AU651809B2 - Decorative sheets comprising metallized or iridescent plastic flakes - Google Patents

Description

s ee-ts DECORATIVE SFI4TCCOMPRISING METALLIC PARTICLES OR METALLIZED FLAKES.

The invention concerns a decorative sheet used for example in making laminated panels, said sheet comprising metallic particles or metallized flakes. This sheet also may be an overlay sheet. The invention also concerns a composition for imprinting such a decorative sheet.

There are principally two kinds of laminated panels which are presently known: the so-called high-pressure panels and the so-called low-pressure panels.

For many years, laminates have been used in residences, businesses and industrial sites. Typical applications of such laminates are wall surfacing, table tops, furniture coverings, etc.

High-pressure laminates are made from a base consisting of resin-impregnated sheets. As a rule the sheets are kraft paper impregnated with a heat-setting resin, in particular a phenolic resin.

Once the kraft paper has been impregnated with the resin, the sheets are dried, cut, and then stacked one on the other. The number of sheets in the stack depends on the application, and may vary between 3 and 9, but may also be much higher.

A decorative sheet is then placed on the pile of sheets comprising the base.

The decorative sheet as a rule is a sheet of papev which is imprinted with a pattern or 1'.f which is clear, and is impregnated with a heat-setting resin which does not darken when heated, for instance melamine-formaldehyde resins, benzoguanamine-formaldehyde resins, unsaturated polyester resins. In general, a protective cover sheet is placed on top of the decorative sheet, said protective cover being devoid of a pattern and being transparent in the final laminate. In the art, this cover sheet is called the "overlay." This overlay sheet is conventionally manufactured by draining an aqueous suspension of somewhat refined cellulose fibers. The pile of impregnated sheets is then placed into a press furnished with a plate to impart the surface characteristics. Thereafter, the stack is compacted using heat and pressure so as to obtain a unified structure.

During this compaction, the heat-setting resins are converted into the hardened form and an extremely hard material is thus obtained which has a decorative effect.

The so-called low-pressure laminates are made in a similar manner as the manufacture of the high-pressure laminates, but the decorative sheet is directly laminated onto particle board or any other substrate.

Conventionally, the decorative sheet is manufactured in the following manner.

A sheet of paper is made by draining onto a flat table an aqueous suspension of cellulose fibers, which can be long and/or short, bleached and further comprising fillers, retaining agents, binders. The sheet thus formed is drip-drained, pressed and dried to form a sheet of paper. This sheet is then imprinted. The impression which is usually used is a heliogravure impression by means of engraved rollers. The technique of gravure consists of making a design, for instance showing a wood grain or some purely imaginary design.

Then a photograph of this drawing is taken and, using the developed films, one or more printing rollers are engraved. Each roller then passes into an ink bath and the troughs or molds which are etched in the cylinder fill with ink, which is then transferred onto the paper. As a rule, from one to three different and consecutive printings are made with one to three rollers.

Decorative sheets for laminated panels are known, which sheets are imprinted with iridescent mineral pigments. These decorative sheets vary in color depending on the angle of observation. Such sheets have been described in applicant's French patent document A 2,442,719.

Japanese patent application A 63-084,936 of Ibiden describes the manufacture of high-pressure laminated panels comprising an overlay imprinted with an ink S-2containing a glossing agent and a melamine resin binder. The glossing agent consists of a powder coated with titanium oxide. This powder may be, for example, metallic powder, mica powder, or nacreous powder. The glossing agent has particle diameters of from to 60 micrometers. It is mentioned that, if the grain sizes are larger than 60 micrometers the mica suspended in the binder will have the tendency to precipitate. The powder surface is coated with titanium oxide by melting the titanium oxide. The papers obtained according to this Japanese patent application therefore would comprise fairly expensive products, because iN is not easy to obtain particles of sufficiently small granulometry without substantial preparation. Moreover, the procedure of coating by melting of titanium oxide is not easy to carry out.

British patent 1,107,341 of Dow Chemical describes a paper containing a high density of metallic particles consisting of several parallel layers of thermoplastic resins, two adjacent layers having different indices of refraction. This provides for a decorative paper which is not specifically intended to be a laminate; no mention is made of the particles being especially resistant to heat, solvents and light, nor is it possible to use it as a protective sheet without damaging the iridescence.

In the prior art, the effects achieved using powders are uniform because the particles are spherical and of small granulometry.

