One-piece foam frame for mounting screen and/or screen stencil film to create screens for manual and small off-contact printing substrates

Abstract

A portable one-piece foam frame for use in securing a screen and/or screen stencil film for use in an off-contact stenciling operation. The assembly includes a paper or release covering an adhesive on one side of the frame. A non-skid coating may be applied to the base of the frame to keep it from shifting or moving during a stenciling operation.

Claims

1. A stencil assembly for screen printing an image on a substrate, said stencil assembly comprising: a one-piece compressible foam frame having a substrate side for contacting the substrate and a screen side opposite the substrate side, the screen side being spaced from the substrate side by a predetermined distance when the foam frame is in an uncompressed condition, said foam frame having an inner perimeter defining a central opening of the foam frame and an outer perimeter surrounding the inner perimeter; and a screen stencil attached to the screen side of the foam frame outside the inner perimeter so the screen stencil covers the central opening; wherein when the foam frame is oriented so the substrate side faces downward and the foam frame is positioned so the substrate side contacts an upward-facing planar surface, the screen stencil is spaced from the planar surface; wherein when the foam frame is positioned so the substrate side contacts the upward-facing planar surface and a distributed load is applied downward on the screen stencil by an edge of a squeegee, the assembly deforms so the screen stencil contacts the substrate along a line having a length equivalent to that of the edge of the squeegee; and wherein when the foam frame is positioned so the substrate side contacts the upward-facing planar surface and the distributed load is removed from the screen stencil, the assembly returns to an undeformed shape so the screen stencil is spaced from the planar surface.

2. A stencil assembly as set forth in claim 1, wherein the foam frame has a stiffness sufficient to stand upright on an end of the foam frame under a combined weight of the foam frame and the screen stencil for storing and drying the assembly.

3. A stencil assembly as set forth in claim 1, wherein the compressible foam frame and screen stencil are insoluble in water thereby permitting cleaning with water.

4. A stencil assembly as set forth in claim 1, wherein the substrate side of the foam frame comprises a non-skid surface.

5. A stencil assembly as set forth in claim 1, wherein the foam frame has a thickness less than about inch.

6. A stencil assembly as set forth in claim 5, wherein the foam frame has a thickness of at least about inch.

7. A stencil assembly as set forth in claim 1, wherein the foam frame has a thickness of at least about inch.

8. A stencil assembly as set forth in claim 1, wherein the foam frame comprises a foam having an Indentation Load Deflection (ILD) rating in a range from about 1.9 to about 3.1.

9. A stencil assembly as set forth in claim 1, wherein the planar surface against which the substrate side is positioned is level.

10. A stencil assembly as set forth in claim 1, wherein the screen stencil provides an off-contact distance of at least about inch.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In referring to the drawings,

(2) FIG. 1 shows a foam frame with adhesive covered with a paper or other release sheet before usage;

(3) FIG. 2 shows the paper adhesive covering of the release sheet being peeled and discarded;

(4) FIG. 3 shows the adhesive side of foam frame being applied to back side of dry screen film or a dry screen stencil;

(5) FIG. 4 is an isometric view of foam frame with screen stencil correctly oriented upright before usage;

(6) FIG. 5 shows the frame on a substrate and in use;

(7) FIG. 6 shows the frame with off contact or snap, or shirt, etc.;

(8) FIG. 7 shows the frame being removed from substrate after application of a print.

(9) FIG. 8 shows the ease with which a stencil can be rinsed when mounted in the frame;

(10) FIG. 9 shows the frames drying in a flat and stretched state and easily stacked together for space efficiency during storage; and

(11) FIG. 10 shows prior art where screen stencils have no frame and are laid out to dry and curl.

DESCRIPTION OF THE PREFERRED EMBODIMENT

(12) The present invention will now be described in its structural detail, and in terms of the preferred embodiment. This embodiment, and any modifications, are set forth to aid in the depiction and illustration of the present invention, but are not to be construed as limiting. Throughout the application where the stenciling film is identified as a mesh, mesh stencil, mesh means, screen or screen stencil, generally these are all identified through the use of the term screen or screen stencil. In addition, throughout the application where the stenciling function takes place upon a substrate, that substrate can include any type of fabric, such as clothing, like a shirt, hat, socks, or any other item of clothing, in addition to upholstery, for example, upon chairs or other furniture, and can also include the stenciling upon paper, foam, glass, metal, wood or any other type of structure upon which stenciling may be applied.

