Abstract: An identity card or credit card type of card is equipped with a validity-checking device that makes it possible to do away with the use of complementary, sophisticated checking equipment. It results from the association of a structure S.sub.1 comprising at least one layer of piezoelectric material and a structure S.sub.2 comprising a material capable of switching electrically between two optical states (I) and (II) that are different in terms of ocular perception. During the bending of the card, the validity or non-validity of the card can be attested to by the appearance or non-appearance of the validity of the card.

Abstract: Each copy of software is assigned a unique identifying code pattern which is printed on all documents produced with that software by a high resolution printer. The unique identifying code pattern is a plurality of spaced apart marks having a size no greater than about 300 dpi, and is therefore, at best, barely noticeable to the human observer. The "invisible signature" is also reproduced on documents made by unauthorized copies of software which can therefore be traced. Preferably, the unique identifying code is replicated multiple times over the document using an error correcting code to assure that at least one replication will be clear of matter selected for printing by the software. A high resolution scanner extracts and identifies the code patterns printed on the document.

Abstract: A novel carrier for carrying a group of items, such as cans, bottles or the like which hold beverages, foods or the like, is made of a substantially transparent, plastic material having micro-embossed partial cube-corner type retro-reflector elements on a surface of the carrier. Each item includes an individual machine readable bar code thereon which is at least partially covered by the reflector elements. The package has a machine readable bar code thereon which is not covered by the reflector elements on the carrier. The reflector elements prevent the individual bar codes on the items from being read by a typical bar code reader beam by reflecting the light emitted from the bar code reader so the light cannot penetrate the carrier and read the bar code underneath the reflector elements. The bar code on the package, which when scanned by the bar code reader beam will retrieve package information, can be read by the reader since it is not covered by the reflector elements.

Abstract: An apparently conventional document such as an identification (ID) card is constructed as a laminate within which is a code or other coding indicia such as a photograph, bar code or fingerprint. concealed from human view. The document is read by a conventional electro-optic reader means placed against a face of the card, if the reader uses a beam of light in the wavelength absorbed by the material with which the coded indicia is produced, but reflected by the background against which the coded indicia is "seen" by the beam. The card is preferably a laminate of at least an upper lamina and a lower lamina, each made of a synthetic resin which has a substantially white imprintable surface conventionally printed with the identification of the owner of the card with a pigment-free, non-aqueous ink which is visible to the human eye but substantially transparent to wavelengths outside the visible range.

Abstract: A retroreflective animal tag, such as an ear tag or the like, which has a reflective surface with wide angularity and high reflectivity.

Abstract: A phase hologram is embossed in a mylar web having a reflective layer which is made from tin tungsten oxide, zinc sulfide, or a mixture thereof. The embossed microtexture produces a hologram that is semi-transparent, thereby allowing the visualization of indicia underlying the hologram.

Abstract: A substantially transparent carrier for carrying a group of items, such as bottles which hold beverages, is made of a plastic material which includes a chemical blocking agent. The carrier includes a machine readable bar code thereon. Each item includes an individual machine readable bar code thereon which is at least partially covered by the carrier. The chemical blocking agent is capable of blocking, by reflection or absorption, light having a narrow wavelength "tuned" or selected to prevent the individual bar codes on the items from being read by a typical bar code reader beam while allowing the bar code on the carrier to be read.

Abstract: A visually verifiable and machine-readable security thread having at least two security detection means located thereon, where a first security detection means comprises a machine-readable repeating pattern and where a second security detection means comprises visually verifiable metal-formed indicia. Such security threads are suitable for use with security documents, such as banknotes and the like, labels and any other documents or means of identification used for purposes which make the verification of the authenticity of each specimen desirable at least once in its lifetime.

Abstract: A security document with a design (e.g. a generally oval seal) is constructed in such a way that the design is full value halftone, such as produced from juxtaposed line screens having a frequency between 100-133 lines per inch. Negative and positive masks having an image (e.g. arabic numeral, letter, or other symbol), are used with the screens to produce a printing plate. A document is printed with the printing plate in a conventional lithographic process, and there is an overprinting on the design (at least that portion having the image) with a white opaque ink or overprint varnish to produce an image. The image is not readily visible to the naked human eye when viewed generally perpendicular to the plane of the document, but is readily visible by the naked human eye when the document is tilted so that it is viewed distinctly non-perpendicular to the plane of the document.

