FIELD OF THE INVENTION
- BACKGROUND OF THE INVENTION
The present invention relates generally to plastic, polymeric fillers, stuffings and insulators and their use in pillows, cushions, mattresses, blankets, duvets, jackets and textiles.
Pillows and other cushions are often made with stuffings. These stuffings can include natural materials such as feathers or wool. However, these natural materials have many drawbacks. The natural materials can contain matter, such as quills, or contaminants that can have a detrimental effect on the properties of the stuffing. In addition, the natural materials can have unpleasant odor effects in certain environments and can be fairly costly. Natural materials can also have the additional drawback of causing allergic reactions in some users.
An alternative to natural stuffings is artificial stuffings. The artificial stuffings eliminate some of the negative characteristics of the natural stuffings. The artificial stuffings can be hypoallergenic, can minimize odor issues and can dispense with the use of hard materials such as quills. However, numerous artificial stuffings present drawbacks. Many materials that could be used for artificial stuffings have a low melting point which makes drying the stuffing in a conventional dryer without melting the stuffing difficult or impossible. In addition, many artificial stuffings do not behave similar to natural stuffings and exhibit less desirable loft and rebound characteristics than natural stuffings.
- BRIEF SUMMARY OF THE INVENTION
The present invention is designed to overcome some of the drawbacks of previous materials.
The present invention provides a stuffing, filler or insulator for use in pillows, cushions, blankets, textiles and the like. In an embodiment a stuffing or filler is comprised of pieces of plastic foam sheets. The foam pieces include gas bubbles that are enveloped within the foam. These bubbles provide for increased resiliency, springiness and other beneficial features. The foam sheets are shredded or torn into smaller pieces through the use of devices such as knives or other shearing instruments. The foam pieces in an embodiment have a thickness of approximately 180-3200 microns and a length of approximately 0.5-10 cm after shearing. The foam pieces can be used as a stuffing or filler in a pillow or comforter or can be used as a stuffing, filler or insulator in textiles.
In an embodiment, the foam pieces can be made from polyethylene or polypropylene blown foam or a combination of the two. The foam pieces can include antimicrobial agents and can exhibit hypoallergenic characteristics. The foam pieces also can exhibit beneficial loft and rebound characteristics which provide for an enhanced and more natural-feeling pillow.
- BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.
FIG. 1 shows schematically how the foam pieces of the present invention are produced from foam sheets.
FIG. 2 depicts an enlarged side view of a foam piece of an exemplary embodiment of the present invention.
- DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. Rather, the phrases and terms used herein are to be given their broadest interpretation and meaning. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof.
The present invention involves plastic material that can function as a stuffing, cushion, filler, insulator, absorber or other material suited for individual plastic matter. In one embodiment, the present invention involves foam sheets. These foam sheets are made from plastic or natural materials. Polypropylene, polyethylene, polyvinylchloride, nylon, polyester, epoxy, polyvinyl acetate, copolymers and other polymeric materials can be used in the foam sheets. In addition, in some embodiments, chemical or physical blends of different plastics can be used. The foam sheets can take the form of blown foam or other forms of foam sheets. The foam sheets are formed from processes well known in the industry, for example through use of blowing agents, including agents such as sodium bicarbonate, hydrazine, halocarbons, fluorocarbons or hydrofluorocarbons.
In some embodiments, the foam sheets include encapsulated gas. In the process of manufacturing the foam, gas can be embedded within the foam. Gas bubbles such as air or other gas can be incorporated into the foam and become enveloped in the foam sheets. Many of these gas bubbles are fully enclosed and thus the foam itself contains numerous gas filled bubbles within the structure of the foam.
These gas bubbles can impart certain properties to the foam. Foam containing these bubbles can exhibit increased resiliency and cushioning. The foam can feel soft and may rebound after compression. The gas bubbles can allow the foam to deform and then rebound to a post-deformation shape. The foam in some embodiments has a three dimensional structure that imparts a rich and pleasing hand-feel to the foam. The structure also can allow for loads to be displaced in three dimensions internally within the foam structure. The gas bubbles generally do not burst when a reasonable load is placed on them, such as a load similar to that of a human head resting on a pillow.
The foam sheets, in some embodiments have a thickness of approximately 90-5000 microns. In a preferred embodiment the foam sheets have a thickness of approximately 180-3200 microns. In an additional preferred embodiment the foam sheets have a thickness of approximately 360-1600 microns. In a further preferred embodiment the foam sheets have a thickness of approximately 360-800 microns. In a highly preferred embodiment, the foam sheets have a thickness of approximately 520-540 microns. In an additional highly preferred embodiment, the foam sheets have a thickness of approximately 780-800 microns. I a further highly preferred embodiment, the foam sheets have a thickness of approximately 380-410 microns.
