JP2002023649A - Transparent impact relaxation laminated body and display device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impact relaxation laminated body which is thin and lightweight and has high preventing property against cracks in a panel by laminating a shatterproof layer 5 and crack preventive layers 1, 2 for the glass with a transparent pressure sensitive adhesive layer 3 interposed to integrate with a panel 4 or by inserting an electromagnetic wave shield layer and a near IR ray shield layer into any desired layers. SOLUTION: The transparent impact relaxation laminated body is formed on a glass panel substrate of a display device which can be broken by impact force by dropping a steel ball which corresponds to 79,000 N (at 1.5 m height with 510 g weight). The laminated body has a shatterproof layer 5 having >=2×108 Pa shear elastic modulus, two or more kinds of crack preventive layers 1, 2 having different shear elastic moduli from each other in the range from 1×104 to 2×108 Pa, and a transparent pressure sensitive adhesive layer 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to flat panel displays (hereinafter abbreviated as FPDs), such as FEDs and PALs.
C, LCD, PDP, and the like. In particular, a glass substrate of a panel itself, which is attracting attention as a large display, has a thin glass substrate and is easily broken. Laminate the shock-mitigating laminate to reduce the impact force caused by falling of a steel ball equivalent to 79000N, and to prevent the scattering and cracking of the shock-mitigating laminate and the electromagnetic wave and near-infrared rays, especially 800-1200nm, generated from PDP. The present invention relates to a filter for shielding and a PDP panel display device having the filter attached thereto.

[0002]

2. Description of the Related Art Glass cathode-ray tubes (cathode ray tubes) are used for televisions and displays according to safety standards (UL standards, the Radio Control Law, etc.). The size of the panel glass should not cause electric shock), and it was necessary to design the panel glass thicker. With respect to such a CRT glass panel, a synthetic resin protective film (thermosetting urethane resin and polyester film PE) having self-healing properties as a means of weight reduction without increasing the thickness of the glass panel.
T) is laminated as a glass cathode ray tube.
No. 33515 and Japanese Patent Application Laid-Open No. 06-333517 have been proposed. This proposal is characterized by anti-scattering properties, but does not have a function of preventing breakage of the glass panel substrate.

As a protective filter, Japanese Patent Application Laid-Open No. 11-1
Japanese Patent Application Laid-Open No. 74206 discloses a transparent resin sheet for protecting a glass substrate inside a flat panel display (various liquid crystal displays (LCDs), PDPs).
It has been proposed to protect the glass of the panel itself with a front protection substrate installed within m.
Since an air layer enters between the glass panel and the protective substrate, there are many problems such as double reflection of external light, an increase in reflectance, and a decrease in image quality due to parallax. Further, in the above proposal, since there is an air layer, dust, cigarette tar and the like accumulate in the voids, and cleaning is also difficult.

[0004] Furthermore, in PDPs where it is important to increase the size and weight, there is a tendency for the panel itself to be thinner, and installing a protective filter away from the panel has an adverse effect. That is, in a large PDP display or the like, a protective filter that is thin and lightweight and that prevents the panel from cracking has not been realized yet.

[0005] Further, the PDP generates electric discharge in a rare gas enclosed in the panel, especially a gas mainly composed of neon.
The R, G, and B phosphors provided in the cells inside the panel are caused to emit light by the vacuum ultraviolet rays generated at that time. In this light emission process, electromagnetic waves and near infrared rays unnecessary for the operation of the PDP are simultaneously emitted. Especially the electromagnetic wave is VCC
Since radiated electromagnetic waves are regulated by I and FCC, etc., and there is a concern in recent years that electromagnetic waves have a negative effect on the human body,
It is necessary to shield the electromagnetic waves emitted from the PDP.

[0006] With respect to the near infrared, the wavelength range of the emitted near infrared is approximately 800-1200 nm. On the other hand, the light-receiving elements of infrared sensors used in remote control devices such as household appliances, karaoke equipment, and audio-visual equipment often have peaks of light-receiving sensitivity at about 700 to 1300 nm, and thus are emitted from PDPs. Since there is a problem that the received near-infrared rays cause the remote controller to malfunction, it is necessary to cut off near-infrared rays generated from the PDP.

[0007] From such a background, there is a demand for a filter for cutting electromagnetic waves and near-infrared rays generated from a PDP. For example, an acrylic plate in which a metal mesh is embedded or a patterned mesh is processed by etching; A transparent multi-layer thin film laminate having a structure in which a metal thin film layer is sandwiched between transparent thin film layers and the like, as well as an electromagnetic wave / near infrared cut molded plate in which a dye that absorbs near infrared light is added.

[0008] Application of such a metal mesh, a patterning mesh and a transparent multilayer thin film laminate to a PDP filter has been studied. In general, filters used in display devices such as PDPs include PDPs having 10
It is formed of a glass substrate or a front plate structure such as acrylic, which is separated from the PDP panel by a distance of less than 1 mm, and is not directly adhered to the PDP panel via the transparent adhesive layer. There was a problem that the glass substrate was broken.

[0009]

SUMMARY OF THE INVENTION In view of the above problems of the prior art, the present invention has two or more transparent layers composed of a scattering prevention layer and a crack prevention layer directly on a PDP panel via a transparent pressure-sensitive adhesive layer. A first object is to provide a shock absorbing laminate and a display device using the same.

A second object of the present invention is to improve the prevention of scattering and breakage of glass, and to prevent electromagnetic waves and near-infrared rays by laminating a filter containing an electromagnetic wave shielding layer and / or a near-infrared ray shielding layer. And directly adheres to the glass panel itself to improve the sharpness of the image. Furthermore, there is no air layer between the panel and the shock-absorbing sheet, and there is no double reflection of external light, and dirt such as dust and dirt is removed. Provided are a transparent shock-mitigating laminate that does not reach and a display device using the same.

[0011]

In order to achieve the above-mentioned object, the transparent shock absorbing laminate of the present invention is provided with a 79,0
A transparent shock absorbing laminate formed on a glass panel substrate of a display device that is destroyed by an impact force equivalent to 00N (height: 1.5 m × weight: 510 g), wherein the laminate has a shear modulus of elasticity. A scattering prevention layer having a shear modulus of 2 × 10 ⁸ Pa or more, a crack prevention layer having a shear modulus in a range of 1 × 10 ⁴ to 2 × 10 ⁸ Pa and two or more different shear modulus, and a transparent pressure-sensitive adhesive layer And characterized in that:

It is preferable that the transparent shock absorbing laminate of the present invention further comprises a transparent electromagnetic wave shielding layer and / or a near-infrared shielding layer having a transmittance in the range of 800 to 1200 nm of 20% or less.

[0013] The transparent shock absorbing laminate of the present invention has a total thickness of a transparent shock absorbing laminate comprising a transparent pressure-sensitive adhesive layer, a crack preventing and scattering preventing layer, and an electromagnetic wave shielding layer and / or a near infrared ray shielding layer of 5 mm or less. And its visible light transmittance is preferably 40% or more.

[0014] Further, the transparent impact-relieving laminate of the present invention comprises 7900
It is preferable to reduce the steel ball drop impact force corresponding to the impact force of 0 N to 50% or less.

Further, the transparent impact-relieving laminate of the present invention comprises at least three of the anti-scattering layer and the anti-cracking layer described in any of the above. The order of lamination of each crack prevention layer is the ratio of the shear elastic modulus of the upper and lower layer materials in contact with each interface of the crack prevention layer shown in the following formula (B). It is preferable that the sum of the absolute values of the logarithms is the largest, and that it has scattering prevention and crack prevention. (A) Transparent impact-mitigating laminate: anti-scattering layer (1) / anti-cracking layer (2), anti-cracking layer (3) ... anti-cracking layer (n) / adhesive layer (B) Shear modulus (G) ) Sum of absolute values of logarithm of ratio: | Log G1 / G2 | + | Log G2 / G3 | + ... + | Log Gn-1 / Gn | +
| Log Gn / G pressure-sensitive adhesive layer | The transparent shock-mitigating laminate of the present invention has an electromagnetic wave shield and / or an anti-reflection or anti-reflection protection layer based on a pressure-sensitive adhesive layer / break prevention layer / scatter prevention layer / anti-reflection or reflection prevention protection layer. Preferably, a near-infrared shielding layer is included in the basic structure.

Further, the transparent impact-reducing laminate of the present invention is preferably a filter for a plasma display.

Next, a plasma display device according to the present invention is characterized in that the transparent shock absorbing laminate according to any one of the above is laminated.

