Paper Cap

Abstract

A cap (100) for closing a container and a corresponding method for manufacturing the cap (100) are described. The cap (100) has a spirally wound sleeve (101) including a first opening (105) and a second opening (104), the first opening (105) and the second opening (104) facing each other. The cap (100) further has a head disk (102) positioned to close the first opening (105) of the sleeve (101). The sleeve (101) is made of paper. The second opening (104) of the sleeve (101) has a reinforcing element (106), which is a structure extending into the sleeve (101).

Description

[Technical field]

[0001] The present invention relates to a paper cap for closing a container, in particular an aerosol can. Furthermore, the present invention relates to a method for producing a cap for closing a container. [Background technology]

[0002] Caps, in particular caps for aerosol cans, made from petrochemical plastics, in particular polypropylene or polyethylene, are known. Such conventional aerosol can caps are typically produced by manufacturing methods such as, for example, injection molding.

[0003] In general, the reusability or recyclability of conventional caps is rather low, and they are very energy intensive and cost intensive, so that most of the conventional caps are disposed of as residual waste in waste disposal sites or as fuel in waste incineration plants. Therefore, the CO2 balance and environmental compatibility of conventional aerosol can caps are poor. The CO2 balance is the balance of greenhouse gas emissions throughout the entire life cycle of a product for a given use and a given unit of use. Summary of the Invention

[0004] The invention is based on the problem of providing a sustainable cap for containers, in particular aerosol cans, which can be attached force- and form-fittingly and which is also recyclable, reusable or compostable.

[0005] The above object is achieved by the subject matter of the independent claims. Advantageous embodiments of the invention are set forth in the dependent claims.

[0006] According to a first aspect of the invention, a cap for closing a container is described. The cap has a spirally wound sleeve including a first opening and a second opening, the first opening and the second opening being arranged opposite each other. The cap further has a head disk arranged to close the first opening of the sleeve. The sleeve is manufactured from paper. The second opening of the sleeve has a reinforcing element, the reinforcing element being a structure extending into the interior of the sleeve.

[0007] According to another aspect of the invention, a method of making a cap for closing a container is described, the method comprising the steps of (i) helically winding a sleeve having a first opening and a second opening, the first opening and the second opening facing each other, (ii) positioning a head disk such that the head disk closes the first opening of the sleeve, the sleeve being made from paper, and (iii) providing a reinforcing element at the second opening of the sleeve, the reinforcing element being a structure that extends into the interior of the sleeve.

[0008] The sleeve may be a tubular, elongated, cylindrical, solid sleeve. In an exemplary embodiment, the tubular, elongated, cylindrical sleeve is characterized in that it has two openings, which are opposite each other along the longitudinal direction and, for example, form the upper surface of the cylinder. The sleeve may in particular form a rotationally symmetrical body, the axis of symmetry (central axis) of which runs parallel to the longitudinal direction. The sleeve, which corresponds to the side surface of the cylinder, may be uniform, i.e. the side surface is not provided with any other openings or cavities. Alternatively, there may be at least one other opening or cavities in addition to the two openings, which are opposite each other and may form the upper surface of the cylinder. The sleeve may have a diameter of 30 mm (millimeters) to 74 mm, in particular 35 mm to 65 mm.

[0009] In the context of the present invention, the "interior of the sleeve" refers to the internal volume enclosed in the lateral extension of the sleeve. The longitudinal or central axis of the sleeve is perpendicular to the radial direction of the sleeve.

[0010] In the context of the present application, the term "reinforcing element" can denote a full or partial circumferential bulge that extends from the side of the sleeve into the interior or internal volume of the sleeve and contributes to the reinforcement, mechanical strength and shape stability of the sleeve. Furthermore, since the reinforcing element extends into the internal volume and thus releasably connects, for example, with a receiving groove of the can, the reinforcing element is used as an attachment device of the cap to a compatible can, in particular an aerosol can. The reinforcing element can form an integral region of the sleeve or can consist of a separate element of a material different from the sleeve.

[0011] The reinforcing element may be a plurality of bulge segments that do not completely circumnavigate the interior of the sleeve, where the reinforcing element extends radially inwardly by 1%-10% of the diameter of the sleeve, or in addition to extending radially inwardly by 1%-10% of the diameter of the sleeve, the reinforcing element may also extend longitudinally inwardly by 5%-20% of the length of the sleeve.

