US20170172247A1

US20170172247A1 - Waterproofing method for footwear

Info

Publication number: US20170172247A1
Application number: US15/383,685
Authority: US
Inventors: Sangmin Lee
Original assignee: Chinook Asia LLC
Current assignee: Chinook Asia LLC
Priority date: 2015-12-17
Filing date: 2016-12-19
Publication date: 2017-06-22
Also published as: WO2017106844A1

Abstract

A method for waterproofing footwear may include spraying a waterproofing liquid onto an inner surface of the upper of the footwear during the manufacturing process. A liner attached to the footwear may be turned inside out and/or pulled at least partially out of the upper to uncover the interior surface of the upper. By spraying the liquid onto the interior surface and onto the seam between the liner and the upper, these surfaces may be made waterproof.

Description

CROSS-REFERENCES

This application claims the benefit under 35 U.S.C. §119(e) of the priority of U.S. Provisional Patent Application Ser. No. 62/268,947, filed Dec. 17, 2015, the entirety of which is hereby incorporated by reference for all purposes.

FIELD

This disclosure relates to systems and methods for waterproofing footwear. More specifically, the disclosed embodiments relate to applying a waterproofing material to a surface of an article of footwear.

INTRODUCTION

Modern footwear may require various features, depending on the intended use of the footwear. For example, footwear for outdoor use may need to be ruggedized, waterproofed, and/or safety-enhanced by the manufacturer. Various materials and products have been used to accomplish waterproofing and/or water resistance. These methods may require use of certain outer materials and/or may require modification of the exterior of an article of footwear. This modification may be undesirable for aesthetic or other reasons.

SUMMARY

The waterproofing methods and systems according to the present teachings provide a waterproof barrier by spraying a waterproofing liquid onto an interior surface of the upper of an article of footwear, and may further waterproof a seam between the upper and an attached liner.
In some embodiments, a method for waterproofing footwear may include: attaching an inner liner to an upper of an article of footwear by sewing the inner liner to the upper to form a seam, such that a plurality of stitch holes are formed in the upper along the seam; turning the inner liner inside out, such that the seam and an interior surface of the upper are uncovered; and spraying a waterproofing liquid through an opening in a bottom portion of the upper onto the seam and the interior surface of the upper; wherein the plurality of stitch holes are substantially filled by the waterproofing liquid.
In some embodiments, a method for waterproofing footwear may include: positioning an inner lining attached to an upper of an article of footwear such that an inner surface of the upper is exposed; and spraying a waterproofing liquid onto the exposed inner surface of the upper through an opening in a bottom portion of the upper.
In some embodiments, a system for waterproofing footwear may include: a spray nozzle in fluid communication with a source of waterproofing liquid; a pressure source operatively connected to the source of waterproofing liquid; and a fixture for holding an upper of an article of footwear, such that an opening of the upper allows access to an inner surface of the upper; wherein the spray nozzle is insertable into the opening of the upper and configured to spray the waterproofing liquid onto the inner surface of the upper.
Features, functions, and advantages may be achieved independently in various embodiments of the present disclosure, or may be combined in yet other embodiments, further details of which can be seen with reference to the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram of an illustrative waterproofing system in accordance with aspects of the present disclosure.

FIG. 2 is a flow chart showing steps of an illustrative method for waterproofing footwear according to the present teachings.

FIG. 3 is a perspective view of an illustrative waterproofing system in use on an illustrative article of footwear, in accordance with aspects of the present disclosure.

FIG. 4 is a schematic view of an illustrative embodiment of a method for waterproofing footwear according to the present teachings.

FIG. 5 is a schematic view of another illustrative embodiment of a method for waterproofing footwear according to the present teachings.

FIG. 6 is a schematic view of yet another illustrative embodiment of a method for waterproofing footwear according to the present teachings.

FIG. 7 is an elevation view of an illustrative spray fixture suitable for use in a waterproofing system according to the present teachings.

FIG. 8 is a sectional view of an illustrative spray nozzle suitable for use in waterproofing systems according to the present teachings.

