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`Samsung Electronics Co., Ltd. v. Demaray LLC
`Samsung Electronic's Exhibit 1061
`Exhibit 1061, Page 1
`
`

`

`
`US. Patent—oct. 2, 1990 Sheet1 of4 4,960,651
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`Fig. 7.
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`Ex. 1061, Page 2
`
`Ex. 1061, Page 2
`
`

`

`US. Patent
`
`
`
`
`oct. 2, 1990
`
`
`
`
`Sheet 2 of4
`
`
`4,960,651
`
`
`
`
`Fig. 2.
`
`Ex. 1061, Page 3
`
`Ex. 1061, Page 3
`
`

`

`
`US. Patent—Oct. 2, 1990 Sheet 3 of 4 4,960,651
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`Fig 3.
`
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`FLOW CHART FOR ONE METHOD
`
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`OF THIN FILM TAG PRODUCTION
`
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`METAL AND METALOIO
`
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`INDUCTION MELT
`
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`PULVERISE INGOT
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`MIX POWDER
`
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`ENCAPSULATE
`
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`
`MACHINE SPUTTER
`
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`TARGETS
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`
`POLYMER Pa8
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`AISI 301
`
`STAINLESS
`
`
`
`STEEL BULK
`
`
`COATED FILM
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`
`ROLL FOIL
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`
`[LAMINATEJ+]S/AINLESS
`
`
`PAPER
`STAINTESS
`LAMINATE
`
`
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`
`STAMP. OUT
`BELS
`LA
`
`
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`ROLL AND PACK
`
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`
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`FOR DISPENSING
`
`GUN
`
`Ex. 1061, Page 4
`
`Ex. 1061, Page 4
`
`

`

`4,960,651
`US. Patent
`oct. 2, 1990
`Sheet 40f4
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`
`Fig.4(a)
`Fig.Ic)
` Fig.4(b)
`
`
`c= pen
`
`yi
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`Li
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`Ex..1061, Page 5
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`Ex. 1061, Page 5
`
`

