AU631435B2

AU631435B2 - Forming method of patterned coating

Info

Publication number: AU631435B2
Application number: AU57816/90A
Authority: AU
Inventors: Takahiko Hamada; Gorou Nagao
Original assignee: Nippon Paint Co Ltd
Current assignee: Nippon Paint Co Ltd
Priority date: 1989-06-27
Filing date: 1990-06-26
Publication date: 1992-11-26
Anticipated expiration: 2010-06-26
Also published as: CA2019844A1; EP0406667B1; KR910000250A; EP0406667A1; AU5781690A; KR0135274B1; DE69015900T2; DE69015900D1

Description

required).

Bemerkung. Beglaubigung der Unterschrift ist nicht benoetigt.

K. SasaKi 'id ii President of NIPPON P i:iQ Form COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952-62 COMPLETE SPECIFICATION

(ORIGINAL)

551435 FOR OFFICE USE: Application Number: Lodged: Class Int. Class

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0 0 Complete Specification Lodged: S" Accepted: Published: Priorily: Related Art: Narri of Applicant: Address of Applicant: Actual Inventor: s: Address for Service: TO BE COMPLETED BY APPLICANT NIPPON PAINT CO., LTD.

1-2, Oyodokita 2-chome, Kita-ku, Osaka, Japan TAKAHIKO HAMADA and GOROU NAGAO Care of R.K. MADDERN ASSOCIATES, 345 King William Street, Adelaide, South Australia, Australia.

Complete Specification for the invention entitled: "FORMING METHOD OF PATTERNED COATING" The following statement is a full description of this invention, including the best method of performing it known to me. us

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surface of the substrate becomes a continuous I-shape pattern having a relatively large width.

uas rronrolatt ist nur in normalen Faellen, in denen der/die Anmelder oder der/die Erfinder die Anmeldung(en) gemaess Paragraph 2 gemacht hat/haben, zu vervenden. Im Falle frug e .r "n e rhgn FORMING METHOD OF PATTERNED COATING ABSTRACT OF THE DISCLOSURE A method of forming a patterned coating upon a surface of a substrate is provided. A plurality of separated magnetic elements are arranged side by side forming an arrayed module of the elements. Then, the module is brought in close vicinity of the reverse side of the substrate. And then, magnetic paint containing powdery magnetic material is applied to the surface of the substrate to make a wet film thereon. Finally, the wet rilm is hardened through a baking or drying. A continuous pattern corresponding to the configuration pattern of the module appears on the surface of the substrate. Alternatively, a coated substrate may be introduced into a magnetic field while a wet film of magnetic paint is carried thereon.

i I J I i elements 67 and 68 of the module 69 are disposed such that the North magnetic pole of one element is positioned in the FORMING METHOD OF PATTERNED COATING BACKGROUND OF THE INVENTION This invention relates to a forming method of patterned coating upon miscellaneous surfaces, especially a method for illustrating various letters, characters, or figures upon a coated surface in a different tone of configuration from adjacent areas.

In order to illustrate miscellaneo'is patterns on a coated film, various methods have been proposed including; 0 a method of additional coating utilizing a masking template for covering a portion of a pre-coated surface; a method of o sticking colored sEheets or colored tapes on a pre--coated film; and a meth~d of embossing patterns on an under layer or substrate before a color coating.

However, these methods have specific drawbacks of the following: the masking template needs time-consuming sticking work and stripping work; a stepped irreguralities are produced between the first coating film and the second coating film; the patterns made by sheets or tapes tend to be erased within a short period; or embossilng patterns cannot render an >2 explicit configuration.

In Japanese Patent Public Disclosure No. 175670/1988, there is disclosed a forming method of patterned coating utilizing a magnetic force. According to this method, at first a liquid coating material containing powdery magnetic materials, such as nickel, stainless steel or iron, is applied to a natural surface or pre-coated surface of the object.

Then, while the coating material keeps its fluidity, a magnet -1 a- IfI is brought near. Thus, the powdery magnetic materials, which are uniformly dispersed within the liquid coating material, moves along magnetic force lines within the coating film, thereby prodiacing a configuration pattern different from adjacent areas.