FIG. 9 is a sectional view of an illustrative fan-type spray nozzle suitable for use in waterproofing systems according to the present teachings.

FIG. 10 is a sectional view of an illustrative impingement-type spray nozzle suitable for use in waterproofing systems according to the present teachings.

FIG. 11 is a side view of an illustrative spiral-type spray nozzle suitable for use in waterproofing systems according to the present teachings.

FIG. 12 is a sectional view of an illustrative swirl-type spray nozzle suitable for use in waterproofing systems according to the present teachings.

DESCRIPTION

Various aspects and examples of systems for waterproofing footwear, as well as related methods, are described below and illustrated in the associated drawings. Unless otherwise specified, a footwear waterproofing system or method and/or its various components may, but are not required to, contain at least one of the structure, components, functionality, and/or variations described, illustrated, and/or incorporated herein. Furthermore, the process steps, structures, components, functionalities, and/or variations described, illustrated, and/or incorporated herein in connection with the present teachings may, but are not required to, be included in other similar footwear waterproofing methods and systems. The following description of various examples is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. Additionally, the advantages provided by the examples and embodiments described below are illustrative in nature and not all examples and embodiments provide the same advantages or the same degree of advantage.

DEFINITIONS

The following definitions apply herein, unless otherwise indicated.
“Substantially” means to be essentially conforming to the particular dimension, range, shape, concept, or other aspect modified by the term, such that a feature or component need not conform exactly. For example, a “substantially cylindrical” object means that the object resembles a cylinder, but may have one or more deviations from a true cylinder.
“Comprising,” “including,” and “having” (and conjugations thereof) are used interchangeably to mean including but not necessarily limited to, and are open-ended terms not intended to exclude additional, unrecited elements or method steps.
Terms such as “first”, “second”, and “third” are used to distinguish or identify various members of a group, or the like, and are not intended to show serial or numerical limitation.
Illustrative Waterproofing System
As shown in FIG. 1, this section describes an illustrative system 100 for waterproofing footwear.
Referring to FIG. 1, waterproofing system 100 includes a source 102 of a waterproofing solution 104 that may be pressurized by a pressure source 106. A spray nozzle 108 is in fluid communication with source 102, such as by way of a hose 110 or other suitable line.
Source 102 may include a chamber, reservoir, tank, or other suitable container configured to contain the liquid waterproofing solution 104. In systems where liquid 104 is pressurized, the container of source 102 must be able to withstand the operating pressures involved.
Waterproofing solution 104, also referred to as a water repellent, may include any suitable liquid configured to provide a hydrophobic, water-resistant, or water-impermeable layer when applied to a destination surface. For example, waterproofing solution 104 may include a durable water repellent (DWR). In some examples, the waterproofing solution may contain or be combined with a bonding agent, to facilitate adherence to the target surface. In some examples, the waterproofing solution may be fluoropolymer-based. In some examples, the waterproofing solution may form a thick and/or impermeable layer or coating when dried/cured. In some examples, the waterproofing solution has a thick, rubberized appearance, and may be similar to the coating used on truck beds. Such a solution may not be ideal for application to the outside of an article of footwear (e.g., a shoe or boot).
Pressure source 106 may include any suitable source of pressure or motive force configured to cause liquid solution 104 to travel from the container of source 102 through hose 110 and exit nozzle 108. For example, pressure source 106 may include a source of pneumatic pressure, such as a pressurized air system or air compressor. For example, pressure source 106 may include a pump disposed in line with source 102 and hose 110. In some examples, pressure source 106 may comprise the force due to gravity. This may be utilized, for example, by physically disposing source 102 at a higher elevation than nozzle 108, such that liquid solution 104 is driven through the nozzle by the weight of the solution.
