KR100581249B1 - A laminate comprising a thin borosilicate glass substrate as a constituting layer - Google Patents

Abstract

The present invention relates to a laminate in which a thin borosilicate glass substrate is bonded to a support, which is preferably a transparent plastic. The glass substrate protects the support from scratches, moisture, solvents and gases and improves the dimensional and thermal stability of the support while the support protects the glass from fracture. The use of borosilicates significantly reduces fracture properties, for example compared to sodium or chemically cured glass. The laminating method can be used to include a functional layer such as an image recording layer. Laminates are particularly suitable for including electroconductive layers and color filters in flat panel displays.

Description

Laminate having a thin borosilicate glass substrate as a constituent layer {A LAMINATE COMPRISING A THIN BOROSILICATE GLASS SUBSTRATE AS A CONSTITUTING LAYER}

FIELD OF THE INVENTION The present invention relates to laminates having thin borosilicate glass and supports, in particular the laminates comprising an image recording layer and a functional layer such as an electroconductive layer or color-filter layer for use in flat panel displays. It relates to a material having a (fuctional layer).

Plastic materials are widely used as a support for supporting functional layers such as an image recording layer, an electrically conductive layer, a light modulation layer, an adhesive layer, and the like. Many applications require the use of dimensionally stable supports to support functional layers and the like. Known examples thereof are graphic-technology applications and photomasks for the manufacture of printed circuit boards. In these applications glass plates are often used as a support because glass is characterized by good dimensional stability at varying temperatures or humidity compared to plastic supports.

Another example of applications requiring high thermal and dimensional stability is in the manufacture of flat panel displays, such as liquid crystal displays (LCDs), wherein the glass plates are provided with a plurality of color filters, electroconductive layers and liquid crystal alignment layers. It is used as a support for supporting the functional layers. Glass plates used in flat panel displays such as LCDs have a typical thickness in the range of 0.7 to 1.1 mm. At least two glass plates are used for each display and the weight of one display is mainly determined by the size and thickness of these glass plates. In "Fourth Generation LCDs-EIAJ Display Forecast," published in "Display Devices", Spring '96, Serial Numbers 13, pages 14-19 (published by Radio Publisher), the weight reduction of flat panel displays is This is an important need in the art, especially when the displays relate to mobile applications such as portable computers. However, further reducing the thickness of the glass plates is limited due to the high brittleness of the thin glass.

In addition to high thermal and dimensional stability, glass has other beneficial properties compared to plastic materials such as ease of rehabilitation, good hardness and scratch resistance, high transparency, chemistry such as organic solvents or reactive agents. Good resistance to chemicals, low permeability of moisture and gases, and very high glass transition temperatures to enable the use of high temperature treatments to apply functional layers, and the like. However, the major problems associated with the use of glass as a support for the application of functional layers are low flexibility, high specific gravity and high risk of glass breakage, especially when thin glass is used. Due to the low flexibility of the glass, the coating of the functional layer on the glass is typically carried out in a batch process (sheet by sheet), while the coating of the plastic support is generally for example It is carried out in a continuous process using a web or a roll coater. It is apparent that the production and cost efficiency of continuous (web) coating processes is significantly higher than batch (sheet) coating processes.

EP-A 716 339 describes a process using a flexible glass web that can be wound around a core to obtain a roll of glass. The glass may be coated with a functional layer by a continuous web coating method without being wound. The flexible glass has (i) a thickness of 1.2 mm or less, (ii) a failure stress (under tensile stress) equivalent to or greater than 1 × 10 ⁷ Pa, and (iii) an elasticity of equal to or less than 1 × ^{10 11} Pa It is characterized by Young's modulus. In addition, the glass according to the patent is flexible and can be wound around the core. However, the probability of web breakage is high because the sharp local pressure applied on the surface of the glass web is sufficient to break the glass. Although the minimum likelihood of web breakdown is eliminated when coating on an industrial scale, the benefits associated with continuous web coating processes are lost due to interruption of the process.

This problem is also recognized in WO 87/06626, which describes that thin glass with a thickness of 1 to 15 mils breaks almost immediately upon winding. As a solution for protecting the glass web wound around the core, WO 87/06626 intervenes in the use of interleave to prevent glass-to-glass contact. The intercalator is a non-abrasive material such as a molded polyester film. However, if the glass web is released from its core, the intercalator is separated from the glass and the same problems arise as discussed above with respect to EP-A 716 339.