According to a second aspect of the present invention, there is provided a flat display device comprising the transparent shock-absorbing laminate according to any one of the above.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION As a result of intensive studies, the present inventors have found that
The anti-scattering and anti-crack transparent shock absorbing laminate of the present invention is a glass panel of a display device which is broken by an impact force equivalent to 79,000 N (height: 1.5 m × weight: 510 g) due to falling of a steel ball. A transparent shock-mitigating laminate formed on a substrate, wherein the laminate comprises a scattering prevention layer having a shear modulus of 2 × 10 ⁸ Pa or more, and a shear modulus of 1 × 10 ⁴ to 2 × 10 ^8. It has been found that a transparent impact-reducing laminate comprising a crack-preventing layer in the range of Pa and having two or more kinds of different shear modulus and a transparent pressure-sensitive adhesive layer is formed. More preferably, a transparent electromagnetic wave shielding layer and / or
Alternatively, it has been found that a plasma display filter including a near-infrared shielding layer having a transmittance in the range of 800 to 1200 nm of 20% or less and a plasma display device in which the filter is bonded via a transparent adhesive layer.

The present inventors actually dropped a steel ball of about 510 g from a height of 1.5 m from a height of 1.5 m and actually measured the impact force of 79000 N using a force sensor with reference to safety standards. Further, a destructive test was performed on the glass substrate for FPD by dropping a steel ball, and a limit impact force (or an impact force that does not break) at which the glass substrate was broken was measured. The impact relaxation rate was determined as to the extent to which the impact force should be relaxed by the impact relaxation laminate with respect to the limit impact force at which the crack occurs.

That is, the shock absorbing laminate has a basic structure of a scattering prevention layer / a crack prevention layer / a transparent pressure-sensitive adhesive layer. In particular, when there are three or more layers, the scattering prevention layer 1 / the crack prevention layer 2
In the order of the composition of the crack preventing layer n / the pressure-sensitive adhesive layer, the order of forming each crack preventing layer is the logarithm of the ratio of the shear modulus of the upper and lower layers in contact with each crack preventing layer interface. In the order in which the sum of the absolute values of This is because, when the impact force due to the steel ball falling is relieved in a multilayer structure, the greater the logarithmic value of the ratio of the shear elastic moduli at each interface, the greater the shear stress becomes, and the greater the impact force is, the more the impact force is relieved.

Further, a scattering prevention layer is formed on the front side (front side) of the crack prevention layer, and the shear modulus (G) is 2 × 1.
0 By the above ⁸ Pa, without damage to the shock-absorbing laminate itself, to have a scattering preventing function of the glass, and as cracking preventing layer, the shear modulus (G) is 1 × 10 ⁴ ~2 × 1
By setting the pressure to 0 ⁸ Pa, a function of preventing the glass substrate from cracking was provided.

Further, as the impact relaxation laminate, 51
Impact force 7900 dropped 0g steel ball from 1.5m height
By forming an impact-mitigating laminate on a glass substrate corresponding to reducing the impact force to 50% or less with 0N as 100%, an impact-mitigating laminate having good scattering prevention and not breaking the glass substrate is found. Was.

Further, with respect to the electromagnetic wave shielding property and the near infrared ray shielding property, a conductive metal mesh or a patterned metal mesh is formed on either surface of the transparent laminate of the scattering prevention layer or the crack prevention layer, and a dye that absorbs near infrared rays. Or an electromagnetic wave and near-infrared shielding layer provided with a layer containing
Or a transparent multilayer laminate of a transparent thin film layer / a metal thin film layer, that is, a transparent multilayer thin film obtained by laminating a silver-based transparent conductor film and a high-refractive-index transparent thin film with the transparent shock absorbing laminate, or a metal mesh. Or by complexing a transparent metal layer and a dye that absorbs near-infrared light and a transparent multi-layer laminate or a metal mesh or patterned metal mesh and a transparent thin-film layer that reflects near-infrared light / a metal thin film layer. Visible light transmittance is 40% or more, visible light reflectance is 5% or less, from 800 nm to 120
The near-infrared transmittance in the region of 0 nm can be reduced to 20% or less, that is, a PDP filter that shields electromagnetic waves and / or near-infrared rays with scattering prevention and crack prevention has been completed.

That is, a preferred example of the present invention is a PDP
Forming a transparent shock-mitigating laminate on a glass panel substrate,
And a PDP filter characterized in that the impact force of free fall from a height of 1.5m of a 510g steel ball to 79000N is reduced to 50% or less, and that the scatter prevention and crack prevention, the electromagnetic wave shielding effect and the shielding of near-infrared rays are prevented and the use thereof. The present invention provides a PDP display device.

Hereinafter, a specific configuration of the present invention will be described. FIG. 1 is a schematic cross-sectional view of an impact relaxation laminate according to one embodiment of the present invention. In FIG. 1, the impact relaxation laminate of the present invention comprises a scattering prevention layer 5 / a crack prevention layer 1 / a crack prevention layer 2 / an adhesive layer 3
And used by sticking to the FPD panel glass substrate 4.

Next, FIGS. 2A, B1, B2, and C show specific examples of the impact relaxation laminate of the present invention. Protective layer with anti-reflection (AR) or anti-reflection layer (AG) from above / shatterproof layer /
It has a structure based on a crack preventing layer 1 / a crack preventing layer 2 / an adhesive layer, and is used by being bonded to a PDP glass substrate. The electromagnetic wave shielding layer and / or the near infrared ray shielding layer can be inserted between any layers.

The electromagnetic wave shielding material has an electromagnetic wave shielding effect of 10 dB or more, preferably 20 dB or more.
For example, the radiated electric field intensity from a 42-inch PDP alone is 4
In the case of 0 to 50 dBV / m, an electromagnetic wave shielding material having a shielding effect of 10 dB or more, preferably 20 dB or more is required. That is, the VCCI regulation value (10 m method) especially in the range of 30 to 230 MHz in the range of 30 to 1000 MHz.
In the class A, it is 40 dBμV / m or less. Considering the margin of 6 to 7 dB, the radiated electric field strength of the PDP alone is 4 dB.
It can be seen that the shielding effect is 10 or more, preferably 20 dB with respect to 0-50 dB. The surface resistivity required for a shield effect of 10 dB or more as a relative value is 10Ω.
/ □ or less, preferably 3Ω / □ or less.

As for the NIR shielding property, 800-1200 nm is 2 to prevent malfunction of home appliances and optical communication.
0% or less, preferably 10% or less.

The shielding effect of the electromagnetic wave shielding property of 10 dB or more is exhibited, and the near-infrared ray is 800-1200 nm.
Is not particularly limited as long as it is a material that shields up to 20% or less.

More specifically, when the electromagnetic wave shielding layer is made of a metal mesh and a patterned metal mesh as the electromagnetic wave shielding material and / or the near infrared ray shielding layer, the near infrared ray is shielded from the near infrared ray 800-12000.
In order to reduce the transmittance over a wide range of nm to 20% or less, it is necessary to use a plurality of dyes such as dyes and pigments. Further, apart from this, the near-infrared absorbing dye, a pigment or the like is added to an infrared reflecting material obtained by dispersing conductive fine particles such as ITO and ATO that reflect the infrared region in a thermoplastic, thermosetting, UV or EB curing resin. A composite, a transparent multi-layer laminate composed of a transparent thin film layer / metal thin film layer that reflects near infrared rays and the like are also used.

As another electromagnetic wave shielding material and / or near-infrared shielding layer, n units (2 ≦ n ≦ n) of a transparent thin film layer and a metal layer composed of a silver-based transparent conductor layer as one unit.
5) is a laminated transparent multi-layered thin film, and more specifically, the structure is basically a metal layer / transparent thin film layer or a transparent thin film layer / metal layer / transparent thin film layer or a metal layer / transparent thin film layer / metal layer. And a configuration in which these are repeated two or more times. In other words, in the case of a structure having two transparent thin films with one metal layer, the electromagnetic wave shielding effect is poor, and the near-infrared shielding property does not become 20% or less in a wide range. Even if the shielding effect is satisfied by increasing the thickness of the metal layer, there is a problem that the visible light reflectance increases and the transmittance decreases, and the shielding of near-infrared rays is insufficient.

As such a transparent laminate, any material having optical transparency can be used as the material of the transparent thin film layer. The refractive index of the film may be selected so as to easily achieve desired optical characteristics in the optical design, and the materials and the refractive indexes of the respective layers may be different. A single material or a material obtained by sintering a plurality of materials may be used. Further, a material having a migration preventing effect of the metal thin film layer and a barrier effect of water and oxygen is more preferable. Suitable materials include those from the group consisting of indium oxide, tin oxide, titanium dioxide, cerium oxide, zirconium oxide, zinc oxide, tantalum oxide, niobium pentoxide, silicon dioxide, silicon nitride, aluminum oxide, magnesium fluoride, magnesium oxide. Any thin film composed of one or more selected compounds can be suitably used. In particular, those containing indium oxide as a main component and a small amount of titanium dioxide, tin oxide, or cerium oxide not only have an effect of preventing the deterioration of the metal thin film layer, but also have electrical conductivity, and thus have an electric conductivity between the metal thin film layer and the metal thin film layer. It is particularly preferable from the viewpoint of easy electrical conduction. These transparent thin film layers can be provided by using a vacuum drying process such as a sputtering method, a vacuum evaporation method, or an ion plating method, or a wet method. Is preferred. The thickness of such a transparent thin film layer is preferably in the range of 10 nm to 100 nm.

