The present invention relates to a foam mat and method for manufacturing a foam mat.

[STATE OF THE ART]

In many cases, sheets of virgin foam are trimmed at the edges to create a size and shape for a product, and the trimmed edges are discarded or recycled to produce rebonded foam such as is typically used for carpet padding. These sheets of virgin foam typically have a consistent and specific density that may not be useful in making carpet padding.

Simultaneously, foam mats, as are typically used in kitchens, bathrooms, and workstations, have been made from virgin foam of a density desirable for each specific type of mat. Heretofore, the inconsistent nature of the rebond has not provided an acceptable feel and desired comfort for the mats so has not been used.

Additionally, closed-cell foam has not been a desired product to use in mats that are expected to be washable. Closed-cell foam, frequently called “memory foam” does not dry as quickly as open-cell foam. Purchasers and users of mats expect that foam mats may be washed in a household washing machine and may be dried in an expected time. However, closed-cell foam takes considerably longer to dry in a household dryer, which is not desired.

To this aim, the invention relates to a foam mat and a method as defined in the appended independent claims, wherein preferred embodiments are defined in the dependent claims.

In a first independent aspect, the invention relates to a mat comprising: a cushion layer comprising a thickness, a top side, a bottom side, and wherein the top side is bonded to a fabric layer; the cushion layer comprising a foam sheet having a first density; and wherein the foam sheet is comprised of a plurality of foam particles having a first range of sizes and a first range of densities.

In a second independent aspect, the invention relates to a mat comprising: a cushion layer comprising a thickness, a top side, a bottom side, and wherein the top side is bonded to a fabric layer; wherein the cushion layer has a first density and comprises a first plurality of foam particles of a second density bonded together; and wherein the first density is greater than the second density.

Additionally, in a third independent aspect, the method of forming a mat comprises: milling at least one segment of foam having a first density to form a plurality of foam particles, wherein the particles of foam have sizes in a first size range of between 1mm and 15mms; mixing the plurality of particles with glue; applying heat and compression to the plurality of foam particles mixed with glue to form a body of foam having a second density, wherein the second density is greater than the first density; cutting a portion of the body of foam to form a cushion having a first side, a second side, and a thickness; and adhering a fabric layer to the first side.

In many applications, a large cylinder of virgin foam may be formed at a specific density. The cylinder of foam may then be axially sheared by a blade to remove specific thicknesses of foam that may then be used in making foam-based products. For example, the foam may be cut into pillows, cushions, mats, and other products. In making most of these products some of the edges may be cut away to provide a crisp, clean edge. The edge pieces have typically been discarded and/or used to make rebond.

Lighter density edge pieces may not be suitable for making rebonded foam to be used as carpet padding. Lighter foam such as this may have a density in the range of 10 to 40 kilograms per cubic meter, with an average of between 20 and 30 kilograms per cubic meter. In this form, this foam is also not suitable for use in making mats, since the densities of foam used for mats is between 60 and 80 kilograms per cubic meter for bathmats, and between 100 and 160 kilograms per cubic meter for kitchen mats. Mats used for other applications, such as workstation mats, may extend across those ranges to be between 40 and 200 kilograms per cubic meter. Applicants have invented methods to form this lighter density foam into a new foam product with configured densities that may be used in many different applications. This disclosure exemplifies bath and kitchen mats as exemplary embodiments. However, those of ordinary skill in the art in possession of the teachings herein will recognize that the inventions disclosed herein may be applied in many other embodiments.

If virgin foam or discarded portions of virgin foam is to be used, it is first shredded into particles. Applicant has found that common shredding methods may be employed that will produce irregularly shaped particles. This means that upon examination, the particles may appear to be roughly spherical, but may have some irregularities from being truly spherical. Such irregularities may include surfaces that are flat and surfaces that have projections. Applicant has found that minor irregularities such as these may provide more surface area for bonding than would be provided with truly spherical particles.

In addition to shredding, Applicant has found that cutting pieces of foam into cubes or cuboids. Applicant expects that other shapes such as pyramids, prisms, and cylinders will also be acceptable shapes useful in the inventions disclosed and taught herein. However, since shredding may be easier to accomplish, and provides, acceptable results, the examples used within this specification will, without limit, be for shredded foam of roughly spherical shapes.