`

`1
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`MAGNETIC DEVICES
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`4,960,651
`
`5
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`The invention relates to the magnetic devices, and in
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`particular to thin film amorphous magnetic materials, to
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`antipilferage tags or markers utilising such thin film
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`materials, and to the production of such materials and
`articles.
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`Antipilferage tags or markers are applied to articles
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`of commercein order to protect them from theft at the
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`point of sale premises. Typically, the tag is a magnetic
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`medium which is deactivated when a shop assistant
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`carries out the routine procedureat the timeofeffecting
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`a sale. Deactivation is usually effected by applying a
`15
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`magnetic field to the tag which itself includes a deacti-
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`vation layer, generally in the form of a magnetically
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`semi-hard material with a high coercive force, located
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`close to the active element in the tag. The semi-hard
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`deactivating layer can be magnetised by a strong mag-
`20
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`netic field and as-a result the magnetised deactivating
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`layer prevents the magnetically soft active layer from
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`responding when subjected to an alternating magnetic
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`field. Such deactivation. prevents detection of the mag-
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`netic tag when it (andthearticle to-whichit is attached)
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`pass through a detection system, typically in the form of 25
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`a walk-through framework which emits an alternating
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`magnetic interrogation field. This field is designed to
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`interact with a tag which has not not been subjected to
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`the routine deactivation procedure and to respond by,
`30
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`for example, trigerring a warning signal in the event
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`that detection of a non-deactivated tag occurs.
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`Typically, antipilferage tags are elongate strips of a
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`magnetically soft material, forming an active compo-
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`nent, which maybe carried by a suitable substrate. Such
`35
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`magnetic tags need to have carefully optimised mag-
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`netic properties. The magnetic material for such tags
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`should possess a high intrinsic permeability. It is desir-
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`able that the material additionally have low or zero
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`magnetostriction and low coercivity. A high permeabil-
`40
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`ity is usually, but not necessarily, associated with a low
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`coercivity. The tags must be easy to apply to an article
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`of merchandise, easy to produce and capable of produc-
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`ing a response in the intended detection system regard-
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`less of the orientation of the tag with respect to the
`45
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`detection system itself. Ideally, the magnetic material
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`from which the deactivation layer is formed should
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`have a square hysteresis loop and display high relative
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`permeability. Not all of these criteria are satisfied by
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`currently available tags.
`50
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`Currently, antipilferage tags are produced in amor-
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`phous form by melt-spinning. This technique produces
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`ribbons with practical minimum thickness of about 25
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`microns, An example of such a tag is described in US
`RE No. 32427.
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`With the known,thick markers additional elements of 55
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`shape or material are often used, attached to the main
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`magnetically nonlinear marker, to act as flux concentra-
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`tors (to increase the sensitivity of the marker to the
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`interrogation field). In particular, a flux concentratoris
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`often placed at the end of a long bar-type marker.
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`Current systems exploit the nonlinear magnetic prop-
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`erties of various types of generally magnetically soft
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`ferromagnetic materials in a time-varying interrogating
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`magnetic field. Frequency or waveform components in
`65
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`the magnetic response of the material which are not
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`contained in the interrogating field waveform are de-
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`tected to identify the presence of a magnetic marker in
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`the interrogation zone.
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`2
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`The shape of the material making up theactive ele-
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`ment of the magnetic marker stronger affects the mag-
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`netization response to an external magnetic field, be-
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`cause of the demagnetization factor N, which is depen-
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`dent on the shape. Known markers take the form of
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`amorphous metal
`ribbon ferromagnets which are
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`formed by melt-spinning or similar techniques. These
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`films are relatively thick, generally over 10 microns and
`often about 25 microns in thickness.
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`The demagnetizing field AH is equal to the product of
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`the demagnetization factor N and the intensity of mag-
`netization M.
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`The effective permeablity (12) of the tag can be de-
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`rived approximately by the following formula:
`1— +N
`ut
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`Me
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`where p; is the intrinsic permeability of the magnetic
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`coating, and N is the demagnetisation factor; this (N)
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`can be calculated as ‘a function of the shape of the arti-
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`cle. The inverse of the demagnetisation factor can be
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`termed the shape factor (1/N).
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`The effective permeablity of the active componentof
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`a tag thus dependsnot only on theintrinsic permeability
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`of the material of which it is formed, but also on its
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`shape. The lower the demagnetisation factor, the closer
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`is the effective permeability to the intrinsic permeabil-
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`ity. Low demagnetisation factors are also desirable
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`since they permit a lower intensity interrogationfield to
`be used.
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`to achieve low demagnetization
`_ Known markers,
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`factors, have to be quite long (usually a few cm.). We
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`have discovered that very low demagnetization factors
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`(preferably as small as the inverse of the relative perme-
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`ability 4; of the material) can be achieved byutilising
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`thin films to form the markers, andlead to the following
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`advantages:
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`(a) lower interrogation field (H) required for mag-
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`netic saturation—hencegreater sensitivity; and
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`(b) improved nonlinear behaviour, because of the
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`advantageous effect on the response curve (M-H
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`curve) of decreasing the demagnetization factor N.
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`According to one aspect of the invention there is
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`provided an article comprising a substrate and a thin
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`coated of a magnetic material, characterized in that:
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`(a) said substrate is a flexible, laminar material; (b)
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`said magnetic material is an amorphous metal glass of
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`high intrinsic magnetic permeability, with low or sub-
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`stantially zero. magnetostriction, and with low coerciv-
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`ity; and (c) said thin coating of a magnetic material is
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`not greater than 6 micronsin thickness.
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`According to a second aspectof the invention thereis
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`provided an antipilferage tag or marker comprising a
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`substrate and a. thin coating of a magnetic material,
`characterised in that:
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`(a) said substrate is a flexible, laminar material; (b)
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`said magnetic material is an amorphous metal glass of
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`high intrinsic magnetic permeability and with low or
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`substantially zero magnetostriction; and (c) said thin
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`coating of a magnetic material is not greater than 6
`microns in thickness.
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`Preferably, said thin coating is from 1 to 5 micronsin
`thickness.
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`With such a thin coating, the possibility of producing
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`tags of more convenient shapes is achieved. In particu-
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`lar, a tag having the dimensions and shape of a normal
`
`Ex. 1061, Page 6
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`Ex. 1061, Page 6
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`