The metal thin film layer is made of silver alone or an alloy containing silver as a main component, and contains 80% by weight or more of silver, gold, copper,
Palladium, platinum, manganese, composed of one or more elements selected from cadmium,
The material is preferably a solid solution of 99% by weight of silver and 1 to 20% by weight of the above metal. In particular, a solid solution of 1 to 20% by weight of gold in silver is preferable from the viewpoint of prevention of silver deterioration.
For example, when 20% by weight or more of gold is mixed, transparency is easily lost due to coloring, and when 1% by weight or less, silver is easily deteriorated. As a means for forming the silver-based transparent conductor film, a vacuum dry process such as a sputtering method is used. The thickness of the silver-based transparent conductor film is suitably from 1 to 30 nm, more preferably from 5 to 20 nm.

By providing such a transparent multilayer thin film layer consisting essentially of a transparent thin film layer and a silver-based metal layer, an electromagnetic wave shielding effect of 10 dB or more and a near-infrared shielding property, particularly 800 to 1200 n
The transmittance in the m range can be both 20% or less. The visible light transmittance of such a configuration is 40% or more and the near infrared transmittance is 20% or less, preferably 10% or less.

When the transparent multilayer thin film layer is formed on any one of the scattering prevention layer and the crack prevention layer, the metal layer has a thickness of 10 nm which does not decrease the transparency in order to increase the adhesion.
The following may be formed, or the surfaces of the scattering prevention layer and the crack prevention layer may be subjected to a corona treatment, a plasma treatment, and a well-known easy adhesion treatment.

In order not to increase the reflectivity of the filter of the final constitution, a low refractive index layer having a refractive index of 1.50 or less is formed on a scattering prevention layer or a crack prevention layer to form a transparent multilayer thin film layer. It may be formed with an optical thickness of ± 15%.

When the PDP filter of the present invention requires an electromagnetic wave shielding effect, it may be used as a material for the transparent multilayer thin film composed of the above-mentioned metal layer and the transparent thin film layer, or for the electrodes provided on the four sides and side surfaces of the metal mesh and the patterned metal mesh. Is conductive, and corrosion resistance, moisture and heat storage stability is good, there is no particular limitation as long as it has good adhesion to the transparent multilayer thin film, but as specific examples,
Silver paste, alloys composed of one or more metals such as gold, silver, copper, platinum and palladium, and one or more metals such as gold, silver, copper, platinum and palladium applied to organic coating agents Examples thereof include a mixture of a metal alloy and a conductive double-sided tape produced by a method such as applying and impregnating a copper mesh with an adhesive. As a method of forming an electrode, for example, in the case of a conductive double-sided tape, it is directly bonded to four sides of a transparent multilayer thin film, and in the case of a silver paste, various alloy materials, alloy mixed materials, etc., it is formed by screen printing or microgravure coating method. A conventionally known method such as a wet process method, a vacuum deposition method, a dry process method such as a sputtering method, and a plating method can be used. Although the thickness of the electrode is not particularly limited, when it is below the scattering prevention layer as shown in FIGS. 2A to 2C, it is preferable that the thickness is equal to or slightly smaller than the thickness of the crack prevention layer + the transparent pressure-sensitive adhesive layer. When it is above the scattering prevention layer, the thickness of the AR or AG protective layer or A
It is desirable that the thickness be equal to or slightly smaller than the thickness of the R, AG film + adhesive layer.

When the PDP filter does not require the electromagnetic wave effect and only needs to block near infrared rays, it is not necessary to form an electrode.

However, when the function of an electromagnetic wave shielding layer is required as a PDP filter, electrodes are provided on a transparent multilayer laminate composed of a transparent thin film layer / metal thin film layer as an electromagnetic wave shielding layer, and electrically connected to a PDP housing. Need to connect.

For example, when the electromagnetic wave shield layer shown in FIGS. 2A to 2C is on the scattering prevention layer, the AR or AG protective layer needs to be formed other than the electrode portion. When the electromagnetic wave shielding layer is under the scattering prevention layer, it is necessary to form the crack prevention layer or the pressure-sensitive adhesive layer other than the electrode portion.

Incidentally, when the PDP does not need an electromagnetic wave shielding function, the transparent thin film /
Since no electrode is necessary for the transparent multilayer laminate of metal thin films, the location of the formation layer is not particularly limited.

First, as the scattering prevention layer, a plastic film excellent in transparency and excellent in mechanical strength and heat resistance, such as polyethylene naphthalate (PEN) resin, polyethylene terephthalate (P)
Polyester resin such as ET) resin, (meth) acrylic resin, polycarbonate (PC) resin, triacetyl cellulose (TAC), norbornene-based resin, epoxy resin, polyimide resin, polyetherimide resin, polyamide resin, polysulfone, polyphenylene sulfide , Polyethersulfone, etc. are used. This transparent film substrate may be a single layer or a composite layer of two or more layers. The material is not particularly limited as long as the following material properties are satisfied.

In particular, as a mechanical property important for preventing scattering, that is, not breaking (not penetrating) due to falling of a steel ball by an impact force equivalent to 79,000 N, the shear modulus G in dynamic viscoelasticity measurement is 2 × 10 ^8. It must be Pa or more. Below this, when a scattering prevention layer is formed on a PDP panel glass substrate via a transparent adhesive layer, 51
Destruction occurs due to free fall from a height of 1.5 m by a 0 g steel ball, that is, penetration occurs, holes are not formed, scattering prevention is insufficient, and there is a problem of electric shock due to generation of holes. The shear modulus was measured using a dynamic viscoelasticity measuring device DMS120 (manufactured by Seiko Instruments Inc.)
It is a measured value of the shear modulus G at 25 ° C. ± 3 ° C. in Hz. In general, there is a relationship of tensile elastic modulus E = 3G (shear elastic modulus), and the tensile elastic modulus E is about three times the shear elastic modulus G.

Since this scattering prevention layer is constitutively located on the surface side of the PDP, in order to suppress deterioration of the image display of the PDP, a visible light reflectance of 5% or less is preferable as an antireflection layer which is a known technique. May be subjected to a treatment of 3% or less, or may be subjected to an anti-glare treatment with a haze of 5% or less to prevent reflection of external light. As the surface protection function, the surface (pencil) hardness is preferably H or more, and a known hard coat material or the like may be used. The hard coat (HC) layer may be provided on one side or both sides of the scattering prevention layer. The hard coat material to be used may be a UV or EB curing type or a thermosetting type. As the UV curing type, for example, ester type,
Acrylic, urethane, amide, silicone and epoxy monomers and oligomers mixed with a photopolymerization initiator, or acrylic / urethane and acrylic / epoxy monomers start photopolymerization And the like. No polymerization initiator is generally used for EB curing. As the thermosetting type, for example, phenol-based, urea-based, melamine-based, unsaturated polyester-based, polyurethane-based, epoxy-based resins, etc., if necessary, a crosslinking agent, a polymerization initiator, a polymerization accelerator, a solvent, a viscosity adjustment And the like.

Inorganic / organic hybrid resins in which a silicone resin is chemically bonded to an acrylic resin, and the above resins in which inorganic fine particles such as silicon oxide, zirconia, ITO and tin oxide which do not impair the transparency are dispersed. . Note that a leveling agent, an antistatic agent, an ultraviolet absorber, and the like may be added to the HC layer. Basically, it is formed on one or both surfaces under or above the shatterproof layer. To improve adhesion, an additive containing a carboxyl group, phosphate group, hydroxyl group, amino group, isocyanate group, etc. in the HC layer May be used.

The thickness of the HC layer is suitably from 0.1 to 20 μm, and more preferably from 1 to 10 μm.

Further, the AG and AR treated surfaces may be subjected to anti-staining treatment to prevent stains such as adhesion of fingerprints. Note that a film having a function of preventing reflection or reflection may be formed via a transparent pressure-sensitive adhesive layer.

The low refractive index layer of the antireflection layer may be formed by a wet process formed by, for example, a microgravure coating method, or by a dry process such as a vacuum deposition method or a sputtering method. As long as it is excellent in permeability, durability and adhesion, it can be suitably used irrespective of inorganic or organic type, and is not particularly limited. The refractive index is 1.50 or less, and preferably 1.45 or less. Specific examples of the organic material having a low refractive index include a fluorine-containing polymer polymerized using fluoroethylene, vinylidene fluoride, tetrafluoroethylene, or the like as a monomer, a partially or completely fluorinated alkyl ester of (meth) acrylic acid. , Fluorinated silicones, etc., but are not limited thereto. Further, as a specific example of the low refractive index inorganic material, Mg
Examples include, but are not limited to, F ₂ , CaF ₂ , and SiO ₂ . The thickness of the low refractive index layer is preferably 1 μm or less, more preferably 0.5 μm or less.

