Patent Application
20240324760
The present invention relates to brushes and has particular application to paint brushes.
Paintbrushes for the application of coating, paint and varnish are commonly known objects. They generally include a handle member interconnected to a bristle-carrying head, upon which are arranged a plurality of bristles. A junction between the handle member and the bristle carrying head is commonly further secured and covered by a collar, wherein the collar is fitted around the base of the bristle-carrying head and part of the handle member by such means as adhesives and/or screws to fix brush-head and handle together in a permanent assembled state. The present invention relates to paintbrushes comprising substantially standard paintbrush elements (brush head, ferrule and handle). As opposed to “permanently assembled” paintbrushes, the present invention deals specifically with paintbrushes of replaceable or interchangeable brush-heads and the significant challenges in obtaining well functioning removable connection between brush-head and handle of such. Relatively low precision in manufacturing of components makes it very challenging to obtain a uniform fit and removable connection between substantially standard paintbrush components (e.g. brush-head and corresponding handle) that is both sufficiently tight and sufficiently loose to provide good and consistent user functionality in the end product. Through inclusion of certain new and innovative low-complexity features, the present invention solves issues of connection between brush-head and handle not sufficiently solved in known prior art. Some relevant background art includes:
US2006000042A: The basic concept of a brush-head removably connected to a handle is known through this document. It describes a corner brush comprising a handle and a brush-head, the handle adapted in shape to fit with the angled brush-head to form a removable connection between the two. The document further describes a “click lock-in mechanism” between an aperture in the brush-head and a corresponding protrusion in the handle to prevent the brush-head from sliding out of its connection with the handle. Aspects of precision, tolerances and fit between handle and brush-head are not addressed, nor the expected implications of such on functionality of the end-product (e.g. “slack” in the connection).
WO2019083425A describes a relatively complex design, where a moulded plastic “bristle head cassette” of intricate details can be removably connected to a handle. In addition to basic principles of connection between brush-head and handle (i.e. “corresponding shape”) as also known from prior art US2006000042A, the document provides different concrete technical solutions of “Snap-fit locking” through the inclusion of ridges, grooves, protruding edges (84) or “other suitable connection means (26)” in the connector/ferrule and in the handle, together forming “snap-in arca(s)” (85) capable of receiving the cassette collar (20) to lock this into position. The document further describes a foam or rubber insert (50) configured for insertion into the cassette collar (20), through a pattern of ribs in the cassette collar, to provide a permanent cavity within “the plurality of bristles” capable of holding an amount of paint to increase paint capacity of the brush and support even distribution of paint onto a surface. Such permanent insert is a typical feature on most conventional brush-heads, although the insert is typically made from wood instead of rubber/foam. The insert described in the document plays no role in the connection mechanism between handle and brush-head, nor does the document indicate any intention of repeat connection/disconnection between insert and cassette.
US20200170396A1 describes a paintbrush comprising a conventional handle in combination with an unconventional “brush-head” referred to in the document as the “body”. Said body being made from two elements: a flat fabric folded and joined along its edges to form an empty “pocket” displaying one opening, said pocked having a hard interior surface and a soft velutinous exterior surface, the latter surface being capable of distributing paint onto a surface. The second element of the “body” constitute a semi-rigid insert (e.g. a block of foam material) adapted in shape to be inserted into and fill said empty pocket, supposedly so to provide support to the otherwise empty pocket. Friction is further mentioned as one mean of keeping the insert in place within the pocket. It is further described how the handle with the addition of a ferrule is positioned coaxially with the complete “body” and joined to this to scale the semi-rigid insert into the body safely keeping the insert in place within the body. The semi-rigid insert plays no direct role in the connection mechanism between body (brush head) and handle. The invention indicates no intention of a removable connection between body and handle of the paintbrush, and no intention of the body (brush-head) being removable/replaceable. Permanent means of fixture between elements, such as adhesives, nails and tape, are however specified throughout the document.