Spray nozzle 108 may include any suitable device configured to spray the liquid water repellent in a predictable dispersion pattern. Nozzle 108 may include a single-outlet nozzle or may include a compound nozzle having a plurality of outlets. In general, the pressurized water repellent liquid is passed through an orifice to atomize the liquid. As indicated in FIG. 1, spray nozzle 108 may be configured to oscillate or otherwise move, such as in a rotating and/or reciprocating pattern. Movement of spray nozzle 108 may be produced using an actuator 112. Actuator 112 may include any suitable device or structure configured to move nozzle 108 to produce full spray coverage of a target surface. In some examples, actuator 112 may comprise a user's hand or arm, such that movement is manually produced. In some examples, actuator 112 may be mechanical, such as when using a powered, telescoping nozzle assembly or articulating arm.
Hose 110 may include any suitable line configured to transport pressurized water repellent fluid from source 102 to nozzle 108. Hose 110 may include flexible line, rigid piping, reinforced hose, and/or the like, or any combination of these. If nozzle 108 is configured to spin (or the like), hose 110 may be connected to nozzle 108 by a swiveling or rotating connector joint.
As indicated in FIG. 1, an article of footwear 114 may comprise the target of system 100. For example, an interior surface of an upper portion 116 of footwear 114 may be sprayed using nozzle 108, while an inner lining or liner 118 of footwear 114 is displaced such that the inner surface of the upper is accessible by the spray nozzle. A seam may exist between the liner and the upper, where the liner is sewn to the upper. Spraying liquid solution 104 into the upper may cause the seam (i.e., holes or openings of the seam) to be waterproofed (e.g., by filling the holes with waterproofing solution). In this example, the sole of the footwear has not yet been attached, and the interior of the upper is accessed through the base of footwear 114 (i.e., where the sole will later be attached).
Illustrative Waterproofing Method
This section describes steps of an illustrative method for applying a water repellent to an article of footwear during the manufacturing process; see FIG. 2. Aspects of system 100 for waterproofing footwear may be utilized in the method steps described below. Where appropriate, reference may be made to previously described components and systems that may be used in carrying out each step. These references are for illustration, and are not intended to limit the possible ways of carrying out any particular step of the method.
FIG. 2 is a flowchart illustrating steps performed in an illustrative method, and may not recite the complete process or all steps of the method. FIG. 2 depicts multiple steps of a method, generally indicated at 200, which may be performed in conjunction with system 100 according to aspects of the present disclosure. Although various steps of method 200 are described below and depicted in FIG. 2, the steps need not necessarily all be performed, and in some cases may be performed in a different order than the order shown. Steps that may be optional and/or contextual are outlined using dashed lines.
At step 202, an upper portion of an article of footwear may be manufactured or otherwise obtained. The upper comprises one or more outer portions of the footwear other than the sole portion. The upper may be manufactured using standard or typical methods. In some examples, the upper may be obtained as an intermediate article of manufacture, from another source, another manufacturing process, and/or a stored supply of pre-made uppers.
Similarly, at step 204, a liner portion of the article of footwear may be manufactured or obtained. The liner, also referred to as a lining or a bootie, may include any suitable lining configured to fit within the upper of step 202, and to function as an inner layer for comfort, insulation, or other purposes. The liner be may be manufactured using standard or typical methods. In some examples, the liner may be obtained as an intermediate article of manufacture, from another source, another manufacturing process, and/or a stored supply of pre-made liners. In some examples, the liner may comprise a waterproof or water-resistant material.
