FR2730188A1 - WRITING OR COLORING ARTICLE WITH INK MADE FROM A COMPACT BLOCK OF POROUS MATERIAL - Google Patents

Abstract

The writing or coloring article comprises a compact block (2) made of a porous material with open pores which also acts as a reservoir for the ink, which is wrapped in a covering envelope (3) impermeable to ink, except for the area corresponding to the writing tip (5). Preferably, the porous compact block is obtained by thermofusion of thermoplastic microbeads.

Description

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  INK WRITING OR COLORING ARTICLE

  MADE FROM A COMPACT BLOCK IN

POROUS MATERIAL

  The present invention relates to a writing or coloring article comprising a body giving said article its rigidity, a reservoir for the ink and a writing tip which is supplied with ink from the reservoir. In this type of article, the ink can either be trapped in a fibrous reservoir or in the liquid state.

  in a hollowed-out part of the body constituting the reservoir.

  In all writing or coloring articles known to the applicant, the various elements useful for the writing or coloring function, namely the ink either in the liquid state or in a fibrous reservoir, the writing tip and possibly a buffer tank, all these elements are contained in a rigid body which gives said article its rigidity and its external presentation. This rigid body is generally a metallic cylindrical body or a molded plastic body. This body is necessarily composed of a main part inside which the various aforementioned elements are introduced and a closing part. Said closure piece can be either opposite the point

  of writing is possibly around the writing tip itself.

  Thus in a conventional manner, a writing or coloring article of this type is composed of at least four distinct parts: the two constituent parts of the rigid body, the writing tip in the simplified version where the ink being liquid it acts as both transfer tip and writing head, and the closing cap of the rigid body. When the ink is liquid, it is desirable to have a buffer reservoir intended to absorb and restore the excess ink from the writing tip by capillary action in the event of a variation in the pressure prevailing in the reservoir. ink. Such a buffer tank is known in particular from the document

EP-516 538 of the applicant.

  By cons such a buffer tank is not necessary when the ink is not in the liquid state, but trapped in a fibrous tank, that is to say a -2- set of fibers including polyester arranged around of the transfer point so that the ink gradually migrates, as it is consumed by the writing point, from the fibers of the fibrous reservoir to

the transfer tip.

  It should also be noted that it is on the outside of the rigid body that all the technical or commercial information is carried, which requires

  subsequent printing operations on the finished article.

  The goal that the applicant has set is to offer a writing article that is of a simpler structure and in particular whose body assures him the

  stiffness does not have to be in two separate pieces.

  This object is perfectly achieved by the writing or coloring article of the invention. It is an article which includes a body giving it its rigidity and containing a reservoir for the ink, as well as a writing tip supplied with

ink from said reservoir.

  Typically, the rigid body consists of a compact block of a porous material with open pores also acting as a reservoir for the ink. In addition, this compact block is wrapped in an ink-impermeable covering envelope, with the exception of the zone corresponding to the

writing tip.

  According to a particularly simplified variant embodiment, the writing tip is a portion of the compact, hydrophilic block, of great hardness, shaped as a writing tip. Thus in this particularly simple version, the writing or coloring article comprises only three parts: the compact block, the covering envelope and the cap. The covering envelope is generally a film, independent of the compact block. However in an even more simplified version, the covering envelope is constituted by the layer

  the outermost of the compact block, which is impermeable to ink.

  The compact block can consist only of a porous hydrophilic material with open pores. In this case said compact block forms the reservoir -3-

  main for ink, like conventional fiber reservoirs.

  The compact block can also have two adjacent zones, a first zone made of a porous hydrophilic material and a second zone made of a porous hydrophobic material forming a buffer tank, capable of absorbing and restoring any excess ink. In the present text, the concept of hydrophilicity and hydrophobia is a relative concept since it is linked to the nature of the ink, and in particular its viscosity and its surface tension. A porous material in which said ink naturally diffuses under normal conditions of use is considered to be hydrophilic with respect to a specific ink; is considered hydrophobic compared to the same ink a porous material

  wherein said ink does not diffuse under normal conditions of use.

  However, an excess of ink can diffuse into the hydrophobic material when the conditions of use are modified, in particular by abnormal increase in pressure. This latter version is particularly suitable in the case where the compact block has an interior recess forming a reservoir of liquid ink, said recess being connected to the writing tip by the hydrophilic material of the

  first zone and being formed in the hydrophobic material of the second zone.

  This version increases the capacity of the writing or coloring article in ink, because the ink is in the liquid state and no longer trapped in

the pores of the compact block.

