Patent Application
20210372691
The present application is directed to liners for appliances, and more particularly materials and methods for forming the liner system.
Appliances, such as refrigeration appliances, conventionally include liners within the cabinet area of the appliance. The interior of the cabinets may have design goals related to aesthetic appearance of the liner. As such, the liners may be colored or have hues or tints, based on consumer desires or aesthetic considerations. The liners are conventionally multi-layer systems produced via extrusion. Conventional liners may require pigments in each independent extruded layer to form a colored liner, resulting in complex and expensive production (e.g., matching layer colors, or pigment cost).
According to one or more embodiments, an appliance liner includes a cap layer including a high-impact polystyrene and a colorant, the cap layer forming an exterior surface of the appliance liner. The appliance liner also includes a polymeric base layer including a high-impact polystyrene and positioned inwardly with respect to the cap layer to provide structural support to the cap layer; and a barrier film positioned inwardly with respect to the cap layer. The barrier film includes silk fibers within a polymer matrix to protect the cap layer from contaminant diffusion and deformation and reduce visible wrinkling in the cap layer during hot insulation filling.
According to at least one embodiment, the polymeric base layer may be positioned between and in contact with the cap layer and the barrier film. In another embodiment, the barrier film may be positioned between and in contact with the cap layer and the polymeric base layer. In one or more embodiments, the silk fibers may be included in the polymer matrix at 2.5 to 15% loading by weight. In at least one embodiment, the silk fibers may have an average length of 10 to 90 mm. In certain embodiments, the polymeric base layer may be a 1170 HIPS material and the cap layer may be a 1115 HIPS material. In at least one embodiment, the polymer matrix may be a thermoplastic polyurethane, a high-impact polystyrene, or both. In further embodiments, the polymer matrix may be a 1115 HIPS material.
According to one or more embodiments, a method of forming an appliance liner includes extruding a mixture of a high-impact polystyrene and a colorant to form a cap layer, and hot-laminating a barrier film including silk fibers dispersed in a polymer matrix with the cap layer to form a composite sheet. The method further includes extruding a high-impact polystyrene base material to form a base sheet, and hot-laminating the base sheet with the composite sheet such that the barrier film is sandwiched between the cap layer and the base sheet to form a laminated appliance liner.
According to at least one embodiment, the silk fibers may be included in the polymer matrix at 2.5 to 15% loading by weight. In one or more embodiments, the polymer matrix may be a thermoplastic polyurethane, a high-impact polystyrene, or both. In some embodiments, the method may further include extruding a bulk material including the silk fibers in a polymer matrix resin to form the barrier film. In at least one embodiment, the silk fibers may have an average length of 10 to 90 mm. In one or more embodiments, the method may further include thermo-forming the laminated appliance liner to form a shaped appliance liner.
According to one or more embodiments, a method of forming an appliance liner includes extruding a first mixture of a high-impact polystyrene and a colorant to form a cap layer; extruding a second mixture of silk fibers dispersed in a polymer matrix to form a barrier film; and extruding a high-impact polystyrene base material to form a base layer. The method further includes joining the cap layer, the barrier film, and the base layer such that the cap layer is an outer layer of the appliance liner and the barrier film is positioned inwardly with respect to the cap layer to protect the cap layer from contaminant diffusion and deformation and reduce visible wrinkling in the cap layer during hot insulation filling.
According to at least one embodiment, the joining may be via tri-extrusion of the cap layer, the barrier film, and the base layer, and one or both of the base layer and the barrier film may include a pigment additive. In other embodiments, the joining may include hot-laminating the cap layer and barrier film to the base layer such that the base layer is between the cap layer and barrier film. In yet other embodiments, the joining may include hot-laminating the cap layer to the barrier film to form a composite sheet. In a further embodiment, the joining may include hot-laminating the composite sheet with the base layer to form the appliance liner. In at least one embodiment, the joining may include hot-laminating the barrier film to the base layer to form a composite base, and hot-laminating the composite base with the cap layer to form the appliance liner.