[0012] In the context of the present application, the term "paper" denotes, for example, a flat material made of fibrous materials, especially of plant origin (e.g. cellulose, wood pulp and waste paper materials). Exemplary embodiments of "paper" include paper as well as cardboard and paperboard, which are differentiated on the basis of their mass per unit area according to DIN 6730. DIN 6730 states that paper has a mass per unit area of ​​7 g / m2. 2 ~225g / m 2 , and cardboard has a mass per unit area of ​​150 g / m 2 ~600g / m 2 , and the mass per unit area of ​​paperboard is 225g / m 2 In addition, the exemplary embodiment of "paper" may also represent a thin wood sheet or a cork sheet having a thickness similar to that of paper. Furthermore, paper may contain up to 5% foreign matter.

[0013] The sleeve according to the invention is produced in a spiral winding process, in which at least one sized paper web is wound around a stationary mandrel, partially overlapping or butting against one another, depending on the intended use and the strength requirements associated therewith. In this case, each sized paper web is a layer of the winding. During the spiral winding process, individual layers, several individual layers one on top of another or several individual layers one inside another can be wound. To provide the layers, the edges of the paper webs can overlap in the length direction of the sleeve, the overlapping areas of the paper webs being fixed, in particular glued, to one another.

[0014] The head disk may be formed from paper in one or more layers.

[0015] The cap according to the invention for closing containers has a good CO2 balance and environmental compatibility and is therefore used to reduce non-reusable waste. This is made possible by the fact that the cap is completely made of paper, i.e. both the sleeve and the head disk. The production of the paper cap by spirally winding a paper web results in a robust and durable cap that also keeps the can tight against aerosols or other fluids. Furthermore, the production of the cap from paper allows the cap to be adapted in terms of height, diameter and material thickness without great effort and cost and to be formed with a visual design, e.g. multicolored, or a tactile design, e.g. embossed. Small series of caps can thereby also be realized economically. Furthermore, the spiral winding technique allows the cap to be adapted in height, diameter and material thickness in a simple manner, since no complex adaptation work is necessary to the production equipment. Small series of caps can thereby also be realized economically. Furthermore, there is also the possibility of deforming the head plate by embossing in order to achieve certain visual or tactile effects. Additionally, the cylindrical portion may be specially machined to have visual, tactile, or application-specific modifications, such as grip grooves, to better facilitate fitting and removal of the cap.

[0016] According to another exemplary embodiment of the invention, the first opening has a bulge, in particular a flange (e.g. having a rounded cross section), which extends into the interior of the sleeve, and the head disk is coupled or fixed to the part of the bulge that extends into the interior of the sleeve.

[0017] The bulge can be a complete or partial circumferential bulge extending from the (inner) side of the sleeve into the interior or interior volume of the sleeve. A flange is a thickening or bulge that provides reinforcement of the folded edge of the sleeve by flanging, i.e. by folding the edge of the sleeve inwards.

[0018] The head disk and the flange are connected or fixed to one another, for example, by providing a material bond (gluing) and / or a pressure bond. An exemplary connection can be realized by applying an adhesive to the head disk and / or to the flange. In this case, the adhesion can be realized completely, i.e. along the entire mounting surface of the head disk on the flange, or in a point-like manner, preferably by three adhesive points. Furthermore, the connection between the head disk and the flange can also be realized by a press fit.

[0019] This exemplary embodiment has the advantage that it provides a stable attachment of the head disk to the flange, which reliably prevents the head disk from falling off or becoming displaced, thereby improving the resistance and longevity of the cap, and furthermore, the coupling or arrangement of the head disk to the part of the flange which extends into the sleeve has the advantage that the attachment of the head disk is inside the sleeve, i.e. in the area of ​​the sleeve which corresponds to the cylindrical volume of the sleeve, so that the attachment of the head disk can be protected from environmental influences, which also improves the resistance and longevity of the cap.

[0020] According to another exemplary embodiment of the present invention, the outer surface of the sleeve and / or the inner surface of the sleeve is provided with a synthetic or bio-based coating.

[0021] In the context of the present application, the term "outer surface" refers to the surface of the sleeve that is in direct contact with the surrounding area of ​​the sleeve and is therefore exposed to environmental influences. The term "inner surface" refers to the surface of the sleeve that is inside the sleeve. In another embodiment, the "inner surface" of the head disk that is inside the sleeve and / or the "outer surface" of the head disk that is in direct contact with the surrounding environment may also be provided with a synthetic or bio-based coating.