In order to combine the advantageous properties of different materials, it is known to bond the sheets of different materials together to obtain a laminate. A well-known example is safety glass used in vehicle windshields as described in FR 2.138.021 and EP-A 669 205. EP-A-759 565 describes a flexible glass support comprising a color filter for use in a flat panel display, which is laminated on a thin glass pan, characterized by the disadvantages of the laminate as described above (heavy and not flexible). . US 4,105,810 describes coating a substrate with a borosilicate (boron silicate) glass layer by chemical vapor deposition. High temperature is required for chemical vapor deposition and the glass layer is so thin that this technique is not suitable for flexible glass / plastic laminates.
EP-A 669 205 describes glass / plastic laminates comprising a glass pan, an intermediate adhesive layer and a plastic pan (glass thickness is 30-1000 μm). The glass is preferably a chemically cured glass and a functional layer can be added to the glass prior to laminating. After lamination, the functional layer is interposed between the glass and plastic layers to protect it from the external environment. Laminates of thin chemically cured glass and plastic supports have also been described in US Pat. No. 3,471,356. However, thin chemically cured glass is not strong enough to adequately reduce the risk of glass breakage.

Summary of the Invention

The object of the present invention is to characterize the known advantages of glass: high dimensional and thermal stability, good hardness and scratch resistance, good resistance to chemicals such as glass solvents or reagents, low permeability of moisture and gases It is to provide an improved glass-laminate. It is a special object of the present invention to provide a material which has a low specific gravity in addition to the above advantageous properties and which enables the use of a continuous web or roll coating method to apply a functional layer, i.e. a material with sufficient flexible properties and not easily destroyed. The purpose is to. These objects are achieved by a laminate as defined in claim 1, the preferred embodiment of which is specified in claims 2 to 6.

Another object of the present invention is to provide a material in which the laminate is used to support the functional layer. This object is achieved by a laminate as defined in claim 7. Preferred embodiments thereof are specified in the dependent claims.

It is a further object of the present invention to provide a method of making the laminate that supports the functional layer using a web coating apparatus. This object is achieved by the method specified in claims 17, 18 and 19.

Other advantages and embodiments of the present invention will be discussed in the detailed description of the invention.

The laminate of the present invention comprises a thin borosilicate glass substrate and a support. The term "laminate" as used herein should be understood to be "material composed of a plurality of bonded layers". The glass layer and the support layer can be adhered to each other by applying an intermediate adhesive layer between the adhered layers and vacuum lamination can also be used as discussed below. The term "support" is used in the sense of "self-supporting layer" to distinguish it from a layer that can be coated on a support but is not self-supporting.

The glass substrate protects the support from scratches, moisture, solvents and gases and improves the dimensional and thermal stability of the support. Not only does the support protect the glass from breakage, but the borosilicate glass is significantly stronger than regular sodium glass or chemically strengthened glass, as shown in detail below, further reducing the risk of breaking the glass substrate. do.

The dimensional stability of the laminate of the present invention depends on the relative thickness of the glass substrate and the support and the elasticity of these furnaces. Glass is known to have significantly higher dimensional stability than, for example, plastic supports such as poly (ethylene terephthalate). Laminates composed of such plastic supports and glass substrates have significantly improved dimensional stability compared to such plastic supports, and the higher the relative thickness of the glass compared to the support, the better the dimensional stability obtained.

It is preferable that the laminate of this invention is a flexible material. The property of "flexible properties" as used herein means that the material can be wound around the core. Preferred laminates of the invention can be wound around a cylindrical core with a radius of 1.5 m without breaking. The lower the thickness of the glass, the higher its flexible properties, and therefore the lower the minimum radius of the core the material can be wound without breaking. However, the weakness of the glass is inversely proportional to the thickness of the glass and the best compromise between the flexible properties and the weakness depends on the application. The borosilicate glass used in the present invention has a thickness in the range of 10 to 450 mu m. For some applications, thicknesses up to 300 μm or up to 200 μm may be desirable. Because of the low weakness, a thickness of at least 30 μm, or at least 50 μm may be desirable.

The flexible laminates according to the invention can be used in web coating methods for applying functional layers. Since the glass substrate and the support are bonded layers, the laminate of the present invention is to be distinguished from the lamination of non-adhesive layers such as glass / interleaving / glass described in WO 87/06626, above. Although the glass substrate present in the laminate of the present invention is broken due to sharp local pressure on its surface, the glass pieces remain fixed to the support. In addition, the support as a whole prevents the web from breaking and does not interrupt the coating process. In the end, the flexible laminate according to the invention enables, for example, industrial roll-to-roll manufacturing of flat panel displays, thereby significantly reducing the cost of the process.

In addition to the above advantages, the laminate of the present invention combines the advantageous properties of the glass surface with the overall low weight, which is particularly advantageous when the laminate is used as a replacement for glass in portable devices.

Thin borosilicate glass is available from Deutsche Spezialglass AG (Desag, Germany), the Schott Group company, for example a type having a thickness in the range of 30 μm to 1.1 mm. AF45 and D263.

Technical Document "Alkali Free and Alkali Thin Glasses Subtitle" AF45 and D263; Thin borosilicate glass is 30 μm, 50 μm, 70 μm, 100 μm, 145 μm, according to "Thin Glasses for Electronic Application, published by Desag in 1995." Available in thicknesses of 175 μm, 210 μm, 300 μm, 400 μm, 550 μm, 700 μm, 900 μm, and 1000 μm Borosilicate glass includes SiO ₂ and B ₂ O _3. Any borosilicate glass type ( type) has been described, for example, in US Pat. No. 4,870,034, 4,554,259 and 5,547,904.

