阅读说明：本技术 用于在便携式电子设备的制造中使用的可印刷环形粘合剂 (Printable annular adhesive for use in the manufacture of portable electronic devices ) 是由 L·E·胡顿 A·E·弗莱彻 D·W·贾维斯 M·拉姆马 R·H·M·丁 于 2019-05-31 设计创作，主要内容包括：本发明题为“用于在便携式电子设备的制造中使用的可印刷环形粘合剂”。本专利申请涉及用于在制造便携式电子设备期间使用的环形形状的粘合剂。便携式电子设备可以具有小外形,诸如是平板电脑或移动电话。可印刷粘合剂以与便携式电子设备的表面符合的形状被分配在剥离衬件上。可印刷粘合剂的形状遵循由连续闭合曲线表征的路径,并且包围剥离衬件上的在其中没有分配可印刷粘合剂的区域。可印刷粘合剂的宽度沿连续闭合曲线可以变化,以适形于便携式电子设备的一个或多个表面中的特征部。所述特征部可以具有小于一毫米的尺寸。可印刷粘合剂可以通过丝网印刷工艺或者通过经由喷嘴分配可印刷粘合剂来被施用到剥离衬件。(The invention is entitled "printable annular adhesive for use in the manufacture of portable electronic devices". The present application relates to an adhesive in a ring shape for use during the manufacture of portable electronic devices. The portable electronic device may have a small form factor, such as a tablet computer or a mobile phone. The printable adhesive is dispensed on the release liner in a shape that conforms to the surface of the portable electronic device. The shape of the printable adhesive follows a path characterized by a continuous closed curve and encompasses the area on the release liner where the printable adhesive is not dispensed. The width of the printable adhesive may vary along a continuous closed curve to conform to features in one or more surfaces of the portable electronic device. The features may have a dimension of less than one millimeter. The printable adhesive may be applied to the release liner by a screen printing process or by dispensing the printable adhesive through a nozzle.)

1. A component for use in manufacturing a portable electronic device, the component comprising:

stripping the liner; and

a printable adhesive dispensed on the release liner in a shape conforming to a surface of the portable electronic device,

wherein the shape of the printable adhesive:

following a path characterized by a continuous closed curve,

surrounding areas of the release liner not having printable adhesive dispensed therein, and

having a width that varies along the path.

2. The component of claim 1, wherein the printable adhesive is dispensed on the release liner using a screen printing process.

3. The component of claim 1, wherein the printable adhesive is dispensed on the release liner via a nozzle controlled by a robotic arm.

4. A component according to claim 2 or 3, wherein the shape comprises a feature characterised by a transition from a first width at a first point in the path to a second width at a second point in the path.

5. The component of claim 4, wherein the width of the shape of the printable adhesive is less than one millimeter at all points along the path.

6. The component as recited in claim 1, wherein the printable adhesive dispensed in the shape on the release liner is subsequently cut into a second shape via a die cutting process to form one or more features in the shape.

7. The component as claimed in claim 1 or 2 or 6, wherein the printable adhesive is cooled prior to being cut via the die cutting process.

8. The component of claim 7, wherein the release liner comprises a polymer substrate coated with a thin layer of adhesive.

9. The component of claim 7, wherein the release liner comprises a polymer coated paper blank.

10. The component of claim 1, wherein the printable adhesive is a pressure sensitive adhesive.

11. A method for adhesively bonding at least two components of a portable electronic device, the method comprising:

providing a release liner;

dispensing a printable adhesive onto a surface of the release liner in a shape wherein:

the width of the printable adhesive varies along a path to conform to one or more features formed in a surface of the portable electronic device, and

the shape defines a central region on the surface of the release liner, the central region characterized by being free of printable adhesive and being completely surrounded by the printable adhesive; and

applying the printable adhesive to the surface of the portable electronic device.

12. The method of claim 11, wherein the shape is characterized by at least one feature having a dimension of less than one millimeter.

13. The method of claim 11 or 12, wherein said dispensing said printable adhesive in said shape is characterized by an accuracy of a nominal shape on said surface of said release liner of ± 0.05 inches.

14. The method of claim 11, wherein the portable electronic device comprises a tablet computer.

15. The method of claim 13, wherein the surface of the portable electronic device comprises a flange formed in a cavity of a housing of the portable electronic device.