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
Conventional colored liners may also show scratches or defects in the liner surface where the pigment is incorporated in each extruded layer, causing issues in the aesthetics of the interior cabinet. Furthermore, colored layers of conventional liners may show other defects, such as wrinkling in the various layers, formed during the hot-filling of foam insulation in appliance cavities on an inner side of the conventional liner. Generally, conventional liners include a protective barrier layer on the inner side of the liner to help protect the outer layers. The protective barrier layer prevents hot-filled foam insulation from aggressively attacking the colored layers of the conventional liners. However, the hot-filling may deform or wrinkle the protective barrier layer, the defects and/or wrinkles then being visible in the outer layer when conventional liners, and moreover when the outer layer is pigmented.
According to one or more embodiments, an appliance liner system includes an outer colored cap layer defining an outer surface of the liner, and a barrier film layer including silk fibers for protecting the cap layer from contaminants and/or deformations. The appliance liner system, in certain embodiments, also includes a base layer providing structural integrity to the liner. The barrier film of the appliance liner system advantageously includes the silk fibers within a polymer matrix of thermoplastic polyurethane or high impact polystyrene. This addition of silk fibers to the polymer matrix improves compatibility of the barrier film with the base layer, and also reduces wrinkling in the barrier film that occurs during hot insulation filling, such that any wrinkling would not form or be visible through the cap layer.
In some embodiments, the barrier film is sandwiched between the colored cap layer and the base layer. In such embodiments, the colored cap layer may be the only pigmented layer due to the barrier film reducing the visibility of defects from the base layer in the cap layer and the ability to hot-laminate the barrier film directly to the extruded colored cap layer.
In other embodiments, the base layer is sandwiched between the colored cap layer and the barrier film. In such embodiments, the base layer, barrier film, or both may also include a pigment, with the barrier layer reducing the visibility of defects from the barrier film and base layer in the colored cap layer.
The appliance liner system may be formed by various methods. One such method includes extruding the colored cap layer, hot-laminating the colored cap layer with the barrier film with silk fibers to form a cap and barrier laminate, and hot-laminating the base layer to the cap and barrier laminate to sandwich the barrier layer between the base and cap layers. Another method includes hot-laminating the barrier film with silk fibers with the extruded base layer to form a composite, and then hot-laminating the composite with the colored cap layer to sandwich the base layer therebetween. In another variation, the extruded layers may be hot-laminated together at a single nip-point to form the appliance liner. Yet another method for forming the appliance liner includes tri-extrusion of the layers, with the barrier layer including silk fibers. The appliance liner and the methods of producing the appliance liner will now be discussed in detail.
Referring to
Referring more specifically to
In another embodiment, the appliance liner 200b as shown in
With continued reference to
To form the barrier film 220, the silk fibers 222 are loaded in the polymer matrix 224. The polymer matrix 224 may be a high impact polystyrene (HIPS), a thermoplastic polyurethane, or combinations thereof. In certain embodiments, the polymer matrix 224 is a 1115 HIPS. The barrier film 220 may include, in some embodiments, 2.5 to 15% by weight of silk fibers 222 in the polymer matrix 224, in other embodiments 3 to 12.5% by weight of silk fibers 222 in the polymer matrix 224, and in yet other embodiments, 4 to 10% by weight of silk fibers 222 in the polymer matrix 224. In at least one embodiment, the silk fibers 222 are 5 to 7% by weight in the polymer matrix 224. Furthermore, the silk fibers 222 may be, in some embodiments, 2.5 to 15% by weight of the barrier film 220, in other embodiments 3 to 12.5% by weight of the barrier film 220, in yet other embodiments, 4 to 10% by weight of the barrier film 220. In at least one embodiment, the silk fibers 222 are 5 to 7% by weight of the barrier film 220. The silk fibers may have any suitable length and/or diameter to protect the cap layer 210 from having visible deformations and/or wrinkles, and be present in the polymer matrix at the specified weight. For example, the silk fibers may have, in some embodiments, an average fiber length of 10 to 90 mm, in other embodiments 20 to 80 mm, and in yet other embodiments, 30 to 60 mm. Furthermore, in certain embodiments, the silk fibers may have an average diameter of 5 to 80 μm, in other embodiments, 10 to 60 μm, and in yet other embodiments 15 to 50 μm. Although in the monolayer construction of the overall liner 200 there are no interfaces between the layers, the region of the liner constituting the barrier film 220 may have a thickness in some embodiments of 0.05 to 1.5 mm, in other embodiments 0.1 to 1.25 mm, and in yet other embodiments 0.25 to 0.75 mm. The barrier film 220 may optionally include a colorant or pigment additive to tint the barrier layer, in embodiments where, for example, tri-extrusion is used.