Abstract: A security paper is provided for incorporation in a security document, or other document having intrinsic value. The security paper includes a resinous substrate sheet on which indicia are printed. Paper sheets are laminated on either side of the resinous substrate sheet using a suitable adhesive. In the laminated security paper, the indicia printed on the substrate sheet are undetectable when viewed in reflected light, but become apparent when viewed transmitted light within the visible spectrum. The security paper may be incorporated in a security document in which a set of indicia printed on at least one of the outer faces of the paper sheets, such that the indicia on the substrate and the indicia on the document form a total image when viewed in transmitted light. A method for manufacturing the security paper is also provided.

Abstract: An authenticatable item and security device carry a number of symbols (4A, 4B, 4C, 6A, 6B, 6C) identifiable to the naked eye, there being at least two sets of at least three symbols. All the symbols within a set are substantially identical, are positioned in a non-overlapping, regular geometric arrangement, and at least one common viewing angle of inclination, exhibit substantially the same optical performance, the optical performance varying with inclination viewing angle.

Abstract: Documents and data, patterns, etc., applied thereto, which are present in the form of a surface relief, in particular in the form of embossed characters, are provided partially in the area of this surface relief with luminescent substance which is testable visibly and by machine. The luminescent substance is introduced either into raised or into depressed areas of the surface relief, so that characteristic features of the surface relief are reflected in its spatial distribution. The data can thus be tested for falsification and at the same time for authenticity in a simple way.

Abstract: A composite microdot fabricated form a microdot and at least one composite layer. The composite layer is selected to impart to the composite microdot at least one of the characteristics of enhanced visibility, camouflage, buoyancy control, magnetic attraction, and controlled biodegradation. A second composite layer may also be applied to the microdot. A coating may also be selectively applied to the composite microdot, the coating having at least one of the features of being waterproof, water repellant, hydrophilic, soluble and opaque.

Abstract: A heat sensitive system comprises a document having a localized, non-pressure sensitive, coating of chromogenic composition activated at moderate temperatures. Quickly striking the chromogenic composition with a fingernail or blunt object produces a colored image by frictional heat. The chromogenic composition contains a chromogenic compound and a color developer which are non-pressure sensitive and non-reactive at room temperature. The chromogenic composition can be an intimate mixture of the chromogenic compound and the developer or alternatively separate layers of each of the components.

Abstract: A plastic card provided with a magnetic stripe, which is very difficult to forge or alter and, even tough subjected to forgery or alteration, enables the forgery or alteration to be easily detected in appearance.The plastic card comprises a card substrate and a hologram-magnetic stripe comprising, provided on said card substrate in the following order, an adhesive layer, a first magnetic recording layer, a second magnetic recording layer, a metallic reflecting layer and a hologram forming layer. The first magnetic recording layer and the second magnetic recording layer are such that one of the magnetic recording layers has a coercive force at least twice as high as the other magnetic layer and a Curie point at least 100.degree. C. below the other magnetic layer and, when the magnetic recording layers are heated at a temperature in the range of from the lower Curie point to 30.degree. C. below the lower Curie point, they become substantially identical to each other in saturation writing current value.

Abstract: Non-continuous reflective holograms or diffraction gratings are provided in various forms for authenticating documents and things, and for decorative and product packaging applications. In one specific authentication application, such a hologram or diffraction grating is firmly attached to a surface that contains visual information desired to be protected from alteration. Examples of such information include written personal data and photograph on a passport, driver's license, identity card and the like. The reflective discontinuous hologram is formed in a pattern that both permits viewing the protected information through it and the viewing of an authenticating image or other light pattern reconstructed from it in reflection. In another specific authentication application, a non-transparent structure of two side-by-side non-continuous holograms or diffraction patterns, each reconstructing a separate image or other light pattern, increases the difficulty of counterfeiting the structure.

Abstract: An optically variable device for use on security documents to deter unauthorized reproduction is provided which contains a warning message that is not readily apparent to an observer but that reproduces as a visible warning message when copied. The device comprises a pattern of light reflecting surfaces which comprise a reflection diffraction grating having a plurality of grooves that vary in orientation and blaze angle. In an alternative embodiment, a machine-readable optically variable device is provided in which the pattern of specularly light-reflecting surfaces produces a machine-readable message in response to light impinging on the device.