Moreover, the powders according to the prior art are inconvenient because they easily decant and have only slight covering power due to their spherical shape and small granulometry.

According to known procedures, it is common to use aluminum powder to create a decorative effect. However, if the aluminum em44comes into contact with water, 1+ 6ec me-- oy 3 as ec\ hydrogen is released, which is obviously dangerous; furtherm re, aluminum tarnishes and hence loses its metallic gloss; such particles are applicable only in a very restricted way.

The particles also are subjected to high temperatures on the order of about 1600C when the sheets are laminated.

Moreover, when being used, the laminates often are exposed to natural or non-visible light over prolonged periods. For example, the applicant has described, in its French patent application A 89 05541, a sheet intended to be exposed to light for a prolonged time, which sheet takes on a first tint when in natural light of a wavelength between 400 and 800 nm, and a different, seoond tint when exposed to non-visible light -3 A .b li 4 having a wavelength of less than 400 nm and longer than 800nm; this print comprises at least one luminescent pigment.

Another problem arising from the use of iridescent particles of the prior art in high-pressure laminates is that a standard overlay sheet (that is an undecorated sheet) cannot be used with a decorative sheet comprising these particles because the overlay sheet excessively attenuates the decorative optical effect of the particles. Accordingly, the laminate quality is low because it lacks an overlay sheet to protect it, in particular against abrasion.

The object of the invention is to overcome these drawbacks.

It would be desirable to create a sheet for use in laminates and which has a metallic effect, with various sizes, tints and shapes that can be selected in relation to the desired decorative effects.

It would also be desirable to use glossy particles with a covering power which exceeds that of the conventionally used powders and which does not easily decant.

Further, it would be desirable to introduce the particles, either in bulk into the sheet during manufacture of the sheet, for example by a papermaking i "procedure, or by imprinting this sheet with an ink containing these particles, a binder and a '"binder-solvent. Consequently, these particles must be suitable for use in an aqueous medium and/or in a 30 non-aqueous solvent medium; they must be inert relative to the selected medium.

coo :o It would also be desirable to deposit the particles during the impregnation of a heat-setting resin, said deposition being uniform and homogeneous.

It would further be desirable to make printed i; i 5 products which are fast against natural or artificial light.

One approach of the invention is to use metallic particles or metallized flakes, which are glossy and which withstand water and/or non-aqueous solvents, heat and natural or artificial light.

To achieve the goals of the invention, particles may be used which have been cut from thin sheets. These particles may have various geometric shapes, for example, they may be hexagonal, rectangular, square or star-shaped. Their sizes may also vary. The gloss will be higher as their size increases. Preferably, the largest of the particle dimensions shall exceed micrometers, and more preferably, it shall be at least 100 micrometers.

These varied shapes and sizes offer the advantage of allowing much varied decorative effects as already mentioned above.

The sheet of the invention may be used as a base sheet to make a printed product comprising luminescent pigments.

Accordingly the invention provides a sheet for use in a laminate which has a decorative metallic effect, wherein the sheet comprises metallized flakes or metallic S 25 particles which are inert to Zrascater, which withstand V. 0 I "'"temperatures exceeding 100 C and which are covered with a protective layer of lacquer which is fast to natural or artificial light.

The metallized flakes or metallic particles for use 30 in the invention can be made by cutting them from a metallized plastic film. The metallic layer may be coated *...with a protective cover. The metal used is preferably 4 aluminum. The film is preferably polyester. The flakes 4 may be obtained by cutting a highly polished aluminum sheet also covered with a protective layer of lacquer.

f j i 6 This protective layer is preferably an epoxy resin lacquer.

These flakes may be colored. The flakes may be of metallic hue, for example, gold or silver, and they may be of one color or multicolored.

The thickness of these particles is approximately micrometers, and their shapes and sizes may vary.

The sheet of the invention preferably has a base of cellulose fibers. It may be colored. It may also contain non-cellulosic fibers, for instance polyester or polyolefin fibers.

The invention provides a sheet for use in laminates which has a decorative metallic effect. The metallized flakes or metallic particles may be introduced dur!)g the course of its manufacture. The flakes or particles can be added to an aqueous suspension containing cellulose fibers, the mixture next being dripped onto a canvas, the sheet thus made then being pressed between the drums and dried. Tis sheet may be imprinted to achieve conventional decorative effects (fake wood, fake marble, etc.). The decorative effect is emphasized by the metallization of the substrate sheet.