`

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`3
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`price label can beutilised. This has the advantage that
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`known application techniques can be used to apply the
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`tags without the need for special equipment.
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`In one embodiment,the substrateis a flexible, laminar
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`material having a primary axis defining the major di-
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`mension of the substrate and a real or notional second-
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`ary axis perpendicular to said primary axis and located
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`so as to pass through the mid pointofsaid primary axis,
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`the ratio between the dimensions of said substrate mea-
`10
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`sured along said primary axis and said secondary axis
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`being not greater than 3:1.
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`Thin film markers are more mechanically flexible and
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`hence more robust than the known thick ones, and they
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`do not suffer appreciably from inefficiency introduced
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`by the electromagnetic skin effect (which can affect
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`thick markers at high frequencies).
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`Preferably, the thin coating is substantially cotermi-
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`nous with the substrate. In one form, it covers substan-
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`tially all of the substrate. This can be achieved by de-
`20
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`positing the material by physical vapour deposition
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`techniques, described hereinafter. In another form, the
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`thin coating is formed to be self supporting, e.g. by
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`rolling. The thin coating in both forms is preferably
`uniform in thickness.
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`25
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`The coating maytake the form ofa lattice the parts of
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`which are substantially uniform in thickness.
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`Generally, the thin coating will be bonded directly
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`to, or deposited on, the substrate; in some embodiments,
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`however, there is an intermediate layer between the
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`thin coating and the substrate.
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`A particular problem with known tagsis that they are
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`orientation-sensitive—that is, their output in detection
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`gates is dependent on the orientation of the tag. The
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`35
`shapes of the tags according to preferred embodiments
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`of the invention ameliorate this problem. The problem
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`is further reduced according to a further preferred fea-
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`ture of the invention whereby the thin coating has mag-
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`netic properties which are isotropic in the plane of the
`substrate.
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`Thin film markers in general need not be as long as
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`currently available strip markers, making them less
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`conspicuous and cheaper than the known markers. This
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`leads to a further advantage that the length/width ratio
`45
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`can be: made as low as 1 (this is desirable so as to in-
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`crease the volume of the material and hence the re-
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`ceived signal). In particular, square or circular markers
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`(or ones of similarly squat aspect) have the advantage,
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`hitherto unrecognised, that they are very sensitive in
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`virtually any orientation—in fact maximally sensitive
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`(or very nearly so) in any orientation in an interrogating
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`field lying in two or more mutually orthogonal direc-
`tions.
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`In one embodimentof the present invention, the thin
`55
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`film is configured as a broken or discontinuous flat loop
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`of ferromagnetic material. Such a configuration func-
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`tions both as a marker an to concentrate the flux,
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`thereby to increase the sensitivity of the marker to the
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`interrogation field. Preferably the marker is a circular
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`annulus of nonlinear ferromagnetic material. This gives
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`the advantage of orientation versatility, since the flux
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`concentration will be achieved for any component of
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`applied field lying in the plane of the loop. The breaks
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`or discontinuities in the loop are necessary to ensure the
`65
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`generation of free magnetic dipoles which, whenthe tag
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`or markeris in use, can radiate the detected signal. Such
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`a marker can be formed by the methods disclosed
`herein.
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`50
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`60
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`4,960,651
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`4
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`It has been found by the present inventors that mag-
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`netic isotropy in the plane of the substrate is desirable
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`and can be much improved by controlling conditions
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`governing physical vapour deposition techniques such
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`that the atomic growth structure is almost entirely per-
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`pendicular to the substrate surface.
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`The deposition technique can be sputtering, e.g. pla-
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`nar magnetron sputtering, electron beam or thermal
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`evaporation (enabling a faster deposition rate but
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`achieving a less dense product) or electrolysis. Another
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`technique is organometallic vapour pyrolysis. Further
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`possibilities include: laser driven physcial vapour depo-
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`sition in which a laser beam is scanned over a target
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`surface to ablate the material to be deposited; and depo-
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`sition from a liquid using a chemical technique.
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`In planar magnetron sputtering, a magnetron gener- |
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`ates an annular ring of flux so that sputtering is carried
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`out in a magnetic field where lines of force are perpen-
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`dicular to the substrate, which is carried by a rotating
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`drum. Ferromagnetic atoms in the sputtered composi-
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`tion tend to “line up” along these lines of force hence
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`giving rise to some order on an atomic scale. The effect
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`of this order on the isotropic behaviour of the material
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`depends on the position of the drum carrying the sub-
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`strate, since this affects the angle between the magnetic
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`lines of force and the substrate. We have found that the
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`application of a strong magnetic field to oppose the
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`obtaining magnetic field may beneficially affect the
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`isotropy of the finished product. Also, replacement of
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`the drum bya flat substrate (to reduce the angle effect
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`discussed above) may be beneficial. A further arrange-
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`ment is to screen part of the drum from the magnetic
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`field in an attempt to avoid build up of the ferromag-
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`netic atoms causing anisotropic behaviour over the
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`whole surface of the drum.In this way the effect of any
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`build up can be reduced.
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`Improvementsin isotropy can also be achievedif the
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`magnetic material is deposited onto a suitable synthetic
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`polymeric substrate, e.g. a polyester, polyamide or po-
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`lymide. It is important that the substrate surface is clean
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`and smooth, this serving to reduce both oxidation con-
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`tamination and opportunities for domain wall pinning.
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`Metal foil e.g. aluminium foil may be used, either as
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`substrate or as an intermediate layer, but usually is less
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`satisfactory because of inadequate surface smoothness.
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`If the substrate is a plastics polymer coated with a layer
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`of aluminium,this assists in conducting heat away from
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`the substrate during deposition. One particularly suit-
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`able polymer for use as the substrate is a cast polyimide,
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`‘Upilex’, from ICI.
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`The magnetic qualities of the amorphous magnetic
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`film may in certain cases be enhanced by an annealing
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`cycle after deposition of the thin film—this being re-
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`ferred to in general as ‘post annealing’. The deposition
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`process conditions determine the amount of unwanted
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`impurities, the crystallographic pinning centres, and the
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`surface roughnessof the film; post annealing generally
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`improvesall of these parameters and gives a more ho-
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`mogeneous product with increased intrinsic permeabil-
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`ity and improved isotropy. For example, the thin film
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`may be deposited onto ‘Upilex’, which has the advan-
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`tage of being heat resistant allowing several hours post
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`annealing of the film at 250° C. to improve the qualities
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`described above and thus to maximise the signal output
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`if desired. The conditions under which post annealingis
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`used will be adapted in any particular case to take ac-
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`count of the properties of the substrate.
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`Ex. 1061, Page 7
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`Ex. 1061, Page 7
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`