U.S. Pat. No. 3,386,119 describes paintbrush comprising a handle and a conventional brush head (bristles bundled together by a ferrule), and an alternative mean of fixing these permanently to one another by the use of a special expanding foam resin. The main objective of the invention is to provide a paintbrush that in its ready assembled state is free from empty space within the ferrule, to prevent solvents, water and other liquids to seep into the seams and openings in the ferrule to accumulate therein over time. Said objective is addressed by using a special type of expanding foam resin that in addition to permanently bonding handle to brush-head also expands to fill in any empty space in the ferrule, eventually hardening to a rigid closed cell foam material. The expanding property as well as rigidity and light weight of the particular type of resin/foam (“rigid closed cell formulation”) seems to be a main feature of the invention. Prior to curing it is resinous, but during expansion and curing the foamed material hardens to a degree where it firmly anchors handle to brush-head.
WO2009125022A—
Given proper cleaning after use, paintbrushes can be used numerous times. But after time the bristles will wear down to an extent that they will not function optimally. The paintbrush, comprising both handle and head, will then be discarded and replaced by a new paintbrush. Whereas a brush-head has a very limited life span due to deteriorating functionality of the bristles, a handle member is much less affected by wear thus potentially having a substantially longer life span than the brush-head. The handle member of the paintbrush represents a substantial amount of raw material as well as energy used in its production, and despite its potentially long life span it ends up being discarded as soon as its attached brush-head is worn down. This leads to the loss of valuable resources that could have been exploited to a much greater extent. A paintbrush with a replaceable brush-head, i.e. a removable connection between brush-head and handle, addresses this issue in allowing the user to discard a worn down brush-head while keeping the handle for further use with a new brush-head. It also allows for swift changing of brush-heads when switching between different colour paints using the one and same handle. Selling handle and brush-head as separate parts will optimize the life span of each, and at the same time provide a lower cost solution to users by enabling purchase of only the single part they need instead of having to buy both parts combined.
The present invention provides a well functioning paintbrush, comprising a brush-head removably connected to a handle to allow for easy repeat connection and disconnection of the brush-head from the handle without the need for tools or modification of any of the two said parts. It is critical that the connection and disconnection between the two is very swift and easy in order to provide acceptable user functionality, yet at the same time the connection must feel sturdy and safe. Imperfections in manufacturing as well as tolerances makes consistent and sufficiently tight fit a main challenge sought solved by the present invention through careful inclusion of soft friction enhancing cushioning material in the connection between handle and brush-head providing a low-tech and low-complexity solution to said challenge. The level of precision required for acceptable functionality is particularly difficult to achieve in handles machined from hard materials such as wood.
The unique and very specific properties of soft cushioning material (such as certain types of foam, felt and similar) do address some specific and challenging technical issues related to paintbrush manufacturing today, as does it solve critical requirements in terms of user experience necessary to meet in order to achieve a commercially successful end-product.
Taking into account limitations in commercial paintbrush manufacturing today it is claimed that the present invention, through innovative use of soft cushioning material, addresses significant issues not sufficiently solved in current prior art.
The vast majority of paintbrushes in the market today comprise a metal ferrule fixed to a handle of either rigid plastic or wood. Although relatively tight production tolerances are achievable in plastic moulding, the precision in conventional high-speed production of brush heads (metal ferrule wrapping, bristle insertion and epoxy casting) is at a completely different level with substantially looser production tolerances. Current state of production technology makes it thus unrealistic to mass produce parts (standard design brush-head and handle) with a sufficiently tight and uniform fit to provide a sturdy and well functioning end product without the use of permanent means of fixture between brush head and handle, such as spikes, adhesives or clamping. In case of wooden handle paintbrushes, both loose production tolerances as well as the dimensional instability of wood-expansion and contraction due to ambient conditions of moisture and temperature-adds further to this problem. As a consequence of these tolerance issues, a batch of mass produced brush heads and a batch of mass produced handles to fit, will provide both paintbrushes of relatively tight fit (e.g. the largest handle paired with the smallest brush head) and also paintbrushes of a very loose fit (e.g. the smallest handle paired with the largest brush-head). This, of course, is a significant issue in terms of the commercial value of the end-product: “refill brush-heads” removably connected to handle. This span in size variations due to production tolerances cannot be fully “absorbed” by any conventional material used in standard paintbrushes today-even “soft” polymers commonly used in plastic handle moulding do not provide a sufficiently high degree of flexibility (repeat compression/expansion) to work well across the relevant range of size variations. In terms of user functionality, even a slightly loose fit/slack or a too tight fit between brush head and handle will have a devastating effect and ultimately compromise the overall user experience of the end-product.