Finally, the flakes or particles may be added by dusting or scattering while the sheet is being impregnated with a heat-setting resin when the impregnating resin still is liquid, and thus has not yet hardened.

For example, a powdering device made by Pillon-Andriot Co. and patented under EP A 307,318 may be used.

The invention also provides a sheet for use in laminates which has a metallic effect, the metallic particles or metallized flakes being applied to the sheet ee@ by photo-gravure with an ink containing said particles.

The sheets produced according to the invention may be impregnated with a heat-setting resin.

The invention provides an ink composition for photo-engraving a laminate sheet which has a decorative 6a metallized effect, which is characterized in that it comprises: at least some metallized flakes which are inert to PocefI;rc-h water, and which withstand temperatures in excess of 100 0

C,

at least one (meth)acrylic or vinylic binder, at least one solvent.

This solvent may be an alcohol, water, or a water-alcohol mixture.

This ink may contain rheological control agents.

The invention also provides another ink composition which comprises: at least some metallized flakes which are inert in fresh water, and which withstand temperatures in excess of 100 0

C,

at least one casein-based aqueous binder, at least one agent rendering casein insoluble, at least one water/alcohol solvent.

Applicant has surprisingly discovered that the decorative optical effect provided by a sheet adorned with flakes selected for the invention is not altered by the addition of a standard overlay sheet. Accordingly, the invention also provides laminates comprising a decorative sheet having a metallic effect due to metallized or 25 metallic particles or to metallic particles which are inert to aqueous or non-aqueous solvents and which withstand temperatures in excess of 100 C and which may also comprise a protective overlay sheet.

S:"The invention furthermore allows the production of 30 laminates comprising a decorative sheet having, a decorative metallic effect and comprising the above described metallic, metallized particles, said sheet being covered by an overlay sheet to protect it and which could also be adorned with the above described particles.

The invention will be better understood with the aid of the following examples.

EXAMPLES

EXAMPLE 1 A gravure ink is made by mixing: metallized flakes: 5 parts flakes made from a metallized polyester sheet with epoxy enamel protector, silver in color, 100 x 100 x 12 m, made by Dragon-Werk and sold by Chemilab Essor, a solvert: 30 parts ethylglycol to achieve a viscosity adapted to the particular printing machine being used, a binder: 65 parts vinyl lacquer sold by SIPCA (15 dry weight).

This mixture is applied to a 80 g/m 2 paper sheet, black in color, by photogravure printing. Approximately 3 g/m 2 (dry weight) of flakes are deposited.

A decorative sheet with a decorative metallic effect is obtained in this manner.

This sheet is used to manufacture a high-pressure laminate without an overlay: 3 sheets of kraft paper impregnated with phenol resin of 120 g/m 2 are used, the decorative sheet of the invention is then deposited on the above three sheets, the assembly is laminated by heating it to 130°C for 30 minutes under a pressure of 100 MPa (100 kg/cm 2 A laminate with an intense metallic effect is thus achieved.

-7- EXAMPLE 2 Another high-pressure laminate is made using the decorative sheet obtained according to Example 1 by adding a melamine-resin impregnated 28 g/m 2 overlay sheet to said sheet.

The lamination is carried out as above. A laminate havin a metallic effect as intense as the laminate made without an overlay is obtained.

The selected metallized particles and the ink that was used permit the manufacture of a decorative sheet of which the metallic effect is unaffected by the presence of a protective overlay; the particles withstood well the operational conditions.

EXAMPLE 3 A photo-gravure ink is made by mixing: metallized flakes: 4 parts flakes from a metallized polyester sheet with epoxy protective enamel, silver in color, 100 x 100 x 12 rm, made by Dragon- Werk and sold by Chemilar Essor, a solvent: 7 parts (water/ethanol) to achieve a viscosity adapted to the particular printing machine being used, a binder: 87 parts casein-based aqueous lacquer (13 dry weight) sold by

SICPA,

a casein insolubilizer: 2 parts formol.

This mixture is applied to an 80 g/m 2 sheet of paper, black in color, by photogravure. Approximately 3 g/m 2 (dry weight) of flakes are deposited.

To enhance grip of the flakes, a coat of protective lacquer with the same ingredients as the above ink, except for the flakes, may be deposited.

This sheet is used to make a high-pressure laminate, without an overlay, as in Example 1.

A laminate with an intense metallic effect is obtained.