In Japanese Patent Public Disclosure No. 10376/1982, there i~s disclosed a manufacturing method of metallic plate having a patterned coating. According to this method, at first a liquid paint containing an iron oxide is coated upon a metallic plate. Then, a magnetic pole is brought near the coated film, so that a pattern corresponding to the magnetic pole appears upon the film. And then, a baking treatment is applied to the coated film to finish the coated layer.

However, it has been found that an ordinary magnetic piece having a dimension of several inches or centimeters cannot produce a desirable explicit configuration pattern.

This kind of magnetic piece has special properties that in the vicinity of both ends magnetic forces are relatively strong but at the intermediate portion magnetic forces are poor. As a result, the configuration made by an ordinaryJ ma,!ne tic piece is liable to becomte a non-readable vague pattern.

SUMMARY OF THE INVENTION It is an object of the present invention to overcome the above drawbacks of the conventional forming method and to provide an explicit pattern within a coating film object utilizing a magnetic force.

Another object of the present invention is to provids -2a forming method capable of illustrating miscellaneous patterns without being restricted by the shape of the magnet itself.

According to the first aspect of the invention, there is provided a method of forming a visible patterned coating upon a surface of a substrate, comprising the steps of; preparing a plurality of separate magnetic elements closely arranged side by side in an arrayed module of the elements with the poles of each magnet disposed in a common plane parallel to the substrace with each pole of each magnetic element being closely disposed to an opposite pole of an adjacent magnetic element, bringing said module in close vicinity to a reverse side of a substrate, applying a layer of a magnetic paint containing a powdery magnetic material upon the surface of said substrate opposite the reverse side of the substrate to make a wet film thereon, whereby, due to the magnetic field of txe module, the visible patterned coating is formed in the layer of the magnetic paint due to movement of the powdery magnetic material in response to the magnetic force lines of separated magnetic elements in the module, which visible patterned coating differs in tone from adjacent areas in the layer of magnetic paint, and hardening the wet film through a baking or drying, thereby providing a cont:Lnuous visible o" pattern corresponding to the configuration pattern of said module upon the surface of the substrate, with said continuous visible pattern differing from the pattern 00 provided by each magnetic element by itself.

In this method, at first an imaginary chain of magnetic force lines are formed along the module of the elements, and 30 then a substrate is inserted into the magnetic field and Sexposed to the magnetic power. When magnetic paint containing oar' powdery ragnetic material is sprayed to the surface of the substra'ce, magnetic fine particles instantly begin to move within the wet film coward the direction of the magnetic force lines. As the wet film loses its fluidity, the movements of the magnetic material slow down and terminate near the magnetic force lines. Thus, an explicit continuous S-3- The claims defining the invention are as follows:- 1. A method of forming a visible patterned coating unon a Riirfaa nn f flhj2-at rrqmn44in 1cr 4 4- *ww f pattern corresponding to the configuration pattern of the module appears in a hardened film. The appearance of the pattern is not always identical with the configuration pattern of the magnetic chain, since magnetic force lines 3 5 vary depending upon the directions of the magnetic elements, especially upon the positions of North magnetic poles and South magnetic poles carried on the elements. It should be appreciated that a delicate pattern can be illustrated in the hardened film by changing the direction of each magnetic element.

Referring to the magnetic elements, which may be carried on a plastic sheet or metallic plate, a metallic magnet, ferrite magnet, sintered magnet or flexible magnet may be used depending upon the shape or magnetic properties.

Preferably, these magnetic elements are formed through a moulding process into a relatively small piece having a rectangular, triangular, polygonal or circular configuration.

By a combination of several configurations, any pattern can be illustrated.

According to the second aspect of the invention, t is provided a method of forming a visible patterned co..

upon a surface of a substrate, comprising the steps of; o preparing a plurality of separate magnetic elements closely arranged side by side in an arrayed module of the elements with the poles of each magnet disposed in a common plane 0° parallel to the substrate with each pole of each magnetic element being closely disposed to an opposite pole of an oO adjacent magnetic element, applying a layer of a magnetic paint containing a powdery magnetic material upon a surface of a substrate to make a wet film thereon, bringing said u" r module toward the surface or reverse side of said coated substrate in close vicinity of said wet film while the wet film retains its fluidity, whereby, due to the magnetic field of the module, the visible patterned coating is formed in the 0.35"" layer of the magnetic paint due to movement of the powdery O 0 magnetic material in response to the magnetic force lines of separated magnetic elements in the module, which visible -4- -4-

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i 3 t ,nJ applying a layer of a magnetic paint containing a powdery magnetic material upon a surfaco of a substrate to

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patternea coating differs in tone from adjacent areas in the layer of magnetic paint, and hardening the wet film through a baking or drying, thereby providing a continuous visible pattern corresponding to the configuration pattern of said module within the magnetic paint film, with said continuous visible pattern differing from the pattern provided by each magnetic element by itself.

