FR2574099A1 - IMPRESSION-WRITING SUPPORT INFALSIFIABLE - Google Patents

Abstract

1. Printing-writing support having a character of immediate fixation of the inks of ball-point pens called erasable by rubbing out or scratching, characterized in that it comprises a substrate associated, at least on the surface, with inorganic or organic products having an absorbent porter equivalent to an oil absorption at least equal to 150 g per hundred grams of these products, oil absorption measured in accordance with the method NFT 30022 (or ISO 787/5/1980).

Description

The present invention relates to the problem posed by the risk of

  falsification attached to the use of a pen to

  ink ball erasable by scrubbing or scraping.

  We know that ballpoint pen inks are mainly

  They are composed of mineral pigments with remarkable properties of stability and unobtrusiveness. However, these inks have the disadvantage of not being easily amenable to corrections, unless aggressive technical means that leave

  subsist a trace or indelible mark on the written medium.

  In order to remedy this drawback, a ballpoint pen ink has been proposed, for example of the type described in US Pat. No. 4,097,290. According to this teaching, the ink can be considered as including, in its composition , a first

  fast solvent used to immediately hook pigments

  colored elements on the support so as to establish a

  on the support. The ink also contains a second solvent which can be described as slow and whose evaporation leads to the intimate bonding between the binders of the colored pigments and the surface layer of the support. As long as the second solvent is not completely evaporated, the colored pigments can be erased

  by friction, such as scraping or, more particularly, scrubbing.

  Thus, the use of a stylobead loaded with an ink of the above type allows successive corrections during a given period of time and facilitates, for example, the execution of documents.

  or printed characters of a current nature.

  It is conceivable, however, that the use of such a

  lobble to fill in security documents, documents of

  their fiduciary or scriptural character makes it possible to falsify such documents throughout the duration of fixation

  color pigments, which is essentially

  because of the conditions of use, the nature of the

  port, ambient temperature, hygrometric degree, etc.

  Such a risk is all the more important since it is

  impossible to check, in each case that may be present, the nature of the ballpoint pen used to fill a document

safety.

  Faced with such a risk, it was therefore necessary to

  propose for the execution of such valuable documents, sup-

  prohibiting any possibility of falsification of marks printed or written by means of ballpoint pens

  type described in US Pat. No. 4,097,290 or of a type

  sin, but leading to the same result.

  The German application published before examination 29 51 486 pro-

  in this sense, the incorporation into the constitutive mass of the printing-writing medium, microencapsulated dyes and an acid-accepting acid dye silicate. Under the pressure generated

  by the tip of a pen used to write on such a tablet.

  The capsules are punctured and release the dye which reacts with the acidic silicate to form a trace in the mass of the support. Thus, any attempt to falsify, to eliminate

  the trace of the pen's own ink, reveals the mar-

  than internal to the paper that represents, then, the material trace

  an attempt to falsify. If such an attempt is

  by means of an eraser strongly supported on the support, the

  locally exerted pressure develops, over the entire surface con-

  surrounded, a mark further increasing the proof of attempted forgery. Such paper is, in fact, not practically suitable for the purpose sought, since any manipulation, pressure or shock borne by the paper during use, handling or storage, leads to the formation of marks which can be

  crippling for later use.

  In addition, such a paper can not be used in the case of bound and superposed print-writing media because the pressure exerted on the paper from above is transmitted to at least one of the underlying copies on which the

  same traces as the marks on the first paper.

  In addition, the manufacture of such a support is relative-

  expensive, because of the need to carry out the micro-encapsulation

  dying of the dye and to implement particularly delicate manufacturing means to prevent the incorporation into the mass does not reveal indelible marks prohibitive on

  the support definitely realized.

  European Patent Application 0 029 714 proposes to involve, by coating on a printing-writing medium, a film of adsorbent products, electron acceptors, such as a

  silica gel or a reactive kaolin.