(13) In referring to the drawings and particularly FIG. 1, the invention is depicted as a portable one-piece frame 1 usable with screens or screen stencil film 2, as noted in FIGS. 3 and 4, to create screens for printing off-contact, upon any substrate, such as fabric, paper, glass, metal, wood or any other materials that normally can be printed through the stenciling method. The preferred material for the frame will generally be of a polymer material having some resiliency, such as polyurethane, polyethylene, polystyrene, polypropylene, or any other material to provide a low cost, light weight, but water-friendly user form of structure, as can be seen. The shape and size of the frames may vary depending upon the dimensions of the mesh stencil film to be used with it, but typically, the frames will be of a rectangular design with exterior dimensions of approximately 4.25 inches by 5.5 inches, or 5.5 inches by 8.5 inches, or 8.5 inches11 inches to allow for a very ease of portable usage, but obviously, could be of any other size and/or shape, such as circular, round, rectangular, oval, square, hexagonal, triangular, etc., as may be preferred for a given stenciling operation. For example, the concept of this invention can even be used with a frame that may have overall exterior dimensions within the vicinity of 16 inches to 24 inches, and yet be constructed in the manner as described for the invention herein, and have the various dimensional parameters, such as the offset above the substrate being printed, to those dimensions as described herein. Additionally, the width of the frame border may vary but may possibly be between inch to 1 inches, depending on the overall size of the frame, noting that smaller frames will necessitate thinner frame borders while larger frames may necessitate wider frame borders. The same can be said with respect to the thickness of the frame what may be inch to as much as inch more or less, and which may be appropriate for the structure.

(14) FIG. 1 shows the frame 1 itself, with the paper or other release material 3 applied thereon, on its upper surface, where the upper surface of the foamed frame material includes an adhesive coating, as at 4, as can be noted in FIG. 3. This is the way the framed material may be marketed in a kit, readied for usage and application by the user.

(15) FIG. 4 depicts the front elevational view of the one-piece frame 1 with the thickness and orientation of the foam frame as the focus. Generally, the frame thickness of the present invention may be somewhere in the vicinity of to , more or less for smaller sized frames, and up to 1 inch and beyond for larger sized frames but not limited to these measurements, as clearly the measurements will be determined according to the size of the frame and materials used, as previously described. Additionally, the orientation of the frame when prepared is noted in FIG. 3, and when used is flipped upside down, as noted in FIG. 4, as opposed to prior art and traditional screen printing methods. Therefore, the squeegee side of the frame is directed to be the flat upper side of the frame, and the substrate side or lower side of the frame is directed to be noted in FIG. 3, completely contrary to all prior forms of this art. Due to the frame's thickness and squeegee side orientation, the actual frame functions to provide an off-contact manner for printing. Additionally, the nature of the foam frame acts to assist with the snap while printing so that the peel rate is sufficient.

(16) FIG. 2 depicts the released paper adhesive covering 3 being peeled thus exposing the adhesive material which coats one side of the frame. The preferred adhesive will be strong enough for semi permanent mounting of the screen stencil. This adhesive will most likely be a high performance, pressure sensitive adhesive, for semi permanent mounting of the screen stencil. The adhesive will most likely be based on an elastomer and may or may not be compounded with a tackifier. In addition, when water is applied for cleaning purposes, the adhesive will not interact with applied water so as to lose its strength or hold of the screen stencil and will not wash and subsequently harden onto the screen thus blocking and ruining the open areas of the screen stencil. The preferred adhesive will most likely be a high performance, pressure sensitive adhesive, for semi permanent mounting of the screen stencil. The adhesive will most likely be based on an elastomeric and may or may not be compounded with a tackifier, as previously reviewed.

(17) Additionally, the bottom surface of the foam frame which rests on the substrate, as depicted in FIG. 4, may or may not have a non-skid material such as rubber or plastic applied or inherent in the frame so that when the frame is in use, there is high resistance to skidding or slippage across the substrate, such as a shirt, therefore adequately holding the frame in its place while in use to achieve a sharp image.

(18) The purpose of the foam frame is to provide for an off-contact distance between the frame and the substrate being printed. When a ink-filled screen, such as the one previously identified, is set upon a fresh substrate, generally, such ink will not be deposited onto the screen until it is accurately positioned. This can be seen in FIGS. 5 and 6. Once positioned precisely, and pressure is applied manually to the frame, or pressure is applied to the screen containing the ink through the use of a squeegee or blade 5, as noted in the FIG. 5, and the nature of the foam material forming the frame allows the frame to give slightly, so that the ink is printed onto the substrate below. When no more pressure is being applied, the foam frame allows the screen to snap back to a height above the substrate, leaving a crisp image below, and one that has little to no more contact with the substrate, and therefore, smudging will not occur. See FIG. 6. The desired steady state space between the screen stencil and the substrates being printed may be a fraction of an inch, such as 1/16, , or etc., as may be required.