16. The method of claim 11, wherein the assigning comprises one of:

dispensing said printable adhesive through a screen onto said surface of said release liner, or

Dispensing the printable adhesive through a nozzle onto the surface of the release liner.

17. A portable electronic device comprising components bonded via a printable adhesive, the portable electronic device comprising:

a housing comprising an internal cavity, wherein one or more operational components of the portable electronic device are disposed within the cavity and attached to the housing;

a display assembly including a display and a glass substrate overlying a top surface of the display; and

an adhesive dispensed directly onto at least one surface of the housing via a printing process, the adhesive forming a continuous closed path around an opening in the housing to the cavity.

18. The portable electronic device of claim 17, wherein the printing process comprises a screen printing process.

19. The portable electronic device of claim 17, wherein the printing process comprises dispensing the adhesive via a nozzle controlled by a robotic arm.

20. The portable electronic device of claim 18 or 19, wherein the portable electronic device comprises a tablet computer.

Technical Field

Embodiments described herein relate generally to manufacturing techniques that utilize adhesives. More particularly, embodiments herein relate to printable adhesives that are dispensed in a shape that conforms to a surface of a portable electronic device.

Background

Adhesives are often used in a variety of manufacturing processes. For example, an adhesive may be used to attach the windshield to the vehicle frame. The adhesive may also form a seal between the frame and the windshield that prevents or limits water from entering the passenger compartment of the automobile. As another example, an adhesive may be used to secure two plastic parts together for a child's toy or other consumer product. Adhesives are needed for use in a variety of applications, including in the manufacture of consumer electronics.

However, there are a number of technical challenges when using adhesives in a manufacturing environment. For example, adhesives are often applied in liquid form, which can be difficult to apply to a particular geometry. Other adhesives such as Pressure Sensitive Adhesives (PSAs) may be applied from a release liner that is then discarded to produce waste. These challenges can be particularly difficult for certain geometries, such as toroidal shapes.

Fig. 1 illustrates a technique for manufacturing an adhesive for application to a surface of a portable electronic device, according to the prior art. In various applications, the adhesive may be applied to a surface of a portable electronic device. The surface may comprise a complex geometry, such as a narrow flange formed around the perimeter of an internal cavity of a housing of the portable electronic device. The flange may be, for example, 50 mils (e.g., 0.05 inches) wide or less around the perimeter, and the width of the flange may vary along the length of the flange. The dashed lines in fig. 1 show the shape 110 of the surface.

The adhesive may be provided to the manufacturer from an adhesive supplier on a roll having one or more release liners. The manufacturer may then run a roll of adhesive through a die cutter to cut the shape 110 of the adhesive for application to the surface. However, when the shape 110 conforms to a large closed curve, such as a large circle, ellipse, or rectangle, the amount of wasted adhesive can be significant (up to 90% or more wasted material). For example, FIG. 1 shows a large interior portion 120 of adhesive inside the closed shape 110 to be discarded. It will be appreciated that this discarded material adds to the cost of raw materials that must be purchased by the manufacturer.

Fig. 2 shows another technique for manufacturing an adhesive for application to a surface of a portable electronic device according to the prior art. The closed shape 110 of adhesive may be divided into sections 210 and different sections 210 of the shape 110 may be cut from different portions of the roll of adhesive in order to reduce the amount of waste. As shown in fig. 2, the shape 110 is divided into four sections 210: left section 210-1, right section 210-2, top section 210-3, and bottom section 210-4. Each of these sections 210 may be die cut from a small strip of roll of adhesive, thereby reducing the amount of wasted adhesive. However, this technique has certain disadvantages compared to the first technique shown in fig. 1.

For example, a continuous ring of adhesive may be used to provide a seal between the two components, thereby preventing or limiting the ingress of water into the cavity of the device. By dividing the continuous loop into sections, there may be gaps in the adhesive loop where the alignment of two adjacent sections is not precise when applied to a surface. Furthermore, there may be gaps in the seal where the two sections overlap, as the double thickness of the adhesive at the location of the joint prevents a seal from being formed correctly between the two complementary parts. Furthermore, the application of four sections may be more time consuming and difficult during the assembly process, thereby reducing the throughput of the assembly line. Accordingly, it is desirable to find solutions for preparing adhesives for use in manufacturing portable electronic devices that result in more efficient use of raw materials.