In some embodiments, as shown in FIG. 1, initial long foam sheets 10 are manufactured into smaller foam pieces 20. One method of such manufacture involves the cutting or shredding of the foam sheets. In this method, foam sheets 10 are passed through rollers 14 and into a shearing chamber 30. The shearing chamber includes a plurality of knives or other shearing instruments 40. These shearing instruments spin around an axis. The foam sheets in the chamber are sheared by the knives into smaller pieces. These smaller pieces may be subjected to the knives on several occasions while the pieces remain in the chamber. Each time a foam piece is subjected to a shearing instrument it generally is sheared into a smaller piece.
In one embodiment, the shearing chamber also includes a screen 50. The screen 50 is sized to allow only foam pieces below a certain size to fit through the screen. Foam pieces of a larger size remain in the shearing chamber until they are sheared to a smaller size. After the foam pieces pass through the screen, they exit the shearing chamber. Foam pieces that have exited the shearing chamber are shown as 24 in FIG. 1. In some embodiments, sheets can be introduced into the shearing chamber at a rate of approximately 20-120 ft./min., preferably 40-90 ft./min. and more preferably 50-70 ft./min. In other embodiments, the sheets are torn or cut into smaller pieces by other mechanical or non-mechanical cutting or shearing processes.
In some embodiments, as shown in FIG. 1, plastic film sheets 16 can be introduced into the shearing chamber 30 at the same time as foam sheets 10. Through the shearing process, the film sheets will be sheared into film pieces 26. When the plastic film pieces reach a size small enough to pass through the screen 50, they can pass out of the shearing chamber 30 (as shown by plastic film pieces 28). The plastic film sheets 16 can be narrower or wider than the plastic foam sheets 10. Moreover, more than one film sheet and more than one foam sheet can enter the hearing chamber at the same time. The foam pieces and film pieces in FIGS. 1 and 2 are not drawn to scale.
The mechanical cutting, shearing or milling process creates foam pieces of a smaller length and width. In some embodiments, the length of the foam pieces ranges from approximately 0.5 cm to 10 cm. Preferably, the foam pieces have a length of approximately 1 to 8 cm, more preferably a length of approximately 1-6 cm and more preferably a length of approximately 2-4 cm. The manufacturing in some embodiments also may cause the foam pieces to exhibit a non-uniform shape. In such embodiments, the foam pieces contain numerous bends and deformations and varying lengths, and the foam pieces may vary in shape and size. The foam pieces can be generally separate from each other and generally not adhered to each other. Depending on the manufacturing process used, the foam pieces also can be created with generally uniform shapes and sizes and without bends or deformations. The foam sheets can have a ratio of length to thickness of approximately 500:1-4:1, preferably 150:1-10:1 and more preferably 100:1-25:1.
The foam pieces generally continue to contain gas bubbles after being subjected to the shearing, cutting or milling process in some embodiments. In some embodiments, as shown in FIG. 2, gas bubbles 60 (shown in dotted lines to indicate their position within a foam sheet piece) remain enveloped within the structure of the foam pieces 70. These gas bubbles may be generally randomly distributed through the foam pieces, as shown in FIG. 2, or may be evenly distributed. The foam pieces can exhibit resiliency and a springiness based on the interior characteristics of the bubbles as well as the exterior structure of the foam pieces themselves.
The encapsulated bubbles can provide for increased mechanical characteristics over stuffing made entirely of flat films. Foam pieces with enveloped bubbles, can have increased physical properties due to the structure of the interior of the foam, in addition to the exterior of the foam. The interior structure may allow for increased resiliency, flexibility, strength, elasticity and softness of the foam. The three dimensional structure may apportion weight internally along the x, y and z axis. In some embodiments some or all of the bubbles may be broken during the manufacturing stage. The broken bubbles 80 can provide for a rich three dimensional structure that allows for displacement of loads along three axis of dimension.
The foam pieces in some embodiments contain antimicrobials, antifungals, fire retardants, aromatic or medicinal compounds or other additives. In some embodiments additives, such as antimicrobials, can be added prior to formation of the plastic polymer foam, such as in the melt stage. The antimicrobial, anti-fungal or other additives impart beneficial properties to the foam pieces and increase their life cycle when used as a stuffing or insulator. Numerous antimicrobials and antifungals are known in the art and can be used in the present invention. In some embodiments, the antimicrobials or antifungals are added topically after foam formation or after milling or shearing rather than during the melt stage of foam formation.