Further, a contamination prevention layer may be formed on the low refractive index layer. As the material of the stain prevention layer, a cured product composed of an organic polysiloxane-based polymer or a perfluoroalkyl-containing polymer, an alkoxysilane compound having a perfluoroalkyl group, a compound having a silyl group reactive with a perfluoropolyether group, Mono- and disilane compounds containing a polyfluoroalkyl group are exemplified. The thickness of the contamination prevention layer is preferably 0.001 to 0.5 μm,
It is more preferable that the thickness be from 02 to 0.1 μm.

The high-refractive-index layer and the high-refractive-index antiglare layer of the antireflection layer may be formed by a wet process formed by, for example, a microgravure coating method, or by a dry process such as a vacuum evaporation method or a sputtering method. As long as it has excellent visible light transmission, durability and adhesion, it can be suitably used regardless of inorganic or organic type, and is not particularly limited.

The refractive index is 1.5 or more, preferably 1.60 or more. Specific examples of the organic material having a high refractive index include polyfunctional polymerizable compounds containing two or more acryloyl groups and methacryloyl groups such as urethane (meth) acrylate, polyester (meth) acrylate, and polyether (meth) acrylate. Examples thereof include those obtained by polymerization and curing with active energy rays such as ultraviolet rays and electron beams, and those obtained by crosslinking and curing silicone-based, melamine-based, and epoxy-based crosslinkable resin raw materials by heat, but these are also particularly limited. Not something. Specific examples of the inorganic material include a material mainly containing indium oxide and a small amount of titanium dioxide, tin oxide, and cerium oxide.
eF ₃ , Al ₂ O ₃ , MgO, TiO ₂ , ZnO and the like can be mentioned. Further, inorganic fine particles may be dispersed in an organic compound. As the organic compound, the above-mentioned organic materials can be used. As examples of the inorganic fine particles, metal oxide particles such as aluminum, titanium, zirconium, and antimony are preferably used. The thickness of the high refractive index layer is preferably 50 μm or less, more preferably 10 μm or less.

Since the scattering prevention layer is formed on the surface side in the viewing angle direction and is involved in the image characteristics and surface functions of the PDP,
Heat resistance of 80 ° C. or higher is preferred because coating and vacuum thin film formation by known techniques such as surface hardness treatment, low reflection prevention treatment, reflection prevention treatment, electromagnetic wave shielding treatment, antistatic treatment, and contamination prevention treatment are required. .

As shown in FIGS. 2B1 and 2B, when a shield layer and / or a near-infrared shielding layer is formed on the shatterproof layer, an HC layer is provided on the shatterproof layer to form the shield layer or the shatter layer. It may be formed in the order of prevention layer / shield layer / HC layer. Further, when the outermost AR or AG layer is provided on the shield layer, a material containing a phosphate group may be added to the AR or AG material in order to improve the adhesion.

Next, as the crack prevention layer, the transmittance is 60%.
% Or more, and the shear modulus G by dynamic viscoelasticity is preferably in the range of 1 × 10 ⁴ Pa to 2 × 10 ⁸ Pa.

That is, if the shear modulus is less than 1 × 10 ⁴ Pa, it is too soft to be easily processed at the time of punching or cutting such as sheeting, and there is a problem that the edge portion protrudes.

On the other hand, when it exceeds 2 × 10 ⁸ Pa,
There is no ability to reduce the impact force of N, and the glass substrate of PDP is broken. In addition, the thickness which does not crack becomes as thick as 2 mm or more only by the impact relaxation layer, and there is a problem of image deterioration.

The material of the crack preventing layer is not particularly limited as long as it falls within the above-mentioned characteristic range.

Examples of such a transparent crack-preventing layer include an ionomer resin obtained by crosslinking the molecules of an ethylene-methacrylic acid copolymer with metal ions (Na ⁺ , Zn ^2+, etc.), EVA (ethylene-vinyl acetate polymer), and PVC. , EE
A (ethylene acrylate copolymer), PE, PP, thermoplastic resin such as polyamide resin, polybutyral resin, polystyrene resin, and polystyrene, polyolefin, polydiene, vinyl chloride, polyurethane, polyester, polyamide, fluorine, Chlorinated polyethylene, polystyrene / polyolefin copolymer,
(Hydrogenated) Thermoplastic elastomer exhibiting rubber elasticity such as polystyrene / butadiene copolymer, polystyrene / vinyl polyisoprene copolymer, or polyethylene,
A blend of a thermoplastic elastomer with a polyolefin such as polypropylene can also be used.

Further, polyolefin (PP or PE)
Etc.) / Thermoplastic resin (EVA) / polyolefin, polyolefin (PP or PE) / polyolefin + thermoplastic elastomer / polyolefin (PP or PE) laminate or multi-layer system with different blend ratio of polyolefin + thermoplastic elastomer And PP / polyolefin blended thermoplastic elastomer, PP /
PE / PP and the like can also be used.

Further, a core / shell type resin having a thermoplastic elastomer core and an acrylic resin shell structure can also be used.

Further, a transparent pressure-sensitive adhesive layer can be used as a crack preventing layer. For example, there are acrylic type, rubber type and polyester type, and it is particularly preferable to use an acrylic pressure-sensitive adhesive layer having high transparency. The acrylic pressure-sensitive adhesive layer is an acrylic polymer, that is, as a main monomer for mainly imparting appropriate wettability and flexibility to the pressure-sensitive adhesive layer, the glass point transfer (Tg) of the polymer is 60 ° C. or less. One or more alkyl (meth) acrylates and, if necessary, a functional group-containing monomer and another copolymerizable monomer, using an appropriate polymerization catalyst, by a solution polymerization method, An acrylic copolymer obtained by polymerization by a method such as an emulsion polymerization method, a bulk polymerization method (in particular, a polymerization method using ultraviolet irradiation), or a suspension polymerization method was used, and various known additives were appropriately added thereto. Things are used. A thermal crosslinking type, a light (ultraviolet ray, electron beam) crosslinking type, or the like may be used.

As adhesive components other than the above-mentioned adhesive, natural polymer glue, starch, semi-synthetic polymer cellulose acetate, synthetic polymer polyvinyl acetate, polyvinyl chloride, epoxy resin, urethane resin, Polychloroprene, acrylonitrile-butadiene copolymer (NB
R), melamine resin, acrylic resin, ethylene-vinyl acetate copolymer, polyester resin, polyamide resin and the like. These can also be used as adhesives of various curing types such as room temperature curing, heat curing, ultraviolet ray, electron beam, and laser irradiation curing types.

The crack-preventing layer can be formed by directly bonding one surface of the scattering-preventing layer by heat lamination or the like, or by coating a dissolved resin. Direct heat lamination and application of dissolved resin are also possible. If the adhesion is insufficient, the adhesion can be improved by adding various adhesion-imparting agents or by surface treatment (corona treatment, plasma treatment, etc.) of the crack prevention layer or the scattering prevention layer. When the pressure-sensitive adhesive layer and the adhesive component are crack-preventing layers, the scattering-preventing layer and the crack-preventing layer may be bonded to each other by coating the scattering-preventing layer as a known technique, or by coating a separate peelable film. The formed product may be transferred and bonded.

Next, as the transparent pressure-sensitive adhesive layer which is directly in contact with the PDP panel, there are acrylic type, rubber type and polyester type, and it is particularly preferable to use a highly transparent acrylic type pressure-sensitive adhesive layer. The acrylic pressure-sensitive adhesive layer is an acrylic polymer, that is, as a main monomer for mainly imparting appropriate wettability and flexibility to the pressure-sensitive adhesive layer, the glass point transfer (Tg) of the polymer is 60 ° C. or less. One or two or more alkyl (meth) acrylates,
If necessary, the functional group-containing monomer and other copolymerizable monomer may be mixed with a suitable polymerization catalyst to form a solution polymerization method, an emulsion polymerization method, a bulk polymerization method (particularly, a polymerization method using ultraviolet irradiation), a suspension method, or the like. An acrylic copolymer obtained by polymerization by a polymerization method or the like is used, and a mixture containing various known additives as appropriate is used. A thermal crosslinking type, a light (ultraviolet ray, electron beam) crosslinking type, or the like may be used.

Since the transparent pressure-sensitive adhesive layer is directly bonded to a PDP glass substrate, it must have both pressure-sensitive adhesive strength and reworkability, and the shear modulus is 1 × 10 ⁴ P
a to 1 × 10 ⁷ Pa is preferable. Further, the thickness of the pressure-sensitive adhesive layer is from 10 μm to 500 μm in view of the adhesive property and the reworkability.
μm is good. If it is too thin, the adhesive properties will not be satisfactory, and if it is too thick, there will be problems such as glue sticking out of the edge portion when forming the sheet.

The thickness of the scattering prevention layer is preferably in the range of 10 μm to 600 μm from the viewpoint of preventing damage. 10 μm
In the following, there is a problem to be damaged by the impact force of 79000N, 600μ
If it is more than m, the thicknesses of the crack prevention layer and the pressure-sensitive adhesive layer become too thin, and the crack prevention properties cannot be satisfied.