In this method, a module of magnetic elements and a magnetic paint coated substrate are prepared separately, and JO then, the magnetic paint coated substrate is introduced into a magnetic field produced by the module while the o 0 0 *000 o 9 *e 00 0 00 *0 000 on 0 o 0 000 0 ,n 0 V 0 00 o 4 o 0 o 0 0000 0 00 0 00 00 00 00 0 O 0 00 0~ 0 0 -4amm

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A method of forming a patterned coating as claimed in c,,aim I, wheri, in said magnetic elements comprise bar-shape n TT .a L I we* film of magnetic paint keeps its fluidity., As the cop.Led substrate is inserted into the magnetic field and exposed to4 *the magnetic power, magnetic fine pard-*cles instantly begins to mlove within the wet film~toward the direction of the magnetic force lines. As the wet film loses its fluidity, the movements of the magnetiL, material slow down and finally terminate near the magnetic force lines. Thus, an explicit continuous pattern corresponding to the configuration pattern of the module appears in the magnetic paint film.

These characteristics of the invention are effected oby the module of the magnetic elements, which are closely disposed in order to maintain magnetic forces therebetween.

In a preferable embodiment of the invention, each magnetic element comprises a rectangula': or circular metallic plate having a North magnetic pole and a South magnetic pole situated at the opposite edges thereof, and adjacent magnetic elements are disposed such that the North magnetic pole of one element is positioned in close vicinity of the South maiinetic pole of the other element.

2C, In a further prc'ferable embodiment of the invention, the magnetic elements comprise-bar-shape or U-shape maqnet: each 1kving a North magnetic pole and a South magnetic pole I situated at the opposite edges thereof, and each magnet is perpendi~cularly disposed to the substrate.

In a further preferable embodiment of the invention,.

the magnetic elements are filled up within a rubber or plastic sheet in a pluraltty of striped patterns.

As an example of the magnetic powder to be contained in the magnetic paint, stainless steel powder, ferrous powder, Fe 3 O0 4 coated mica Powder, alloy powder containing iron, cobalt and nickel, magnetic iron oxide coated resin particles or the like may be utilized as far as it can move within the wet film or change its direction under the influence of a magnetic force. of course, it should be contained and dispersed uniformely in magnetic paint. The aforementioned Fe 3

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4 coated mica powder is well known as a nacreous pigment of paint. It should be noted that an ordinary pigment can be utilized in the present invention as far as it has a property to be influenced by a magnetic force.

As an example of the magnetic paint to be applied to the surface of the substrate, any kind of ordinary paint can be utilized as far as it can form a cured film after having 0 C finished a series of processes including a coating unaebr a fluid condition and baking or drying to harden the film. The magnetic paint includes, other than the magnetic powder, a pigment, vehicle resin, curing agent, 5olvent or the like.

The containing ratio of the magnetic powder relative to the magnetic paint is determined in a range such that an explicit pattern apoears under the influence of a magnetic force.

According to an experiment, the ratio is preferably more than 0.1 percent of the magnetic paint by weight.

The magnetic paint may be selected frion' an ordinary type which is hardened by a baking process or air drying process under the ambient temperature.

The coating system can be ,selected from the following: 1-coat finishing system in which magnetic paint is coated upon a substrate thereby making a single coating layer.

2-coat 1-bake finishing system in which at first miagnetic paint is coated upon a substrate, and then clear paint is applied on it by wet on wet process, and finally both layers 57816/90 are cured by a baking.