The foam pieces in some embodiments are hypoallergenic. The foam pieces also can be chemically inert. Such foams can be highly useful in stuffings for pillows, mattresses and comforters, especially when used with compromised individuals, such as in a hospital or care facility.
In some embodiments, the foam pieces have a melting temperature that allows the foam pieces to be dried in a conventional drier. In some embodiments foams have a melting temperature of approximately 265-285 degrees Fahrenheit. In other embodiments, foams have a melting temperature of approximately 325-345 degrees Fahrenheit. In some embodiments, stuffings including foam pieces or stuffings consisting solely of foam pieces have a melting temperature of no less than 200 degrees. In other embodiments, stuffings including foam pieces or stuffings consisting solely of foam pieces have a melting temperature of no less than 250 degrees, 300 degrees or 350 degrees Fahrenheit.
The foam pieces of the present invention, in some embodiments, can be washed in conventional machines as well as dried. Such characteristics are useful when the foam pieces are used as stuffings in bedding materials, pillows, comforters, blankets, quilts, mattresses, or the like, including bedding materials used in multiple-user settings, such as hotels or hospitals. The foam pieces in some embodiments do not bunch together or migrate when subject to mechanical processes such as washing and drying.
The foam pieces of the present invention, in some embodiments, are soft and exhibit a pleasant hand feel. Although silicone or anti-friction agents can be added to the foam, the addition of silicone or these agents is not necessary to produce desired levels of softness and hand feel in some embodiments. When used in mattresses, in some embodiments the foam pieces of the invention can be incorporated into the main mattress or into a mattress topper. In some embodiments, mattresses that include at least a portion of the foam pieces of the present invention can exhibit reduced pressure in the mattress topper.
The foam pieces of the present invention can be used with a number of materials. In some embodiments, the foam pieces can be used as a stuffing. This stuffing can be used in pillows, cushions, pads, mattresses, comforters, textile products, insulators, jackets, quilts, pants, textiles, clothing, outer gear, furniture or other products that take a stuffing. The foam pieces can be used by themselves or with additives such as antimicrobials, antifungals, fire retardants or others, some of which are specifically discussed herein. The foam pieces also can be used in connection with other stuffings, insulators or materials. In some embodiments, the foam pieces of the present invention make up the majority of a stuffing or the material within an object such as a pillow, cushion or comforter. In other embodiments, the foam pieces make up the great majority or all of the stuffing. In still other embodiments, the foam pieces make up a minority, 25%, or less of the stuffing in the object, such as a pillow.
The foam pieces in some embodiments can be used in connection with films such as plastic films. Polyethylene film, polypropylene film, polyester film and nylon film are examples of plastic films that can be used with the foam pieces. One or more of these films can be sheared or shredded into film pieces. The films, in some embodiments, have a thickness of 5-100 microns, preferably 10-50 microns and more preferably 15-25 microns. After being sheared, the films in some embodiments have a length of approximately 0.5-20 cm, preferably 1-10 cm and more preferably 3-10 cm. This film can be combined with the foam before, during or after the shearing process. In one embodiment polyethylene foam sheets and polyethylene film sheets are placed into a shearing chamber at the same time. Each of the sheets is shredded and the resulting mixture contains pieces of the polyethylene foam and pieces of the polyethylene film. Other films or foam sheets, such as polypropylene film and foam, also can be run through the shearing chamber at the same time or separately.
In some embodiments, stuffings or fillers including foam pieces or stuffings or fillers consisting solely of foam pieces can exhibit a high degree of loft. The three dimensional structure of the foam pieces, the encapsulated bubbles and the exterior of the structure adds to the loft of the stuffing. Loft can be measured in relation to the density of the stuffing or filler after agitation or infusion of gas such as air. A loft coefficient for a stuffing or filler can be calculated by initially placing approximately 114 grams (4 oz.) of stuffing into a 15 liter graduated cylinder. The cylinder is closed and then vertically agitated for approximately 15 seconds. The edges of the cylinder are then briefly tapped to release foam pieces adhering thereto. The volume of stuffing or filler in the cylinder provides a correlation to the loft of the foam. The volume of stuffing or filler in the cylinder is the same as the loft coefficient. Stuffing or filler with a volume of 10 liters in the cylinder corresponds to a loft coefficient of 10. In this test, the maximum loft coefficient is 15. Stuffing or filler with a volume of 6.5 liters in the cylinder corresponds to a loft coefficient of 6.5. In some embodiments of the present invention, the stuffing or filler can have a loft coefficient of 5-15, preferably, 10-15 and more preferably 12-15.