[0022] The outer or inner surface may be provided with a synthetic or bio-based coating, which is impermeable and which insulates, seals or encapsulates the paper sleeve layer. Exemplary embodiments of synthetic or metal-based coatings are thin plastic layers, e.g. made of PE or PP, or metal layers, e.g. aluminum foil.

[0023] In this case, the coating can also be colored. Exemplary embodiments of the bio-based coating are the following materials: cork, wood, wax, or bio-based plastics, such as PLA. In this case, the exemplary embodiments are not limited to the above-mentioned materials. The coating has a thickness / depth of less than 20% of the total weight of the cap, preferably less than 5% of the total weight of the cap, to ensure the recyclability of the cap.

[0024] This exemplary embodiment has the advantage that the resistance of the sleeve to, for example, grease, oil and water may be improved, thus improving the longevity of the cap.

[0025] According to another exemplary embodiment of the present invention, the sleeve comprises at least one inner layer and one outer layer, both of which are spirally wound.

[0026] The outer layer is the radially outermost paper layer and has an outer surface. The inner layer is the paper layer having an inner surface. A number of other layers can be disposed between the inner and outer layers.

[0027] By using a corresponding number of layers, the sleeve can be adjusted to any desired thickness, thereby increasing the strength and shape stability of the sleeve.

[0028] According to another exemplary embodiment of the invention, the reinforcing element at the second opening of the sleeve comprises a thickened area or bulge, which may be provided on the interior of the sleeve by flanging an end region of the sleeve, the flanged end region of the sleeve being radially compressed.

[0029] The end region of the sleeve at the second opening is the end region that is directly adjacent to the second opening of the sleeve and has the terminal edge of the sleeve. After flanging or folding the end region of the sleeve inward, there may be a cavity between the abutting layers after folding, or the layers may abut loosely. In order to achieve a better strengthening effect, a radial pressure can be applied to compress the abutting layers against each other.

[0030] This exemplary embodiment has the advantage that on the one hand a thickened area is provided which increases the shape stability of the sleeve or cap and on the other hand reduces the diameter of the cap inwardly near the second opening of the sleeve. By reducing the inner diameter of the second opening of the sleeve a firm and non-displaceable seating of the cap on the compatible can, in particular an aerosol can, can be ensured. For better attachment the can can have a corresponding receiving groove for the thickened area or bulge. The inner diameter of the bulge can be configured and adjusted in such a way that the filled can can be lifted by the cap alone without removing the cap from the compatible can.

[0031] The end regions or terminal edges of the sleeve define the axial ends of the sleeve.

[0032] The cut edge of the sleeve indicates the opening of the layers. If the layers end axially in the end region with an open cut edge, there is a risk that moisture will penetrate between the paper layers and the paper layers will come loose or expand. By flanging or folding the end region of the sleeve into the inside of the sleeve, the outer layer will surround the axial end of the sleeve, which will reduce moisture penetration between the layers of the sleeve. The cut edge is then inside the sleeve. The resistance and longevity of the cap can therefore be improved.

[0033] According to another exemplary embodiment of the invention, the reinforcing element at the second opening of the sleeve has a thickened area, which is provided by applying an adhesive, in particular a recyclable adhesive.

[0034] Recyclable adhesives are adhesives that are recyclable and / or have a low environmental impact. Exemplary embodiments of recyclable adhesives are the following materials: natural rubber, formaldehyde-free dispersion adhesives (PVAC sugar glue) and lignin-based polymer adhesives (LignoGlue).

[0035] This exemplary embodiment likewise has the advantage that a thickened area is provided which, on the one hand, increases the shape stability of the sleeve or cap, and, on the other hand, reduces the diameter of the cap inwardly near the second opening of the sleeve, thereby ensuring a firm and undisplaced seating of the cap on a compatible can, in particular an aerosol can. Furthermore, by applying an adhesive, the open cut edge of the sleeve at the second opening can be sealed, thereby providing protection against environmental influences, such as for example moisture in the air. Thus, the resistance and longevity of the cap can be improved.