At step 206, the liner portion of the footwear is attached to the upper portion of the footwear. This attachment may be performed using standard methods, such as by sewing or stitching the liner to the upper. For example, the liner may be stitched to the upper in such a way that the liner fits inside the upper and is attached near the top of the two articles. For example, the liner may be stitched to the upper at around at least a portion of a mutual periphery. For example, the inner liner may be attached to the upper by sewing the inner liner to the upper to form a seam, such that a plurality of stitch holes are formed in the upper along the seam. Any suitable method may be used to connect the liner to the upper.
At step 208, the liner is turned inside out. In other words, the liner may be pulled out of its normal position within the upper, and extracted from the upper as much as possible or practicable. Following this step, a substantive portion of the inner surface of the upper will no longer be covered by (i.e., lined by) the liner. Exposing the inner surface of the upper in this manner allows the next step to be effective, by providing a target surface for the water repellent substance. In some examples, this step may be performed in conjunction with step 206. For example, the liner may be attached to the upper such that the liner is already in the pulled-out configuration. In some examples, the liner may be turned inside out, such that the seam and the interior surface of the upper are uncovered.
At step 210, water repellent/waterproofing solution is applied to the inner (i.e., interior) surface of the footwear. In other words, the solution is applied to the interior of the upper. This application may be performed by spraying a solution onto the inner surface of the upper, e.g., using an apparatus or system such as system 100, described above. By spraying the waterproofing solution onto the inner surface of the upper, the upper will be provided with a layer of hydrophobic protection to block water incursion into the liner layer during use. In other words, a waterproof layer is created at the inner surface of the upper layer, preventing any water that passes through the upper from wetting the liner or bootie.
Additionally, spraying the interior will plug any holes created during the stitching process (e.g., along the seam between the bootie and the upper), filling them with the waterproofing material. The standard process of taping such seams to physically cover the holes may or may not be used in conjunction with this step. In some examples, such taping is rendered unnecessary due to the spray-filling of these holes or apertures. In some examples, spraying the waterproofing liquid through the opening in the bottom portion of the upper onto the seam and the interior surface of the upper, wherein the plurality of stitch holes are filled by the waterproofing liquid.
This spraying of the waterproofing liquid onto the interior surface of the upper may be performed before attaching the sole portion of the footwear, such that an opening exists at the base or bottom portion of the upper. The waterproofing liquid may be applied through this opening, for example by a spray nozzle disposed outside the opening and/or by a spray nozzle passing into the interior cavity of the upper through the bottom opening.
At step 212, the waterproofing solution is allowed to cure or dry for a suitable length of time, depending on the substance used. In other words, the liquid may be dried or cured to form a waterproof coating on the inner surface of the upper.
At step 214, the liner may be turned right side out, i.e., inserted back into the upper such that the liner again conforms to the interior of the upper. In some examples, inserting the lining into the upper may cause the lining to be adjacent to the inner surface of the upper.
At step 216, the upper and liner continue in a footwear manufacturing process. For example, a sole may be attached to the upper (or vice versa), e.g., to cover the opening in the base or bottom portion of the upper.
Illustrative Spray Modalities
As shown in FIGS. 3-8, this section describes various spray application modalities, each of which may be suitable for use with or as part of system 100 and/or method 200 (e.g., for carrying out step 210 described above).
Throughout the following description, the upper and associated lining in each drawing will be referred to as upper 300 and lining 302 of an article of footwear 304. This footwear and its components are used for illustration only, as any suitable upper and/or lining may be waterproofed using the devices below.