Disclosure of Invention

Various embodiments are described herein that relate to manufacturing techniques associated with adhesives. More specifically, disclosed herein are techniques that enable printable adhesives to be dispensed on release liners in shapes that conform to one or more surfaces of a portable electronic device. The shape may be referred to as a torus shape, following a path characterized by a continuous closed curve forming a circle, ellipse, rectangle, or other non-intersecting regular or irregular curve. The width of the adhesive may vary along the path such that the shape includes one or more features characterized by a transition from a first width at a first point in the path to a second width at a second point in the path. The features may conform to features in the one or more surfaces of the portable electronic device. Such features may be characterized as having small dimensions, e.g., less than one millimeter to several millimeters.

In some embodiments, the components are manufactured that can be shipped to the final assembly location of the portable electronic device. The component may include a release liner and a printable adhesive dispensed on the release liner in a shape conforming to a surface of the portable electronic device. Shape of the printable adhesive: following a path characterized by a continuous closed curve forming a loop; surrounding an area of the release liner where no printable adhesive is dispensed; and has a width that varies along the path.

In some embodiments, the printable adhesive is dispensed on the release liner using a screen printing process. A mesh or screen may be provided with a stencil formed thereon such that printable adhesive may be pressed through the screen onto the release liner in a desired shape formed in the negative spaces of the stencil. In other embodiments, the printable adhesive is dispensed on the release liner via a nozzle controlled by a robotic arm. The nozzle may comprise a needle or jet dispensing mechanism which forces a drop of printable adhesive through the nozzle using, for example, a piezoelectric element.

In some embodiments, the shape includes a feature characterized by a transition from a first width at a first point in the path to a second width at a second point in the path. The transition may be sharp (such as a transition characterized by edges at right angles to the sides of the shape at the two widths), or gradual (such as a curved transition from one width to the other). In some embodiments, the width of the shape of the printable adhesive is less than one millimeter at all points along the path.

In some embodiments, the printable adhesive is dispensed in a final shape that is applied to the surface of the portable electronic device. In other embodiments, the printable adhesive dispensed in the shape on the release liner is subsequently cut into a second shape via a die cutting process to form one or more features in the shape. In some embodiments, the printable adhesive is cooled prior to being cut via the die-cutting process.

In some embodiments, the release liner comprises a polymeric substrate coated with a thin layer of adhesive. In other embodiments, the release liner comprises a polymer coated paper substrate.

In some embodiments, the printable adhesive is a pressure sensitive adhesive. In other embodiments, the printable adhesive is a one-component adhesive activated by one of thermal or ultraviolet radiation.

In some embodiments, a method for adhesively coupling at least two components of a portable electronic device is disclosed. The method comprises the following steps: providing a release liner, dispensing a printable adhesive in a shape onto a surface of the release liner, and applying the printable adhesive to a surface of the portable electronic device. The width of the printable adhesive varies along a path to conform to one or more features formed in a surface of the portable electronic device. The shape defines a central region on the surface of the release liner, the central region being characterized by being free of printable adhesive and being completely surrounded by printable adhesive.

In some embodiments, the shape is characterized by at least one feature having a dimension of less than one millimeter. The width of the shape may be less than one millimeter at least one location around the perimeter of the shape, and in some embodiments, may be less than one millimeter at all locations around the perimeter of the shape.

In some embodiments, dispensing the printable adhesive in the shape is characterized by an accuracy of a nominal shape on the surface of the release liner of ± 0.05 inches. The accuracy may be defined by the mesh size of the screen used in the screen printing process. Alternatively, the accuracy may be defined by the nozzle shape and the droplet size of the nozzle dispensing process.

In some embodiments, the portable electronic device is a tablet computer. In some embodiments, the portable electronic device is a mobile phone. The surface of the portable electronic device may include a flange formed in a cavity of a housing of the portable electronic device. The adhesive may form a seal between the flange and a mating surface of a display assembly of the portable electronic device.