EXAMPLE 4 An overlay sheet according to the invention is made. To an aqueous suspension of cellulose fibers are added 15% (dry weight relative to the fibers) of flakes of an aluminum-metallized polyester sheet which has been covered with an epoxy enamel.

These flakes are multicolored.

Thereupon, this mixture is placed in a papermaking machine to form a sheet having a weight of 60 g/m 2 Next, a high-pressure laminate as described in Example 1 is produced using a solid black decorative sheet and the overlay sheet described above.

A laminate with an iridescent eff-ct is obtained. This laminate withstands abrasion and the particles hold up well.

EXAMPLE A paper for use in laminates is made from a suspension of cellulose fibers to which the following are added: 10 mineral fillers (kaolin or talc), 5 of stabilized aluminum paste R. Silvex 1537 or 1258, sold by Carbonnel Jacquemot, France), optionally, about 3 of an organic or mineral pigment which is conventional for laminate papers, 1.5 of formol melamine resin to provide moisture resistance, 1 aluminum sulfate as a retention agent.

The pH is adjusted to 7 using sodium carbonate or calcium carbonate.

The paper sheet is formed and dried, and impregnated with a formol melamine resin. Lamination is carried out as in the above Examples, with or without an overlay, A panel with the appearance of metallic paint is obtained. This metallic appearanne is as intense for the panel with an overlay as for "he panel without an overlay.

-9-

J

EXAMPLE 6 A sheet is made as in Example 5, but it is imprinted after having been dried, in order to achieve a marble decoration. Impregnation and drying take place as described above.

When comparing a panel of the invention with a panel made from a decorative sheet lacking the aluminum paste, it is unexpectedly found that the imprinted decoration is enhanced by the sheet metallization.

Claims (16)

1. A laminate sheet having a decorative metallic effect, characterized in that it comprises mstallized flakes or metallic particles which are inert to erl water, which withstand temperatures in excess of 100 C and which are covered with a protective layer of lacquer which is fast to natural or artificial light.

2. The sheet according to claim 1, characterized in that the metallized flakes are obtained by cutting them from a plastic film metallized with aluminium and covered by a protective layer of lacquer.

3. The sheet according to claim 2, characterized in that the plastic film is a polyester film.

4. The sheet according to claim 1, characterized in that the metallized flakes are obtained by cutting them from a highly polished aluminium sheet covered by a protective layer.

The sheet according to claims 2 through 4, characterized in that the protective layer is an epoxy 20 lacquer.

6. The sheet according to any one of claims 1 through characterized in that the largest dimension of the metallized flakes is greater than 80 micrometers.

7. The sheet according to any one of claims 1 through 6, 25 characterized in that it is further comprised of cellulose fibers and is optionally colored.

8. The sheet according to any one of claims 1 through 7, characterized in that the metallized flakes are applied in a layer to the sheet by photo-gravure with an 3> ink containing the flakes.

9. The sheet according to any one of claims 1 through 7, o* characterized in that the metallized flakes or metallic particles are added in bulk to the sheet during the manufacture of the sheet by a papermaking process.

10. The sheet according to any one of claims 1 through 9, 12 characterized in that it is impregnated with a heat-setting resin.

11. The sheet according to claim 10, characterized in that the metallic particles are deposited uniformly following impregnation with the resin but before the resin is heat-hardened.

12. An ink composition for imprinting a sheet according to any one of claims 1 through 8, by photo-gravure, characterized in that it comprises: at least some metallized flakes which are inert pure- relative to fesih-water, and which withstand temperatures in excess of 100 0 C, at least one (meth)acrylic or vinylic binder, at least one alcohol solvent.

13. An ink composition for imprinting a sheet according to a-y one of claims 1 through 8, by photo-gravure, characterized in that it comprises: at least some metallized flakes which are inert in pore- freshiwater, and which withstand the effects of 20 temperature in excess of 100 c, at least one casein-based aqueous binder, at least one insolubilizer, at least one water/alcohol solvent.

14. A laminate sheet having a decorative effect according t 25 to any one of claims 1 through 11 further including a protective overlay sheet.