  Preferably, the porous compact block is based on micro-beads, the grade, particle size of which is known, as well as the distribution, molecular weight and morphology. It is obtained by thermofusion sintering of micro-balls made of thermoplastic materials. Furthermore, the porous compact block obtained by sintering can thus be produced from several materials based on micro-balls, the grades, particle sizes of which are also known. that the distributions, the weights

molecular and morphologies.

  -4- Preferably, the porous compact block is produced from microbeads of the same hydrophobic thermoplastic material, the part of the compact block intended to constitute the first zone then undergoing a treatment capable of rendering it hydrophilic. It can in particular be oxidative plasma treatment or

  optionally treatment with a surfactant.

  As regards the covering envelope, it may be an adjusted sheath, obtained using a shrink film. In this case, it is the compact block which gives the writing or coloring article its final shape. The sheath

  covering, retracted around said block, precisely adopts the shape thereof.

  The covering envelope can also consist of at least one

  semi-rigid strip arranged around the compact block and heat-sealed or glued.

  In this case, the final form of the writing or coloring article according to the invention is that adopted by the semi-rigid strip. It may be the same strip folded back on itself and the inner edges of which are heat-sealed or glued. It can also be two strips arranged on either side of the compact block and which are heat sealed or bonded together along their common area. Preferably, such a semi-rigid strip, constituting the covering envelope, is made of a complex (rigid or semi-rigid) multilayer material comprising for example on its inner face a heat-sealable film, on its outer face a film having good decorability and an intermediate film impermeable to liquids and gases, forming a barrier against

ink evaporation.

  In all cases, whether it is a simple retractable sheath or one or more complex semi-rigid or rigid multilayer strips, the information or the decoration affixed on the outside of the article is obtained by direct printing on the film of overlap, which allows for

  much more reliable and less costly multi-color printing.

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  The present invention will be better understood on reading the description

  which will be made of two exemplary embodiments of an ink writing or coloring article, produced from a compact block of porous material, illustrated by the appended drawing in which: FIG. 1 is a representation schematic in longitudinal section of an article in its most simplified version in which the compact block acts as the main reservoir, FIG. 2 is a schematic representation in section of an article in which the compact block has an internal recess, 3 and 5 are schematic plan representations of an article whose covering envelope is based on complex or mono-material strips folded back on itself,

  And Figure 4 is a sectional view of the article of Figure 3 along the axis IV-IV.

  The writing or coloring article of the present invention is characterized by the presence of a porous compact block, with open pores, which has a double function, the first being to give the article its rigidity and the second being to constitute a reservoir for the ink, either main reservoir like a conventional fibrous reservoir or buffer reservoir capable of absorbing and restoring the excess ink

  if the pressure in the liquid ink tank changes.

  In a first exemplary embodiment illustrated in FIG. 1, article 1 is composed only of three elements, namely the compact block 2, the sheath 3

  covering the compact block 2 and the cap 4.

  The compact block 2 has for example a cylindrical shape terminated by a conical end 2a. The extreme zone corresponding to point 5 of this

  end 2a serves as the writing tip for article 1.

  The outer sheath 3 completely covers the compact block 2 except for the writing tip 5. This sheath is produced from a heat-shrinkable film, inside which the compact block is placed, before

  heat shrinkage treatment.

  6 - The compact block 2 is made of a porous material with open pores, hydrophilic. It constitutes the main reservoir for article 1, after the liquid ink has been injected inside said block 2. This injection is carried out in particular using an injection needle penetrating an orifice 6 formed in the median axis of the lower end 2b of said compact block 2. The point 5, serving as a writing point, of the compact block 2, is itself hydrophilic, but has a hardness, possibly greater than the rest of the compact block 2, which allows it to resist friction against the

writing medium.

  Thus in this particularly simple version of an article 1 of the invention, the compact block 2 simultaneously acts as an ink tank, transfer point and writing point; moreover, being rigid, it is it which gives Article I its final external shape and its rigidity. In the mold intended for sintering, the material reserved for the tip function is stacked followed by the material intended for the reservoir function and the assembly is sintered in a single operation by

  heat treatment and / or microwave.

  The sheath 3 has three functions. According to the first function, it makes article 1 impermeable to liquids and gases and forms a barrier against the evaporation of the ink and prevents the ink contained in the pores of the compact block 2 from coming into contact with the user. . According to the second function, it protects the compact block 2 against impact and to do this it must have sufficient resistance to punching and tearing. According to the third function, it is that which serves as a decorative support, for all the technical or commercial indications that it is desirable to bring to the attention of

users.