The crack prevention thickness is 20 μm to 170 μm.
0 μm is good, and preferably 20 to 1000 μm. If the thickness is thin, the crack-preventing property is reduced. On the other hand, if the thickness is large, the price is increased and the transparency is reduced.

The total thickness of the above-described scattering prevention layer + one or more crack prevention layers + the transparent pressure-sensitive adhesive layer + the electromagnetic wave shielding layer and / or the near-infrared shielding layer is preferably 5 mm or less from the viewpoint of deterioration of the image quality of the PDP. Desirably, it is 3 mm or less. Further, the light transmittance of the PDP filter is required to be 40% or more, and preferably 50% or more, from the viewpoint of preventing a decrease in contrast and image quality.

When a color adjustment of an image is required as a PDP filter, a dye having a known absorption in the visible light region,
A pigment or the like may be added.

Next, about the impact force measurement by the free fall of the steel ball, a normal temperature (23 ± 3 ° C.) when a steel ball of about 510 g having a diameter of 50 mm was dropped from a height of 1.5 m using an apparatus (FIG. 3).
The impact force F0 (N) at was measured. The impact force F0 is
As shown by the impact force at a falling ball height of 1.5 m on the horizontal axis in FIG. 4, it was about 79000 N.

On the force sensor of the impact force measuring device shown in FIG. 3, one or more crack prevention layers and a scattering prevention layer were formed via an adhesive layer, and a steel ball having a diameter of 50 mm and a weight of about 510 g was added to each of the steel balls. Drop from the height of 5m to the center of the shock absorbing laminate,
The impact force F1 <N> at that time was measured to determine how much the impact force was reduced.

As the impact relaxation rate, the impact relaxation rate R
1 (%) = [F1 / F0 (79000N)] × 100

Next, as a glass substrate for a plasma display (PDP), which is considered to be particularly vulnerable to impact among the FPD panels, a high strain point glass (PD200, elastic modulus 7.
6 × 10 ¹⁰ Pa) and select 2.8mm thick 30cm ×
A glass substrate having a size of 30 cm was used as a test glass substrate.

As for the crack test of the glass substrate, an AL plate (300 × 300 mm, t = 2 mm) was used as a crack test configuration shown in FIG.
A glass substrate PD200 (t = 2.8mm, 300mm × 300m)
m) Place one or two sheets, and process the window frame up and down A
A glass plate was cracked by dropping about 510 g of steel balls from a height of 1.5 m at the center of the glass substrate and fixing the four sides with an L plate (plate having a thickness of 2 mm). Table 1 shows the results.

[0076]

[Table 1]

From the glass substrate cracking test shown in Table 1, when the impact force at which the glass plate is broken is set at a constant steel ball weight of 510 g ± 20 g, the glass substrate is broken at 60 cm or more, that is, at an impact force of about 36000 N or more in a single glass structure. . Then, in the case of a two glass substrate structure, the glass substrate is broken at a height of 30 cm or more, that is, an impact force of 21000 N or more. In order to design the glass plate so as not to break, when the above-mentioned shock-mitigating laminate is formed on a glass substrate, the shock force that does not break is 510 g.
When the weight of the steel ball is fixed, it is preferably 36000 N or less, preferably 21000 N or less. In other words, the shock relaxation rate R0 (%) at which the glass substrate does not crack is about 50% at 36000N / 79,000N × 100 from Table 1.
Less than or equal to 27% (21000/79000 × 100)
It is understood that the following design is sufficient.

Regarding the above steel ball drop test, UL 1418
(Approx. 540g x 1.3m height pendulum drop), UL1930 (approx. 50
0g x 1.3m height pendulum drop), Electricity Control Law (500g
X1.5m) and other safety standards, the evaluation of the anti-scattering property after a steel ball drop test specifies the number, size, and distance of fragments, and finger-sized holes are not opened because there is no electric shock (penetration) However, there is a problem if the expensive FPD panel is actually broken.

Therefore, the actual height of a 510 g steel ball is 1.5 m.
Measure the impact force at which the glass substrate is broken by falling from
In addition, by designing a structure that does not crack due to the formation of the shock-mitigating laminate, the design of the shock-mitigating laminate that does not crack the panel in addition to the prevention of scattering and the safety (no electric shock) has been clarified.

That is, an impact-relaxing laminate having an impact-mitigating force equivalent to reducing the impact force of 75,000 N dropped from a steel ball having a height of 1.5 m and about 500 g in the present invention to 50% or less, preferably 27% or less. By structuring the body, it was clarified that the glass substrate did not break. (1) Design of a shock-mitigating laminate that does not break the glass substrate (a) F2 (glass-breaking impact force)> F1 (N) (impact force by the shock-releasing laminate) (b) R0 (glass-breaking impact relaxation rate)> R1 (%) (Impact relaxation rate by impact relaxation laminate) (2) Glass substrate cracking test due to steel ball falling Glass substrate (high strain point glass: PD200 manufactured by Asahi Glass Co., Ltd., size (300 mm × 300 m) as shown in FIG.
m, t = 2.8 mm) A shock-absorbing laminate (scatter prevention layer + crack prevention layer + adhesive layer) is formed on top of this, and 500 g of steel balls are dropped from a height of 1.5 m to the center to prevent scattering. The properties (prevention of breakage) and the cracking of the glass substrate were visually evaluated.

The impact relaxation force F1 (N) was measured by forming an impact relaxation laminate on a force sensor as described above and using an FFT analyzer (see FIG. 3).

The impact force F0 of the steel ball itself due to the fall
With respect to (N), the impact force F2 (N) actually cracked in the glass cracking test in FIG. 5 and the impact relaxation force F1 due to the formation of the transparent relaxation laminate were determined as glass fracture prevention relaxation rates R0 and R1, respectively.

R0 (%) = (F2 / F0) × 100, R1 (%) = (F1 /
F ₀ ) × 100 R 0> R 1 means that the glass substrate is not broken.

Next, with regard to the laminated structure of the transparent shock absorbing laminated body, in order to prevent scattering (falling of holes) due to falling of steel balls, in order to prevent breakage (occurrence of holes), scattering is prevented on the surface side of the PDP glass substrate. It is desirable to form a layer.
The composition is a scattering prevention layer, a crack prevention layer, and an adhesive layer.
If the crack prevention layer is on the scattering prevention layer, the crack prevention layer will be damaged. Therefore, it is preferable that the crack prevention layer is formed below the scattering prevention layer from the viewpoint of prevention of scattering. However, when looking at the entire filter, holes can be prevented by the scattering prevention layer, so that a crack prevention layer may be formed thereon. In addition, at least one layer of the scattering prevention layer is formed on the surface side, and alternatively, it may be formed between the crack prevention layer and the pressure-sensitive adhesive layer on the glass substrate.
That is, a configuration of a scattering prevention layer / a crack prevention layer / a scattering prevention layer may be employed.

Further, when the above-mentioned impact relaxation laminate is composed of an adhesive layer / two or more types of anti-cracking layers / an anti-scattering layer, the upper and lower layers in contact with each interface of the anti-scattering layer, each anti-cracking layer and the adhesive layer. It is preferable that the order of lamination is such that the sum of the absolute values of the logarithms of the ratios of the shear modulus of the materials is the largest.

That is, in the configuration shown below, in order to alleviate the impact force equivalent to 79000 N due to the steel ball drop, the configuration in which the total sum of the absolute values of the logarithms of the ratios of the shear elastic moduli shown in FIG. There is a tendency that the stress is large and the resilience of the impact force due to the steel ball falling is also increased. Anti-scattering layer 1 / anti-cracking layer 2, anti-cracking layer 3 ... anti-cracking layer n / adhesive layer Sum of absolute values of logarithm of shear modulus ratio: | Log G1 / G2 | + | Log G2 / G3 | +.・ ・ ・ + ｜ Log Gn-1 / Gn ｜ +
| Log Gn / G pressure-sensitive adhesive layer | For example, the scattering prevention layer 1, the crack prevention layer 2, and the crack prevention layer 3
And the pressure-sensitive adhesive layer 4, the anti-scattering layer 1 (thickness: 188 μm, shear modulus:
1.4 × 10 ⁹ Pa) / crack prevention layer 2 (thickness: 25 μm,
Shear modulus: 7.7 × 10 ⁴ Pa) / Crack prevention layer 3 (thickness: 400 μm, shear modulus: 6.9 × 10 ⁷ Pa)
/ Adhesive layer 4 (thickness: 25 μm, shear modulus: 7.7 ×
10 ⁴ Pa) In response to an impact force of 79000 N with a steel ball falling of 510 g × 1.5 m, the impact relaxation rate R1 was determined by the impact force measurement shown in FIG.
(%) = [(Impact force due to the formation of the laminate) / impact force without the laminate] × 100, and when the order of lamination of the crack prevention layer is selected, R1 (%) is 1 / 2/3/4 <1/3/2 /
4, the former configuration has a larger total sum of the absolute values of the logarithms of the shear modulus ratios of the upper and lower layers in contact with the interface, and
It means that the relaxation of the impact force to 0N is large.