15. A laminate sheet having a decorative metallic effect ooo as hereinbefore described with reference to any one of the Examples. 30

16. An ink composition s hereinbefore described with reference to any one of the Examples. DATED this 5th day of May 1994 ARJO WIGGINS SA Patent Attorneys for the K Applicant: F.B. RICE CO. .NTERNATIONAL SEARCH REPORT International Application No PCT/FR91/00084 I. CLASSIFICATION OF SUBJECT MATTER (if several classification symbols apply, Indicate all) According to International Patent Classification (IPC) or to both National Classification and IPC IPC 5 B44F 1/14, B44C 5/04 II. FIELDS SSARCHED Minimum Documentation Searched 7 Classification System I Classification Symbols IPC 5 B44F, B32B Documentation Searched other than Minimum Documentation to the Extent that such Documents are Inr.uded In the Fields Searched III. DOCUNIENTS CONSIDERED TO BE RELEVANT Category Citation of Document, It with Indication, where appropriate, of the relevant passages 12 Releva o Claim No. 13 Y FR, A, 2442719 (ARJOMARI-PRIOUX) 27 June 1980 1,2,7-10 see page 1, lines 14-17; page 3, lines 13-33; page 4, lines 5-20 A 11-13 (cited in the application) Y GB, A, 1107341 (DOW) 27 March 1968 1,2,7-10 see page 1, lines 76-87; page 2, line 85 page 3, line A 6 (cited in the application) A GB, A, 786667 (RAINBO-CEL) 20 November 1957 1-4,7,15,16 see page 2, lines 3-21; page 2, line 63 page A US, A, 3785911 UNGAR) 15 January 1974 1 see column 1, lines 52-67; column 2, lines 3-17 A US, A, 4769265 (COBURN) 6 September 1988 17 see claims 1,4,8 A GB, A, 469754 (DUPONT) 28 October 1935 16 see page 3, examples 10-12 Special categories of cited documents: to later document published after the International filing date document defining the general sate the art which is not or priority date and not In conflict with the application but document defining the general sate of the art which Is not cited to uriderstand the principle or theory underlying the considered to be of particular relevance invention earlier document but published on or after the international document fI particular relevanca; the claimed Invention filing date cannot be o)nsidered novel or cannot be considered to document which may throw doubts on priority clalm(s) or involve an InkJntive step which is cited to establish the publitatlon date of another document of particular relevance;' the claimed invention citation or other special reason (as specified) cannot be considered to involve an inventive step when the document referring to ,n oral disclosure, use, exhibition or document is combined with one or more other such docu- other means monts, such combination being obvious to a person skilled document published prior to the International filing date but in the a r t i later than the priority date claimed document member of the same patent family IV. CERTIFICATION Date of the Actual Completion of the International Search Date of Mailing of this International Search Report 28 May 1991 (28.05.91) 16 August 1991 (16.08.91) Internatlonal Searching Authority Signature of Authorized Officer European Patent Office Form PCT/ISA/210 (second sheet) (January 1985) ANNEX TO THE INTERNATIONAL SEARCH REPORT ON INTERNATIONAL PATENT APPLICATION NO. FR 9100084 SA 44734 This annex lists the patent family members relating to the patent documents cited in the above-mentioned international search report. The members are as contained in the European Patent Office EDP file on 26/07/91 The European Patent Office is in no way liable for these particulars which are merely given for the purpose of information. Patent document Publication Pat- -t family Publication cited in search report date niemberC.5) date FR-A- 2442719 27-06-80 None GB-A- 1107341 None GB-A- 786667 None Lci-A- 3785911 15-01-74 None US-A- 4769265 06-09-88 JP-A- 59127752 23-07-84 GB-A- 469754 None 0 W For more details about this anxtex see Official Journal o1 the European PateawOffice, No. 12182 RAPPORT DE RECHERCHE INTERNATIONALE Demands Internationale N- PCT/FR 91/00084 1. CLASSEMENT DE LINVENTION (si plusiturs syrnooles de classirication sont opplicable%, Its Indlauer tout) Solon I% classification