In some embodiments, the portable electronic device is produced using an adhesive. The portable electronic device includes a housing forming a cavity, a display assembly, and an adhesive dispensed directly onto at least one surface of the housing via a printing process. One or more operational components of the portable electronic device are disposed within the cavity and attached to the housing. The display assembly includes a display and a glass substrate stacked on a top surface of the display. The adhesive forms a continuous closed path around an opening in the housing to the cavity. The adhesive forms a seal between the display assembly and the housing.

Other aspects and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the embodiments.

Drawings

The present disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements.

Fig. 1 illustrates a technique for manufacturing an adhesive for application to a surface of a portable electronic device, according to the prior art.

Fig. 2 shows another technique for manufacturing an adhesive for application to a surface of a portable electronic device according to the prior art.

Fig. 3 illustrates a portable electronic device according to some embodiments.

Fig. 4 illustrates a cross-section of a portable electronic device according to some embodiments.

Fig. 5 illustrates components used in manufacturing a portable electronic device, according to some embodiments.

Fig. 6 illustrates components used in manufacturing a portable electronic device 300, according to some embodiments.

Fig. 7 is a flow diagram of a method for applying a ring-shaped printable adhesive to a surface of a portable electronic device, according to some embodiments.

Fig. 8 illustrates a technique for dispensing printable adhesive directly onto a surface of a portable electronic device, in accordance with some embodiments.

Detailed Description

Representative applications of the methods and apparatus according to the present application are described in this section. These examples are provided solely to add context and aid in the understanding of the described embodiments. It will thus be apparent to one skilled in the art that the embodiments may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the embodiments. Other applications are possible, such that the following examples should not be considered as limiting.

In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in accordance with the embodiments. While these embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments, it is to be understood that these examples are not limiting; such that other embodiments may be used and modifications may be made without departing from the spirit and scope of the embodiments.

The annular shaped adhesive presents particular challenges in the manufacturing process of portable electronic devices. Manufacturing the adhesive in a ring shape using conventional methods may result in inefficient use of raw materials. Manufacturing the annular shape in sections may reduce the amount of wasted raw material, but results in difficulties in the final assembly process due to the alignment of different sections to reform a continuous closed path of the annular shape. In the case where the multiple sections of adhesive are used to form a waterproof seal, gaps between the sections due to misalignment may result in water intrusion into the portable electronic device. These problems can be solved with different manufacturing techniques.

The printable adhesive may be dispensed onto the release liner using a process that enables raw materials of the adhesive to be dispensed in a desired shape that is applied to the attachment surface, in order to reduce the amount of wasted adhesive raw material. The precision of the printing process may be higher than that of conventional die-cutting processes used to cut shapes from a roll or sheet of pressure sensitive adhesive dispensed on a complete release liner, which enables more complex shapes with smaller features to be dispensed directly onto the release liner than can be achieved with die-cutting alone. For example, die cutting may make it difficult to produce a final shape having features with a width of less than 1 millimeter, while features produced in a screen printing process may have a precision comparable to the mesh count of the screen.

In some embodiments, the printable adhesive may be dispensed directly onto a surface of the portable electronic device. Screen printing or nozzle dispensing techniques may be used to dispense the printable adhesive directly onto the surface of the portable electronic device in a desired shape. The shape may have a low profile that corresponds to a flange or other feature formed in a housing of the portable electronic device. The size of the shape (including the width of printable adhesive at a particular location around a path characterized by a continuous closed curve forming a loop) may be less than one millimeter and with an accuracy of ± 50 microns.

These and other embodiments are discussed below with reference to fig. 3-8; however, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be taken as limiting.

Fig. 3 illustrates a portable electronic device 300 according to some embodiments. As shown in fig. 3, the portable electronic device 300 is a tablet computer. However, it should be understood that the portable electronic device 300 may take other forms, such as a mobile telephone (e.g., a smart phone, a cellular telephone, etc.), a laptop computer, a Personal Digital Assistant (PDA), a portable music player (e.g., an MP3 player), a digital camera, a portable gaming system, a remote control, and so forth.