Table 2 shows the results of the specific examples.

[0088]

[Table 2]

Anti-scattering layer 1 (1.4 × 10 ⁹ Pa) / anti-cracking layer 2 (7.7 × 10 ⁴ Pa) / anti-cracking layer 3 (6.9)
× 10 ⁷ Pa) / pressure-sensitive adhesive layer 4 (7.7 × 10 ⁴ Pa), the scattering prevention layer is arranged first, and the order of the crack prevention layers 2 and 3 and the pressure-sensitive adhesive layer is changed. The figure shows the impact relaxation rate when a 510 g steel ball was dropped from a height of 1.5 m onto the center of a force sensor.

That is, from Table 2, No. 1 in which the total sum of the absolute values of the logarithms of the shear modulus ratios at each interface of the crack prevention layer is large,
The impact relaxation rate is the smallest at 24%, that is, the impact relaxation is large, which means that the FPD glass substrate is hardly broken even with one or two glass substrates.

Therefore, as for the structure of the crack prevention layer, it is preferable in terms of prevention of glass breakage that the total sum of the absolute values of the logarithms of the shear elastic modulus ratios at the respective interfaces is large because the relaxation of the shear stress reduces the impact relaxation rate.

[0092]

EXAMPLES The present invention will be described more specifically with reference to the following examples. (1) Design of an impact-mitigating laminate in which the glass substrate is not broken Glass impact strength (F2) ≧ impact by the impact-mitigating laminate
(F1) <N> Glass crack impact relaxation rate (R0) ≧ impact relaxation rate by impact relaxation laminate (R1) <%> (2) Falling ball impact test using steel balls A glass substrate (high strain point Glass: PD200 manufactured by Asahi Glass Company, size (300 mm x 300 m
(m, t = 2.8 mm) to form an impact-mitigating laminate (scattering prevention layer + anti-cracking layer + adhesive layer), drop about 510 g of steel balls from the height of 1.5 m to the center, and scatter The prevention (breakage prevention) and the cracking of the glass substrate were visually evaluated.

The impact relaxation force F1 (N) was measured by forming an impact relaxation laminate on a force sensor as described above and using an FFT analyzer (see FIG. 3). In addition, the impact force F2 (N) actually broken in the glass cracking test of FIG. 5 and the impact relaxation force F1 due to the formation of the transparent relaxation laminated body are respectively prevented from glass fracture against the impact force F0 (N) of the steel ball itself. The relaxation rates were obtained as R0 and R1.

R0 (%) = (F2 / F0) × 100, R1 (%) = (F1 / F
0) × 100 R0> R1 means that the glass substrate is not broken. (3) Measurement of shear modulus by dynamic viscoelasticity device Dynamic viscoelasticity device DMS manufactured by Seiko Instruments Inc.
120, using a fixed condition of a frequency of 1 Hz by temperature dispersion, a sample of 5 mm × 10 mm size was obtained at 25 ° C.
The shear modulus G at ± 3 ° C. was measured. (4) Transmittance and reflectance of visible light The transmittance and reflectance of visible light were obtained by measuring the 0 ° incident transmission and reflection spectrum with an instantaneous multiphotometer MCPD-3000 manufactured by Otsuka Electronics Co., Ltd. The visible light transmittance and the visible light reflectance were calculated from the spectrum according to JIS R-3016. The near-infrared cut ratio was measured using Hitachi Ltd. U-3410 (spectrophotometer), and the cut ratio at a wavelength of 800 to 1200 nm was measured.

(Example 1) As a film for preventing scattering,
Polyethylene terephthalate (PET) (OX69K manufactured by Mitsubishi Chemical Corporation, thickness 175 μm, G 1.4 × 10 ⁹ P
a) An acrylic pressure-sensitive adhesive layer (G 7.7 ×) having a weight average molecular weight of about 1.5 million and a Tg of about −20 ° C., made of a copolymer of butyl acrylate and acrylic acid, was used as a crack preventing layer 1 for the film. 10 ⁴ Pa) to form a thickness of 25 μm,
Next, PP / EVA / PP (POVIC-T, 400 μm, G 6.9 × 10 ⁷ manufactured by Achilles) was used as the crack prevention layer 2.
Pa) The laminated film was laminated. Next, the acrylic pressure-sensitive adhesive was formed on the surface of the laminated film so as to have a thickness of 25 μm. The thus-prepared impact relaxation laminate was applied to a high strain point glass substrate (PD200, 2.8 m thick).
m, 300 × 300 mm) via the above-mentioned pressure-sensitive adhesive layer.

Next, the glass plate cracking test configuration shown in FIG.
A steel ball drop test was performed on a single piece type. As a steel ball drop condition, 510 g having a diameter of 50 mm was used and dropped from a height of 1.5 m to the center of the glass substrate.

The impact mitigation force due to the steel ball falling in the pressure-sensitive adhesive layer / crack preventing layer 2 / crack preventing layer 1 / scattering preventing layer configuration was measured by using the force sensor device shown in FIG. Was measured, and the relaxation rate was determined.

The transmittance of the glass substrate provided with the shock absorbing laminate is 82%. In addition, the total thickness of the shock absorbing laminate is 6
It was 25 μm. With this thickness, even when directly attached to the FPD panel, deterioration of image quality by visual observation was not recognized.

(Example 2) P of the crack preventing layer 2 of Example 1
Example 1 was followed except that the P / EVA / PP (POVIC-T manufactured by Achilles) laminated film was 600 μm.

The transmittance of the glass substrate provided with the shock absorbing laminate was 80%, and the total thickness was 825 μm. Structure: PET / pressure-sensitive adhesive layer / POVIC-T / pressure-sensitive adhesive layer.

(Example 3) The procedure was the same as that of Example 1 except that a film of polyurethane 500 µm (DUS605, non-yellowing type, G 4.6 x 10 ⁷ Pa) made of polyurethane was used as the crack preventing layer 2.

The transmittance of the glass substrate provided with the shock absorbing laminate was 78%, and the total thickness was 625 μm. Structure: PET / pressure-sensitive adhesive layer / urethane / pressure-sensitive adhesive layer.

(Example 4) [0103] Except that the film was made a cleartech H 400 µm (a styrene-vinyl-isoprene elastomer was added to polypropylene manufactured by Kuraray Trading Co., Ltd., G 3.1 x 10 ⁷ Pa) as the crack-preventing layer 2, and the film was formed. According to Example 1. The transmittance of the glass substrate provided with the impact relaxation laminate was 72%, and the total thickness was 625 μm. Configuration: PET / pressure-sensitive adhesive layer / Cleartech H / pressure-sensitive adhesive layer.

(Example 5) As a crack preventing layer 2, soft vinyl chloride (Vinirus manufactured by Achilles, 600 μm, G1.4)
× 10 ⁷ Pa) Example 1 was followed except that a film was used.

The transmittance of the glass substrate provided with the shock absorbing laminate was 81%, and the total thickness was 825 μm. Structure: PET / pressure-sensitive adhesive layer / soft PVC / pressure-sensitive adhesive layer.

Example 6 Example 2 was followed except that crack prevention 1 and 2 in Example 2 were reversed. Composition: PE
T-adhesive layer / POVIC-T / adhesive layer.

(Comparative Example 1) The crack preventing layer 2 of Example 1 was replaced with P
Example 1 was repeated except that the ET was changed to 400 μm. Structure: PET / pressure-sensitive adhesive layer / PET (400) / pressure-sensitive adhesive layer (Comparative Example 2) The same procedure as in Example 1 was carried out except that the crack prevention layers 1 and 2 of Example 1 were removed. Configuration: PET / adhesive layer.

(Comparative Example 3) Except that the urethane film and the adhesive layer were directly bonded to the high strain point glass (PD200) except for the shatterproof PET film of Example 3 and the adhesive layer of the crack prevention layer 1, except that According to Example 3.

The above results are shown in Tables 3 and 4.

[0110]

[Table 3]

[0111]

[Table 4]

As is evident from the above embodiment, 510
g The impact force of a steel ball dropped from a height of 1.5 m is 7900.
By forming two or more types of crack-preventing layers (one or more types) having different shear elastic moduli and one or more anti-scattering layers in order through a transparent pressure-sensitive adhesive layer on a PDP glass panel substrate that is broken by 0N, 50% or less of impact force, preferably 25%
It is possible to realize a shock-relaxed laminate which is relaxed below and has both scattering prevention and crack prevention.

As for the composition of the anti-scattering layer and the two or more types of anti-cracking layers, when the same material and the same thickness are compared, the anti-scattering layer on the outermost surface and the pressure-sensitive adhesive layer immediately above the glass plate are indispensable. In the configuration, the greater the absolute value of the logarithmic value of the ratio of the shear modulus of the upper and lower layer materials in contact with each interface, the more the impact force can be reduced.