By inclusion of a soft friction enhancing material in/around the connection area between brush-head and handle, the present invention fully overcomes these issues. Due to its particularly high flexibility in terms of compression/expansion as well as ability to quickly restore to its original state again and again, said cushioning material is capable of working across the whole range of size variations (handles and brush heads) to ensure a uniform and sufficiently sturdy connection between brush-heads and handle, both on “loose-fit components” (handle and brush-head) and “tight-fit components”.
The invention further seeks to provide a functional brush-head designed to require an absolute minimum of materials and resources in production. A particularly important objective of the invention is to ensure that an absolute minimum of complexity and materials is included in the short-life-span brush head, and instead incorporate necessary complexity and materials into the handle with its long life span.
In line with the important global focus on design for recyclability, the invention also seeks to provide a brush-head of such material composition that it is suitable for efficient recycling in existing recycling streams, with a minimal loss of raw material during the process. The invention addresses this by a design that promotes clear and easy disassembly and separation of the paintbrush into a few different uniform components for separate recycling.
A final important objective of the invention is to provide a functional paintbrush configured from parts and adapted for processes available in current standard production lines, enabling low-energy- and low-cost manufacturing of the invention without the need of high investments in new technology and processes.
A paintbrush comprising two separate parts removably connected to each other, “removably connected” to be understood as the opposite of “fixedly connected/attached”, i.e. the two main parts, brush-head and handle, being connected to one another in such a way that the connected parts can easily and very swiftly be separated from one another and put together again without the need of tooling and/or without the need to modify any of the two parts such as by for example removing or manipulating fasteners or devices, and where repeat disconnection and connection of the two parts do not notably deteriorate the strength of connection between the parts when in a connected state.
The brush-head comprising a plurality of bristles fixed together in one end by means of hardened adhesive or similar to form a bundle or brush, the base portion of the brush comprising at least the hardened adhesive holding the bristles extending freely away from said base portion, the bristle-holding base portion being further covered and secured by a collar member fitted tightly around the base portion of the brush to form a cylinder, the cylinder extending lengthwise, from the base portion, in the opposite direction to the bristles, to form a first closed end of the cylinder and a second open end of the cylinder and an open cylindrical volume confined between the wall(s) of the cylinder itself and the base portion of the brush, said open volume being capable of receiving a handle corresponding in shape and size to said volume, inserted through said open end by non-rotational sliding into said volume to connect with the brush head. Such open volume included in the brush-head, adapted to receive and connect to a handle, is in the description of the present invention further referred to as the “connection cavity”.
A brush-head according to the present invention may include an additional third member, the intermediate insert. Said intermediate insert being characterized by having its own “connection cavity” substantially corresponding in shape to the cylindrical volume of the collar, so that when attached to the collar the intermediate insert presents the “connection cavity” extending within the volume confined by the collar walls, said connection cavity of the intermediate insert protruding inwards from the open end of the collar and towards the base portion of the brush. The circumference of the general cylindrical shape of an intermediate insert's connection cavity is generally smaller than that of the collar, so that the smaller connection cavity of the intermediate insert fits within the cavity formed by collar walls and base portion. Such intermediate insert is fixedly attached to either the collar or the base portion of the brush to form part of the brush-head and serve function as its connection cavity.