As shown in fig. 3, the portable electronic device 300 includes a housing 302 and a display assembly 304. The housing 302 may be made of aluminum and include a cavity therein that houses one or more operational components (e.g., a processor, memory, printed circuit board, battery, integrated circuit, passive electronic components, audio transducer, image sensor, etc.). The display assembly 304 may include a Liquid Crystal Display (LCD), an Organic Light Emitting Diode (OLED) display, and the like. The display component 304 can present graphical data (e.g., pixel data, images, text, etc.) to a user of the portable electronic device 300. In some embodiments, the display assembly 304 includes a bracket attached to the display. The display assembly 304 may also include a glass substrate 306 that covers the display and the bracket. The glass substrate 306 may also include openings in which interface elements 308, such as buttons or touch-sensitive surfaces, are disposed.

Fig. 4 illustrates a cross-section of a portable electronic device 300 according to some embodiments. The cross-section corresponds to section line a-a in fig. 3 and depicts an adhesive joint between the housing 302 and the display assembly 304. As shown in fig. 4, the display assembly 304 includes a display unit 404 disposed within a cradle 402. The bracket 402 may be a sheet metal bracket or other structural member made of a structural material such as metal or plastic. The display unit 404 may be, for example, an LCD and LED backlight and one or more touch sensors for detecting touch inputs on the surface of the glass substrate 306 superimposed on the top surface of the display unit 404.

The housing 302 includes a cavity formed therein. Operational components are disposed in the cavity and may be attached to a surface of the housing 302. As shown in fig. 4, circuit components 406 (e.g., integrated circuit packages, capacitors, resistors, etc.) are coupled to a printed circuit board 408 that is attached to the bottom surface of the cavity within the housing 302. The housing 302 may also include a flange 412 formed within the cavity. The flange 412 may include one or more surfaces formed adjacent to edges of the housing 302 that define an opening through an outer surface of the housing 302 into the cavity. Adhesive 410 may be applied to the one or more surfaces of flange 412.

In some embodiments, the portable electronic device 300 may have a small profile such that the portable electronic device 300 may be handheld. In such embodiments, there may be multiple operational components disposed within the cavity of the housing 302, such that the flange 412 may be relatively small so as to avoid interference with any operational components. For example, the flange 412 may have a width of less than, for example, a few millimeters. In some cases, the flange 412 may have a width in a range of 0.7 millimeters to 1.3 millimeters. The width of the flange 412 may also vary around the perimeter of the housing 302 of the portable electronic device 300. For example, in some areas, the flange 412 may be less than one millimeter wide to accommodate other components of the portable electronic device 300. In an attempt to maintain adhesive tight dimensional tolerances (e.g., ± 50 microns), while including features less than 1 millimeter in width at multiple locations, it may be difficult to manufacture adhesive portions that conform to the annular shape that mate with the one or more surfaces of the flange 412.

In some implementations, the display assembly 304 is attached to the housing 302 via an adhesive 410. The back surface of the bracket 402 is attached to the adhesive 410 such that the back surface of the bracket 402 is opposite the mating surface of the flange 412. However, it should be understood that the mating surfaces may be designed at different locations or between different components of the portable electronic device 300. For example, the adhesive 410 may be placed between the back surface of the glass substrate 306 and the top surface of the housing 302. Alternatively, the location of the flange 412 may be different relative to the top or bottom surface of the housing 302. Further, the display assembly 304 may be adhesively coupled to a separate component that is attached to the housing 302 via a separate adhesive or mechanical fastener.

Fig. 5 illustrates a component 500 for use in manufacturing the portable electronic device 300, according to some embodiments. The component 500 (which may also be referred to as a part) may include a printable adhesive 502 dispensed onto a release liner 520. The printable adhesive 502 is dispensed in a ring shape. As used herein, an annular shape refers to a continuous closed curve with no intersections, where the width of the annular shape may vary along the curve. The annular shape may be circular, elliptical or rectangular. The annular shape may also be irregular, such as having multiple inflection points along one or more sides. An important feature of the annular shape is that the printable adhesive 502 is not dispensed within the interior portion of the annular shape. In other words, the printable adhesive 502 is not dispensed in the central region of the release liner 520 surrounded by the printable adhesive 502.