  In the case where the outer sheath 3 is produced from a transparent film, it is understood that the user will be able to visualize the relative depletion of his article 1, due to the gradual lowering of the ink concentration in

the compact block 2.

  7- In Figure 2, there is shown an article 7 of writing or coloring in

  which ink 8 is in the liquid state.

  The compact block 9 has the same cylindrical shape whose end 9a is conical, terminated by a hydrophilic tip of greater hardness 10, forming writing tip. The compact block 9 has an internal recess 1 1, in which is

injected liquid ink 8.

  The compact block 9 has two distinct zones, the first 12 is

  hydrophilic, while the second 13 is hydrophobic.

  In the example illustrated in FIG. 2, the first hydrophilic zone 12 extends from the central recess 11 to the point 10 and acts as a point

  transfer, connecting the liquid ink tank to the writing tip.

  The second hydrophobic zone 13 materializes the reservoir for the ink

liquid 8.

  The compact block 9 is wrapped in a sheath 2 conforming to the sheath

of article I cited above.

  In this version, the second zone 13 of the compact block 9 acts as a buffer tank, as described in document EP-516,538 of the applicant. More specifically, under normal conditions of use, the liquid ink 8 remains exclusively inside the recess 11. On the other hand, in the event of a variation in the pressure prevailing in the reservoir, due for example to a heating of article 7, the ink can diffuse, by capillary action, inside the pores of the second part 13 of the compact block 9. When the pressure conditions have returned to normal, this excess ink contained in the second zone 13 , returns to the interior recess 11. This is obtained thanks to the channel 21 which connects the zone 13 to atmospheric pressure, allowing the air to escape and thus restore

pressure balance.

  The combination of a first hydrophilic zone and a second hydrophobic zone can be declined according to a multitude of variants. We can for example -8 - predict that the first hydrophilic zone completely surrounds

the central recess 1 l.

  In both versions which have just been described, part

  hydrophilic compact block acts as transfer point and writing point.

  It might be possible that a transfer point, terminated by the point

  of writing, or a separate piece, fitting into the porous compact block.

  The porous compact block of the invention is obtained in particular by thermofusion sintering of microbeads of thermoplastic material (polypropylene, polyethylene, teflon, polyacetal, etc.) used alone or as a mixture, of different grade or nature, depending on the characteristics you want

  give to the different parts of the compact block.

  To carry out the hydrophobic or hydrophilic zones, the sintering operation is followed by a treatment making it possible to bring the surface energy of the materials to a value determined by a plasma treatment for example

  fluorinated or oxidizing as appropriate or by treatment with a surfactant.

  If a treatment with a surfactant is rather envisaged, in this case, there may be risks of dissolution of said surfactant in

  ink, which would affect the functionality of the item.

  The compact sintered block can be obtained by molding or by extrusion followed by machining. These embodiments make it possible to produce compact blocks of all shapes, the cylindrical shape with conical tip given by way of example above not being limiting; we can imagine that said block

  could have a triangular polygonal shape in cross section.

  etc ... DTD: The choice of micro-balls is also determined so that the area of the compact block corresponding to the writing tip has sufficient hardness. The sintering operation is advantageously obtained in an installation where the mold is heated by microwave, thanks to the choice of one or more material (s) which constitute (s) said mold, graphite or silicon carbide for example. The 9- particularity of the use of microwaves is to allow a fast treatment

and at the heart of the material.

  In the simplest version illustrated in Figure 1, the compact block can advantageously be obtained by extrusion, from a given porous material followed by the machining of the end 2a of conical shape terminated by the writing tip . In the example illustrated in Figure 3, article 14 of writing or coloring

  differs from the two previous examples by the covering envelope.

  This envelope is a strip 15 of a complex planar material (multilayer) or monolayer. For example in the case of a complex material, the inner layer 15a which is intended to come at least partially into contact with the compact block is a heat-sealable film, that is to say a film which is capable of adhering to it -even by applying pressure at a certain temperature. The outer layer 15b is a film having good decorating properties, that is to say that it is suitable for being printed. The third layer 15_, sandwiched between the inner layer 15a and the outer layer 15b, is a film impermeable to liquids and gases, which forms a barrier against the evaporation of the ink. This complex strip 15 must have sufficient resistance to tearing and punching to avoid possible damage to the

the article.

  In the example illustrated in FIG. 3, the complex strip 15 has been previously placed around the compact block, being folded back on itself so that its two end edges are superimposed, the inner layers 15a being in contact with the one with the other. Heat sealing is carried out according to the superimposed parts, around the compact block, so as to obtain the closure of the covering envelope over the entire periphery of the compact block.

  except for writing tip 16.