Further, since the above-mentioned laminate is formed directly on the glass substrate, there is no gap and double reflection of external light and accumulation of dirt are eliminated. Further, the transmittance of the impact relaxation laminate of the present invention is 60%.
% Or more, preferably 70%, and the total thickness is 1 mm
An object of the present invention is to provide an impact relaxation laminate which does not impair the image characteristics of the FPD panel, and a flat panel display including the same, particularly a plasma display.

(Example 7) Polyethylene terephthalate PET (A4100 manufactured by Toyobo Co., Ltd., single-sided easy-adhesion treatment thickness: 188 μm, G1.4 × 10 ⁹ Pa) as a scattering prevention layer was cured by ultraviolet rays with a refractive index of 1.65. Acrylic urethane-based resin is diluted with methyl isobutyl ketone to a predetermined concentration, coated with a wire bar, dried at 60 ° C, and then cured with an ultra-high pressure mercury lamp at an irradiation of 400 mJ / cm ² of ultraviolet light. As a result, a hard cord layer having a thickness of 5 μm was formed after drying.

Next, an alkoxysilane-based sol having a refractive index of 1.36 was applied on the HC layer with a wire bar.
After curing at 120 ° C. for 10 minutes, a low-refractive-index layer having a thickness of 0.1 μm was formed to form an antireflection layer.

Next, a film of SiO ₂ (95 nm) was formed at room temperature by a vacuum evaporation method on the surface of the anti-scattering layer opposite to the formation of the anti-reflection layer. Next, a transparent multilayer thin film was formed by a technique of forming a thin film by repeating the order of a high-refractive thin film, a silver-based transparent conductive film, and a high-refractive-index dielectric film by DC magnetron sputtering. In ₂ O ₃ -12.6 wt% TiO ₂ is used as a target material for forming a high refractive index dielectric film, and Ag-5 wt% Au is used for a target material for forming a silver-based transparent conductor film. It was used.

The film thickness was measured by a calibration curve of the film formation rate by a surface roughness meter (DEKTAK3) of the film attached to the thick film, and a precise measurement by a transmission electron microscope.

AR / HC / PET / SiO ₂ (95) /IT32.5/Ag13/IT65/Ag13/IT65/Ag
13 / IT32.5 (nm) The thus-obtained anti-scattering laminated film with an anti-reflection protective layer has a surface resistance of 1.6 Ω / □ and a transmittance of 70.
%Met.

Next, as an anti-cracking layer 1, an acrylic pressure-sensitive adhesive layer (G 7.7) composed of a copolymer of butyl acrylate and acrylic acid and having a weight average molecular weight of about 1.5 million and a Tg of about -20 ° C. × 10 ⁴ Pa) with a thickness of 25 μm, and then as a crack prevention layer 2 PP / EVA / PP (POVIC-T, 400 μm, G 6.9 × by Achilles)
10 ⁷ Pa) The laminated film was laminated. Then, the acrylic pressure-sensitive adhesive was applied to the surface of the laminated film with a thickness of 25 μm.
It formed so that it might become.

The above pressure-sensitive adhesive layer / POVIC / pressure-sensitive adhesive layer laminate was bonded to the surface of the transparent laminate composed of the Ag / IT laminate of the scattering prevention layer.
The DP filter is connected to a high strain point glass substrate (PD200, 1
(Thickness: 2.8 mm, 300 × 300 mm).

Then, using the PDP glass substrate cracking test configuration shown in FIG. 5, a steel ball drop test was performed on one and two glass substrates with a PDP filter.
Using 510 g of diameter 50 mm as steel ball drop condition,
The glass substrate was dropped from a height of 1.5 m to the center of the glass substrate.

Incidentally, the above-mentioned pressure-sensitive adhesive layer / crack prevention layer 2 / break prevention layer 1 / electromagnetic wave shield + NIR shield / scattering prevention layer / H
Fig. 3 shows the impact mitigation force due to the steel ball falling in the C / AR configuration.
Measure the impact force using the force sensor device shown in
The relaxation rate was determined.

The transmittance of this glass substrate with a filter for PDP was 63%. Further, the total thickness of the impact relaxation laminate including the pressure-sensitive adhesive layer was about 643 μm. With this thickness, even when directly attached to the PDP panel, deterioration of image quality by visual observation was not recognized.

Structure: AR / HC layer / scattering prevention layer PET /
SiO ₂ / (IT / Ag) 3 / IT / anti-cracking layer 1 adhesive layer / anti-cracking layer 2 POVIC-T / adhesive layer / PDP glass substrate Here, (IT / Ag) 3 means IT / Ag layer This means that there are three layers as described above. The same applies hereinafter.

FIG. 6 is a schematic cross-sectional configuration explanatory diagram in which the thus obtained transparent impact relaxation laminate of the present invention is bonded to a glass substrate.

Example 8 The HC layer of Example 1 was provided on the transparent shatterproof layer of Example 7. In addition, SiO
₂ (λ / 4n, 95 nm), a metal layer / a transparent thin film layer is further formed, and SiO ₂ (λ / 2n, 19
0 nm), and a perfluoroalkylsilane-based material (KP801M, manufactured by Shin-Etsu Chemical Co., Ltd.) as a pollution inhibitor.
Was applied to form a contamination preventing layer having a thickness of 0.01 μm.

The transmittance of the glass substrate with a filter for PDP was 65%, and the total thickness was about 638 μm. Configuration: anti-fouling layer processing _{SiO 2 / (IT / Ag)} 3 / IT / SiO
₂ / HC layer / scattering prevention layer PET / cracking prevention layer 1 adhesive layer / cracking prevention layer 2 / POVIC-T / adhesive layer / PDP
Glass Substrate FIG. 7 is a schematic cross-sectional configuration explanatory view in which the thus obtained transparent shock absorbing laminate of the present invention is bonded to a glass substrate.
Shown in

Example 9 SiO ₂ treated with an anti-staining layer of Example 8
Instead of the protective layer, a commercially available ARPET (Realok, manufactured by NOF CORPORATION, about 105 μm) film was laminated on the electromagnetic wave shield + NIR shielding layer via the transparent adhesive layer (25 μm) described in Example 7 to remove the HC layer. Except for this, the procedure was the same as in Example 8.

The transmittance of this glass substrate with a filter for PDP was 63%, and the total thickness was about 768 μm. Composition: Anti-reflection PET / Adhesive layer / (IT / Ag) 3 / IT / Si
O ₂ / scattering prevention layer PET / breaking prevention layer 1 pressure-sensitive adhesive layer / breaking prevention layer 2POVIC-T / pressure-sensitive adhesive layer / PDP glass substrate The thus obtained transparent shock-releasing laminate of the present invention is attached to a glass substrate. FIG. 8 is an explanatory diagram of the combined schematic cross-sectional configuration.
Shown in

Example 10 The procedure of Example 7 was followed except that a film of urethane 500 μm (DUS605, non-yellowing type, G 4.6 × 10 ⁷ Pa, manufactured by Seedam Company) was used as the crack preventing layer 2.

The transmittance of the glass substrate with a filter for PDP was 65%, and the total thickness was 643 μm. Configuration: AR / HC / shatterproof layer _{PET / SiO 2 / (IT /} A
g) 3 / IT / anti-cracking layer 1 adhesive layer / anti-cracking layer 2 DUS 60
5 / Adhesive layer / PDP glass substrate (Example 11) As a crack prevention layer 2, Cleartec H4
00μm (Kuraray Trading polypropylene with styrene / vinyl / isoprene elastomer added, G
3.1 × 10 ⁷ Pa) According to Example 7, except that the film was used.

The transmittance of the glass substrate with a filter for PDP was 58%, and the total thickness was 643 μm. Structure: AR / HC / scattering prevention layer PET / SiO ₂ / (IT /
Ag) 3 / IT / anti-cracking layer 1 adhesive layer / anti-cracking layer 2 Cleartech H / adhesive layer / PDP glass substrate (Example 12) The anti-cracking layers 1 and 2 of Example 7 were reversed. Except for the above, it was the same as Example 7. Structure: AR / HC / scattering prevention layer PET / SiO ₂ / (IT /
Ag) 3 / IT / anti-cracking layer 1 POVIC-T / anti-cracking layer 2 adhesive layer / adhesive layer / PDP glass substrate (Comparative Example 4) The anti-cracking layer 2 of Example 7 was replaced with PET400.
Example 1 was repeated except that μm was used. Structure: AR / HC / scattering prevention layer PET / SiO ₂ / (IT /
Ag) 3 / IT / anti-cracking layer 1 adhesive layer / anti-cracking layer 2PE
T / adhesive layer / PDP glass substrate The transmittance of this glass substrate with a filter for PDP is 63
%, And the total thickness was 643 μm.

(Comparative Example 5) The crack preventing layers 1 and 2 of Example 7
Example 7 was repeated except that was removed. Structure: AR / HC / scattering prevention layer PET / SiO ₂ / (IT /
Ag) 3 / IT / adhesive layer / PDP glass substrate The transmittance of this glass substrate with a filter for PDP is 65
%, And the total thickness was 218 μm.