FIG. 3 depicts an illustrative spray system 310, in which a spray nozzle 312 sprays a broad (e.g., conical) pattern of waterproofing solution 314 on an interior surface 316 of upper 300 of article of footwear 304. Lining 302 of footwear 304 is pulled out of the footwear through an upper opening, exposing surface 316 to solution 314. In this example, spray nozzle 312 is on the distal end of a spray head or wand 318, which may be configured to move up and down (i.e., into and out of the upper) and/or spin or rotate to ensure proper spray coverage. A foot pedal (not shown) or other suitable actuator may be used to initiate the spraying and/or oscillating action of the nozzle. In some examples, the spray nozzle and wand may extend through upper 300 and into lining 302, thereby spraying solution 314 onto the lining. Footwear 304 may be held in a fixture or may be held by hand by an operator. Whether in a fixture or handheld, footwear 304 may be moved (e.g., translated, rotated, tilted, etc.) during the spray operation to further ensure coverage of the solution onto all desired portions of surface 316.
FIG. 4 depicts a hand-operated spray system 330, in which a garden hose style spray nozzle 332 is used to spray the waterproofing solution on interior surface 316 of upper 300. The upper may be held by hand (as shown) or in a fixture. FIG. 5 depicts an automated spray system 340, in which a spray nozzle 342 is operatively connected to an articulated mechanical arm 344. Arm 344 may comprise a computer-numerical-control (CNC) arm or a robotic arm, such that the waterproofing solution is applied automatically, according to an algorithmic program. Any suitable arm and/or programming may be utilized to carry out method 200. FIG. 6 depicts a spray system 350, in which a user-mounted backpack 352 functions as the waterproofing solution container (e.g., solution source 102) and, in some examples, the pressure source (e.g., source 106). Backpack 352 is connected to hand-operated spray nozzle 354.
FIG. 7 depicts a multi-nozzle spray system 360. System 360 includes an interior surface spray nozzle 362, and one or more exterior spray nozzles 364A, 364B, 364C, all mounted on a common fixture or frame 366. More or fewer nozzles may be present. System 360 may be used to spray-apply liquid solutions to multiple surfaces of footwear 304 simultaneously. In some examples, the same waterproofing solution is sprayed through all nozzles. In some examples, different liquids may be sprayed through different spray nozzles, as desired.
Illustrative Nozzles
As shown in FIGS. 8-12, this section describes various nozzle types that may be suitable for use in embodiments of system 100, method 200, and/or any of the modalities depicted in FIGS. 3-7. These nozzles are examples of spray nozzle 108, described above. Each nozzle may be selected for its flow and spray characteristics, as desired for the particular application at hand. Other nozzle types may be suitable, and these are provided for illustration only.
FIG. 8 is a sectional side view of a spray nozzle 400. Nozzle 400 includes a body 402 having an inlet 404 and an outlet orifice 406. Pressurized fluid passes into nozzle 400 through inlet 404, and then out of the nozzle through the smaller-diameter orifice 406, thereby dropping the pressure and increasing the velocity of the outgoing fluid. A simple nozzle such as nozzle 400 may result in a generally conical spray pattern.
FIG. 9 is a sectional side view of a fan-type spray nozzle 410. Nozzle 410 includes a body 412, an inlet 414, an outlet orifice 416, and an outlet V-notch 418 formed in body 412. This nozzle operates similar to nozzle 400, but the combination of features results in a fan-shaped spray pattern.
FIG. 10 is a sectional side view of an impingement-type spray nozzle 420. Nozzle 420 includes a body 422, an inlet 424, an outlet orifice 426, and an angled impingement surface 428 in the path of fluid exiting orifice 426. Angled surface 428 breaks up the exiting stream into smaller droplets, shaping and directing the (e.g., fan-shaped) spray pattern in a desired direction.
FIG. 11 is a side view of a spiral-type spray nozzle 430. Nozzle 430 includes a body 432, an inlet 434, and an outlet orifice 436. A spiral-shaped extension 438 extends on the outlet side of the nozzle, such that fluid is directed in overlapping conical spray patterns by the extension.
FIG. 12 is a sectional side view of a swirl-type spray nozzle 440. Nozzle 440 includes a body 442, an inlet 444, an outlet orifice 446, and a stationary core 448 that induces a rotary fluid motion, thereby causing a swirling of the fluid in the swirl chamber 450. A hollow-cone spray pattern is discharged from the outlet orifice.
Additional Examples and Illustrative Combinations