  Under these conditions, it is understood that it is possible, by cutting the extreme edges of the strip 15, to give any aesthetic or utility form to the

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cover film.

  In Figure 3 there is shown an inner cutout 17 which forms a hole for introducing the article 14 on the rod of a display. A second cutout 18 allows, by inserting a blade 19 between the two superposed end edges of the strip 15 before heat-sealing, to provide article 14 with an additional function, namely to allow the user to open his mail

using the article.

  The article 14 of FIG. 3 presents a flat area 20 which corresponds to the heat-sealed area of the two extreme edges of the strip 15. This flat area 20 can preferably constitute a communication space, being printed

  with all appropriate technical and commercial information.

  In the example illustrated in FIG. 5, the part of the compact block which acts as a transfer point 22 and which connects the body 23 of the compact block and the writing point 24 is protected by a protective support 25 in the form of a ring. , which is fitted to the transfer point 22 in the sealing zone 28 of the covering envelope 29. This protective support 25 has the function of ensuring the range of the cap 26, of ensuring the complete sealing of the article 30 when the latter is closed on the one hand by the cap 26 and on the other hand the closure of the covering envelope, in particular by the welding of the complex strip in the sealing zone 28, on the protective support 25 himself. In addition it can have an additional function of allowing the balance of pressures between the interior and

  the outside of the article through an air inlet channel 27.

  The present invention is not limited to the embodiments which have just been described by way of non-exhaustive examples. In particular, the compact block can be covered with two strips of complex material as described above, placed on either side of said compact block and heat-sealed in two longitudinal zones, on either side of said block. Furthermore, the ink-impermeable covering envelope can be

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  obtained by other routes than those explicitly described above. It can be an injected, molded or extruded sheath around the compact block; it may be a film produced by impregnating the compact block and hardening; it can also be a sheath resulting from a modification of the outer layer of the compact block intended to make it impermeable to ink, for example by an appropriate heat treatment. In the latter case, a very pleasant touch of the article is obtained, which can also be an advantage in addition to the lowering of the cost of

raw materials.

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Claims (11)

  1. Writing or coloring article which comprises a body giving it its rigidity and containing a reservoir for the ink, as well as a writing tip supplied with ink from said reservoir, characterized in that the rigid body consists in a compact block (2) of a porous material with open pores also acting as a reservoir for the ink and in that said rigid body is enveloped in a covering envelope (3) impermeable to ink, with the exception of the area   corresponding to the writing tip (5).   2. Article according to claim 1 characterized in that the writing tip (5) is a portion of the compact block, hydrophilic, of determined hardness, shaped in writing tip.   3. Article according to claim I or 2 characterized in that the compact block comprises two adjacent zones, a first zone (12) made of a hydrophilic porous material and a second zone (13) made of a hydrophobic porous material forming a buffer tank, capable of absorb and restore any excess ink in case of   variation of the conditions of use.   4. Article according to claim 3 characterized in that the compact block (9) has an interior recess (11) forming a liquid ink reservoir (8), said recess being connected to the writing tip (10) by the hydrophilic material of the first zone (12) and being formed in the hydrophobic material of the second zone (13).   5. Article according to one of claims 1 to 4 characterized in that the block   compact porous is based on micro-balls in thermoplastic material. whose grade, granulometry, as well as distribution, molecular weight and   the morphology, and in that it is obtained by thermofusion of the microbeads.   6. Article according to claim 3 characterized in that the first hydrophilic zone (12) is obtained by treatment of the compact block (9) after sintering, either by   plasma oxidation, either by deposition of a surfactant.   7. Article according to claim 3 characterized in that the second hydrophobic zone (13) -13- is obtained by treatment of the compact block after sintering, either by plasma fluorination, or by deposition of any other material making it possible to adjust   the surface energy of the material constituting the sintered compact block.   8. Article according to claim 1 characterized in that the covering envelope is a sheath (3) adjusted, obtained using a shrink film. 9. Article according to claim I characterized in that the covering envelope (29) also consists of at least one semi-rigid or rigid strip   arranged around the compact block and heat sealed or glued.   10. Article according to claim 9 characterized in that the semi-rigid or rigid strip constituting the covering envelope is made of a complex multilayer or monolayer material impermeable to ink, the inner face of which is   suitable for heat sealing and whose outer face is waterproof.   11. Article according to claim 1 characterized in that the covering envelope is obtained by modification of the outer layer of the compact block in order to make it impermeable to ink, in particular by heat treatment.