(Comparative Example 6) The scattering prevention PET of Example 10
Example 7 was repeated except that the urethane film and the pressure-sensitive adhesive layer were directly bonded to the high strain point glass (PD200) except for the film and the pressure-sensitive adhesive layer of the crack prevention layer 1. Structure: AR / HC / SiO ₂ / (IT / Ag) 3 / IT / breakage prevention layer 2DUS 605 / adhesive layer / PDP glass substrate The transmittance of this glass substrate with a filter for PDP is 65.
%, And the total thickness was 430 μm.

(Comparative Example 7) The metal layer / transparent thin film layer was IT65 / A
Example 7 was followed except that it had a three-layer structure of g13 / IT65 (nm). The transmittance of this glass substrate with a filter for PDP was 66%, and the total thickness was 643 μm.
The surface resistance of the shield layer was 5.5Ω / cm ² .

[0137] (Example 13) of Example 9, the anti-reflection PET / adhesive layer / the exception of (IT / Ag) 3 / IT / SiO 2 of SiO ₂ / shatterproof PET, shatterproof conductive thin film stack A conductive patterning mesh made of Cu and Cr was formed on the reverse side of the PET and formed on the reverse side with a wire diameter of 30 μm and a line pitch of 200 μm. The aperture ratio of the patterning mesh is about 74%. Further, an adhesive layer is formed thereon to fill the opening, and the antireflection PET is further placed thereon.
Example 9 is adhered except that is bonded.

The structure is as follows: ARPET / adhesive layer / patterned mesh Cu-Cr / PET / (IT / Ag) 3+
IT / break prevention 1 adhesive layer / break prevention 2POVIC-T
/ Pressure-sensitive adhesive layer / PDP glass substrate. The transmittance was about 50% and the reflectance was about 2%.

FIG. 9 is a schematic cross-sectional configuration explanatory view in which the thus obtained transparent impact relaxation laminate of the present invention is bonded to a glass substrate. In FIG. 9, 10 indicates a silver paste, 11 indicates an adhesive layer, and 12 indicates a conductive patterning mesh.

In this configuration, the electromagnetic wave shielding layer is a patterning mesh layer and a conductive thin film laminate, and the near-infrared shielding layer is a conductive thin film laminate.

In the above Examples 7-13, a silver paste (Dotite FA-301C manufactured by Fujikura Kasei Co., Ltd.) was applied on the transparent conductive film laminate and the metal patterning mesh to ground the electromagnetic wave shielding layer.
A) is printed on a screen printer to form a four-sided frame print having a width of about 10 mm and a thickness of about 20 μm. That is, when a protective layer is provided on the shield surface, the protective layer is formed inside the silver paste other than the four-sided frame, and when the shield surface is the back surface of the scattering prevention PET, the crack prevention layer 1, the crack prevention layer 2,. An adhesive layer is formed inside the silver paste other than the four-sided frame.

The above results are shown in Tables 5 and 6.

[0143]

[Table 5]

[0144]

[Table 6]

As is evident from the above results, the embodiment of the present invention provides a shock-relaxed laminate having both high impact relaxation rate, scattering prevention property and crack prevention property, excellent optical properties and high light transmittance. I realized it. Furthermore, since the above-mentioned laminate is formed directly on the glass substrate, there is no void, and double reflection of external light and accumulation of dirt are eliminated. Further, by forming the electromagnetic wave shielding layer and the near infrared (NIR) shielding layer into a multilayer structure of a silver-based transparent layer / a highly bent thin film layer, the shielding effect can be reduced to 10 dB or more and the transmittance in the NIR 800 to 1200 nm region can be reduced to 20% or less. And was useful as a PDP filter.

[0146]

According to the present invention, a glass panel is directly laminated with a transparent shock-absorbing layer composed of a scattering-preventing layer, a crack-preventing layer, and an adhesive layer to prevent the glass from scattering and breaking. And directly adheres to the glass panel itself to improve the clarity of the image. Furthermore, there is no air layer between the panel and the shock absorbing sheet, there is no double reflection of external light, and dirt such as dust and dirt is deposited. It is possible to provide a shock-absorbing laminate for FPD that does not exist.

An electromagnetic wave shielding layer and a near infrared ray (NI
R) The one provided with a shielding layer was also excellent in electromagnetic wave shielding properties and near infrared (NIR) shielding properties. Furthermore, in order to form the laminate directly on the glass substrate via the transparent adhesive layer,
There is no air gap, and double exposure of external light and accumulation of dirt are eliminated.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view in which an impact relaxation laminate according to one embodiment of the present invention is bonded to a glass substrate.

FIG. 2 is a schematic cross-sectional view showing an example of the present invention, in which an impact relaxation laminate provided with an electromagnetic wave shielding layer and a near infrared (NIR) shielding layer is bonded to a glass substrate.

FIG. 3 is an explanatory view showing a method for measuring the impact force of a steel ball free fall according to one embodiment of the present invention.

FIG. 4 is a graph showing the results of measuring the impact force of a steel ball free fall according to one embodiment of the present invention.

FIG. 5 is an explanatory view showing a measuring method of a destructive test according to one embodiment of the present invention.

FIG. 6 is an explanatory diagram of a schematic sectional configuration of a seventh embodiment of the present invention.

FIG. 7 is an explanatory diagram of a schematic sectional configuration of an eighth embodiment of the present invention.

FIG. 8 is an explanatory diagram of a schematic sectional configuration of a ninth embodiment of the present invention.

FIG. 9 is an explanatory diagram of a schematic sectional configuration of a thirteenth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crack prevention layer 2 Crack prevention layer 3 Adhesive layer 4 FPD panel glass substrate 5 Shatterproof layer 10 Silver paste 11 Adhesive layer 12 Conductive patterning mesh

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 1/11 H01J 11/02 E 5/22 29/87 H01J 11/02 H04N 5/66 101A 29/87 G02B 1/10 Z H04N 5/66 101 A (72) Inventor Toshitaka Nakamura 1-1-2 Shimohozumi, Ibaraki City, Osaka Prefecture Inside Nitto Denko Corporation (72) Inventor Yukiko Azumi 1, Shimohozumi Ibaraki City, Osaka Prefecture 1-2, Nitto Denko Corporation

Claims (9)

[Claims] (1) 79,000 N (1.5 mx height)
A transparent shock-mitigating laminate formed on a glass panel substrate of a display device that is destroyed by an impact force corresponding to a weight of 510 g), wherein the laminate has a shear modulus of 2 × 10 ⁸ Pa or more. A scattering prevention layer, a crack prevention layer having a shear modulus in the range of 1 × 10 ⁴ to 2 × 10 ⁸ Pa and two or more different shear moduli, and a transparent pressure-sensitive adhesive layer. Transparent shock absorbing laminate. 2. The transparent shock absorbing laminate according to claim 1, further comprising a transparent electromagnetic wave shielding layer and / or a near-infrared shielding layer having a transmittance in the range of 800 to 1200 nm of 20% or less. 3. The transparent shock-absorbing laminate comprising a transparent pressure-sensitive adhesive layer and a crack-preventing and scattering-preventing layer, and a total thickness of an electromagnetic wave shielding layer and / or a near-infrared shielding layer is 5 mm or less, and the visible light transmittance thereof. Is 40% or more. 4. The transparent impact-relieving laminate according to claim 1, wherein the impact strength of a steel ball falling corresponding to an impact of 79,000 N is reduced to 50% or less. 5. The transparent shock-absorbing laminate shown in (A) below, wherein the scattering prevention layer and the crack prevention layer according to any one of claims 1 to 4 are composed of three or more layers. Layer, the order of the composition of the adhesive layer,
The order of lamination of each crack prevention layer is such that the sum of the absolute values of the logarithms of the shear modulus ratios of the upper and lower layer materials in contact with each interface of the crack prevention layer shown in the following equation (B) is the largest. Shock absorbing laminate. (A) Transparent impact-mitigating laminate: anti-scattering layer (1) / anti-cracking layer (2), anti-cracking layer (3) ... anti-cracking layer (n) / adhesive layer (B) Shear modulus (G) ) Sum of absolute values of logarithm of ratio: | Log G1 / G2 | + | Log G2 / G3 | +... + | Log Gn-1 / Gn
｜ + ｜ Log Gn / G adhesive layer ｜ 6. An electromagnetic wave shield and / or a near-infrared shield layer is included in the basic structure based on a pressure-sensitive adhesive layer / a crack prevention layer / a scattering prevention layer / an anti-reflection or anti-reflection protection layer. 5. The transparent impact-reducing laminate according to any one of 5. 7. The transparent impact relaxation laminate according to claim 1, wherein the transparent impact relaxation laminate is a filter for a plasma display. 8. A plasma display device, comprising the transparent shock-absorbing laminate according to claim 1. 9. A flat panel display device, wherein the transparent shock absorbing laminate according to claim 1 is bonded.