The higher strength of borosilicate glass compared to other glass types is DIN no. It can be measured by the so-called ring-on-ring method of 52300-5 (= EN 1288-5). This uses a progressively increasing displacement of the ring towards the glass sheet supported by another ring. During this transition, a progressively increasing tensile force is applied on the surface of the glass. The method specified above is not suitable for characterizing thin glass as used in the present invention. However, the inventors of this patent application have demonstrated by final elemental analysis that the method can be modified to be suitable for measuring thin glass; It was found that the tensile strength σ of the glass with the thickness d can be calculated from the maximum force F (max) applied at the moment of glass breakage by the following equation:

Where μ is the Poisson coefficient of the glass And r ₁ , r ₂ and r ₃ are the geometric parameters of the rings used in the experimental measuring devices (6 mm, 30 mm and 58.6 mm, respectively). Further details of the method used can be found in the DIN specification related to the above.

Thirty-two samples of each glass in Table 1 were evaluated using the modified method above, and the average tensile strength σ _m and the corresponding standard deviation S were calculated. Finally, the amount (σ _m - 3S) has been calculated; the - (3S σ _m) - <a, whereas the material to zero as the features that are very easily _{broken, (σ m 3S)> (} σ m -3S) material with a 0 are to have a low likelihood of fracture, The higher the value, the lower the probability of destruction. The borosilicate glass types D263 and AF45 specified above were compared with chemically strengthened sodium glass for the periods shown in Table 1. All samples had a square shape of 100 × 100 mm and a thickness of 70 μm. The results in Table 1 clearly show that borosilicate glass has much better strength than chemically strengthened glass. Another very surprising conclusion drawn from the data in Table 1 is that chemical hardening does not appear to reduce the probability of destruction.

The time when sodium glass was chemically cured Borosilicate 0 min 15 mins 30 minutes 45 mins 60 mins D263 AF45 σ _m -3S (MPa) -840 -260 -760 -560 -1180 +600 (a) +380

(a) The value obtained for D263 is probably too high because the glass loosened from the ring during the measurement, which did not occur for AF45.

A possible description will now be given without limiting the scope of the invention for the inferior results obtained with chemically strengthened glass as compared to borosilicate glass as indicated above. Chemical strengthening, also known as curing of glass, is a well known procedure for increasing the strength of glass. Chemically cured glass is glass in which the original alkali ions in both surface layers are replaced by alkali ions having at least partly a large radius. In chemically cured sodium lime silica glass, sodium ions near the surface of the glass are at least partially substituted by potassium, and in chemically cured lithium lime silica glass, lithium ions near the surface are at least Partly molar by sodium and / or potassium. Further details on the chemical strengthening of glass are given in "Glass Technology", Vol. 6, No. 3, June 1965, pages 90-97. Chemical curing is typically performed by dipping glass in a tank containing molten salt such as potassium nitrate. Such curing conditions are disadvantageous to achieve homogeneous ion exchange at the entire surface of the sheet. Local fluctuations in concentration and temperature and convection or flow caused by the ear canal of the sheet itself interfere with the homogeneity of reaction states in the boundary layer between the surface of the sheet and the chemical curing medium. Heterogeneous hardening results in low fracture stress of the glass, because even if it is a microscopically small area characterized by a low degree of ion exchange, the crack acts as a "weak spot" that can easily begin upon application of a tensile load on the sheet. Results in: However, because borosilicate glass is obtained directly from the melt, it is characterized by a homogeneous composition throughout the entire volume of the glass.

The support laminated to the borosilicate glass according to the invention is paper or metal more preferably cellulose acetate, poly (vinyl acetate), polystyrene, polycarbonate (PC), poly (ethylene terephthalate) (PET), polyethylene, Organic resins such as polypropylene, polyethersulfone (PES), polydicyclopentadiene (PDCP), or copolymers thereof, such as copolymers of acrylonitrile, styrene and butadiene. PET, PC, PES and PDCP are more preferable.

It is preferable that the support has a thickness of 500 µm or less, more preferably 250 µm or less. When the laminate of the present invention is used in high temperature processes, very thin supports, for example having a thickness in the range from 10 to 50 μm, are used to avoid extensive curling of the material due to different thermal contractions or expansion of the glass and the support. It is advantageous to do so. When used in image recording materials or flat panel displays, the support is preferably a transparent support. In a preferred embodiment the adhesive as well as the support is characterized in that it has substantially the same refractive index as glass.

