengths that measured, respectively, 0.35 kg/cm and 0.06 kg/cm of width.

[0052] Although various embodiments have been illustrated, this was for the purpose of describing, but not limiting, the present invention. Various possible modifications and different configurations will become apparent to those skilled in the art and are within the scope of the present invention, which is defined more particularly by the attached claims.

Claims

1. A cosmetic pad comprising: a) a layer of hydroentangled cotton-based fibers forming a coherent, soft and resilient, mildly abrasive, linting-resistant fibrous material body, said material body having substantially smooth top and bottom surfaces; b) a pressure print in a predetermined, central location in said material body, said pressure print identically aligned on both said top and bottom surfaces of said material body and defining a compression pattern that extends between the top and bottom surfaces of said material body.

2. A cosmetic pad as defined in claim 1, wherein said pressure print is a first pressure print, said pad further comprising a second pressure print in said material body extending along a circumference of said material body, said second pressure print defining a compression region at a radial distance from the circumference of said material body, said compression region extending between the top and bottom surfaces of said material body.

3. A cosmetic pad as defined in claim 1, wherein said layer has an areal weight between 120 and 350 grams per square meter.

4. A cosmetic pad as defined in claim 1, wherein said layer has an areal weight of substantially 270 grams per square meter.

5. A cosmetic pad as defined in claim 1, wherein said pad has a minimum tensile strength of 1.2 kilograms per centimeter of said pad width in any radial direction.

6. A cosmetic pad as defined in claim 1, wherein said layer is airlaid before hydroentanglement.

7. A cosmetic pad as defined in claim 1, wherein said material body is characterized by a polygonal shape.

8. A cosmetic pad as defined in claim 1, wherein said first pressure print is characterized by a predefined, visually recognizable design.

9. A cosmetic pad as defined in claim 8, wherein said first pressure print is in the shape of a flower.

10. A method of manufacturing a cosmetic pad, said method comprising: a) hydroentangling cotton fibers to form a web of coherent, soft and resilient, mildly abrasive, linting-resistant fibrous material having substantially smooth top and bottom surfaces; b) heating the web; c) applying a rotary dye to the heated web for stamping and cutting out a plurality of pads from the web, said applying a rotary dye to the heated web including defining at least one identically located pressure print in each of the plurality of pads simultaneously with the cutting of the plurality of pads, the pressure print defining a compression pattern that extends between the top and bottom surfaces of the respective pad.