Lighter density foam pieces that that Applicant has used in the inventions disclosed and taught herein have been of the density of between of 10 to 40 kilograms per cubic meter, with the majority of discarded foam having densities of between 20 and 30 kilograms per cubic meter. In the art, densities of foam are usually expressed where “kilograms per cubic meter” are described as “D”. Therefore, 30D foam has a density of 30 kilograms per cubic meter. As will be apparent to those skilled in the art and in possession of the inventions disclosed herein, other densities of foam may be used to produce foam articles of configurable densities for many uses. Applicant has found that most people prefer a lower density foam for bathmats and a higher density foam for kitchen mats. Bathmats typically have a density of between about 60D and 80D, which is considered to be “soft”. Kitchen mats typically have a density of between about 100D and 180D, which is considered to be “hard”. Workstation mats may have densities of between 40D and 200D.

Additional envisioned embodiments include the use of particles of shredded rebonded foam. In most cases, rebonded foam has a density of between 95D to over 100D.

In the embodiment of making foam for bath and kitchen mats, shredding the foam should yield a range of particle sizes of between 1 millimeter (mm) and 15mms as they are measured across. If the particles were actually spheres, this would mean that the particles would have diameters of between 1 and 15mms. Several different methods may be employed to ensure that only particles of between 1mm and 15mms are used, Applicant has found satisfactory results using progressive sieves.

If particles in the full range of l-15mms are to be used, then a sieve having openings of 15mms across may be used. This will allow particles having sizes of up to 15mms across to pass through the sieve. Those of skill in the art will recognize that some particles smaller than 1mm across will also pass through the sieve. In normal shredders, there are generally few of those and their inclusion in the rest of the process has not been found to present any difficulties. Those skilled in the art will also recognize that particles greater than 15mm across may also pass through the sieve. This may happen if a particle is roughly ellipsoidal with a minor axis of 15mms or less and a major axis of 15mms or more, then it may go through the sieve along its minor axis. Applicants have found that having some particles of greater than 15mms has not presented any difficulties in the processes and articles disclosed herein. In this exemplary process, particles having a size greater than 15mms may be gathered and sent back into the shredder so the resulting particles will have sizes less than 15mms.

Some portions of the foam particles may be captured for specific use. For example, particles having a range of 1mm to 8mms may be captured as one portion, and particles having a range of 8mms to 15mms may be captured as a second portion. Those familiar with the art will understand that different sieves may be used to gather these portions.

Once a desirable portion of sized particles has been gathered, the particles may be mixed with glue and pressed together into a single body. While any shape may be utilized for the inventions disclosed and taught herein, Applicant has found that shaping the body into a cylinder may be beneficial to the process of utilizing the body of foam for making mats.

In pressing the foam particles together with glue, a specific density may be obtained. For example, a forming cylinder may be used to form the foam body. This cylinder may be closed at one end and have a lid that may tightly fit into the open end. A specific weight of the particles and glue mixture may be weighed into the cylinder and the lid pressed down upon the mixture until a specific volume is reached, thereby producing a body with a known density. Once the glue has set, the body may be released from the cylinder without changing its volume. That is to say that the foam body does not expand by any substantial amount after being released from the form.

In one of many embodiments, high pressure and temperature may be used to set the glue and particles to a desired volume for a given weight of particles. In one of many embodiments that those of ordinary skill in the art may envision when in possession of the teachings and disclosures disclosed herein, the temperature of the foam particles and the glue may be at ambient room temperature when they are loaded into the cylinder. The cylinder and the contents may be kept at that temperature. In alternate embodiments, the glue may be a heat-settable glue and the temperature controlled in such a way as to set and/or cure the glue when in the cylinder. Similarly, a greater pressure may be applied to force the foam particles to compress while the glue is setting. In this way, once the glue has set, the foam particles may remain in a compressed state even after the formed body is removed from the forming cylinder.

While the entire range of foam particles may be used in manufacturing a body of foam, Applicant has found it to be advantageous to utilize the foam particles of a particular size to better form a body into a desired and configurable density. Applicant has found that using smaller particles, such as those between 1mm and 8mms, will take less pressure in the cylinder to make a higher density foam body, and larger particles, such as those between 8mms and 15mms will take less pressure in the cylinder to make a lower density foam body. That is to say that using particles of about between 1 and 8mms will be used to make a foam body of between about 100D and 180D, which may be used to make kitchen mats. On the other hand, using particles of about between 8mms and 15mms will be used to make a foam body of between about 60D and 80D, which may be used to make bathmats

While the examples of making bath and kitchen mats described approximations of resulting densities, those of ordinary skill in the art and in possession of the inventions disclosed herein will be aware that the processes disclosed herein may be used to make very precise foam bodies. For example, a group of particles of foam of between 1 and 8mms may be formed into a foam body of precisely any density between 100D and 160D with a small variance.