  It may be thought that it is therefore necessary, for an attempt to falsify, to use an ink having an affinity with the adsorbent product, so as to provide

  electrons capable of reacting with such a product. Such a demand

  The deposit can not be charged to all the inks used, so that the guarantee of non-forgery can not be obtained. One can also think that an adsorption bond

  in the physical sense of the term, and that in certain circumstances

  consistency, a scrub can, possibly, be carried out.

  Such a proposal therefore does not respond positively

to the problem.

  French patent application 80-11 124 (2 483 480)

  a security paper comprising on the surface microcapsules

  sules containing an ink solvent of the type of that taught by US Patent 4,097,290. The microcapsules, punctured during the application of pressure by the tip of the pen, release the solvent they contain, which dilutes, at least in part,

  the ink of the pen and entrains the inorganic pigments in the neck.

superficial.

  Any attempt to falsify

  colored trace of such paper can only be carried out

  treating the superficial layer in which the diluted pigments have been entrained. Such physical destruction of the medium can not

  be concealed and thus provides evidence of an attempt to falsely

fication.

  Such a proposal may be considered as

  both a theoretical solution to the real problem posed.

  However, in practice, a paper or printing medium

  writing, performed using this technique, is relatively expensive

  high, taking into account the need for micro-encapsulation

  of the solvent responsible for the subsequent dilution of the ink.

  In addition, it must be considered that any pressure applied

  printing, writing, handling, storage, manufacturing, etc., also leads to the rupture of the microcapsules which release the solvent in the absence of ink,

  since in these pre-use phases such documents

  have not been impressed or written.

  Thus, during writing or subsequent printing, it may occur that the colored mark is affixed to an area or surface whose microcapsules have already been punctured. In such a case, the function of these microcapsules can no longer intervene,

  since the solvent is already diluted or evaporated.

  An attempt to falsify on these areas or surfaces

  could then be carried out.

  The French patent 81-18 794 (2 491 968) proposes a

  security paper associated in bulk or on the surface with micro-

  capsules containing a solvent for solubilizing the dye having

served at registration.

  In addition to the same disadvantages as those to be

  French account 80-11 824 (2 483 480), it should be noted that such a proposal does not appear to be compatible with

  inks containing mineral pigments.

  The present invention aims to provide a solution to the problem thus posed by the existence of inks and stylobeads of the type described in US Pat. No. 4,097,290, by proposing a

  eliminates any possibility of exfoliating the ink immediately.

after deposit.

  Another object of the invention is to propose a new

  support that can be produced at a very attractive price and does not

  no risk of partial deterioration of its function during the manufacturing, handling, storage, trimming,

bundling, etc ...

  Another object of the invention is to provide a

  print-write medium that can be made of super-sized bundles

  posed, without the risk of successive reproductions on the lower or underlying supports of information printed or written on

the first accessible medium.

  It is still an object of the invention to propose a new support that makes it possible to combine the effects of the object of the invention with other known treatments in order to confer characteristics

  additional infalsifiability, such as the appearance of

  by means of solvents or chemical reagents

or erasers of the trade.

  To achieve the above aims, the object of the invention

  The invention is characterized in that it comprises a substrate associated, at least on the surface, with inorganic or organic products having an absorbency equivalent to an oil uptake of at least g per cent of product, oil measured according to

  the method NF T 30 022 (or ISO 787/5/1980).

  Various other features emerge from the

detailed description which follows.

  The object of the invention is based on the use of the remarkable absorbing properties of certain mineral or organic products and, more particularly, those characterized by an absorbency equivalent to an oil uptake at least equal to

  g per cent of product, measured oil

  read according to the method NF T 30 022 (or ISO0 787/5/1980).

  The surface porosity, quite particular and remarkable particles of these absorbent products, leads, when a support includes such products surfaced, coated or introduced into the mass, at least partial and instantaneous absorption of all or part of the dyes. This absorption is

  significantly higher than the normal absorption of an im-

  pressure-writing surfaced or coated by the usual products used in the composition of such supports, such as cellulose,

  glue, filler, starch, latex, kaolin, calcium carbonate, etc ...