Regardless of whether the brush-head includes an intermediate insert or not, the ready brush-head presents a connection cavity capable of receiving and forming a removable connection with the handle. Said connection cavity is defined by side-surface(s) and base-surface(s) confining an empty volume, the cavity, being accessible through a top opening. In preferred embodiments of the invention Side-surface(s) extend substantially perpendicular to the base-portion of the brush. The walls of the collar together with the base portion of the brush will also, on embodiments of the invention without intermediate insert, in themselves together constitute side-surface and base-surface of a fully functional connection cavity.
The invention further comprise a handle member, such in form that it is capable of forming a removable connection with the brush-head. The handle has two end portions, a Distal portion and a Proximate portion, said end-portions being positioned substantially opposed to one another on the handle member. In its preferred embodiment, the Proximate portion of the handle has a substantially cylindrical shape, typically oval-like or rectangular-like, corresponding in size and shape to the connection cavity so that when handle is slid into said connection cavity, the proximate portion of the handle will extend within the open volume of the connection cavity ensuring frictional contact between the surface of the handle and the surface(s) of the connection cavity.
In terms of user functionality it is absolute key to achieve a sufficiently tight fit in the connection between brush head and handle on every paintbrush produced. Even small deviations in size and shape of connection cavity and handle may have a notably negative impact on the functionality of the paintbrush. To achieve a consistent result of good fit between the handle and the connection cavity, providing a connection between the two that feels safe and sturdy to the user, a softer friction enhancing cushioning material can be applied as an intermediate layer between handle surface and connection cavity to significantly reduce any movement between the two when in a connected state. A tight fit between handle and brush-head, without notable movement between the two during use, is of utmost importance for the perceived quality and functionality of the paintbrush. The inclusion of soft cushioning material also eliminates any unwanted click-sounds that might otherwise have arised during use of the paintbrush, from movement (collision) between handle and brush-head joined through a loose-fit/high-slack connection between handle and brush-head. Said cushioning material may be applied onto the proximate portion of the handle, or on the inner surfaces of the collar/connection cavity, or on both. Either in only certain critical areas, or covering the entire surface(s) of proximate portion/connection cavity. The mounting of self-adhesive patch(es) of such cushioning material in certain critical areas of the handle's proximate portion, or in certain critical areas of the brush-head's collar, is one relevant method of application, and such can be applied either during manufacturing of the handle or brush-head, or supplied to the end-user as separate self-adhesive pieces of material adapted in shape and size to be manually applied onto the proximate portion of the handle by the end-user himself. Foamed materials such as for example neoprene, or felt and similar fabrics with good cushioning properties, can all be suitable options as friction enhancing material. The surface of the connection cavity and/or the surface of the proximate portion of the handle may also for example be coated, in full or in certain areas, with softer friction-enhancing substance, such as rubberfoam, fibre flocking or similar, for an increased frictional connection and cushioning between handle and brush-head. Such friction enhancing substance or material may be applied as liquid- or powder-coating or as patches or laminates of solid material. A collar and/or connection cavity formed from a pre-flocked or pre-felt-laminated sheet of metal could be one method of achieving a friction enhanced surface according to the invention. Likewise would a ready formed handle provided with a felt-patch attached to the surface of its proximate portion, or a handle spray-coated with or dipped into a suitable friction enhancing substance during or post forming of said handle. The surface of the connection cavity and/or the surface of the proximate portion of the handle may also be mechanically formed with an uneven surface rather than a smooth and include such three dimensional structure as ribs or bumps for an increased frictional attachment between handle and brush-head during the sliding connection and disconnection of these.