In a preferred embodiment, an oil-based glue or adhesive may be used. This may be preferable to using latex or other water-based glues in the production of mats that are expected to be exposed to water in their use, such as bath and kitchen mats. However, in other embodiments, latex or other water-based glues may be used without departing from the scope of the inventions disclosed and taught herein.

The foam particles and the glue may be mixed before being loaded into the forming cylinder, or they may be mixed while in the forming cylinder. The intent of the mixing is to ensure that the foam particles are coated to a sufficient degree, so they adhere to adjacent foam particles. Before mixing, or even during mixing, additives such as antimicrobials, color additives, fire retardants, and/or any other additive known to those ordinarily skilled in the art, may be added to the mix.

The selection of a cylinder for the form of the body of foam allows it to be sheared into a long pad similar to the way that cylinders of virgin foam are sheared. That is to say that the cylinder may be axially rotated with a blade at a radial distance from the center and the blade advanced towards the center as the cylinder rotates. This will produce a long sheet of foam of uniform thickness.

In another embodiment of the inventions taught and disclosed herein, sections of foam produced through the methods disclosed herein may be bonded together to form a mat. In this, slices of foam of approximate lengths of 10-50mm, with cross-section areas of the foam strips of l-50mm ² may be bonded together to form a mat.

This sheet of foam may be cut like any other sheet of foam to an appropriate size, such as for a bath or kitchen mat. A pile may be added to a top side. Fabric may be secured between the pile and the sheet as well if it is desired. On the bottom of the sheet, an antiskid mat may be secured. Similarly, a piece of fabric may be secured between the antiskid mat and the foam. Applicant has found that a piece of fabric bonded between the foam and either or both of the pile and antiskid mat may form a better bond and prevent glue from seeping. For instance, in some loose piles the glue may rise up into the individual strands when pressed together with the foam. A layer of fabric will prevent that seepage, which may be uncomfortable to walk upon.

The washability of the produced mat is another of many aspects of the inventions disclosed and taught herein. Mats made from open cell foam have a desirable quality that they may be washed and dried in common household appliances such as a washer and dryer. Typical users have an expectation that mats may be dried in a dryer within a normal dryer run time, which is usually around an hour. Mats made with virgin open cell foams adhere to this expectation. However, mats made with closed cell foams usually take more than 1.5 to 2 hours in a common household dryer to dry. Applicants have found that a mat made from the inventions disclosed and taught herein take on the characteristics of virgin open cell foam and may be dried in common household dryers in the same time as mats made with virgin open cell foam.

This does not preclude the use of closed cell foam in the manufacture of the foam as disclosed and taught herein. Applicant has found that some amounts of closed cell foam may be shredded as described herein and mixed with some amounts of open cell foam before being mixed with glue and pressed into a body. The resulting foam sheets maintain the characteristics of open cell foam in their softness/hardness, washability, and dry ability.

Applicant has also found that the foam produced through the processes and methods disclosed herein are further recyclable. This foam may be utilized in making rebonded foam, or used again in the processes and methods disclosed and taught herein.

With the intention of better showing the characteristics of the invention, herein after, as an example without any limitative character, some preferred embodiments are described, with reference to the accompanying drawings, wherein:

Figure 1 represents a foam mat according to the inventions disclosed and taught herein;

Figure 2 represents a cross-section according to line II-II in Figure 1;

Figure 3 represents one of many possible configurations for a mesh cloth;

Figure 4 represents one of many possible configures for an antiskid layer; and Figure 5 represents a method according to the inventions which may be applied for manufacturing the foam mat of Figure 1.

Figure 1 represents a foam mat 100 according to the invention. A pile 10 may be seen to cover the top and sides of the mat 100. This pile 10 may be of any material suitable for use. For example, and without limitation, a bathmat may have a soft pile that may be more comfortable for bare feet, while a kitchen mat may have a short pile or a simple fabric that wears well for being stood upon with shoes.

Figure 2 represents a cross-section 200 according to line II-II in Figure 1. The pile 10 covers a fabric layer 20, which in turn covers a foam layer 50. Foam layer 50 sits upon an antiskid layer 40. The overall height of the foam layer 50 may be between 5 and 30 millimeters, which is typical for bath and kitchen mats.

It should be known that the fabric layer 20 is optional, and that another optional fabric layer (not shown in the figures) may be secured between the foam layer 50 and the antiskid layer 40.