intornotionale des brovets (CIS) ou h Ia tois selon Is classification nationals at la CIS CIB 5 B 44 F 1/14, B 44 C 5/04 11, DOMAINES SUR LESQUELS LA RECHERCHE A PORT11 Documentation mlnimale consultde I Systlme do clasification Symboles do classification C18 5 B 44 Fr B 32 B Documentation consulthe autro quo Ia documontation minimale dons I& mosure otO do tl documants font pantie des domainos Sur $osquols Ia recherche a ponti I Ill, DOCUMENTS CONSI~tR95 COMME PERTINENTS Cotigorie *Idonticatlon dos documents clii," avoc Indication, si niceasairo, N, des rovondlcations Ides passage% portinents t' visits 'a Y FR, A, 2442719 (ARJOMARI-PRIOUX) 27 juin 1,2,7-10 1980 voir page 1, lignes 14-17; page 3, Jlignes 13-33; page 4, ligries 5-20 A 11-13 cite- dans !a demande Y GB, A, 1107341 (DOW) 27 mars 1968 1,2,7-10 voir page 1, lignes 76-87; page 2, ligne 85 page 3, ligne Cit6 dans la demande A GB, A, 786667 (RAINBO-CEL) 20 novembre 1957 '-4,7,15,16 voir page 2, lignes 3--21; page 2, ligne 63 page A US, A, 3785911 LNGAR) 15 janvier 1 voir colonne 1, lignes 52-67; colonne 2, lignes 3-17 Catigories apiciales do documents cis~z 11 %T s document ultilur oubIi4 PoaterleuraentA ls dote do dioit aA s documnent dilinissont 1'6tat gbniral do Is techinique, non International ou A to date do priorite ot nappononn Pat conaiddril comma particuliramont pertinent I li4tat do Ia^ techniqueo prtsnont, mais cit* pour comprondf S Is Prinipe ou Is thilorie constituent Io base do Pinvonition o Es document antiriour, mois pubilik 6 )a date do* dipit Inferns- a X i, document partlculfirment pertinent', lInvontion tovenl tional ou apris 'at's dote ouie no pout firs considirie comina nouvollo ou commao a( Lu document pouvant later un doute sur une reondicatlon do Impllquant un. activiltiInventive priorati izu cite Pout ditorminer Io dote as pujblication d'une Y s document particulliroment pertinent, Pirnventlon raven. suit# citation cu pour uns raison apiciaoe (tetlo qu'lndlquis) dlquto no pout itre conaldirie comma Inipliquant une o 0s document so rifirant jk uno divulgatiporoate, A un ussge, A activiti Inventive laraque Is document *at associi A un ou uno exposition ou tous Outres mayens plusiours aull., documents do mime nature, cante combl- a Pa document pubili~ awant Is dote do dip6t international, mats naion Atant ividento Pour uno porsonnot du riftior. pothiourement A to date 0o prloriti rovondiquilt a A document Slut falt partis do ts mime famillo do brewers IV, CERTIFICATION Dgo A lartuolle Is recherchse Internationol* it M efloctlvemont Date d'espidition du prevent rapport do recherchi nternationale 28hv~ mai 1991 t6. 08. qi Adminiafrotion cttargi. do to recherche wtetrnstlonalo Signature du toni: R I*.r 0~ OFFICE EUROPEEN DES BREVETS 00 TORIBIO Formulairo PCTIISA/210 (dousti'vs fouilt.) (,ansro 105) Demand* Internationale N, PCT/FR 91/00084 -2- (SUITE DES MENSEIGNIMENTS INDIQUtS SURt LA 111, DOCUMENTS CONSID9Rd5 COMWE PERTINENTS IOEUXIItNE FEUILLE) Cattgorie oetta no ouot ofao niacn ino sis e d tos de oassages Witnonts i US, A, 4769265 (COBURN) 6 septembre 1988 voir revendications 1.,4,8 GB, A, 469754 (DUPONT) 28 octobre 1935 voir page 3, exemples 10-12 Form-,' ire Pf'T 'IS 210 (f..hil dditionr li.1 it nvW19-4I ANNEXE AU RAPPORT DE RECHERCHE INTERNATIONALE RELATIF A LA DEMANDE INTERNATIONALE NO. FR 9100084 SA 44734 La prisente annexe indique les inetbres dec ]a famille dec brevets relatifs aux documents brevets citis dans le rapport dec recherche internationale vise ci-dessus. Lesdits mezabres sont contenus au fichier informatique de 1'Office europien des brevets si I date du 26107191 Les, renseignesnents fournis sont donnks i titre indicatif et n'engagent paus in responsabilitl de l'Office europiecn des brevets. Document brevet cit6 Date dec Membre(s) dec la Date dec au rapport de rchierche publication fanille dec brevet(s) publication FR-A- 2442719 27-06-80 Aucun GB-A- 1107341 Aucun GB-A- 786667 Aucu n US-A- 3785911 15-01-74 Aucun US-A- 4769265 06-09-88 JP-A- 59127752 23-07-84 GB-A- 469754 Aucun Pour tout renseignement concernant cette annexe voir Journal Officiel dc 1'Office europslen des brtvets, No.12/B2