In some embodiments, the printable adhesive 502 is a semi-solid (e.g., gel) Pressure Sensitive Adhesive (PSA) such that the printable adhesive 502 adheres to the surface of the release liner 520 and remains relatively stable in the dispensed shape. It should be understood that the printable adhesive 502 is formulated to be dispensable by, for example, a screen printing process or by dispensing jets or needles, which may be referred to generally as nozzle dispensing. In some embodiments, the printable adhesive 502 is dispensed in a liquid state. The liquid adhesive may have sufficient viscosity to prevent the adhesive from flowing out of the dispensed shape while not being so viscous that the liquid adhesive cannot flow through the dispensing apparatus (e.g., a screen or nozzle).

In some embodiments, the printable adhesive 502 comprises a one-component adhesive. The printable adhesive 502 may be formulated to be dispensed in a first state and then activated using, for example, heat, UV light, a chemical catalyst, or some other activation method. In other embodiments, the printable adhesive 502 may be, for example, a two-component adhesive.

In some embodiments, the release liner 520 is a coated paper product. The base substrate of the paper is typically coated on one or both sides with a polymer or silicone based material. The coating aids in peeling the printable adhesive 502 from the release liner 520. In some embodiments, the release liner 520 may have additional layers or coatings. For example, the coating may be further coated with a second material, such as a thin layer of adhesive or a chemical designed to alter the tackiness or surface characteristics of the release liner 520. In other embodiments, the base substrate of the release liner 520 may be a material other than paper. For example, the release liner 520 may be made of a polymer. The polymer sheet may be formed to a desired thickness, such as by rolling under the application of heat and pressure, and then die cut into a desired shape.

In some embodiments, the printable adhesive 502 is dispensed on a flat rectangular section of the release liner 520 that defines the extent of the annular shape. Subsequently, the shape 510 may be cut from the dispensed portion of the adhesive 502 using, for example, a die cutter or other process. It will be appreciated that while the waste of the release liner remains the same as the technique highlighted in figure 1, the amount of wasted adhesive is significantly reduced.

In other embodiments, the release liner 520 may be shaped similar to the dispensed shape of the printable adhesive 502. In other words, the release liner 520 may have a shape that conforms to a circular shape (e.g., a closed curve of a circular, elliptical, or rectangular geometry). Thus, the amount of release liner 520 discarded as waste during subsequent die cutting or adhesive application steps may be reduced. However, it will be appreciated that such shapes are difficult to manufacture as release liner materials. For example, paper is produced in roll form or cut into flat sheets of paper, rather than being formed into the endless shape discussed above. Thus, the loop shape will likely be cut from a roll or rectangular sheet, producing similar waste paper in earlier manufacturing processes. However, paper waste from earlier steps can be more easily recycled and reused in an environmentally friendly manner than recycling release liners in subsequent steps, where the paper has been treated with paint or chemicals and adhesive has been dispensed on the release liner. Further, if the paper substrate is cut into a shape before the coating is applied to the paper substrate, the manufacture of release liner material can reduce the amount of coating raw material used to make the release liner in a loop shape. Further, in some embodiments, the release liner may not include a paper-based article, so there may be some release liners where the material may be directly formed or manufactured into an annular shape. For example, the polymer product may be formed directly into an annular shape, possibly via a molding process, onto which the coating is applied and the adhesive is subsequently dispensed. Such methods may further reduce waste by minimizing the amount of material used for the release liner.

It should be understood in fig. 5 that the amount of printable adhesive 502 dispensed is greater than the amount of printable adhesive 502 applied to the surface of the portable electronic device 300 in the shape 510. By dispensing the additional printable adhesive 502 to the release liner 520, the accuracy of the features of the shape 510 is controlled by the subsequent die cutting process, rather than the accuracy of the screen printing or dispensing process. Also, in some embodiments, the printable adhesive 502 is to be applied to a surface in the portable electronic device 300. The size of such surfaces may be relatively small. For example, the width of the flange 412 may be in a range of less than one millimeter to several millimeters. Further, the surface may include features having dimensions in a range of several mils to tens of mils. For example, the width of the shape 510 may vary around the perimeter of the annular shape, varying from, for example, 50 mils to 30 mils in width to conform to features in the surface. Those transitions may include a gradual change accompanied by a sharp change or associated with a curved transition between two widths. Features in the surface may be designed to accommodate components included in the portable electronic device, such as electronic components, flexible cables, antennas, brackets, fasteners, and the like.