This section describes additional aspects and features of waterproofing methods and systems in accordance with aspects of the present disclosure, presented without limitation as a series of paragraphs, some or all of which may be alphanumerically designated for clarity and efficiency. Each of these paragraphs can be combined with one or more other paragraphs, and/or with disclosure from elsewhere in this application, in any suitable manner. Some of the paragraphs below may expressly refer to and further limit other paragraphs, providing without limitation examples of some of the suitable combinations.
B0. A method for waterproofing footwear, the method comprising:
attaching an inner liner to an upper of an article of footwear by sewing the inner liner to the upper to form a seam, such that a plurality of stitch holes are formed in the upper along the seam;
turning the inner liner inside out, such that the seam and an interior surface of the upper are uncovered; and
spraying a waterproofing liquid through an opening in a bottom portion of the upper onto the seam and the interior surface of the upper;
wherein the plurality of stitch holes are filled by the waterproofing liquid.
B1. The method of B0, wherein the waterproofing liquid comprises a durable water repellent.
B2. The method of B0 or B1, further including attaching a sole portion of the article of footwear to the opening in the bottom portion of the upper.
B3. The method of any of B0 through B2, wherein spraying the waterproofing liquid includes spraying the liquid through a nozzle coupled to a pressurized source of the waterproofing liquid.
B4. The method of B3, wherein spraying the waterproofing liquid includes automatically moving the nozzle within the upper using an actuator operatively connected to the nozzle.
B5. The method of any of B0 through B4, further comprising allowing the waterproofing liquid to cure for a selected amount of time before repositioning the liner to cover the interior surface of the upper.
C0. A method for waterproofing footwear, the method comprising:
positioning an inner lining attached to an upper of an article of footwear such that an inner surface of the upper is exposed; and
spraying a waterproofing liquid onto the exposed inner surface of the upper through an opening in a bottom portion of the upper.
C1. The method of paragraph C0, wherein positioning the inner lining includes causing the inner lining to be withdrawn at least partially through a top opening of the upper.
C2. The method of paragraph C0, wherein the opening in the bottom of the upper comprises an attachment area for a sole of the footwear.
C3. The method of paragraph C1, further comprising attaching the sole of the footwear to the upper.
C4. The method of any of paragraphs C0 through C3, further including attaching the lining to the upper by sewing the lining to the upper.
C5. The method of paragraph C4, wherein the lining is sewn to the upper with the lining already positioned at least partially out of the upper.
C6. The method of paragraph C4, wherein sewing the lining to the upper causes one or more holes to be present in the liner and the upper, and wherein spraying the waterproofing liquid causes the one or more holes to be filled.
C7. The method of any of paragraphs C0 through C6, further including drying the liquid to form a waterproof coating on the inner surface of the upper.
C8. The method of any of paragraphs C0 through C7, further including inserting the lining into the upper, such that the lining is adjacent to the inner surface of the upper.
C9. The method of any of paragraphs C0 through C8, further including manufacturing the upper.
C10. The method of any of paragraphs C0 through C9, further including manufacturing the lining.
C11. The method of any of paragraphs C0 through C10, wherein the lining comprises a waterproof material.
C12. The method of any of paragraphs C0 through C11, wherein the upper comprises leather.
D0. A system for waterproofing footwear, the system comprising:
a spray nozzle in fluid communication with a source of waterproofing liquid;
a pressure source operatively connected to the source of waterproofing liquid; and
a fixture for holding an upper of an article of footwear, such that an opening of the upper allows access to an inner surface of the upper;
wherein the spray nozzle is insertable into the opening of the upper for spraying the waterproofing liquid onto the inner surface.
D1. The system of paragraph D0, wherein the spray nozzle has a single orifice.
D2. The system of any of paragraphs D0 through D1, wherein the spray nozzle is rotatable.
D3. The system of any of paragraphs D0 through D2, wherein the spray nozzle is operatively connected to a reciprocating wand portion, the wand portion configured to reciprocate into and out of the upper.
D4. The system of any of paragraphs D0 through D3, wherein the pressure source comprises pressurized air.