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`4,960,651
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`5
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`Theideal thickness for a sputtered film is probably 1
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`micron; below 500 nm, surface pinning effects become
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`dominant and the signal obtained from the tag in an
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`interrogation gate is poor. For a label with dimensions
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`of about 3 cm by 2 cm,a thickness of 3 microns is theo-
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`retically better, but may be too expensive to achieve
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`economically by sputtering. Thicknesses greater than 3
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`microns are not preferred, since bulk effects predomi-
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`nate and the demagnetisation factor becomes too great.
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`As mentioned above, improved signal and isotropy
`
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`can be achieved by annealing the film. Such annealing,
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`however, must take place below thecrystallisation tem-
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`perature of the magnetic film—typically this is around
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`500° C. Polyesters such as ‘Melinex’ tend to be difficult
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`to anneal because of low. heat resistance; polyamides
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`and polyimides such as ‘Upilex’ or ‘Kapton’ are better in
`
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`this regard, but more expensive.
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`A further technique which may be beneficial is the
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`injection of a plasma during sputtering. This in effect
`20
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`gives deposition and annealing simultaneously. Energy
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`is injected by the plasma into-the growing magnetic
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`film, which results in atomic annealing.
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`The magnetic material deposited may be a mixture of
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`metals with a suitable glass-forming element or ele-
`25
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`ments. Compositions typical of those currently used to
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`form melt-spun magnetic metallic glasses are suitable.
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`One such composition is Co-Nb, with a suitable glass
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`forming element. Other suitable amorphos alloys in-
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`clude the transition metal/metalloid (T-M) and transi-
`30:
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`tion metal/transition metal (T-T) alloys. Typical metal-
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`loids in this context are boron, carbon,silicon, phospho-
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`rus and germanium, which may form about 15-30% of
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`the alloy. T-T alloys contain late transition metals such
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`as Fe, Co, Ni or early transition metals such as Zr and
`35
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`Hf and have good thermal stability. The composition of
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`T-M type alloys amenable to solification to an amor-
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`phous phase is typically around Tgo9 M20, e.g. Feso Bzo.
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`By adding Co and Ni to Fe-B systems, an increase in
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`Curie temperature results, with an increase in saturation
`40
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`magnetic induction. The addition of other metalloids
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`also has an effect on material properties such as satura-
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`tion magnetic induction, Curie temperature, anisotropy,
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`magnetisation and coercivity. The most appropriate
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`alloy for any particular application can be selected
`45
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`through considertion of the desired properties.
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`The amorphous ferromagnetic alloy used as the ac-
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`tive layer (i.e. the thin coating over the substrate) pref-
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`erably possesses a coercivity (H,) that approacheszero,
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`an intrinsic permeability of greater than 104, minimal
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`magnetostriction and low magnetic crystalline anisot-
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`ropy (K). These properties are determined by both the
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`composition of the alloy and the deposition technique
`and conditions.
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`The preferred alloys are combinations of elements,
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`generally of metal and metalloid elements, which, when
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`combined. in the correct atomic percentages, give an
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`amorphousstructure under the right deposition condi-
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`tions. Many such alloys contain Co, Fe, Si and B. Ni
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`maybe also be present. Suitable alloys are amorphous.
`60
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`metal glasses, for example: Cog Fey Nie Mog Sie Bs
`
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`wherea is in the range of 35 to 70 atomic percent, b zero
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`to 8 atomic percent, c zero to 40 atomic percent, d zero
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`to four atomic percent, e zero to thirty atomic percent
`
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`and f zero to thirty atomic percent, with at least one of
`65