In some embodiments, stuffings or fillers consisting partially of foam pieces or stuffings consisting solely of foam pieces can exhibit good rebound characteristics. After a deformation load placed on the stuffing or filler and removed, stuffings or fillers in some embodiments will move or rebound to a post-deformation shape and form. The stuffings or fillers may not rebound to their pre-deformation shape. However, they will rebound to a post-deformation shape shortly after removal of the deformation load. This post-deformation shape will not necessarily be the final shape for the stuffing or filler and it may gradually move closer to its pre-deformation shape and form. The rebound characteristics are not immediate and in some embodiments the rebound characteristics more closely mirror those of natural stuffings or fillers than other artificial stuffings. The stuffings or fillers do not immediately rebound to their post-deformation shape or form. In some embodiments, it can take more than 2, 5, 10 or 20 seconds for the stuffing to reach to its post-deformation state.
The amount of time it takes for the stuffing or filler to reach its post-deformation shape after a deformation load has been removed is defined as the rebound factor. The rebound factor is calculated through use of a nine pound sphere with a ten inch diameter. Approximately 681 g. (1.5 lbs.) of stuffing or filler can be used to fill a standard pillow. The casing for a standard pillow has unfilled dimensions of 20 inches by 26 inches. The standard pillow is placed on a flat surface in the position a pillow is usually placed on a bed for sleeping. The weight is then dropped onto the pillow from a distance of approximately 12 inches above the pillow and approximately immediately raised thereafter. The amount of rebound of the filling or stuffing in the pillow in the vertical direction is measured over several seconds. The rebound factor can is defined as the vertical deformation of the pillow 1 second after the weight is removed minus the vertical deformation of the pillow at the time the weight is applied, with that total calculated amount divided by the vertical deformation of the pillow at approximately 5 seconds after the weight is removed. This quotient is then squared. This formula for the deformation factor is detailed below.
Deformation Factor=(((deform. @1 sec.)−(deform. when weight applied))/deform. at 5 sec)2
In some embodiments, the stuffing has a rebound factor of less than approximately 11.5, preferably less than approximately 3.5 and more preferably less than approximately 2.0.
A test was conducted on a standard pillow that had been stuffed with polyethylene foam pieces with a thickness of approximately 520-540 microns and polyethylene film pieces with a thickness of approximately 17-21 microns. The ratio of polyethylene foam to polyethylene film was approximately 1:3. This stuffing is referred to as “A Stuffing Embodiment” in the table below. These tests revealed that the deformation with the weight applied was approximately −5 cm. One second after the weight was removed, the deformation was approximately −4 cm. 5 seconds after the weight was removed the deformation was approximately −1.9 cm. According to the formula above, the deformation factor for “A Stuffing Embodiment” was calculated as 0.28.
Tests were conducted on standard pillows stuffed with different materials. The results of these tests are shown in the table below.
| ||Deformation ||Deformation ||Deformation ||Rebound |
|Stuffing ||with Weight ||at 1 Second ||at 5 Seconds ||Factor |
|Polyester ball ||−5 cm ||−2.3 cm ||−0.8 cm ||11.39 |
|Feathers ||−5 cm ||−3.5 cm ||−1.1 cm ||1.86 |
|Down ||−5 cm || −4 cm ||−2.1 cm ||0.23 |
|“A Stuffing ||−5 cm || −4 cm ||−2.1 cm ||0.28 |
- Example 1
The following are examples of some of the embodiments of the invention and are offered for purposes of illustration. The examples are not intended to limit the scope of the invention
- Example 2
Polyethylene foam sheets are created using standard foam blowing techniques. The polyethylene foam sheets have a thickness of approximately 390-410 microns or 1/64 of an inch. These foam sheets contain numerous encapsulated or enveloped air bubbles. The polyethylene foam sheets are then subjected to a shearing process. The sheets are fed into a shearing chamber at a rate of approximately 70 ft/min. Shearing instruments in the chamber cut the foam sheets into numerous foam pieces. These foam pieces have a length in the range of approximately 0.5-10 cm. The majority of the foam pieces have a length in the range of approximately 2-4 cm. The polyethylene foam pieces are then used as a stuffing. The foam pieces are placed inside a pillow casing, which is then closed. The resulting pillow is comfortable in use.