ADVANTAGES, FEATURES, BENEFITS

The different embodiments and examples of the waterproofing systems and methods described herein provide several advantages over known solutions for waterproofing footwear. For example, illustrative embodiments and examples described herein allow application of waterproofing solution/coating directly on the inner surface of the exterior portion (i.e., upper) of the footwear. This prevents moisture penetration beyond the exterior material, and therefore prevents such moisture being absorbed by a foam or other lining of the footwear. This also improves performance of the boot or shoe by quicker drying and reduced overall water absorption.
Additionally, and among other benefits, illustrative embodiments and examples described herein allow waterproof spray to be applied up and down on the interior of the shoe or boot, until the desired area is fully covered. The lining material may then be pulled through after drying the sprayed solution, and lasted. This improves manufacturing efficiency.
No known system or method can perform these functions, particularly in the area of waterproofing of footwear. However, not all embodiments and examples described herein provide the same advantages or the same degree of advantage.

CONCLUSION

The disclosure set forth above may encompass multiple distinct examples with independent utility. Although each of these has been disclosed in its preferred form(s), the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense, because numerous variations are possible. To the extent that section headings are used within this disclosure, such headings are for organizational purposes only. The subject matter of the disclosure includes all novel and nonobvious combinations and subcombinations of the various elements, features, functions, and/or properties disclosed herein. The following claims particularly point out certain combinations and subcombinations regarded as novel and nonobvious. Other combinations and subcombinations of features, functions, elements, and/or properties may be claimed in applications claiming priority from this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure.

Claims

What is claimed is:

1. A method for waterproofing footwear, the method comprising:

attaching an inner liner to an upper of an article of footwear by sewing the inner liner to the upper to form a seam, such that a plurality of stitch holes are formed in the upper along the seam;

turning the inner liner inside out, such that the seam and an interior surface of the upper are uncovered; and

spraying a waterproofing liquid through an opening in a bottom portion of the upper onto the seam and the interior surface of the upper;

wherein the plurality of stitch holes are substantially filled by the waterproofing liquid.

2. The method of claim 1, wherein the waterproofing liquid comprises a durable water repellent.

3. The method of claim 1, further including attaching a sole portion of the article of footwear to the opening in the bottom portion of the upper.

4. The method of claim 1, wherein spraying the waterproofing liquid includes spraying the liquid through a nozzle coupled to a pressurized source of the waterproofing liquid.

5. The method of claim 4, wherein spraying the waterproofing liquid includes automatically moving the nozzle within the upper using an actuator operatively connected to the nozzle.

6. The method of any of claim 1, further comprising allowing the waterproofing liquid to cure for a selected amount of time before repositioning the liner to cover the interior surface of the upper.

7. A method for waterproofing footwear, the method comprising:

positioning an inner lining attached to an upper of an article of footwear such that an inner surface of the upper is exposed; and

spraying a waterproofing liquid onto the exposed inner surface of the upper through an opening in a bottom portion of the upper.

8. The method of claim 7, wherein positioning the inner lining includes causing the inner lining to be withdrawn at least partially through a top opening of the upper.

9. The method of claim 7, wherein the opening in the bottom portion of the upper comprises an attachment area for a sole of the article of footwear.

10. The method of claim 9, further comprising attaching the sole of the footwear to cover the opening in the bottom of the upper.

11. The method of claim 7, further including attaching the lining to the upper by sewing the lining to the upper.

12. The method of claim 11, wherein sewing the lining to the upper causes one or more holes to be present in the liner and in the upper, and wherein spraying the waterproofing liquid causes the one or more holes to be filled.

13. The method of claim 7, further including drying the liquid to form a waterproof coating on the inner surface of the upper.

14. The method of claim 7, further including inserting the lining into the upper, such that the lining is adjacent to the inner surface of the upper.

15. The method of claim 7, wherein the lining comprises a waterproof material.

16. A system for waterproofing footwear, the system comprising:

a spray nozzle in fluid communication with a source of a waterproofing liquid;

a pressure source operatively connected to the source of the waterproofing liquid; and

a fixture configured to hold an upper of an article of footwear, such that an opening of the upper allows access to an inner surface of the upper;

wherein the spray nozzle is insertable into the opening of the upper and configured to spray the waterproofing liquid onto the inner surface of the upper.

17. The system of claim 16, wherein the spray nozzle has a single orifice.

18. The system of claim 16, wherein the spray nozzle is rotatable.

19. The system of claim 16, wherein the spray nozzle is coupled to a wand portion having an actuator configured to reciprocate the wand portion into and out of the upper.

20. The system of claim 16, wherein the pressure source comprises pressurized air.