The invention exploits the different material properties of the handle, the connection cavity and the intermediate layer of soft cushioning material and how these can act together in balance to achieve great functionality of the paintbrush. Whether the cushioning material is applied onto the handle itself or onto the connection cavity, it will when handle and brush-head are assembled for use, form an intermediate layer between handle surface and the surface of the connection cavity. This sandwich structure might comprise three segments of categorically different material properties (especially in terms of density, rigidity and cushioning) to provide a fine-tuned balance of both rigidity and flexibility necessary to provide optimal, uniform and durable functionality of the paintbrush: A typical such “sandwich” would comprise a substantially rigid or semi-rigid segment (the connection cavity) adding support in the connection between handle and brush-head, followed by a cushioning segment of extraordinary flexing ability (quick substantial compression and ability to quickly revert to original shape again and again), followed by yet a rigid or semi-rigid segment (the handle surface) needed for compression support and a sufficiently rigid connection between brush-head and handle. The cushioning segment might have a categorically different density and cushioning ability than the other two segments, and materials capable of repeat manual compression down to ¾- 1/10 of their original thickness could be particularly suitable options and often necessary in order to “absorb” low precision in the manufacturing of the different paintbrush components, i.e. handle, ferrule, brush-head. As rigidity and cushioning are typically two conflicting or contradictory properties in a material, the rigidity required from a material suitable for a functional handle would typically not have sufficient cushioning ability to work well as a cushioning material according to the invention. And, the other way around, the cushioning ability required from a material suitable for a functional cushioning layer according to the invention, would typically not have sufficient rigidity to work well as a paintbrush handle, hence the three segment sandwich, the middle segment having a categorically lower density than the two others, becomes a solution. Cushioning ability suitable for a functional cushioning layer may be found in material categories such as f.ex. foam materials, particularly so flexible foams, certain kinds of fabric/textiles and natural and synthetic fibre materials, to mention some. Typical for these are their flexibility combined with low density, i.e. the overall volume of the unmodified material body includes a lot of air that is easily “squeezed” out of the material by manual pressure to substantially reduce the overall volume of the material, and further their ability to quickly “absorb” air back as soon as compression is released so that the material reverts back to its substantially original volume/shape.
In embodiments of the invention where the friction enhancing cushioning material is applied onto the proximate portion as patch(es) or laminates of solid material, the proximate portion of the handle may have, on its side surface(s), a protruding edge encircling the proximate end surface. The edge can be in form of one continuous element, or several protruding elements positioned in line to form an “edge” or a “rim” circumfering the proximate end surface. Said protruding element(s) protrude(s) from the proximate side surface(s) of the proximate portion, and preferably protrude(s) in a primarily parallel plane to the proximate end surface. Such protruding edge will provide protection to the periphery of the cushioning material, preventing wear and tear from direct collision between any edge of the cushioning material and the top opening edge of the connection cavity during repeat connection of handle and brush-head.
Typical for conventional brushes today is a substantial empty gap between the proximate end portion of the handle and the base portion of the brush while in an assembled state. The handle is then typically fixedly attached to the collar by means of spikes, screws and/or adhesive, hence direct contact between handle and brush is not important for stability in the connection between the two. A preferred feature of the present invention is no or minimal empty gap between the proximate portion of the handle and the base surface of the connection cavity, this to ensure good contact between the handle and the brush-head. The absence of an empty gap between the two contributes to a stabile connection between handle and brush-head without the use of additional means of fastening, such as adhesive or screws which would have formed a fixed connection between the two instead of a removable connection as sought in the present invention.
A handle according to the invention may be formed from any material or combination of materials. In certain embodiments of the invention a handle assembled from two main members could be desirable. A First handle member would typically form the main grip of the handle, comprising the distal portion of the handle and extending in length further therefrom towards an opposite end of said first member, the “Connecting end”, said Connecting end being adapted to fit with and connect to a Second handle member. Such First handle member could typically be made from a conventional handle material of lower cost such as moulded plastic, composite or machined wood. A second member comprising the proximate portion of the handle is adapted to fit with and connect to the Connecting end of the first handle member so that when the two handle members are assembled they form a complete paintbrush handle, first handle member providing the main grip and second handle member comprising the proximate portion of the handle. Such Second handle member could typically be in form of a rigid metal or plastic piece, confining an open and empty volume or a closed and filled volume. In case of an open volume, said second member may be in form of a “cap” or a “ferrule” slid onto or wrapped around the connecting end of the first member. In embodiments of the handle where the first member is made from wood or similar hygroscopic materials of high dimensional instability, a two-part handle may be desirable as a second member made from a more dimensionally stabile material such as f.ex. non-hygroscopic metal or rigid plastic would, when the two handle members are assembled, constrain any dimensional change in the first handle member that may arise due to fluctuations in surrounding temperature and moisture. This would help to ensure a stabile tight fit between the proximate portion of the handle and the brush-head during connection and disconnection of these in different relevant ambient conditions. A two-part handle, as described above, would ensure at least an outer surface of the handle's proximate portion able to maintain its dimensions in all relevant ambient conditions.