Abstract: Basic commodity or collector's object in particular of a high replacement collector's value with an identification label, whereby the identification label is formed in material of the object itself as an optical mark which is not visible if illuminated with a light source with a wavelength range within the sensitivity range of the human eye but is visible to the human eye if illuminated with a light source outside this sensitivity range the label being situated in an area of a housing surface or other area of the which is optically transparent for at least a part of the wavelength range within the sensitivity range of the human eye and for an additional wavelength range which is outside the sensitivity range of the human eye and which is used to read the label, whereby the undamaged nature of the area is at least to a high degree important when evaluating the replacement or collector's value.

Abstract: The present invention pertains to a method of producing an anti-counterfeiting document or currency which acts and feels like existing paper currencies. The method of the present invention laminates two sheets of currency paper on each side of a thin durable substrate film, thereby forming a durable document which maintains a paper-like feel. The currency of the present invention exhibits unique and powerful anti-counterfeiting features compared to those presently available. The currency of the instant invention also lasts significantly longer than conventional "paper" money.

Abstract: A security article such as a banknote, credit card, identity card or travel document includes a security element which is visually detectable in transmitted light to display portions which transmit light and portions which are opaque, the security element including a plurality of layers that include a light-transmitting support layer and two or more series of opaque regions. The arrangement of the opaque regions is such that at certain parts of the security element the regions overlap to prevent light transmission and elsewhere along its length the opaque regions do not overlap or only partially overlap such that light transmission through the security element occurs.

Abstract: The document or substrate containing the information to be protected is covered with a liquid crystal or other such material capable of being made transparent using a process such as heating it to a higher temperature than ambient room temperature. In this manner the information on the substrate is normally invisible and thus not accessible to individuals without special equipment. For copying, the coated substrate is then placed on a copier machine in which the transparent glass plate of the copier is heated, for instance by electrical resistance heating, to a temperature matching the temperature-transparency window of the coating on the document. The information on the substrate may also be made visible for viewing by covering the coating with a transparent plate heated to the proper temperature. A second coating of different color but substantially the same temperature transparency may be selectively applied to the first coating to provide normally visible information.

Abstract: An optical marking system in which objects are coated with materials for purposes of applying secretly coded marks on the objects. The coating materials are transparent in daylight and have the property of absorbing ultraviolet light. When such materials are applied to a portion of the surface of an object which is a good ultraviolet reflector, only the uncoated portion reflects ultraviolet. Thus, the marked object is therefore seen as having the coated portion blocked-out when viewed through a device which filters out all but ultraviolet wavelengths but appears to be unmarked when observed without the viewing device. Similar coding of objects may be achieved by appropriately selected paints, papers and other materials.

Abstract: A printing medium (10) receives and displays images produced by a thermal printer of a standard facsimile machine. The printing medium (10) comprises plain-surfaced printing paper (12) and a cover medium (14) disposed over the printing paper so as to pass through the facsimile machine in combination with the printing paper. The cover medium (14) includes a bottom surface facing toward the printing paper (12) and a top surface facing away from the printing paper. A coating of heat-transferable ink (16) is disposed on the bottom surface, the ink being transferred from the cover medium (14) to predetermined locations on the printing paper (12) as the printing medium passes through the facsimile machine.

Abstract: A data-written medium in which the data is readable with a light source having a main wavelength of 600 to 700 nm, the medium comprising a substrate and an ink layer containing not more than 0.1 g/m.sup.2 of a chromatic color dyestuff having absorption substantially at 600 to 700 nm and at least one other color dyestuff as the remainder. The ink layer is formed on the substrate so as to have a form constituting the data. Also provided is a data-written medium in which the data is readable with light sources having a main wavelength of 600 to 1,500 nm, the medium comprising a substrate, a first ink layer containing not more than 0.1 g/m.sup.2 of a chromatic color dyestuff having substantial absorption at 600 to 700 nm and another dyestuff as the remainder, and a second ink layer containing a substance having substantial absorption in a near infrared region. Each of the two ink layers is formed so as to individually have a form constituting to two corresponding data.