Foam layer 50 is comprised of foam particles 30, which may be of a size of between 1 and 15mms. In a first embodiment, they may be of a size of between 1 and 8mms. In another embodiment, they may be of a size of between 8 and 15mms. Other embodiments may use other size ranges.

An antiskid mat 40 may be secured to the bottom of the mat 100 using PVC glue or any other suitable bonding substance. The antiskid mat 40 may be a single sheet, or it may have perforations or be made in the form of a mesh with open areas. Making the antiskid mat 40 in the form of a mesh reduces the overall weight of the foam mat 100. It may also provide more open spaces that may allow water and water vapor to exit the foam mat 100 while it is being dried.

The antiskid mat 40 may be made of polyester or any other material suitable for preventing the foam mat 100 from sliding on surfaces such as floors. In some cases, it may be preferable to have a mesh cloth bonded to the bottom of the foam mat 100, and then have an antiskid mat 40 bonded to the mesh cloth.

Similarly, the pile 10 and fabric layer 20 may be secured with PVC glue or any other suitable bonding substance. The pile 10 and fabric layer 20 may be secured to the foam layer 50 in such a way as to permit the flow of air into and out of the foam layer 50. This may further promote drying of the mat 100 in both ambient conditions and when in a dryer.

The foam particles 30 may be of the sizes and shapes disclosed herein and may be secured together in the manners disclosed herein. As disclosed these particles may be produced from foam sheets having densities of between 10D and 40D for the production of bath and kitchen mats, but may be made from foam of any density for other applications.

Applicant has found that pressing the foam particles 30 together as disclosed herein may still leave some interstitial gaps (not identified in this figure) between the foam particles 30. These interstitial voids may be regarded as flow passages between open cell foam particles that may further aid in allowing water and water vapor to be removed from the foam mat 100 by squeezing and/or drying.

As shown in Figure 3, a mesh cloth 300 of the anti-slip layer may include a plurality of parallel arranged warp lines 311, with a plurality of rectangular frame lines 312 distributed along the length direction of the warp line, and each edge corner of the rectangular frame line 312 and the warp line 311 may be connected by oblique lines 313. The spacing between the adjacent warp lines 311 may be between lOmms and 15mms, and the rectangular area of a single rectangular frame line 312 may be between 15mm ² and 50mm ² . One of many beneficial effects of adopting this, or a similar format may be to improve the uniformity of the anti-slip layer distribution and improve the uniformity of the PVC hanging slurry on the mesh cloth 300 while adhering the antiskid layer 40 to the foam mat 100.

Figure 4 represents one of many possible configures for an antiskid layer 400 that may be used in the inventions disclosed and taught herein. As may be seen by those of skill in the art and in possession of the inventions taught and disclosed herein, this antiskid layer 400 may be configured to be applied directly to the bottom of the foam mat 100, or over a mesh cloth 300. This exemplary antiskid layer 400 has openings 430 that may be configured to align with the openings of the mesh cloth 300. Figure 5 represents one of many possible methods according to the inventions disclosed and taught herein, which may be applied for manufacturing the foam mat 100 of Figure 1.

In a first step 510, segments of foam are gathered and milled to form a plurality of foam particles. The step of milling the foam may be of shredding, cutting, or otherwise manipulating the foam to produce particles. Generally, this step involves the operation of: mill at least one segment of foam to form a plurality of foam particles.

In the second step 520, the particles of foam are mixed with glue. The particles of foam may be all of the foam produced from the first step 510, or a subset of the particles that have a range of sizes. Generali, this step involves the operation of: mix the plurality of foam particles with glue. This step may be performed in a separate mixing chamber, or directly in a forming chamber.

The third step 530 applies pressure and a temperature to the mixture of glue and foam particles within a form. One form may be a cylinder while another may be a box. In any container, a specific weight of the mixture of glue and particles is compressed to a specific volume to produce a foam body having a density. Generally, this step involves the operation of: apply heat and compression to the plurality of foam particles mixed with glue to form a body of foam.

In the fourth step 540, the body of foam is cut into shapes that may be used to produce mats or other articles. Generally, this step involves the operation of: cut a portion of the body of foam to form a cushion.

In the fifth step 550, at least one fabric layer is adhered to the piece of foam to produce a mat. This fabric layer may be a pile. Additionally, an antiskid mat may be secured to the bottom of the mat. Generally, this step involves the operation of: adhere a fabric layer to the top of the body of foam. The present invention is in no way limited to the herein above-described embodiments, on the contrary may such floor panels and methods be realized according to various variants, without leaving the scope of the present invention.