The accuracy of the screen printing process may be limited by the size of the cells in the screen. As used herein, a unit refers to a negative space between fibers or threads interwoven in the mesh of a screen through which the printable adhesive 502 may flow when applied to the release liner 520. The spacing and size of the cells determines the accuracy of the features in the printable adhesive 502 that can be dispensed onto the release liner 520. Typical cell sizes may vary from about one mil to tens of mils. While smaller cell sizes may improve the accuracy of the screen printing process, viscous fluids may be more difficult to press through the smaller cells. The viscosity and chemical composition of the printable adhesive 502 may limit the minimum cell size that can be used with a screen printing process, thereby limiting the accuracy of the printed shapes 510 achieved with the screen printing process.

In some embodiments, the die cutting process can create more precise features in the dispensed printable adhesive 502 than can be achieved with the screen printing process alone. In other embodiments, the screen printing process is more accurate than the die cutting process. For example, features formed via the shearing mechanism of the mold may be less precise due to the printable adhesive 502 adhering to the mold or deforming when cut. The die cutting process can be particularly problematic where the features are extremely small (e.g., less than a millimeter in width). In such embodiments, the dispensing step may be adjusted to dispense the printable adhesive 502 onto the release liner 520 in the final shape 510, thereby omitting the subsequent die cutting process.

Similarly, other dispensing techniques, such as dispensing the printable adhesive through a nozzle, jet, or needle, may be less accurate or more precise than the die cutting process. Where the dispensing technique is less accurate than the die cutting process, the printable adhesive 502 may be dispensed in a first shape that includes edges that are larger than the final shape 510 formed during the die cutting process. Where the dispensing technique is more accurate than the die cutting process, the printable adhesive 502 may be dispensed in the final shape 510 and the die cutting process may be omitted.

In some embodiments, the die cutting process may be more efficient if combined with the cooling process. Prior to placing the printable adhesive 502 into the die cutter, the printable adhesive 502 on the release liner 520 may be cooled to lower the temperature of the printable adhesive 502 and make the printable adhesive more brittle and/or less tacky. These characteristics may improve the results of the die cutting process.

In some embodiments, dispensing techniques may be used to dispense adhesive at different points within the shape at different thicknesses. For example, multiple layers of the adhesive may be accumulated by applying multiple layers of the adhesive sequentially with different screens. Alternatively, the nozzle dispensing process may be performed by accumulating multiple layers of adhesive in a particular location via multiple passes of multiple passes. This may be useful in the following cases: the geometry of the mating components is non-uniform or flat such that the distance between a surface on a first component (e.g., a housing) and a surface on a second component (e.g., a display assembly bracket) is not uniform at all locations of the surfaces when the components are joined.

Fig. 6 illustrates a component 600 used in manufacturing the portable electronic device 300, according to some embodiments. The component 600 is similar to the component 500 except that the printable adhesive 602 is dispensed onto the release liner 620 in a shape 610 that conforms to the one or more surfaces of the portable electronic device 300 to which the printable adhesive 602 is to be applied.

It should be understood that the die cutting step may be omitted, as the die cutting step is not required to form the annular shape 610 in the printable adhesive 602. Further, it should be understood that the release liner 620 is illustrated as also having a generally annular shape, but the annular shape of the release liner 620 may have a uniform width along the perimeter of the annular shape. The release liner 620 may be manufactured prior to dispensing the printable adhesive 620 thereon to remove a central portion of the release liner 620. Alternatively, the release liner 620 may be initially manufactured in an annular shape (e.g., by a molding process, an extrusion and cutting process, etc.). It should be understood that in other embodiments, the release liner 620 is a rectangular shape that bounds the annular shape 610 and includes a material that fills the interior space of the annular shape 610, similar to the release liner 520 shown in fig. 5. However, even in these embodiments, the adhesive 602 may be printed to be dispensed on the release liner 620 in a shape 610 to be applied to the one or more surfaces of the portable electronic device 300.

The shape 610 of the printable adhesive 602 follows a path characterized by a continuous closed curve that forms a loop. The shape 610 also completely surrounds the area of the release liner 620 where no printable adhesive is dispensed and has a width that varies along the path. The shape may include features, such as feature 612, characterized by a transition from a first width at a first point in the path to a second width at a second point in the path. Notably, the width 614 of the shape refers to the distance across the printable adhesive 602 at a particular location of the path in a direction perpendicular to the path.