With respect to the cap layer 210, the cap layer 210 may comprise any suitable polymeric material meeting the desired aesthetics of the interior of the appliance cabinet 120. In one or more embodiments, the cap layer 210 is a high-impact polystyrene (HIPS) material. More particularly, the HIPS is a 1115 HIPS. The HIPS material may be classified by a numeral, such as, but not limited to, 1115 HIPS or 1170 HIPS, which refers to the polymer quality of the resin, with 1115 HIPS being shinier and glossier than the 1170 HIPS. Although in the monolayer construction of the overall liner 200 there are no interfaces between the layers, the region of the liner 200 constituting the cap layer 210 may have a thickness in some embodiments of 0.05 to 1.5 mm, in other embodiments 0.1 to 1.25 mm, and in yet other embodiments 0.25 to 0.75 mm.
As the cap layer 210 is generally visible in the interior cabinet 120, the cap layer 210 further includes a colorant or pigment additive (hereinafter referred to interchangeably) mixed with the high-impact polystyrene. The concentration of colorant including in the cap layer 210 may be any suitable amount sufficient for the liner 200 to have the aesthetically desired color, hue, or tinting. In certain embodiments, the colorant may be at a concentration of 2.5 to 50% by weight of the cap layer, in other embodiments, 5 to 40%, and in yet other embodiments 7 to 25%. The barrier film 220 and/or the base layer 230 may optionally include a colorant or pigment additive to tint the barrier layer and/or the base layer 230, respectively, which may aid in reducing the visibility of any defects from the formation of the liner 200 from showing through the coloration of the cap layer 210. The colorant ma be included in base layer 230 and/or barrier film 220 at similar concentrations to the cap layer 210.
With respect to the base layer 230, the base layer 230 may comprise any suitable polymeric material meeting the desired structural integrity to the liner 200. In one or more embodiments, the base layer 230 is a high-impact polystyrene (HIPS) material. More particularly, the HIPS is a 1170 HIPS. Although other HIPS material may be incorporated, 1170 HIPS is a glossier and shinier HIPS than 1115 HIPS, as previously noted. Although in the monolayer construction of the overall liner 200 there are no interfaces between the layers, the region of the liner 200 constituting the base layer 230 may have a thickness in some embodiments of 0.05 to 1.5 mm, in other embodiments 0.1 to 1.25 mm, and in yet other embodiments 0.25 to 0.75 mm. The base layer 230 may optionally include a colorant or pigment additive to tint the base layer 230, in embodiments where, for example, tri-extrusion is used.
Referring to
Referring to
By incorporating the above methods and the silk-fiber barrier film, only the cap layer in certain embodiments requires inclusion of the colorant. Via the hot-lamination processing, dilution of the pigment and mixing issues between the layers is avoided, and the colorant remains visible in the cap layer after joining with the barrier film and/or base layer. However, the appliance liners with a silk fiber barrier layer may also be formed using other methods such as, but not limited to, tri-extrusion (not shown), with colorant added to each layers feed polymer.
According to one or more embodiments, an appliance liner system includes an outer colored cap layer and a barrier film layer. The barrier film of the appliance liner system includes silk fibers within a polymer matrix of thermoplastic polyurethane or high impact polystyrene reduce wrinkling in the barrier film such that wrinkling is not visible in the cap layer. Furthermore, the appliance liner may include a polymeric base layer for providing structural support to the liner. The silk fibers of the barrier film further improve compatibility of the barrier film with the base layer. In certain embodiments, the barrier film is sandwiched between the cap layer and the base layer, and in other embodiments the base layer is sandwiched between the cap layer and the barrier film. The barrier film is positioned on the inner side of the colored cap layer to protect the cap layer from contaminants and/or deformations during insulation filling for the appliance. The appliance liner may be extruded as a monolayer including the extruded cap layer, barrier film, and base layer, or be separately extruded such that the layers are hot-laminated together. In certain embodiments, the barrier film is hot laminated with the cap layer to form a composite sheet, which is then hot-laminated with the base layer. In other embodiments, the barrier film may be hot-laminated with an extruded base layer and subsequently hot-laminated with an extruded cap layer. As such, an appliance liner with silk fibers in the barrier film provides improvements in the aesthetic appearance on the surface of the outer cap layer.