In an extended practical mode, this invention can apply to miscellaneous coating processes including more complicated coating steps, as far as the wet film is maoneti cally accessible from outside. For example, after a Vase color coating is formed upon a surface of a substrate as a first-coated layer, magnetic paint can be applied to the surface as an additional ornamental layer. When magnetic elements are brought near the ornamental layer, some portions of the ornamental layer becomes thinner under the influence of a magnetic force. As a result, some portions of the U rst-coated 0 0 o layer appears and provides delicate color patterns which have 0 not yet been illustrated.

It is also possible to apply clear paint over the completed magnetic powder layer in order to protect the patterned surface f rom an attack.

As an example of the substrate, non-.magnetizable 00(0material such as synthetic resin, rubber, ceramic or aluminum plate is preferable, since these materials do not affec-t the 020 magnrLic force of the magnetic element. of course, under the restricted condition such that the substrate is relatively 00 0 Especially, in the case that the magnetic elements are broug~ht near toward the surface of the substrate, the influence i.s small. However, such approaching operation toward the surface is not desirable because a collision may happen between the wet film and the magnetl.o elements, resulting in a destruction of the coated layer.

During the process of the present invention, the module of the magnetic eiements should be supported on a guiding -7- -LI _l.ii .tl l 1. 1 device, which may comprise a supporting rail, handling arm or similar member. When the magnetic elements are joined tujether by a plastic tape, attention should be paid to the temperature during a baking process.

The forming method of the invention can be preferably utilised for illustrating various letters, characters, or figures upon a coated surface. In addition, the method can be utilised for representing a repetitive pattern over a large area of the substrate. In this case, a plurality of magnetic modules are prepared or a single module is repeatedly used.

The invention will now be further explained with reference to the accompanying drawings, in which like reference numerals refer to like elements in the several views.

BRIEF DESCRIPTION OF ThE DRAWINGS FIG. 1 is a plan view of a reverse side of a substrate to be coated utilising the method of the present invention.

FIG. 2 is a sectional view taken along the line A A in FIG. 1.

FIG. 3 is a plan view of the surface of the substrate which is coated by the method of the present invention.

FIG, 4 is a sectional view of an alt.rnative embodiment oa similar to FIG. 2.

FIG. 5 is a plan view illustrating an alternative module 0 of multi-pole type magnetic elements.

S FIG. 6 is a perspective view of a modified module utilising column-type magnetic elements.

FIG. 7 is a plan view illustrating an arrangement J N r *9N of circular magnetic elements.

FIG. 8 is a plan view illustrating an alternative arrangement of the magnetic elements in FIG. 7.

FIG. 9 is a perspective view of a modified arrangement utilizing a combination of several types of magnetic elements.

FIG. 10 is a perspective view of a modified arrangement utilizing a combination of bar-shape and U-shape magnetic elements.

FIG. 11 is a plan view illustrating characters represented by the method of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 to 3, there is shown a first embodiment utilizing the method of the present invention. As shown in FIG. 1, to the reverse side of the substrate 10 to be coated, is sticked an arrayed module 15 which comprises a plurality uf rectangular magnetic elements 11 supported on a sticking tape 30. Each of the magnetic elements 11 carries a North magnetic pole and a South magnetic pole at the opposite edges. The magnetic elements 11 are disposed side by side, and adjacent elements 11 are disposed such that the North pole of one element is positioned in close vicinity of the South pole of the other element, and that the South pole of the one element is positioned in close vicinity of the North pole of the other element. Accordingly, strong magnetic force lines are produced between the elements, of course in an imaginary form.

FIG. 2 shows a relationship among the coated paint the substrate 10, the magnetic element 11 and the sticking -9- ~I I~

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tape 30. It should be noted that the element 11 is firmly sticked to the substrate 10 by the sticking tape FIG. 3 shows a surface which has been coated with magnetic paint. In this embodiment, after the module 15 of magnetic elements is sticked to the reverse side of the substrate 10, magnetic paint is sprayed on the surface. Since an imaginary chain of magnetic force lines is formed aloi g the module 15, as soon as the magnetic paint is thrown into I the magnetic field and applied to the surface of the substrate, magnetic fine particles instantly begin to move within a wet filn, of the magnetic paint toward the direction of the magnetic force lines. As the wet film loses its fluidity, the movements of the magnetic material slow down and finally terminate near the magnetic force lines, Thus, a transitional area 24 in which a color tone is different from that of the adjacent areFa appears on the surface of the substrate 10. The configuration of the area 24 is corresponing to the configuration pattern of the module 15. It should be noted that the configuretion of the pattern 24 is not identical with the configuration pettern of the separated magonetic elements 11.