One objective of the invention is to provide a paintbrush comprising a combination of components that can easily be assembled in standard automatic paintbrush assembly lines without notable change in existing tooling, machinery, procedures or production speed. A two-member handle may be beneficial in this regard, as application of friction enhancing cushioning material can be done on the “second handle member” as a separate part and in a separate process prior to final product assembly, ensuring minimal interference with already established standard procedures in both handle manufacturing and final product assembly. A Second handle member, e.g. in form of a moulded metal cap resembling the shape of a standard brush-head ferrule, could thus in a separate process be fitted with soft friction enhancing cushioning material in suitable area(s) (proximate portion), and later be supplied to any standard paintbrush assembly line for connection to a first handle member using the exact same standard automatic assembly methods that are used today for assembling a standard paintbrush handle and a standard brush-head by such means as adhesive, nails and/or similar. The first handle member would thus during production and assembly be processed as any other conventional paintbrush handle, and the second handle member would during assembly be processed as any conventional brush head-loaded, handled and joined to handle.
For improved stability in the connection between handle and brush-head, the side surface of the connection cavity may have at least one embossed/debossed area extending from its opening edge and towards its base surface. This embossed area will form a groove, preferably protruding away from the centre of the connection cavity. A suitable handle can be fitted with at least one “rib” of such suitable shape and size to correspond with and fit said groove as hand in glove so that when handle is slid into the connection cavity, the “rib” on the handle will also slide into its corresponding groove to form contact between the two. Preferably, such rib in the handle protrudes outwards from the rest of the handle surface. Such groove in the connection cavity interrupts also the opening edge of the connection cavity to form an outward protruding section in this to make room for a corresponding rib on the handle when handle is inserted into the connection cavity.
In certain embodiments of the invention, the above mentioned groove may be in form of a cut-out section rather than an embossed/debossed area, said “groove” still allowing a corresponding rib on the handle to slide into it. In embodiments where the groove is in form of a cut-out section instead of an embossed/debossed area, the corresponding rib on the handle may have a recess on each side so that when rib is slid into groove, the edges of the cut-out “groove” slides into said recesses to be held in position by these. The “rib” on the handle may be of any shape and size so long as it corresponds to the groove in terms of position when handle is inserted into connection cavity, and as long as it has a shape and size that fits to the groove in the brush head. The rib may thus be in form of one or several substantially aligned protruding elements f-ex. circular, rectangular or oval in shape.
A brush head according to the invention may preferably have one or more holes penetrating the collar walls to allow for easy hanging of the brush-head in store shelves, racks or other rigs meant for the appropriate and efficient display of brush heads in store.
Cellular materials and fibrous materials, natural or synthetic, such as for example soft and/or elastic foam- and sponge materials of open or closed cells, felt, flocking, various textiles such as pile material, are both material categories that are particularly suitable as soft friction enhancing material according to the present invention. Soft flexible corrugated- or honeycomb sheet materials are other examples of cellular materials that could work well as a cushioning material, as the empty space in between the material structure allows a high level of cushioning effect.