[0036] According to another exemplary embodiment of the invention, the reinforcing element at the second opening of the sleeve has a thickened area, which is provided by folding the outer layer into the interior of the sleeve, so that the outer layer at least partially covers (at its axial end) at least one inner layer.

[0037] This exemplary embodiment likewise has the advantage that a thickened area is provided which, on the one hand, increases the shape stability of the sleeve or cap, and, on the other hand, reduces the diameter of the sleeve near the second opening of the sleeve, thereby ensuring a firm and undisplaced seating of the cap on a compatible can, in particular an aerosol can. Furthermore, when the outer layer at least partially covers at least one inner layer, by folding the outer layer into the inside of the sleeve, the lower cut edge of the inner layer near the opening of the sleeve is protected, thereby providing protection against environmental influences, for example the ingress of moisture from the air. Thus, the resistance and longevity of the cap can be improved.

[0038] According to another exemplary embodiment of the present invention, positioning the head disk includes the following method steps: (I) flanging a first opening of the sleeve, particularly with a round cross-section; (II) providing a head disk; and (III) coupling the head disk to a flange extending into the interior of the sleeve, particularly to a portion of the flange located within the sleeve.

[0039] According to another exemplary embodiment of the present invention, providing the second opening of the sleeve with a reinforcing element comprises a thickened region, the thickened region being provided by one of: (a) flanging the second opening, in particular with a round cross-section, followed by radially compressing the resulting flange, (b) arranging an adhesive, in particular a recyclable adhesive, in the second opening, and (c) if the sleeve comprises at least one inner layer and one outer layer, folding the outer layer of the sleeve, whereby the outer layer at least partially covers the at least one inner layer.

[0040] It should be noted that the embodiments described herein merely represent a limited selection of possible variations of the present invention, and therefore the features of the individual embodiments can be combined with each other in any suitable manner, so that the explicit variations herein should be considered as clearly disclosing a multitude of different embodiments to those skilled in the art. [Brief description of the drawings]

[0041] [Figure 1] 2 is a cross-sectional view of an embodiment of a cap according to the present invention; [Diagram 2] 2 is a side view of an embodiment of the cap of FIG. 1 according to the present invention. [Diagram 3] 2 is a cross-sectional view of a detail view of an embodiment according to the invention of a reinforcing element of the cap of FIG. 1; [Figure 4] 2 is a cross-sectional view of a detailed view of another embodiment according to the invention of a reinforcing element of the cap of FIG. 1; [Diagram 5] 2 is a cross-sectional view of a detail of a reinforcing element of the cap of FIG. 1 according to another embodiment of the invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] It is noted that in the following detailed description, features or components of different embodiments that are the same as or at least functionally equivalent to corresponding features or components of another embodiment are given the same reference signs, or reference signs whose last two digits are identical to the reference signs of the corresponding same or at least functionally equivalent features or components. In order to avoid unnecessary repetition, features or components that have already been described on the basis of the previous embodiments will not be described in detail in the following passages.

[0043] Furthermore, it is noted that the illustrations are schematic and not to scale.

[0044] It is further noted that spatial terms, such as "front" and "back," "top" and "bottom," "left" and "right," etc., are used to describe the relationship of one element to another element or elements as depicted in the figures. Thus, the spatial terms may be applied to orientations other than those depicted in the figures. However, since each depicted device, component, etc., when used herein, may assume an orientation that may differ from that depicted in the figures, it is understood that all such spatial terms refer to the orientation depicted in the figures for ease of description and are not necessarily limiting.

[0045] 1 shows a cap 100 for closing a container, in particular an aerosol can. The cap 100 comprises a spirally wound sleeve 101 including a first opening 105 and a second opening 104. The first opening 105 and the second opening 104 are opposite each other. Furthermore, the cap 100 has a head disk 102, The head disk 102 is positioned such that it closes the first opening 105 of the sleeve 101. The sleeve 101 and the head disk 102 are made from paper. The second opening 104 of the sleeve 101 has a reinforcing element 106, which is a structure that extends into the interior of the sleeve 101.

[0046] The cap 100 has an elongated cylindrical tubular sleeve 101 .