  Advantageously, according to the invention, the products absorb

  bants are also selected from those characterized by a surface

  very high specificity greater than 20 m2 / g, measured according to the

  BET thode (BRUNAUER, EMMETT and TELLER, J. AM CHEM SOC 60, 309

(1938)).

  Absorbent products, meeting these two characteristics,

  The compositions can be used by being incorporated into the mass or coating by coating the surface of the support. In this respect, all

  the supports usually usable in print-writing can

  associated with the absorbent product according to the invention, that is,

  say plastic films and fiber webs of origin-

  more or less cellulosic, obtained by paper or by

any other process.

  A support according to the invention has an inert nature and insensitive to external agents, as well as thermal or climatic changes. In addition, such a support is insensitive

  the pressure constraints that can be applied during the

  processing, storage, handling, trimming,

  cleaning, etc ... during which he undergoes no destruction

of capacities that it conceals.

  Another advantage of the invention lies in the fact that such a support can be treated by incorporation, in the mass or on the surface, at a low cost, since the treatment of such a support can be carried out by the usual techniques

  manufacturing and / or surfacing-coating.

  Preferably, according to the invention, it is used, as

  products with remarkable absorption characteristics.

  precipitated silicas, for example those designated "FK 320 DS" sold by the company Degussa or those designated "Tixosil 375, Tixosil 333" sold by the company Rhône-Poulenc, aluminum silicates, for example, those sold under the name of "Pasilex" by the company DEGUSSA, - sodium silico-aluminates, for example those sold by the company RHONE POULENC under the name "Zeolex", - organic pigments of ureaformaldehyde, for example those

  sold under the name "Pergopak M 2" by CIBA-GEIGY.

  These products can be introduced into the mass during the preparation of the material constituting the plastic film or pulp, as is usually practiced in this field as regards the mineral fillers introduced into the dough. Lap] oportion can then be understood

  between 5 and 20% by weight remaining in the support. These products can

  It may also be deposited by surfacing or coating on one of the faces of a substrate, such as a plastic film or a sheet of paper, at a rate of 1 to 10 g / m 2. This deposit may occur during the manufacture of the substrate or by a clean operation,

  outside the manufacture, by the means usually used to

  surfacing or coating a substrate.

  In the case of surface deposition, the product or products with high absorption power enter, for the essential part, into

  the composition of the coating, being associated with the usual binders

  such as starches, starches and their derivatives or other

  binders used and known in the art to carry out the

  chage or surfacing. In this sense, it may also be envisaged to associate with absorbent products one or more additional charges usually used, for example in paper mills, to improve the deposition conditions, the cohesion, the smoothness, the

color, etc ...

  It must be considered that the two above methods can also be implemented simultaneously, for example, by providing, during manufacture, a substrate associated with absorbent products incorporated in bulk and deposited

on one of the faces.

  The absorption conferred by the products according to the invention

8: - -

  makes it impossible, except in the case of a deep alteration of the support, which makes obvious an attempt at falsification, a scrubbing of the ink-deposit on such a support. So, even in the presence of a

  ink comprising a premie-solvent, said-simple snap, and -

  A slow second solvent whose subsequent evaporation then allows:

  only to obtain an intimate bond, the products according to the invention-

  to oppose any scrub instantly after marking-

of such a support. - -: -

  . Some examples of implementation of the subject of the invention for a substrate constituted by a paper are given below.

  and intended to represent an improperly written impression-writing medium

  corn. t -, - f: W u X d- - 0f =? -: f Example 1: In-line processing ::

: = - ::

  It incorporates in the pulp, before its-passage on machine, a

  mineral product with high absorbency, such as aluminum silicate

  precipitated minium, for example that denominated in the trade: "Pasilex" marketed by DEGUSSA Company, at a rate of 15 Z: remaining in the paper after manufacture. The "Pasilex" product is: -selected in the range having an absorbency equivalent to an oil uptake of 160 g per 100 g of product and offering a specific surface area of 100 m 2 / g calculated according to the BET method ( Brunauer,