A method of laminating a glass substrate on a support is known. Both layers can be laminated without the use of an adhesive layer by so-called vacuum lamination. In order to obtain an effective bond between the glass substrate and the support by vacuum lamination, it is desirable that all of these materials have a low surface roughness. For example, the support preferably contains no so-called spacing agent, which is sometimes introduced into the coatings on the foils to prevent them from sticking to or in the plastic foils. In addition to vacuum lamination, the use of double-sided adhesive tapes or adhesive layers obtained by applying hot melts or latexes, for example, followed by the use of heat or pressure is highly preferred. The latex is, for example, polyurethane, polyethylene, poly (methyl acrylate) or ethylene-vinyl acetate and the like. Or a slightly wet gelatin layer may also be used as the adhesive layer.

The adhesive layer may be applied to the glass substrate, the support, or both, and may be protected by the peeling layer removed just before the lamination. After lamination, the adhesion between the glass substrate and the support is permanent or reversible. In the latter case, the glass substrate and the support can again be laminated to each other.

The lamination of the glass substrate and the support may be performed manually, but is preferably performed by a laminating means called a laminator. An exemplary laminator has a pair of heatable rollers having an adjustable pressure and moving at a fixed or adjustable speed. Lamination by laminator is achieved by bringing the glass substrate and the support into close contact with each other. An adhesive can be applied between both materials and then passed between the rollers of the laminator.

The adhesive layer can be a temperature-sensitive adhesive (TSA) layer, a pressure-sensitive adhesive (PSA) layer, or an adhesive that is curable or thermally curable by ultraviolet irradiation (UVA), or by exposure to an electron beam. Representative polymers in water-coatable TSAs are latexes having a glass transition temperature (Tg) of up to 80 ° C. If the laminate of the present invention is to be used in a process requiring high temperatures, such as during the manufacture of flat panel displays, suitable TSAs preferably contain a polymer having a Tg at least 10 ° C. higher than the highest temperature of the process. For similar reasons, PSA or curable adhesives that are thermally stable up to a temperature of 150 ° C. or 200 ° C. are preferred.

Preferred PSA layers for use in the present invention are one or more tacky elastomers, for example block copolymers of styrene / isoprene, styrene / butadiene rubbers, butyl rubbers, polymers of isobutylene and silicones. Especially preferred are natural rubbers and acrylate copolymers such as those disclosed in US Pat. No. 3,857,731. The acrylate polymers preferably comprise 90 to 99.5% by weight of at least one acrylate ester and 10 to 0.5% by weight of a monomer substantially selected from the group consisting of oil-insoluble, water-soluble, anionic monomers and maleic anhydride. Do. The acrylate ester moiety is preferably hydrophobic, water-emulsifiable, substantially water-insoluble, and consists of monomers having homogenous glass transition temperatures of 20 ° C. or lower. Examples of such monomers are iso-octyl acrylate, 4-methyl-2pentyl acrylate, 2-methylbutyl acrylate and sec-butyl acrylate. Other examples of suitable monomers include, for example, trimethylamine methacrylamide, trimethylamine pyvinylbenzimid, ammonium acrylate, sodium acrylate, ene, ene-dimethyl-en-1- (2-hydroxypropyl) amine Methacrylamide and anhydrous malane. When applied to untreated paper (paper), the PSA preferably has a continuous coating (100% range) peeling adhesion value (value) between 0.1 and 10 N / cm width.

PSA further contains a binder. Suitable binders are inert to pressure-sensitive adhesives, ie they do not chemically attack the pressure-sensitive adhesive. Examples of such binders are nitrocellulose, urethanes, gelatin, polyvinyl alcohol and the like. The amount of binder should be chosen such that the pressure-sensitive adhesives are laminated effectively. The content of the binder is preferably 2.5 parts by weight or less, more preferably 0.6 parts by weight or less based on the pressure-sensitive adhesives.

UVAs generally fall into two categories: free radical polymerized and cationic polymerized. Polymers formed by free radical polymerization are generally based on acrylic monomers or oligomers converted to high molecular weight polymers by crosslinking upon exposure to ultraviolet radiation. For similar reasons, thermally stable PSAs or curable adhesives up to temperatures of 150 ° C or 200 ° C are preferred. UVA contains a photo-initiator such as benzophenone-amine, alpha-substituted acetophenone or amino-acetophenone. The addition of isopropyl thioxanthone is known to have a photosensitizing effect on photo-initiators and to safely alter useful exposure to near visible light, which is important to the user. Other components typically used in UVAs are flexible agents such as thermoplastics dissolved or dispersed in acrylic materials, adhesion promoters and fillers such as polyethylene or polypropylene. Further information on UVAs can be found in RedCureLetter Volume 5 (1996) and Tappi Journal, January 1992, pages 121-125. Electron beam curable adhesives work on the principle by the same mechanism as UV-curable adhesives but without the need for a photo-initiator.