Abstract: A method for producing a validation mark on security paper includes printing the mark on the paper using an ink that has the same color as the paper but which has more uniform directional reflectance than the sheet of paper. That is, the dried ink is a more uniform diffuse reflector than is the paper. When the mark is illuminated by a light source located on one side of the mark, the mark appears lighter than the paper around it when viewed from the same side as the light source, but the mark appears darker than the paper around it when viewed from the side opposite the light source. An exemplary formulation is given.

Abstract: A diffraction grating of reflective or transmissive lines is formed by a regular matrix of pixels each containing a respective curvilinear portion of one or more of said lines. When the pixels are illuminated, each generates a two-dimensional optical catastrophe image diffraction pattern whereby the total image diffraction pattern of the grating is optically variable but structurally stable. The invention further provides a diffraction grating of reflective or transmissive lines, comprising a multiplicity of diffraction grating regions which are at least partly separated by multiplicity of grating free regions. Each grating free region has a dimension which is at least large enough to be resolved by the human eye, the total grating free areas not exceeding about 20 to 50% of the total area of the grating. The disclosed diffraction grating is useful as a security device for currency or credit cards.

Abstract: A placemat defining a translucent upper surface supporting a red/yellow obscuring design; a plate formed of a transparent red material; and a latent image formed on the placemat obscured by the red/yellow design, the plate being placed upon the placemat overlying the latent image to filter out the obscuring design and reveal the latent image.

Abstract: An optical identification label consisting of an area of hologram or diffraction grating which is transparent to visible light but reflects incident light with a specific reflective directivity. By identifying the reflectivity directivity, it is possible to identify the authenticity of the label and, hence, the object to which the identification label is affixed. The fact that the identification label is transparent to human eyes offers a strong discouraging effect on potential forgers. Further, the pattern of the reflected light may be used as means for encoding data.

Abstract: A method and system for securing a substrate such as paper and the like against counterfeiting, photocopying, and facsimile transmission and an applicator and paper for use in the method and system and with the applicator. The method and system comprises providing a substrate having a background color on one surface thereof, covering at least one selected area of the surface with one of the colorless color developer and a colorless color former dye, wherein the color developer and color former dye react when mixed to produce a first given color which is different form the background color and applying the other of the colorless color developer and the colorless color former dye to at least a portion of the at least one selected area to change the background color to said first given color.

Abstract: The invention is a document security system characterized by a data substrate having photographic or printed information on a base print, and also having a personalized polarization-altering overlay sealed to the base print and encoded with additional coded information readable under the influence of a polarizing viewer. The low-security information, such as name, social security, account number and photograph, are printed on a card to form the base print. Additional information of greater security, which may be a bar code or alphanumeric characters, is imprinted in the polarization-altering overlay by an appropriate physical process, such as radiation exposure or thermal, chemical or mechanical treatment, which optically modifies localized regions of the overlay.

Abstract: Transparent optically variable device comprising a symmetric three-layer coating. The three-layer coating has first and second partially transmitting absorber layers and a dielectric spacer layer disposed between the first and second absorber layers.

Abstract: Commercially available pigments mixed with fluorescence compound to obtain print stuff mixtures for transfer thereafter to mattes. The print stuff mixtures obtainable thereby are used to print securitY and face-value documents which will be color copier resistant, that is, not be accurately reproducible or replicable by a photocopier. An empirical test is provided which will allow the ordinary skilled printer to determine the best titer of commercially available fluorescence to be used in the ink/pigment mixing scheme.

Abstract: The present invention relates to a data carrier, in particular an identity card, paper of value or the like, having applied thereto a plane element (OVD) with optically variable effects which are dependent on the viewing angle. Within at least a predefined area of the OVD there is additional information provided between the OVD and the surface of the data carrier in the form of characters, patterns or the like which, subsequently incorporated into the OVD, overlays the optically variable effect of the OVD and is likewise visually recognizable. The invention also relates to a method for producing such a data carrier.

Abstract: Optical variable interference device with peak suppression having a reflector with first and second surfaces. A thin film multilayer interference stack is disposed on the first surface. The interference stack is comprised of at least two periods with each period being comprised of a metal absorber layer and a dielectric spacer layer.