[0047] The sleeve 101 has a length a, a thickness or material thickness b, and a width c. The width c is defined as the distance between the outer surface 107 of the sleeve 101 in the radial direction RR, near the first opening 105 of the sleeve 101. The sleeve 100 is in particular a rotationally symmetric body with an axis of symmetry (central axis) running parallel to the longitudinal direction LR. The radial direction RR runs perpendicular to the central axis and intersects it. The length a is defined as the distance between the first opening 105 and the second opening 104. The thickness or material thickness b is defined as the distance between the radially inner surface 108 and the radially outer surface 107. In this case, the thickness or material thickness b of the sleeve 101 depends on the number of paper layers and the thickness of the paper layers. The sleeve 101 and the head disk 102 can consist of the same or different number of paper layers. In this embodiment shown in FIG. 1, the cap 100, ie the sleeve 101 and the head disk 102, has three layers, ie spirally wound paper webs.

[0048] The sleeve 101 further has a first opening 105 and a second opening 104. A flange 103 is placed directly in the first opening 105. A flange is generally used to reinforce the folded edge of a structure and is formed by folding the edge of the structure. This flange 103 has a circular cross-sectional shape that extends inward in a radial direction RR and also outward in a longitudinal direction LR. In other words, the flange 103 extends to an area corresponding to the cylindrical volume of the sleeve. The second opening 104 is located opposite the first opening 105, and the first opening 105 and the second opening 104 are the cylinder or the upper surface of the sleeve 101, respectively. After flanging or folding the end area of ​​the sleeve inward, there may be a cavity between the layers that abut after folding or the layers may abut loosely, as in FIG. 1.

[0049] The sleeve 101 is uniform, i.e. there are no other openings or voids in the side surface of the sleeve 101 besides the first opening 105 and the second opening 104. In another exemplary embodiment, the sleeve can be provided with at least one other opening, for example in the side surface or in the head disk. This has the advantage that water can flow out through this other opening, thus drying the head area of ​​the can, which may for example be left in the shower, and water corrosion of the valve support covered by the cap is prevented. This also prevents water attacking the cap with long-term action.

[0050] The head disk 102 is bonded to the flange 103. The head disk 102 can be completely or dot-bonded to the flange 103 by an adhesive, in particular a recyclable adhesive or adhesive material. Additionally, the head disk 102 can be attached to the flange 103 by a press fit.

[0051] The head disk 102 can be made from multiple layers of cardboard. The sleeve 101 can be made from spirally wound paper, cardboard, paperboard, thin wood sheets, or other thin-walled materials that can be processed as described.

[0052] A reinforcing element 106, which provides reinforcement, high strength and dimensional stability of the sleeve 101, is arranged directly in the second opening 104. Another embodiment of the reinforcing element 106 is shown in detail B in Figs. 3 to 5. The reinforcing element 106 is a structure, in particular a circumferential bulge, extending into the interior of the sleeve 101. In this case, the reinforcing element 106 extends inwardly in a radial direction RR, in particular by 1% to 10% of the width c of the sleeve 101, and inwardly in a longitudinal direction LR, in particular by 5% to 20% of the length a of the sleeve 101, and thus in an area corresponding to the cylindrical volume of the sleeve 101. In the embodiment shown in Fig. 1, the reinforcing element 106 is larger in the area on the inner surface 108 of the sleeve 101 than the diameter of the cap 100, which also ensures a firm and non-displaceable seating on a compatible can, in particular an aerosol can. In this region, the width d of the sleeve 101 near the second opening 104 is greater than the width e of the second opening 104, and the width c of the sleeve 101 near the first opening 105 is between width d and width e.

[0053] In this case, the cap extends by 0.5% to 2% of the width c of the sleeve 101 at the first opening 105.

[0054] Figure 2 shows a side view of an embodiment according to the invention of the cap 100 according to Figure 1. The cap 100 has a length direction LR and a radial direction RR, the radial direction RR being perpendicular to the length direction LR. The length direction LR in Figure 2 extends along the central axis.

[0055] FIG. 3 shows a cross section of a detail view B of an embodiment according to the invention of the reinforcing element 106. The reinforcing element 301 has a thickened area A, which extends into the interior of the sleeve 101. The thickened area A is provided by flanging or folding an end area, i.e. an area which is located directly at the opening of the sleeve 101 and has a cut edge of the sleeve 101, into the interior of the sleeve 101. In addition to the flanging of the end area into the interior of the sleeve 101, the flanged end area is compressed in a radial direction RR. In this case, the compression of the flanged end area is achieved by applying a compressive force outwards in the radial direction RR. Furthermore, a compression by combined thermal and mechanical compression with a counter guide, a so-called "thermo-mechanical compression", can be provided.