Examples of suitable adhesives for use in the present invention include Solucryl (Belgium, trade name of UCB), preferably Solucryl Type 355 HP, 380 and 825D; Rhodotak (trade name of Rhone-Poulenc); Acronal (trade name of BASF Corporation); Duro-Tak 380-2954 (trade names of National Starch & Chemical B.V.); PERMAprint type PP2011 and PERMAgard type PG7036 (Belgium, trade name of Varitape N.V.).

The laminate of the present invention comprises at least one thin borosilicate glass substrate and at least one support as constituent layers. In a preferred method for making the laminate of the invention, one or more functional layers are applied on the outer surface of one of the constituent layers of the laminate, preferably using a web coating apparatus. In another method, the support may be first provided with one or more functional layers before being laminated to a thin borosilicate glass substrate. By laminating the coated side of the support to the glass substrate, a support / functional-layer / glass laminate is obtained (optionally including an adhesive layer between the functional layer and the glass). By laminating the opposite side to the glass substrate, a glass / support / functional-layer laminate is obtained. A further drawback of this method is that it must be carried out in the dark room when the functional layer is light-sensitive, for example an image recording layer.

Certain embodiments of higher complexity include a plurality of glass substrates and / or supports. According to the invention, a laminate comprising a thin borosilicate glass substrate and a support S1 is laminated to another support S2 provided with one or more functional layers, so as to obtain a laminate corresponding to one of the following embodiments (this It will be appreciated that embodiments may optionally have an adhesive layer):

-S1 / glass / S2 / function-layer

Glass / S1 / S2 / Function-Layer

-S1 / glass / functional-layers / S2

Glass / S1 / Function-Layer / S2

In both of the latter embodiments, the support S2 can be a temporary support that can be delaminated from the functional layer. Within the scope of the present invention, it is apparent that many combinations of the embodiments can be made, for example, between constituent layers of the laminate as well as laminates having one or more functional layer (s) on the outer surface.

In preferred embodiments, the functional layer is provided on the outer surface of the thin borosilicate glass substrate of the laminate. Prior to applying the functional layer, the surface of the borosilicate glass can be pre-treated, for example etched or pre-coated with a friction layer for good adhesion to the functional layer. Particularly suitable friction layers for this purpose are those based on silicone containing compounds, for example those described in US 3,661,584 and GB 1,286,467. The silicon-containing compound is preferably epoxysilane, and may also be added to the coating composition of the functional layer. The laminate may also be coated with a silicate sol / gel coating having a thickness of at least 1 μm, more preferably at least 10 μm. Such sol / gel coatings are typically applied on sodium glass used in flat panel displays to prevent diffusion of sodium ions to the conductive layer applied on the glass. If alkaline-free borosilicate glass is used in the laminate of the present invention, no such silicate sol / gel coating is necessary.

The functional layer is sputtered, by physical vapor deposition, by chemical vapor deposition, as well as by spin coating, dip coating, rod coating, blade coating, air knife Application on a support or laminate of the invention by coating from a liquid coating solution, such as coating, graver coating, reverse roll coating, extrusion coating, slide coating and curtain coating, etc. Can be. An overview of this coating technology is described in "Modern Coating and" Drying Technology (Edward Cohen and Edgar B. Gutoff Editors, VCH Publishers, New York State, 1992) In New York City). The plurality of layers may be coated simultaneously by a coating technique such as, for example, slide coating or curtin coating. After coating the functional layer (s), the material can be kept in rolls or cut into sheets.

Preferred examples of functional layers which can be coated on the support or on the laminates of the invention are image recording layers such as light-sensitive or thermo-branched layers. Exposure and selective processing of the image recording layer can be before or after lamination. The laminate of the present invention is intended for use in image recording materials that require a high degree of dimensional stability, for example, for materials suitable for making optical masks in the manufacture of integrated circuits by printed circuit boards or photolithography, Especially suitable for graphic art image-sensitive plates or for printing plates such as photolithography pre-sensitized plates, monosheet diffuse transfer reversal (DTR) plates, driographic plates, thermal plates and the like. Photo-sensing compositions of pre-sensitized plates typically contain diazo compounds and can generally be classified into negative-acting forms and positive-acting forms. Negative-acting compositions include, for example, light-sensitive diazo compounds and preferably polymeric compounds. As diazo compounds used in the positive-acting composition, any compounds known in the art can be used, representative examples of which are o-quinonediazides and preferably o-naphthoquinonediazide compounds. These o-quinonediazide compounds may be used alone, but are preferably used as a mixture with an alkali-soluble resin to form a light-sensitive layer.

Representative examples of light-sensitive materials that may include the laminate of the present invention include, for example, black and white materials, color materials, materials for use in medical diagnostics, film materials, diffusion conversion reversal materials, and the like. Silver halide photographic materials composed of at least one hydrophilic layer. Representative silver halide emulsion layers and auxiliary layers are described, for example, in Research Disclosure No. 17643 in December 1978 and in Research Initiation No. 307105 in November 1989. Specific examples of the auxiliary layers are protective layers, filter layers, barrier layers, corrosion layers, back atmospheric layers, anti-rolling layers, antistatic layers, antihalation layers, and the like. Various embodiments of color photographic materials are described in December 1989, initiation of research, 308119. To obtain a flat panel display color filter, the laminate may be coated with at least three silver halide emulsion layers, each of which is exposed to light in a different wavelength region. Further details are given in the Examples.