Abstract: In a facsimile machine which receives transmit data based on an original that is transmitted from a facsimile transmit machine through a telephone line at its data scrambler and which records an image of the original that is transmitted by decoding the received transmit data on recording paper at its thermal transfer printer portion, in order to maintain the secrecy of the original until the recording paper is delivered to an intended receiver by making it impossible to read the recording paper itself on which the transmit data is recorded and outputted, an image by invisible ink is recorded on the recording paper. Also, the image by the invisible ink which is recorded on the recording paper is displayed by converting it to a visible image by means of a visual observation apparatus, so that only a predetermined person can read the recording paper.

Abstract: A substrate, such as a banknote or travellers' check, carries a security device including in association at least one embossed transitory image, such as a latent or transient image and an embossed linear area. The arrangement is such that when the embossed region of the substrate is viewed from different angles each image and linear area can be visually discerned.

Abstract: In a security document having an embedded security element in the form of a transparent thread with electrically conductive material in at least two layers, at least one layer is transparent or partly transparent at least in certain areas. The partly transparent layer interacts with marks located on the thread in such a way that the marks are largely concealed in incident light but are recognizable visually in transmitted light.

Abstract: A security paper includes at least two layers of paper each having inner and outer surfaces and predetermined mechanical properties, color and optical density. Authentication indicia is printed on the inner surface of at least one layer. The indicia is formed of a chemically, mechanically and thermally stable medium having a predetermined color, color intensity and optical density. A chemically, mechanically and thermally stable adhesive permanently adheres the inner surfaces of the layers together. The adhesive has a predetermined color and optical density. The color and optical density of the layers, the color, color intensity and optical density of the medium and the color and optical density of the adhesive combine to render the authentication indicia detectable in transmitted light and substantially imperceptible in reflected light.

Abstract: A method of security coding an article which comprises applying to the article an identification mark comprising at least one colorless or weakly-colored infra-red absorbing material and an article carrying one or more identification codes applied according to the method. The method is suitable for marking documents, currency and equivalents, such as cheques, credit cards and tickets, and for the identification of copyright materials and high valued added goods, such as tapes, cassettes, books, films, cameras, perfumes, spirits and designer goods to inhibit counterfeiting.

Abstract: Non-continuous reflective holograms or diffraction gratings are provided in various forms for authenticating documents and things, and for decorative and product packaging applications. In one specific authentication application, such a hologram or diffraction grating is firmly attached to a surface that contains visual information desired to be protected from alteration. Examples of such information include written personal data and photograph on a passport, driver's license, identity card and the like. The reflective discontinuous hologram is formed in a pattern that both permits viewing the protected information through it and the viewing of an authenticating image or other light pattern reconstructed from it in reflection. In another specific authentication application, a non-transparent structure of two side-by-side non-continuous holograms or diffraction patterns, each reconstructing a separate image or other light pattern, increases the difficulty of counterfeiting the structure.

Abstract: Non-continuous reflective hologram or diffraction grating devices are provided in various forms for authenticating documents and things, such as those that contain visual information desired to be protected from alteration. Examples of such information include written personal data and photograph on a passport, driver's license, identity card, transportation pass, and the like. The reflective discontinuous hologram or diffraction device is formed in a pattern that both permits viewing the protected information through it and the viewing of an authenticating image or other light pattern reconstructed from it in reflection. The same master hologram or diffraction grating is made into distinct authenticaton devices by forming replicas thereof that have different patterns of reflective material which form distinct indicia, such as a different alpha-numeric character.

Abstract: An optical recording medium of the present invention has on a substrate information recording patterns (2) and (3) distinguishable by a difference in light reflectivity, and is characterized in that said information recording pattern (2) is comprised of a portion (2a) of high reflectivity and a portion (2b) of low reflectivity and at least a part of said information recording patterns is formed by a diffraction grating or hologram (3). Since such plural types of information can be formed at the same time and at high density, the present invention has a merit of its having excellent fake-proofness and its manufacturing process being simplified.

Abstract: A credit document with improved protection against forgery comprises a film which is attached to a local portion of a surface of the credit document. The film includes at least one security mark. The security mark comprises a micro-relief structure for optically diffracting incident light. A protection profile in the form of a macro-relief structure is also embossed into the surface of the credit document. The security mark and the protection profile overlap in part. The relief lines of the protection profile macrostructure are bent away from the plane of the surface of the credit document sufficiently to provide visible gloss effects due to the reflection of incident light. When this arrangement is utilized one or more visible breaks in the security mark occur when the security mark is removed from the credit document. In addition, the security mark is so deformed by the protection profile, that the deformation is easily visible if the security mark is attached to a second (i.e. a forged) credit document.