Fig. 7 is a flow diagram of a method 700 for applying a ring-shaped printable adhesive to a surface of a portable electronic device, according to some embodiments. At step 702, a release liner is provided. The release liner may be rectangular in shape and size to conform to the extent of one or more surfaces of the portable electronic device. In other embodiments, the release liner may have a shape that substantially conforms to the shape of one or more surfaces of the portable electronic device.

At 704, the printable adhesive is dispensed in a shape onto a surface of a release liner. The shape defines a central region on the surface of the release liner characterized by the absence of the dispensed printable adhesive in the central region. In some embodiments, the width of the printable adhesive along the path is substantially less than the width of the central region. For example, the distance between two edges of the printable adhesive across the central region may be 50 to 70 millimeters, which corresponds to the distance between the surfaces of the flanges formed around the opening in the housing of the portable electronic device, while the width of the printable adhesive may be less than a few millimeters. In some embodiments, the width of the printable adhesive varies along the path to conform to one or more features formed in the surface of the portable electronic device.

At 706, optionally, the adhesive and release liner may be cut via a die cutter. The die cutting process may change the shape of the adhesive to a desired shape to be applied to the surface of the portable electronic device. The desired shape may still be generally annular in shape, but may include at least one feature, such as a transition between a first width and a second width in the dispensed printable adhesive. The features may be small, such as features demonstrated in sizes of several to tens of 0.001 inches. In some embodiments, a cooling step is performed prior to the die-cutting step, in which the adhesive on the release liner is cooled to a desired temperature prior to being die-cut. The cooling step may increase the brittleness and/or decrease the tackiness of the adhesive and improve the accuracy of the cut edge of the printable adhesive resulting from the die cutting process.

At 708, a printable adhesive is applied to a surface of the portable electronic device. In some embodiments, the printable adhesive may be applied by applying pressure to the back surface of the release liner while the printable adhesive contacts the surface of the portable electronic device, and then removing the release liner, thereby leaving the printable adhesive on the surface of the portable electronic device. In some embodiments, the printable adhesive is applied manually. In other embodiments, the printable adhesive is automatically applied by an application robot or other automated assembly device.

Fig. 8 illustrates a technique for dispensing printable adhesive directly onto a surface of a portable electronic device 800, in accordance with some embodiments. In some cases, the surface of the portable electronic device 800 facilitates printing the adhesive directly onto the surface relative to the release liner. For example, if the surface is a flat surface on top of the housing 302, the adhesive 412 may be dispensed directly onto the surface of the portable electronic device 300 via a screen printing process. Alternatively, in the case where the surface is recessed below the top surface of the housing 302, a robotically controlled nozzle may be used to dispense the adhesive directly onto the surface.

As shown in fig. 8, a nozzle 850 connected to a robotic arm 860 may be controlled to move along a path defining the shape of the printable adhesive 810 dispensed on the surface 812 of the housing 802 of the portable electronic device 800. The shape may also include at least one feature, such as a transition between different widths of the annular shape along different points on the closed path corresponding to the shape. The nozzle may move along the path and the printable adhesive 810 may be dispensed from the nozzle. The robotic arm 860 controls the position of the nozzle, and an element of the nozzle is activated to dispense a droplet of printable adhesive 810 at that position. The nozzle may be moved around a path to deposit droplets in the shape of the printable adhesive 810 dispensed on the surface 812 of the housing 802.

Various aspects, embodiments, implementations, or features of the described embodiments may be used alone or in any combination. Various aspects of the described implementations may be implemented by software, hardware, or a combination of hardware and software. The embodiments may also be embodied as computer readable code on a non-transitory computer readable medium. The non-transitory computer readable medium is any data storage device that can store data which can thereafter be read by a computer system. Examples of non-transitory computer readable media include read-only memory, random-access memory, CD-ROMs, HDDs, DVDs, magnetic tapes, and optical data storage devices. The non-transitory computer readable medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art that the embodiments may be practiced without the specific details. Thus, the foregoing descriptions of specific embodiments are presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the described embodiments to the precise form disclosed. It will be apparent to those skilled in the art that many modifications and variations are possible in light of the above teaching.