The laminate of the present invention also has so-called heat-form or heat-sensitive image recording layers because of higher thermal stability compared to plastic supports composed of organic polymers. Preferred thermal sensing layers require a non-wetting treatment, and dry image materials, for example DRAW materials (read directly after writing), so-called dry silver materials or 'Application Photonics Journal', Vol. 9, No. 1, Obtain materials for COM-production (microfilm computer output) as described on page 12 (February 1983). A study of metal layers suitable for use as an image recording layer in DRAW heat-image recording is given in US 4 499 178 and 4 388 400. For the production of optical discs in which information is read in a reflective fashion, a low reflecting heat sensitive recording layer can be applied over a relatively high-reflection layer, such as an aluminum layer.

The thin metal layers are preferably applied by vacuum deposition techniques. In a preferred embodiment of the heat-form recording material, a thin vacuum deposition layer of bismuth (Bi) is used as the heat-form recording layer. Bi is characterized by low toxicity and easily forms a film by vapor deposition under vacuum. The Bi film can be imaged or melted or fused into small particles with a small amount of energy. Further details of this material can be found in EP-B-364 041.

In another embodiment, the heat-form recording layer is, for example, Gravesstein Jr. and Jay. Van del viein, 'Periodical Philips Techn.' Binder-free organic dye layers are obtained, as described in pages 41, 338-346. In another application, the image recording layer is photochromic, as described in Chapter 8 of "Imaging Systems" (see K. I. Jacobson and A. E. Jacobson, Focal Press (1976) p. 143). (photochromic) layer. The image recording layer may also be a photo-lamination layer as described in Research Initiation 22202 (October 1982), pages 328-329. Various printing methods may also benefit from the use of the laminate according to the invention, such as for example an image receiving layer. Examples of such printing methods are electrophotographic (laser) printing, ink jet, toner jet, dye diffusion delivery, thermal wax printing, flexographic printing and screen printing.

The laminate of the present invention may also have one or more non-imaging layers. Examples of such layers are adhesive layers, magnetic layers, firm-coating layers, pigment layers, thermal adhesive layers, ultraviolet-blocking layers, thermoplastic layers and the like. Laminates can also be coated with a layer of phosphorus, allowing higher phosphorus sintering temperatures compared to conventional plastic supports by obtaining a so-called X-ray thickening screen used in medical diagnostics.

Highly preferred functional layers which can be carried out by means of a laminate, preferably by the glass side of the laminate, are color-filter layers used in known liquid crystal alignment layers, electroconductive layers and flat panel displays. The liquid crystal alignment layer typically consists of a mechanically rubbed polyamide film. Films composed of tin oxide, indium oxide or tin-doped indium oxide (ITO) are widely used as conductive layers in flat panel displays because these materials have high transparency in the visible spectrum combined with significantly lower electrical resistance. . ITO, for example, Jay. L. Bossen's Physics of Thin Films, pages 1-71, by high-frequency sputtering from ITO Target, outlined by Academy Press, New York (Plenum Press, 1977), or 'Thin Solid Films', Vol. 83 , 259-260 pages 1981 and 72, pages 369-474 pages 19080, may be coated by reactive direct current magnetron sputtering from an indium-tin target, followed by heat treatment. Suitable color-filter layers for use in flat panel displays are disclosed, for example, in EP-B 396 824 and EPA 615 161.

      The laminate of the present invention is also used with non-contact functional layers, for example pixel electrodes used in conductive rows and columns or thin-film-transistors (TFTs) and active-matrix displays in passive-matrix displays. Like, image or electronic components. For the application of such electronic components on regular sheet glass, screen printing is typically used, but the flexible laminates of the present invention also allow for faster and more reliable patterning techniques such as offset printing. Discontinuous layers may also be formed on the laminates of the present invention by photolithography, laminates followed by delamination, ink jets, toner jets, electrophotography, or thermal sublimation.

Laminates of the present invention are particularly suitable for supertwisted nematic (STN), double supertwisted nematic (DSTN), jersey film supertwisted nematic (RFSTN), etc. ), An excellent substrate for use in the manufacturing process of active-matrix liquid crystal displays in polymer-dispersion (PF), polymer network (PN) liquid crystal displays, and the like. Active-matrix LCDs, such as thin-film-transistor (TFT) displays, can also benefit from the use of the laminate of the present invention as a substrate.

Emissive display technologies that can benefit from the present invention are, for example, electroluminescent displays, plasma displays, field emission displays (FEDs) and so-called light emitting polymer displays (LEPs). LEPs are polymers that glow when exposed to current and are disclosed, for example, in US Pat. Nos. 5,237,190 and 5,401,827.