(19) As previously summarized, there is the potential for modifications to this invention where the density of the foamed polymer may be within the range of approximately one to four pounds per cubic foot, where the foamed polymer is a polyurethane, or approximately within a range of one to nine pounds per cubic foot, where the foamed polymer is a polyethylene polymer. Where a softer polymer foam is used, the bottom surface of the frame will have sufficient frictional contact with the substrate to be printed, to hold the frame in place, and the top surface of the frame may have sufficient frictional engagement with the stencil, to also hold it elevated in place, during a stenciling operation, but yet be able to allow the stencil screen to snap upwardly, in an off-contact manner, after the stenciling operation, to assure a clean and crisp image has been applied. In addition, it is also likely that the stencil screen itself, when formed of plastic+6, may be formed with an integral bead around its lower surface, or that surface forming the well and in proximity with the substrate to be imprinted, and that bead will act as a frame for holding the stencil upwardly, in its desired off-contact manner, and be marketed in that condition, ready for application and usage by the consumer, when preparing for a stenciling operation. These are just examples of how the simple concept of this invention may be obtained for forming the one-piece frame and mounting screen for achieving the stenciling operations of this invention. Under such circumstances, the integral bead as partially shown at 6, forming the frame for the stencil may be of a denser polymer, and perhaps can even be molded in place with the screen, when prepared. In addition, it is likely that the stencil screen itself may have an adhesive or tack applied around its underside perimeter, and have the release material applied thereto, so that when it is peeled free, it can be adhered to the upper surface of the foamed frame, readying in the stencil for usage for printing an image or other indicia upon a substrate.

(20) To give an indication of the range of density for such foam, usually, density is measured under the ILD ratings of such foam material. The ILD ratings generally determine the density of the foam. A rating of 1.8 is usually defined as an extra soft foam. A rating of 2.7 is considered a medium density, while a rating of 3.0 is considered an extra firm rating. The for the current invention, and ILD rating of from medium to firm, such as 1.9 to 2.8, will provide a textured foam having a density that can resist pressure, as applied when stenciling, and allow the frame to support the stencil screen during its usage, and maintain it off-contact from the surface of the cloth or sheet being stenciled during a stenciling procedure. In actuality, a density of about 2.8 should usually be sufficient.

(21) FIG. 7 shows the frame 1 with its screen 2 being elevated from the substrate S to which the screen print has been previously applied, as noted. FIG. 8 shows the ease at which the stencil can be rinsed, with water, and a brush, even when mounted to its frame 1. FIG. 9 shows how a series of the stencil screens, adhere to their frames, may be stacked flat, and will not adhere to each other, since the screens are separated, as can be noted. Finally, FIG. 10 shows how with prior art type of screens, they can not only stick to each other, but they curl up when drying, and take up space, as when not in usage. Hence, this shows the desirable aspects of the framed stencils, as noted in FIG. 9, and how they can be much more easily handled, during and after usage.

(22) As can be readily recognized from reviewing the concept of this current invention, it is a hand held type of portable stenciling device that can be applied for stenciling small graphics, designs, words, or the like, to a substrate such as a shirt, and once the stenciling pass has occurred, and the squeegee is removed, the screen will bounce upwardly, separating itself from the substrate, so that a clean, crisp print of the design is applied to the shirt, or the like, without any smudging, particularly when the stenciling frame is removed. Additionally, as portrayed above, the foam frame can be moved quickly to multiple substrates and positioned adequately without fear that ink will prematurely be applied to the substrate. Lastly, the foam frame provides a lightweight, inexpensive structure for cleaning, drying in the desired flat state and storing screen stencils in a space efficient manner while not in use.

(23) Upon reviewing the subject matter of this invention, various alternative embodiments will become obvious to those skilled in the art, as can be understood. For example, the frame may be formed from any number of polymeric materials, with varying dimensions and strengths of adhesions applied. Additionally, a non-skid surface could be achieved through an inherent process such as stamping the foam, or an applied process such as an application of rubber or additional plastic coating, or such may simply not be needed at all.

(24) Variations or modifications to the subject matter of this invention, as just described, may occur to those skilled in the art upon review of the summary of the invention as provided herein. The description of the invention, as set forth in the preferred embodiment, and its depiction in the drawings, are provided for illustrative purposes only. Any such variations are intended to be encompassed within the scope of any claims to patent protection issuing herein.