[0056] Fig. 4 shows a cross section of detail view B of another embodiment according to the invention of a reinforcing element 106 of the cap 100. The reinforcing element 401 has a thickened area A. The thickened area A extends into the interior of the sleeve 101. This can be achieved by precisely applying the adhesive with an adhesive nozzle. Furthermore, the thickened area A can extend both into the interior and outwardly of the sleeve. The thickened area A is provided by applying an adhesive, in particular a recyclable adhesive, which extends into the interior of the sleeve 101. A well recyclable adhesive, in this case an adhesive with good recyclability.

[0057] 5 shows a cross section of detail view B of another inventive embodiment of the reinforcing element 106 of the cap 100. The reinforcing element 501 has an area A at the second opening 104 of the sleeve 101. Area A is provided by folding the outer layer 503 around the free end of the inner layer 502 into the inside of the sleeve 101. In this case, the outer layer 503 at least partially covers the inner layer 502 with its inner surface, i.e. the outer layer 503 completely conceals the end area of ​​the inner layer 502 of the sleeve 101. In this variant, the cap can be held by friction-induced binding forces between the cap and the aerosol can.

[0058] It is added that the term "comprises" does not exclude other elements and that "single" does not exclude a plurality. Elements described in the context of different embodiments may also be combined. It is added that reference signs in the claims shall not be interpreted as limiting the scope of protection of the claims. [Explanation of symbols]

[0059] 100 Cap 101 Sleeve 102 Head disk 103 Flange 104 Second Opening 105 First Opening 106 Enhancement Elements 107 Outer surface 108 Inner surface 301 Enhancement Elements 401 Enhancement Elements 501 Enhancement Elements 502 Inner layer 503 Outer layer a Sleeve length b Sleeve thickness / material thickness c Width of sleeve near first opening d d Width of sleeve near second opening e e Width of second opening A Thick area B. Detail LR Length direction RR Radial

Claims

1. a spirally wound sleeve including a first opening and a second opening, the first opening facing the second opening; a head disk disposed to close the first opening of the sleeve, the sleeve is made from paper; the second opening in the sleeve having a reinforcing element; the reinforcing element is a structure extending into the interior of the sleeve; The sleeve includes at least one spirally wound inner layer and one outer layer; the reinforcing element having a thickened region at the second opening of the sleeve; The thickened region is provided by folding the outer layer into the interior of the sleeve, such that the outer layer at least partially covers the at least one inner layer and the outer layer covers the inner layer at the axial cut of the inner layer, thereby protecting the axial cut of the inner layer.

2. the first opening has a bulge; the bulge extends into the interior of the sleeve; the head disk is coupled to the bulge portion extending into the interior of the sleeve; The cap of claim 1.

3. The outer surface of the sleeve and / or the inner surface of the sleeve are provided with a synthetic or bio-based coating; The cap according to claim 1 or 2.

4. the reinforcing element has a thickened region at the second opening of the sleeve provided by flanging an end region of the sleeve into the interior of the sleeve, the flanged end region of the sleeve being radially compressed; A cap according to any one of claims 1 to 3.

5. the reinforcing element has a thickened area at the second opening of the sleeve provided by applying an adhesive; The cap of claim 1.

6. A method of manufacturing a paper sleeve, the paper sleeve having a first opening and a second opening facing each other, said method comprising: positioning a head disk to close the first opening in the sleeve; providing a reinforcing element at the second opening of the sleeve, the reinforcing element being a structure extending into the interior of the sleeve, The sleeve includes at least one spirally wound inner layer and one outer layer; the reinforcing element having a thickened region at the second opening of the sleeve; The method of claim 1, wherein the thickened region is provided by folding the outer layer into the interior of the sleeve, such that the outer layer at least partially covers the at least one inner layer and the outer layer covers the inner layer at the axial cut of the inner layer, thereby protecting the axial cut of the inner layer.

7. The step of positioning the head disk further comprises: flanging the first opening in the sleeve; providing the head disk; and coupling the head disk to the inwardly extending flange of the sleeve. The method according to claim 6.

8. The thickened region may be formed by flanging the second opening, followed by radially compressing the resulting flange; disposing an adhesive in the second opening; 8. The method according to claim 6 or 7, wherein the method is provided by one of the following:

Images