The laminate of the present invention also makes it possible to obtain modified flexible displays. Flexible displays known today are LCDs in which plastic sheets are used as a support having functional layers. However, the liquid crystal bath and other functional layers between the plastic sheets are not well protected from oxygen, moisture and other external influences, and eventually the lifetime of such flexible displays is limited. Since the glass substrates of the laminates according to the invention are excellent barrier layers, the answer is also provided for this lifetime problem. Since weight reduction is also a major problem in the manufacture of satellites, the use of the inventive laminates for making solar cells also offers interesting advantages.

Example 1

Samples were prepared by the indications in Table 2. All these laminates were vacuum laminates. The length of each sample was measured at 21.5 ° C., both at 30% (L30) and 60% (L60), relative humidity (R.H.) and every% R.H. Percent percentage change per sugar was calculated as: (L60-L30) * 100 / (30 * L30). The results in Table 2 indicate that laminates of polyester (PET) loyl with thin borosilicate glass significantly improve dimensional stability.

        Composition layers (thickness ?? m) "glass" = borosilicate AF45 (a)      Dimensional change (µm / m /% R.H.)   Glass (70)           0   PET (100)          13   Glass 70 / PET 100           3   PET 100 / Glass 70 / PET 100           7   PET 20 / Glass 70 / PET 100           3

   (a) German Special Glass Corporation AG (Desag, Germany), Scott Group Corporation.

Example 2

Type AF45, borosilicate glass sheet of 300x200x0.1 mm dimension, coated with a surrogate layer, so that the dried layer is 1.50 g / m ² of gelatin, 0.1 g / m ² of ortho cresol and 0.4 g / of epoxysilane E m ² was included. The opposite side of the glass sheet was laminated to a polyester foil coated on one side with a polyethylene layer acting as an adhesive layer. The polyester foil had a thickness of 170 μm, a width of 23 cm and a length of 5.6 m, the latter corresponding to the web length of the laboratory cascade-coating machine used in this experiment. In the coater the web forms an endless loop that moves along a triangular passage defined by three rollers having a radius of at least 5 cm. As a comparative example, a similar glass sheet was fixed to another area of the polyester foil with a regular self-adhesive tape over the leading trailing edge of the glass sheet. The foil was then placed in the laboratory web-coating machine so that the gelatin layer was applied onto the glass side of the foil by coating a 5 wt% aqueous solution of gelatin at 38 ° C. containing a surfactant as a diffusing agent. This experiment was repeated 20 times. In 8 of the 20 coating experiments, the taped glass sheet was broken during the coating while none of the laminated glass sheets was broken, indicating a marked increase in the strength of the glass due to the laminate.

Example 3

A color photographic material was prepared by coating an anti-halation layer, a blue sense layer, a first intermediate layer, a green sense layer, a second intermediate layer, and a red sense layer on a 100 μm thick PET film. The composition of the layers is disclosed in EP-A 802 453, wherein the definition of compounds given below is reproduced after this.

Halogen-resistant layer

The non-diffusing yellow dye of Formula YD was dispersed in gelatin. Epoxylene E, which acts as an adhesion promoter, was added to this dispersion. The yellow dyes YD, gelatin and epoxyx E ranged from 0.5, 1.5 and 0.1 g / m ² , respectively.

Blue photosensitive layer

A 100% silver chloride emulsion with an average particle size of 0.4 μm was exposed to blue light with the spectral photosensitizer of Formula SB. A yellow dye was added to this emulsion to form a coupler of Formula Y1. The amounts of silver halide, gelatin and color coupler Y1 were 0.57, 3.30 and 1.0 g / m ² , respectively.

First intermediate layer

The material of Formula SD1 capable of cleaning the oxidized color developer was dispersed in gelatin and coated in the range of 0.08 g / m ² of SD1 and 0.77 g / m ² of gelatin.

Green photosensitive layer

A silver chloride-silver bromide (90/10 molar ratio) emulsion with an average particle size of 0.12 μm was exposed to green light with the spectral photosensitizer of Formula SG. Magenta dyes, which form a coupler of Formula M1, were added to this emulsion. The amounts of silver halide, gelatin and color coupler M1 were 0.71, 2.8 and 0.53 g / m ² , respectively.

Second intermediate layer

This layer had the same composition as the first intermediate layer.

Red photosensitive layer

A silver chloride-silver bromide (90/10 mole ratio) emulsion with an average particle size of 0.12 μm was exposed to red light with the spectral photosensitive agent of Formula SR. Cyan dye, which forms a coupler of Formula C1, was added to this emulsion. The amounts of silver halide, gelatin and color curler C1 were 0.49, 6 and 0.95 g / m ² .

Green, magenta and cyan water soluble dyes acting as accumulator dyes were present in the appropriate range in the blue, green and red photosensitive layers, respectively, and hydroxy-trichloro-triazine serving as a curing agent was red in the range of 0.035 g / m ² . It was in the photosensitive layer.