- Example 3
Polyethylene foam sheets with a thickness of approximately 360-540 microns are obtained. In addition, polypropylene foam sheets are created using standard foam blowing techniques. The polypropylene sheets include enclosed gas bubbles and have a thickness of approximately 780-800 microns. The polypropylene foam sheets and the polyethylene foam sheets are fed into a shearing chamber simultaneously. The shearing chamber tears the sheets into individual pieces with a length of approximately 1-10 cm. The majority of the individual pieces have length of approximately 2-4 cm. The polypropylene and polyethylene foam pieces are mixed with each other as a stuffing. The polyethylene foam pieces and polypropylene foam pieces are then placed inside a pillow casing in an approximately equal ratio. The pillow casing in then closed to form a pillow.
Polyethylene foam sheets and polypropylene foam sheets, each with encapsulated air are subjected to a shearing process. The polyethylene foam sheets have a thickness of less than approximately 800 micrometers. The polypropylene foam sheets also have a thickness ranging from approximately 360-1600 micrometers. The polyethylene foam sheets and the polypropylene foam sheets are subjected to a shearing chamber. The sheets are placed one on top of the other as they pass through the shearing chamber. After the shearing process, the pieces have a length of approximately 1-6 cm.
- Example 4
The resulting polyethylene and polypropylene pieces make up a stuffing that has a good handfeel. The weight ratio of polypropylene pieces to polyethylene pieces is 1:2. The polyethylene pieces and polypropylene pieces are combined with a polyethylene film that has been subjected to a shearing chamber and does not include encapsulated air. The weight ratio of foam pieces to polyethylene film is 1:1. The foam pieces and polyethylene film are then placed into a synthetic pillow case open on one end. The pillow case is then closed.
Polyethylene foam sheets with a thickness of approximately 520-540 micrometers or 1/48 of an inch are subjected to a shearing chamber. The polyethylene foam sheets contain gas bubbles enveloped in the foam sheets. The polyethylene foam sheets include sheets sold by Polyair under the brand name Starfoam. The gas bubbles are randomly distributed throughout the foam sheets. During the shearing process many of the gas bubbles remain undisturbed. Others of the gas bubbles are pierced and the gas escapes the bubble, leaving behind a three dimensional polyethylene structure.
The polyethylene foam sheets are subjected to a shearing process simultaneously with polyethylene film with a thickness of approximately 17-21 microns. The foam sheets and the film are placed in contact with each other and placed through a shearing chamber at the same time and shredded. The shredded foam and film exit the shearing chamber fully mixed. The weight ratio of polyethylene foam pieces to polyethylene film pieces upon exit of the shearing chamber is approximately 1:2-1:4 and preferably approximately 1:3. The shredded foam and film are placed into a holding area. From the holding area they are fed into pillow cases as stuffing. The pillow cases are then sealed.
- Example 5
The foam and film stuffing exhibits a loft coefficient of approximately 14. Pillows filled with the polyethylene foam and film mix exhibit a rebound factor of approximately 0.28.
Polyethylene foam sheets with a thickness of approximately 520-540 microns and which include encapsulated gas are shredded in a shearing chamber. The shearing chamber shears the foam sheets into individual foam pieces. The resulting foam pieces maintain a thickness of approximately 520-540 microns and have a length of approximately 1 to 6 cm.
- Example 6
The polyethylene foam pieces are placed into a casing and the casing is closed. The foam pieces filled casing can then be used as a pillow.
A polyethylene foam is created in which an antimicrobial is incorporated into the melt stage of the polyethylene. The polyethylene foam has a thickness ranging from approximately 520 to 800 microns. The polyethylene foam contains numerous randomly distributed gas bubbles. The polyethylene foam exhibits a melting temperature of approximately 265-285 degrees Fahrenheit.
A film of polypropylene is obtained. The film has a thickness ranging from approximately 5 to 400 microns. The polypropylene film does not contain gas bubbles and exhibits a melting temperature of approximately 320-350 degrees Fahrenheit.
A film of nylon is obtained with a thickness ranging from approximately 260 to 1600 microns. The nylon film does not contain gas bubbles and exhibits a melting temperature of approximately 425-440 degrees Fahrenheit.
The polyethylene foam, polypropylene film and nylon film are sheared into smaller pieces in a simultaneous process that mixes the pieces into a single stuffing. The resulting pieces have a length of approximately 1-10 cm. The stuffing maintains a general ratio of equal parts of polyethylene foam pieces, polypropylene film pieces and nylon film pieces. The stuffing mixture is then placed into pillow casings or used as a stuffing and/or insulator in jackets, pillows, blankets, comforters, duvets, sleeping bags, mattresses, blankets, cushions and comforters.
Variations and modifications of the foregoing are within the scope of the present invention. It should be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.
Various features of the invention are set forth in the following claims.