Abstract: An interlaminar sandwich comprises first and second lacquer layers, a diffraction structure embedded between the first and second lacquer layers, a heat activated adhesive layer disposed one one of the lacquer layers, and a transparent stabilization layer disposed over the other lacquer layer, the stabilization layer distributing heat evenly through the interlaminar sandwich so that when heat is applied to the stabilization layer, the adhesive layer will bond the interlaminar sandwich to a substrate. Preferably, the interlaminar sandwich also contains an intermediary layer between the stabilization layer and the first lacquer layer which bonds these layers together. At temperatures below 170.degree. C., the adhesive layer is bonded so intimately to the substrate that the interlaminar sandwich cannot be removed from the substrate without tearing it. At temperatures above 150.degree. C., the lacquer layers soften, thus destroying the diffraction structure.

Abstract: An article of manufacture contains a substrate which supports a diffraction element divided into surface portions having optically-active microscopic relief structures. At least one pair of surface portions is mirror-symmetric with respect to the orientation of the corresponding relief structures. Each surface portion of the pair has an optically-active, microscopic, asymmetric relief structure defined by an orientation azimuth angle. The azimuth angles are 180.degree. apart. The mirror symmetric pairs constitute optical markings which are machine-readable. The readout device generates an incident light beam and contains photosensors and electronics to output the intensity difference between pairs of diffracted light beams. Alternatively, each surface portion of the diffraction element has a volume hologram rather than a microscopic relief structure for diffracting incident light.

Abstract: This invention is concerned with security paper for bank notes, cheques and like documents in a security strip of enhanced security which is more difficult to counterfeit than the present bank notes containing window threads.

Abstract: An antitheft security system is disclosed for automotive, marine, and other valuable personal articles such as objects of art and valuable collectible objects. A dealer/installer is provided with equipment comprising a main unit having a memory, a keyboard for data entry, and a visual screen for monitoring the data entry procedure and also for displaying to the dealer the precise locations on the article where it is to be marked. The unit randomly selects different marking locations on the article by calling up form its memory a programmed universe of several hundred possible marking sites for each particular type of item. An image of the item is displayed on the visual screen, which indicates the exact location where each marking is to be made. The security codes are applied by a portable hand-held marking head containing an electrostatic, noncontact ink jet spraying nozzle which invisibly microprints a unique, classified security code in a dot matrix format of alphanumeric characters onto the surface.

Abstract: The safety design printed on a currency paper is composed, on the one hand, of a basic design with parallel lines (10, 20, 30) extending in a specific direction, with a plurality of interruptions, by means of which regions in the form of letters are marked out, and of a plurality of line segments (1, 11, 21) which fill these regions. A plurality of groups (R to Z) of letters located next to one another respectively form a word. Within each group, all the line segments are parallel to one another, but from word to word the directions of the respective line segments differ from one another, so that there is a plurality of words with line segments inclined differently in relation to the direction of the basic-design lines. Mutually adjacent successive lines of the basic design and mutually adjacent successive line segments have alternately different colors, preferably three different colors being represented.

Abstract: A computerized technique for generating masters for embossing and printing color images with local regions of variation of an optical characteristic such as reflectance is disclosed. The color image is read into a computer and displayed on the computer screen. An electronic embossing mask is created for each local region which is to have a preselected optical variation. The line pattern is designated for each local region mask and an embossing film is exposed with each electronic embossing mask for creating in the embossing film a composite image including each line pattern in each local region. A plurality of electronic color separation masks are generated from the original color image, and each of these is combined with an electronic embossing mask to form an electronic line color separation mask having line patterns which correspond to those designated for the local regions.

Abstract: A transparent overlay that can protect a document from tampering has a transparent cover sheet, a layer of hot-melt adhesive over one surface of the transparent cover sheet, and a polymeric image-receiving layer over the exposed face of said hot-melt adhesive layer. The transparent cover sheet can be a simple thermoplastic film but preferably is retroreflective sheeting which can bear a pattern or legend that is noticeable only when viewed retroreflectively. When the polymeric image-receiving layer is dye-receptive, it can be imaged by using a thermal printing head with a dye-donor element. A preferred polymeric image-receiving layer that is dye-receptive is chlorinated poly(vinylchloride).