The back of this material is then laminated to a flexible borosilicate glass sheet of type AF45 having a thickness of 100 μm, thereby obtaining a laminate according to the present invention having a color image recording layer on the PET side of the laminate. Solukryl (Belgium, UCB) Type 355 HP was used as the adhesive between the glass and PET layers. The laminate was then exposed using single-step pixel-type exposure using a multi-color master, which was processed by the following procedure:

developer

4 g of sodium sulfite (anhydrous)

4-amino-3-methyl-ene, en-diethylaniline hydrochloride 3 g                 

17 g of sodium carbonate (anhydrous)

1.7 g sodium bromide

Sulfuric acid 7 N 0.62 ml

1000 ml of water

After development the material was treated in an acid-stop-bath by adding up to 1 liter of water to 50 ml of sulfuric acid 7N.

Treatment with a stop-bath usually followed by a 2 minute rinse in water followed by a 2 minute settling in an aqueous solution having the following composition:

100 ml of 58% aqueous solution of (NH ₄ ) ₂ S ₂ O ₃

Sodium sulfate (anhydrous) 2.5 g

Sodium hydrogen sulfite (anhydrous) 10.3 g

1000 ml of water

Treatment with fixative usually led to a 2 minute rinse in water and 2 minutes bleaching in an aqueous solution with the following composition:

Potassium hexacyanoferrate (III) (anhydrous) 30 g

Sodium bromide (anhydrous) 17 g                 

1000 ml of water

     The material was then retreated with fixative and rinsed with normal water for 3 minutes.

Finally the material was treated with an aqueous solution having a pH of 9 and containing 20 ml per liter of 40% aqueous formaldehyde solution serving as curing agent.

After the treatment, a multi-color filter suitable for FFDs was obtained, with the yellow image, magenta image and cyan image composed of the maximum concentrations respectively. Compared to the prior art, compared to the prior art, for example, as described in EP-A 802 453, where a coating of the same composition on a glass sheet having a thickness of 1.5 mm is described, the multi-color filter of this example is much better. Characterized by low weight.                 

Claims (40)

A flexible laminate comprising a glass substrate and a support, wherein the glass substrate is borosilicate glass having a thickness of 10 to 450 μm. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete The flexible laminate of claim 1, wherein the glass substrate has a thickness of 30 to 300 µm. The flexible laminate of claim 1, wherein the glass substrate has a thickness of 50 to 200 mu m. The flexible laminate of claim 1, wherein an intermediate adhesive layer is present between the glass substrate and the support. 2. The flexible laminate of claim 1 wherein said support is a transparent plastic support. 24. The flexible laminate of claim 23 wherein the transparent plastic support is poly (ethylene terephthalate), polycarbonate, polyether-sulfone or polydicyclopentadiene. 25. The flexible laminate of any one of claims 1 and 20 to 24 further comprising a functional layer. 26. The flexible laminate of claim 25 wherein said functional layer is applied over said glass substrate. 26. The flexible laminate of claim 25 wherein said functional layer is applied over said support. A flexible laminate according to claim 25, wherein said functional layer is a video recording layer. 27. The flexible laminate of claim 25 wherein said functional layer is a color filter. 26. The flexible laminate of claim 25 wherein said functional layer is an electrically conductive layer. 31. The flexible laminate of claim 30, wherein said electrically conductive layer consists essentially of indium tin oxide (ITO). 26. The flexible laminate of claim 25, wherein said functional layer is a discontinuous layer. A flexible laminate according to claim 25, wherein said functional layer is applied using a printing method. 25. The flexible laminate of any one of claims 1 and 20 to 24, wherein the flexible laminate can be wound around a cylindrical core having a radius of 1.5 m without breaking. Preparing a coated support by applying a functional layer on top of the support; And Laminating the coated support to a borosilicate glass having a thickness of 10 to 450 μm; Method for producing a flexible laminate comprising a. Preparing a coated support by applying a functional layer on top of the support; And Laminating the coated support to a laminate comprising a support and a glass substrate that is a borosilicate glass having a thickness of 10 to 450 μm; Method for producing a flexible laminate comprising a. Providing a flexible laminate comprising a support and a glass substrate which is a borosilicate glass having a thickness of 10 to 450 μm; And Manufacturing a flat panel display having the flexible laminate; Method of manufacturing a flat panel display comprising a. A method of coating a web material comprising applying a functional layer on top of a flexible laminate comprising a support and a glass substrate that is a borosilicate glass having a thickness of 10 to 450 μm. A flat panel display comprising a flexible laminate comprising a support and a glass substrate made of borosilicate glass having a thickness of 10 to 450 μm. 28. A method of making a flexible laminate of claim 26 or 27, comprising using a web coating apparatus to apply a functional layer on top of the flexible laminate.