In some variations of the invention, it could be desirable that the soft friction enhancing material is applied onto the proximate portion of the handle or onto the surface of the connection cavity or on both in such a way that when handle and brush head is in a connected state, the cushioning material lines the entire or at least the substantial portion of the connection cavity's opening edge, leaving few or no visible gap(s) between the opening edge of the connection cavity and the handle itself. Gaps between said opening edge and handle, if not blocked by soft cushioning material, would allow paint and/or water to seep freely through and into the connection cavity where it, in case of water might accumulate in the brush head to corrode the connection cavity and proximate portion of the handle, or in case of paint may stick proximate portion of handle and connection cavity of brush-head together making manual disconnection of brush-head from handle more difficult or even impossible. To have optimal function as a liquid block/seal, as herein described, the cushioning material should be of a type of no or very low ability to absorb liquid, preferably a material with water-/liquid-repellent properties. Silicon is one example of such a material. Even paint would have difficulties sticking to silicon. In order to increase the liquid repellency of any suitable cushioning material, the cushioning material could in itself be treated or lined with a thin coating or layer of a water repellent substance. Or parts of the handle could also be treated with liquid-/paint-repellent substance to prevent paint from sticking to it.
According to the present invention, the soft friction enhancing cushioning material can come in different forms and be applied to the proximate portion of the handle in different ways. Suitable cushioning material in form of a liquid solution can be sprayed onto the handle to form f.ex. a foam surface upon curing of the liquid, or flat pre-cut pieces of suitable cushioning material can be mounted directly and fixed onto the appropriate areas of the handle either by hand or machine. The cushioning material can however also come in form of a substantially tubular section adapted in shape and size to fit the proximate portion of the handle to provide this with a surface of soft friction enhancing cushioning material. Such tubular cushioning material may be from a flat piece of material assembled into a tubular shape, or it may be formed directly from pellets into a tubular shape by tubular extrusion, tubular knitting/weaving or similar tubular production methods. Such tubular section could very well be clastic so that it can easily be stretched onto the proximate portion of the handle, positioned correctly, and released by hand or machine to allow the elasticity of the tubular section to tighten the tubular material around the proximate portion of the handle to cover this in a tight manner. The proximate portion of the handle can also be treated mechanically, chemically or by surface coating/lining with adhesion- and/or friction enhancing element or matter (f.ex. sandpaper, sand or similar granules to produce a rugged sandpaper-like surface, or on the other hand a smooth rubbery surface) to enhance the frictional properties of its surface, i.e. increased friction, upon which the mere friction between the surface of the proximate portion of the handle and the tubular cushioning material provides a sufficient bond between the two, eliminating the need for additional fastening means such as adhesives to keep cushioning material and handle together during use of the paintbrush. Such removable connection between cushioning material and proximate portion, also means that the tubular cushioning material can be easily/manually removed from the handle and replaced with a new piece of cushioning material, which could be a desirable feature on a paintbrush in cases where the cushioning material has been damaged or deteriorated due to wear and tear. Appropriate cushioning material, according to the invention, might also come in form of separate pre-formed patch(es) or label(s) adapted in shape and size to be integrated with—and bonded to the proximate portion of the handle during moulding of this, a method commonly referred to as “insert-moulding”. Insert moulding involves one or more separate pieces of suitable cushioning material, as further specified throughout the description of the present invention, being inserted into the mould prior to moulding of the handle, said piece(s) positioned precisely in the mould, the mould closed and plastic, or other mouldable material, being inserted under pressure to form the handle itself while at the same time bonding said cushioning material to the handle in a correct position. Another desirable method for producing a handle according to the present invention is “overmoulding”. In overmoulding, an appropriate cushioning material in fluid form would be moulded in correct position directly onto the rigid handle, in a same moulding sequence, immediately after moulding of the rigid handle, to make one unitary moulded handle comprising both materials—the rigid plastic and the soft cushioning material joined together. Insert-moulding and Overmoulding are two variations of “multi-component moulding” wherein the moulding sequence involves one or more injections of fluid material, single-shot or multi-shot.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20211252 | Oct 2021 | NO | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/NO2022/000005 | 10/17/2022 | WO |