Subsequently to the pattern making process, the surface ft 4t of the substrate 10 is subjected to a baking process or f 0 drying process for stabilizing bhe pattern. After the stabilization, the transitional area 24 grows an explicit pattern.

This pattern is essentially an transitional tone area among the coated layer, so that the surface of the substrate remains flat free from irregularities. This pattern does not vanish ap long as the coated laye'r rema-ihs on the surface.

Further, this pattern does not vary under the influence of a sunlight.

FIG. 4 shows an alternative embodiment of the pattern making process. At first, an appropriate pre-treatment is applied to the surface of the substrate 40, and then a primer layer 41 is formed by spraying of liquid paint to the surface.

From this stage, this invention is applied to the pre-coated surface. In the same way as the aforementioned process referring to FIGS. 1 Lo 3, the module of metallic elements 11 is sticked to the reverse side of the substrate 40 accompanied by a sticking tape 30. Subsequently to the primer layer 41, a magnetic paint layer 42 is formed. While,magnetic paint is sprayed upon the primer layer 41 to make a wet film thereon, the aforementioned pattern is formed within the magnetic paint layer 42. Further, subsequently to the magnetic paint layer 42, a final coating layer 43 of clear paint is formed. After the module of the magnetic elements is removed therefrom, these layers 42 and 43 are subjected to a baking or drying step.

In this embodiment, it is preferable to use strong magnetic elements having strong magnetic forces, since the primer layer 41 is intervening between the substrate and the magnetic ?0 paint layer.

FIG. 5 shows an alternative module 55 consisting of right and left multi-pole typr: magnetic elements 51, 52 and so on. Adjacent mn _uetic elements 51 and 52 are disposed Ssuch that each of the North magnetic poles of the element 51 is positioned in close vicinity of the South magnetic pole of the element 52, and that each of the South magnetic poles of the element 51 is positioned in close vicinity of the North magnetic pole of tho element 52. According to this arrangement, the magnetic force lines M ai, directed along the longitudinal direction of the module 55, so that a pattern revealed on the -11- 3 C 3333 surface of the substrate becomes a contiwious I-shape pattern having a relatively large width.

FIG. 6 shows a modified module 63 utilizing column-type magnetic elements 61, 62 and so on. This module 63 is used to illustrate a C-shape pattern on the surface of the substrate Adjacent magnetic elements 61 and 62 are disposed such that the North magnetic pole of one element is positioned in close vicinity of the South magnetic pole of the other element. According to this arrangement, the magnetic force lines are directed along the centerline of the module 63, so that a pattern revealed on the surface of the substrate becomes a continuous C-shape pattern. It should be noted that the revealed pattern is not a dotted pattern of the columntype magnets.

FIG. 7 shows a modified arrangemrent of magnetic elements. The module 66 comprises a plurality of circular magnetic elements 64, 65 and s~o on. As compared with the arrangement in FIG. 6, each of the magnetic elements is rotated in a right angle. Adjacent magnetic elements 64 and 110 65 are disposed such that the North magnetic pole of one element is positioned in the same lateral side as the South 00magnetic pole of the other element, so that two parallel S magnetic force lines M are f~ormed on the upper space of the module 66. According to this arr,-,zqement, the magnetic force lines are directed along the lateral sides of the module 66, so that a pattern revealed on the surface of the substrate becomes an arcuate pattern, which is not identical with the dotted pattern of the circular magnets.

FIG. 8 shows an alternative arrangement of the magnetic elements in FIG. 7. In this arrangement, adjacent magnetic o 00 3 33 elements 67 and 68 of the module 69 are disposed such that the North magnetic pole of one element is positioned in the same lateral side as the North magnetic pole of the other element, and that the South magnetic pole of one element is positioned in the same lateral side as the South magnetic pole of the other element. According to this arrangement, the magnetic force lines M are directed in a cross-over form due to a repelling force between the same magnetic poles, resulting in random lines. However, due to this random magnetic force lines, a delicate complicated pattern similar to an arcuate form appears on the surface of the substrate. Of course, this pattern is int identical with the dotted pattern of the circular magnets.

o o FIG. 9 shows a modified arrangement utilizing a combio 15 nation module 75 including two types of magnetic elements.