  EMMETT and TELLER, J. AM. CHEM. SOC., 60, 309 (1938)). -

Example 2 Surface Treatment:

  =: == We produce a sauce of: surfacing with:

  a binder, such as oxidized starch or enzymic starch, on the basis of

  - 30 parts by weight, - - -

  a mineral product with high absorbency, such as silica "FK 320 DS" at the rate of eight parts by weight and having an absorbency equivalent to an oil uptake of 230 g / 10 10 g -2; and a surface area of 170 m 2 / g (BET);

  - - water at the rate of eighty-four parts by weight.

  r) (5) It is applied with an adhesive paper, on paper, on the surface of a 93 g / m2 paper sheet of paper. to deposit 2 to 5 g of dry matter of the sauce by

square meter.

  Example 3 Surface Treatment A surfacing sauce is produced comprising: a product with a high absorbency of mineral nature, such as "Tixosil 375" silica, at the rate of eight parts by weight and having an absorbency equivalent to an oil uptake of 310 g / 100 g and a specific surface area of 180 m 2 / g (BET), an additional charge consisting of a talc 005, marketed by TALC LUZENAC, at the rate of 8 parts by weight; a binder such as "Rhodoviol 30/5" marketed by the company RHONE-POULENC, at the rate of three parts by weight,

  - water at a rate of eighty one parts by weight.

  This sauce is applied in conventional coating, for example by means of a dragging coater, so as to deposit from I to

  5 g of dry matter per square meter of surface.

  Examples 2 and 3 above can be implemented

  for a substrate consisting, for example, of an opaque film of poly-

  oriented propylene, for example in the case of card application

credit cards, identity cards.

  The print-writing medium thus obtained has

  normal characteristics of printability and prohibits any attempt

  falsification by friction, in particular by exfoliation, of a

  mark made with a stylobille of the type of that of the

  or neighboring type, but leading to the same situation.

  sultat, and comprising an ink, said gummable for a time corresponding, for example, to the evaporation time of a

slow solvent.

  Such a print-writing medium may also include a tamper treatment from chemical compounds, such as coloring reactions with solvents, acids,

  bt) a: ,, oxidants, reducers, etc ...

  The object of the invention finds a particular application

  interesting in the field of security papers or valuable documents, such as checks, bills of exchange, as well as supporting or other means of personal identification, such as credit cards, cards

  toll subscription, identity cards, etc ...

  The invention is not limited to the examples described, since various modifications can be made without departing from its scope. he

Claims (7)

CLAIMS:   1 - Printing-writing medium having an immediate fixing character ballpoint pen inks erasable by scrubbing or scraping, characterized in that it comprises a substrate associated, at least on the surface, with mineral or organic products having an absorbency equivalent to an oil intake of at least 150 g per hundred grams of products, measured oil intake   according to the method NF T 30 022 (or ISO 787/5/1980).   2 - Support according to claim 1, characterized in that the substrate is associated with inorganic or organic products having in addition a specific surface area greater than 20 m / g, measured   according to the BET method (BRUNAUER, EMMETT and TELLER, J. AM, CHEM SOC. , 309 (1938)).   3 - Support according to claim 1 or 2, characterized   in that the products are incorporated in the mass of the substrate.   4 - Support according to claim 1 or 2, characterized   in that the products are provided by coating or surfacing.   - Support according to one of claims 1 to 4, characterized   characterized in that the substrate is made of paper.   6 - Support according to one of claims 1 to 5, characterized   characterized in that the substrate is a plastic film.   7 - Support according to claim 3, characterized in that the mineral or organic products are incorporated by reason of   15% by weight remaining in the mass of the support.   8 - Support according to claim 4, characterized in that the mineral or organic products are deposited on the support   at the rate of 1 to 5 g of dry matter per square meter of support.