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`groups b, c, d ande, f being non zero. The inclusion of
`
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`nickel is found to assist in increasing the ductability of
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`the product, which facilitates its handling and usage.
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`Suitable properties may also be achieved with alloys of
`
`350
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`6
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`iron, aluminium and silicon that are designed to have
`
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`zero: magnetostriction. Magnetic properties of some
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`
`alloys are very senitive to a changein their stoichimet-
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`ric composition. Others are magnetostrictive and hence
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`do not possess a sufficiently high permeability. The
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`ratio Co:Fe markedly affects the magnetostrictive prop-
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`erties of the alloy; the atomic ratio Co:Fe is preferably
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`in the range 8:1 to 20:1, more preferably about 16:1. A
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`preferred range of composition (in atomic percent) is:
`
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`
`Co, 35-70; Fe, 2-7; Ni 10-35; Mo, 0-2; Si, 12-20; and B,
`6-12.
`
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`Onesatisfactory alloy is CogsFe4Mo2Sii6B12, cur-
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`
`rently manufactured as Vitrovac 6025. Another is Vi-
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`trovac 6030 which contains manganese in place of mo-
`
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`lybdenum. A further and presently preferred alloy. has
`
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`the composition Co,42; Fe, 4; Ni, 28; Si, 16; B, 9 atomic
`
`percent.
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`
`Whenusing a substrate with a low softening or melt-
`
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`ing point, it may be advantageous for the substrate to be
`
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`cooled during deposition to maintain a sufficient quench
`
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`
`rate for the formation of the amorphousstate, and to
`
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`reduce thermal stresses in the substrate or film which
`
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`can affect magnetic properties. Preferably, the tempera-
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`ture of the substrate during deposition is kept low—ad-
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`vantageously below 60° C., and betterstill below 20° C.
`
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`
`and where practical (by suitable cooling techniques) at
`or below 0° C.
`:
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`The substrate can be a continuous. web or sheet of
`
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`suitable material. This may be a polymer,e.g. a polyes-
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`ter, for example polyethylene terephthalate, a polyam-
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`ide, or a polyimide, which leadsto a flexible sheet prod-
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`uct which can easily be stored and cut for subsequent
`use.
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`An antipilferage tag or marker of this invention will
`
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`generally include a deactivation layer or zone(s) adja-
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`cent to or overlying said thin coating. This may take the
`
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`form of a continuous layer of of a multiplicity of. dis-
`crete elements.
`
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`
`The. present invention also relates to deactivation
`
`
`
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`
`
`techniques, Currently, security tags are deactivated by
`
`
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`
`
`
`several different methods, the most commonof which is
`
`
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`
`
`to apply a fixed magnetic field to a semi-hard magnet
`
`
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`
`
`portion of the tag to saturate the soft magnetic material
`
`
`
`
`
`
`
`
`of the tag and hence renderit inoperative or to change
`
`
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`
`
`
`the effective magnetic properties so that it is not recog-
`
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`
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`nised by the detection system. The semi-hard magnet
`
`
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`
`
`
`portion is conventionally formed by one or more areas
`
`
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`
`
`of semi-hard magnetic material secured to or integral
`
`
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`
`
`
`
`
`with the tag. The material used as the deactivation
`
`
`
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`
`
`
`material should not be a truly hard magnetic material,
`
`
`
`
`
`
`
`since the high coercivity of such materials would re-
`
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`
`
`
`quire the use of a high deactivation field, hp, which
`
`
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`
`
`
`could lead to interference with other, non-related mag-
`
`
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`
`
`netic media such as credit cards or pre-recorded audio
`
`tapes.
`
`
`
`
`
`Deactivation techniques should be such as to secure
`
`
`
`
`
`
`complete deactivation of the active component of a tag
`
`
`
`
`
`
`
`
`whena fixed magnetic field is applied, and should occur
`
`
`
`
`
`
`
`almost regardless ofthe relative orientation between the
`
`
`
`
`
`tag and thefixedfield.
`
`
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`
`
`The deactivating material may be fabricated by thin
`
`
`
`
`
`
`
`film processes (for example those referred to above for
`
`
`
`
`
`
`
`the thin film tags) or by spreading of a magnetic slurry
`
`
`
`
`
`
`
`onto a suitable substrate. The deactivating material may
`also be formed from a sheet of solid material reduced to
`
`
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`
`
`
`
`
`
`
`
`
`an appropriate thickness by a process such as rolling,
`
`
`
`
`
`
`casting or extrusion. Such a sheet may be between 1
`
`Ex. 1061, Page 8
`
`Ex. 1061, Page 8
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`