One type consists of ordinary two-pole magnetic elements 61 and 62, and the other type consists of multi-pole magnetic elements 71 and 72. As a result of the combination, the module can reveal a continuous H-shape pattern upon the surface of the substrate.

FIG. 10 shows a modified arrangement utilizing a combination module 85 including U-shape magnets 81, 82 and bar- S shape magnets 83, 84. In these kinds of magnets or magnetic elements, the North magnetic pole and the South magnetic pole are positioned at their distal ends. As shown in FIG. each magnet is perpendicularly disposed to the substrate The upper ends of the magnets are arranged in a grid form, so that the combination module 85 reveals a grid form pattern upon the surface of the substrate FIG. 11 shows sample characters represented by the -13j ii method of the invention. In this embodiment, magnetic elements are filled up within a rubber or plastic sheet in a plurality of striped patterns.

In an application of the method of the invention, a North magnetic pole and a South magnetic pole are easily detected by approaching a compass to the object. Therefore, the miscellaneous arrangements as shown in the drawings are easily prepared and utilized. The magnetic elements can be connected by a sticking tape or similar parts. Since the module of the magnetic elements can be removed easily, after the usage, no damage is occurred upon the substrate,, a l i

Claims

2. A method of forming a visible patterned coating upon a surface of a substrate, comprising the steps of: amil preparing a plurality of separate magnetic elements closely arranged side by side in an arrayed module of the elements with the poles of each magnet disposed in a common plane parallel to the substrate with each pole of each magnetic element being closely disposed to an opposite pole of an adjacent magnetic element, I c i,. applying a layer of a magnetic paint containing a powdery magnetic material upon a surface of a substrate to make a wet film thereon, bringing said module toward the surface or reverse side of said coated substrate in close vicinity of said wet film while the wet film retains its fluidity, whereby, due to the magnetic field of the module, the visible patterned coating is formed in the layer of the magnetic paint due to movement of the powdery magnetic material in response to the magnetic force lines of separated magnetic elements in the module, which visible patterned coating differs in tone from adjacent areas in the layer of magnetic paint, and hardening the wet film through a baking or drying, thereby providing a continuous visible pattern corresponding to the configuration pattern of said module within the magnetic paint film, with said continuous visible pattern differing from the pattern provided by each magnetic element by itself.
3. A method of forming a patterned coating as claimed in claim 1, wherein said magnetic elements comprise rectangular or circular metallic plates each having a North magnetic pole and a South magnetic pole situated at the opp(site edges thereof, and adjacent magnetic elements are disposed such that the North magnetic pole of one element is positioned in close vicinity of the South magnetic pole of the other element.
4. A method of forming a patterned coating as claimed. in claim 2, wherein said magnetic elements comprise J J rectangular or circular metallic plates each having a North magnetic pole and a South magnetic pole situated at the opposite edges thereof, and adjacent magnetic elements are disposed such that the North magnetic pole of one element is positioned in close vicinity of the South magnetic pole of the other element. -16- A method of forming a patterned coating as claimed in caim 1, wherein said magnetic elements comprise bar-shape or U-shape magnets each having a North magnetic pole and a South magnetic pole situated at the opposite ends thereof, and each magnet is perpendicularly disposed to the substrate.
6. A method of forming a patterned coating as claimed in claim 2, wherein said magnetic elements comprise bar-shape or U-shape magnets each having a North magnetic pole and a South magnetic pole situated at the opposite ends thereof, and each magnet is oriented perpendicularly to the substrate.
7. A method of forming a patterned coating as claimed in claim 1, wherein said magnetic elements are embedded within a rubber or plastic sheet so as to form a plurality of mutually parallel stripes.
8. A method of forming a patterned coating as claimed in claim 2, wherein said magnetic elements are embedded within a rubber or plastic sheet so as to form a plurality of mutually parallel stripes. Dated this 23rd day of September 1992 NIPPON PAINT CO, LTD By its Patent Attorneys R K MADDE.N ASSOCIATES -17-