Except where otherwise expressly indicated, all numerical quantities in this disclosure are to be understood as modified by the word “about” in describing the broader scope of this disclosure. Practice within the numerical limits stated is generally preferred. Also, unless expressly stated to the contrary, the description of a group or class of materials by suitable or preferred for a given purpose in connection with the disclosure implies that mixtures of any two or more members of the group or class may be equally suitable or preferred. Furthermore, practice within the numerical limits stated is generally preferred.
Additionally, unless expressly stated to the contrary: the term “polymer” includes “oligomer,” “copolymer,” “terpolymer,” and the like; molecular weights provided for any polymers refers to weight average molecular weight unless otherwise indicated; the description of a group or class of materials as suitable or preferred for a given purpose in connection with the invention implies that mixtures of any two or more of the members of the group or class are equally suitable or preferred; description of constituents in chemical terms refers to the constituents at the time of addition to any combination specified in the description, and does not necessarily preclude chemical interactions among the constituents of a mixture once mixed; the first definition of an acronym or other abbreviation applies to all subsequent uses herein of the same abbreviation and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation; and, unless expressly stated to the contrary, measurement of a property is determined by the same technique as previously or later referenced for the same property.
It is also to be understood that this invention is not limited to the specific embodiments and methods described below, as specific components and/or conditions may, of course, vary. Furthermore, the terminology used herein is used only for the purpose of describing particular embodiments of the present invention and is not intended to be limiting in any way.
It must also be noted that, as used in the specification and the appended claims, the singular form “a,” “an,” and “the” comprise plural referents unless the context clearly indicates otherwise. For example, reference to a component in the singular is intended to comprise a plurality of components.
The term “comprising” is synonymous with “including,” “having,” “containing,” or “characterized by.” These terms are inclusive and open-ended and do not exclude additional, unrecited elements or method steps.
It should also be appreciated that integer ranges explicitly include all intervening integers. For example, the integer range 1-10 explicitly includes 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Similarly, the range 1 to 100 includes 1, 2, 3, 4, . . . 97, 98, 99, 100. Similarly, when any range is called for, intervening numbers that are increments of the difference between the upper limit and the lower limit divided by 10 can be taken as alternative upper or lower limits. For example, if the range is 1.1. to 2.1 the following numbers 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 can be selected as lower or upper limits. In the specific examples set forth herein, thickness, concentrations, temperature, and reaction conditions (e.g. pressure, pH, etc.) can be practiced with plus or minus 50 percent of the values indicated rounded to three significant figures. In a refinement, concentrations, temperature, and reaction conditions (e.g., pressure, pH, etc.) can be practiced with plus or minus 30 percent of the values indicated rounded to three significant figures of the value provided in the examples. In another refinement, concentrations, temperature, and reaction conditions (e.g., pH, etc.) can be practiced with plus or minus 10 percent of the values indicated rounded to three significant figures of the value provided in the examples.
In the examples set forth herein, concentrations, temperature, and reaction conditions (e.g., pressure, pH, flow rates, etc.) can be practiced with plus or minus 50 percent of the values indicated rounded to or truncated to two significant figures of the value provided in the examples. In a refinement, concentrations, temperature, and reaction conditions (e.g., pressure, pH, flow rates, etc.) can be practiced with plus or minus 30 percent of the values indicated rounded to or truncated to two significant figures of the value provided in the examples. In another refinement, concentrations, temperature, and reaction conditions (e.g., pressure, pH, flow rates, etc.) can be practiced with plus or minus 10 percent of the values indicated rounded to or truncated to two significant figures of the value provided in the examples.
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.