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`4,960,651
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`20
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`7
`
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`micron and 50 microns thickness, but is preferably in the
`
`
`range of 5 to 35 microns.
`
`
`
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`The deactivator may be in the form of a continuous
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`sheet placed close to the active element. The deactiva-
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`tion process can, however, be made moreefficientif the
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`deactivator film or sheet is not continuous, but broken
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`into a multiplicity of discrete elements. Examples of
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`suitable configurations are rectangular, circular or po-
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`lygonal pieces offilm or sheet 1 mm to 10 mm across,
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`laid or fabricated in a pattern close to the active ele-
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`ment; or a numberof longstraight strips laid in a grid or
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`matrix of crossed grids, or a numberof serpentinestrips.
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`The magnetic field patterns of these configurations are
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`more effective in their deactivation function than a
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`continuous film or sheet of deactivator of equivalent
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`volume since the magnetic field which these non-con-
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`tinuous configurations producein the active film lies in
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`a numberofdirections, thus rendering it less prone to
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`cancellation by a uniform external field.
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`Preferably the deactivation field should be high in
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`comparison with the interrogation field used at the
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`detection system. The deactivation field, Hp, is prefera-
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`bly 2000 A/m or greater; however, so as to avoid un-
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`wanted interference with other magnetic media, the
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`value of Hp should not exceed 10,000 A/m. This com-
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`pares with the interrogation field which may be, for
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`example, an alternating field of about 500 A/m. If a
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`deactivated tag is taken through the interrogation gate
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`close to the sides where the interrogation field is highest
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`then the tag may be re-activated to a greater or lesser
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`extent. This may, in some systems, generate a signal in
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`the detection system which is a false positive. Different
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`commercial systems use different interrogation field
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`parameters and different detection techniques; for ex-
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`ample, the alternating frequency may be a single com-
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`ponentfield or a multi-componentfield. The maximum
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`frequency of the interrogation field is usually not more
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`than a few tens of kHz, and is more often around 3-10
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`kHz. In one multi-component system, three frequencies
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`of around 5 kHz, 3.3 kHz and 20 Hzare used. With this
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`particular system,if the value of Hp were significantly
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`less than say 1000 A/m, and if the deactivated tag is
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`taken through the interrogation gate close to the sides
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`wherethe interrogation field is high, then although the
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`tag may be re-activated to a greater orlesser extent, this
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`will nevertheless produce a signal from the gate which
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`can still be differential from that of a fully active tag:
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`instead of giving an outputsignal when the 20 Hz inter-
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`rogation field passes through zero, the signal will occur
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`at transects through a positive field value. The genera-
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`tion of such a spurious signal need not be of undue
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`concern with this particular system since a detection
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`system can be designed to discriminate between signals
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`which have a different time separation, as will be the
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`case with a true response and a “false” response. Other,
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`simpler systems, however, are unable to differentiate
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