CN109775983A - A kind of alkali-free alumina silicate glass of not boracic - Google Patents

Abstract

A kind of alkali-free alumina silicate glass of not boracic, it solves boron oxide in existing alkali-free alumina silicate glass and causes the technical issues of strain point of glass reduces, glass density is big, elasticity modulus is not high enough and clarifying agent improper use, the technical solution adopted is that, the constituent of the alkali-free glass and by mole calculate proportion include: SiO268.5 ~ 72.5%, Al2O312.5 ~ 16%, MgO2 ~ 6%, CaO3.5 ~ 5.5%, SrO0.5 ~ 3.5%, BaO1 ~ 5%, ZnO0.5-4%.Present invention chemical stability with higher, strain point with higher, Young's modulus with higher, with higher than modulus, transmitance with higher has lower fusion temperature, has lower liquidus temperature, has lower density.

Description

A kind of alkali-free alumina silicate glass of not boracic

Technical field

The invention belongs to glass manufacturing area, it is related to a kind of alkaline earth aluminates glass and its component, not alkali metal containing.This Invention is a kind of environmental type glass, chemical stability and mechanical performance with higher；With the lower coefficient of expansion and Liquidus temperature；It is widely portable to glass substrate, photovoltaic device or other phototubes that production plane shows and illuminates The glass substrate of part, the industries glass composition such as glass.Especially a kind of alkali-free alumina silicate glass of not boracic.

Background technique

With the fast development of photovoltaic industry, the demand to various display devices constantly increases, such as active matrix The active matrix liquid crystal display device of liquid crystal display, Organic Light Emitting Diode and application low-temperature polysilicon silicon technology, these displays Device, which is all based on, produces thin-film transistor technologies using thin film semiconductor material.The silicon substrate TFT of mainstream can be divided into non-crystalline silicon tft, Multi-crystal TFT and monocrystalline silicon TFT, wherein non-crystalline silicon tft is the technology of present mainstream TFT-LCD application, and non-crystalline silicon tft technology exists Treatment temperature in procedure for producing can be completed at a temperature of 300 ~ 450 DEG C.And LTPS multi-crystal TFT needs in the fabrication process Repeatedly processing, substrate must cannot deform in multiple high temp treatment process at relatively high temperatures, this is just to base plate glass More stringent requirements are proposed for performance, and preferred strain point is higher than 650 DEG C, more preferably above 670 DEG C, 700 DEG C, 720 DEG C, with Make substrate that there is thermal contraction small as far as possible in panel processing procedure, therefore the higher the better for the strain point temperature of substrate.Glass base simultaneously The thermal expansion coefficient of plate needs the similar thermal expansion coefficient with silicon, as far as possible reduction stress and destruction, therefore base plate glass is preferred Thermal linear expansion coefficient between 28 ~ 39 × 10-7/ DEG C.For the ease of production, production cost is reduced, as display base plate Glass should have lower fusion temperature and liquidus temperature.

For the glass substrate that plane is shown, need through technologies such as sputtering, chemical vapor depositions in underlying substrate glass Surface forms transparent conductive film, insulating film, semiconductor film and metal film, then forms various circuits and figure by optical lithography Shape, if glass contains alkali metal oxide, alkali metal ion diffuses into deposited semiconductor material, meeting during heat treatment Semiconductor film characteristic is damaged, therefore, TFT glass should be free of alkali metal oxide.The prior art, it is preferred that with SiO2, Al2O3, B2O3, alkaline earth oxide MgO, CaO, SrO etc. are the alkaline earth aluminates glass of principal component.

The strain point of most of silicate glasses with the increase of glass former content and the reduction of modifier content and Increase.But it will cause high temperature melting simultaneously and clarification be difficult, cause refractory material to corrode aggravation, increase energy consumption and production cost. Therefore, it is improved by component, so that low temperature viscosity will also guarantee that high temperature viscosity is not in big promotion while increase, even Reduce the best breach for being only and improving strain point.

In high-aluminum alkali-free silicate glass system, addition boron oxide B2O3 can bring good fluxing effect, simultaneously Be conducive to promote glass endurance.But in low temperature viscosity area, B2O3 but significantly reduces strain point of glass, then how same The endurance and strain point temperature of Shi Tigao glass substrate just become a difficult problem of long-standing problem those skilled in the art.

In the process of glass substrate, base plate glass be it is horizontal positioned, glass has certain journey under Gravitative Loads Degree it is sagging, sagging degree is directly proportional to the density of glass, is inversely proportional with the elasticity modulus of glass.With substrate manufacture towards Large scale, the development for being thinned direction, the sagging of glass plate must draw attention in manufacture.Therefore composition should be designed, makes substrate Glass has alap density and elasticity modulus as high as possible.

It is universal with smart phone and tablet computer, open the epoch of intelligent mobile.Previous mobile phone is confined to lead to Communication function, but the performance of the smart machine at present including smart phone and tablet computer is close with notebook, and people rely on nothing The convenience of line communication, all the time not in the commercial affairs and recreation for executing and enjoying higher level.Under such trend, Requirement to display performance is also being continuously improved, especially to the image quality of intelligent movable equipment, visuality outdoors It can require also promoted, while in order to mitigate the use burden of handheld device, thinning become of weight, thickness can not be kept away The main trend exempted from.Under the guidance of this trend, display panel develops to the direction that lightening, ultra high-definition is shown, face Plate making technology manages temperature development to higher height；Simultaneously monolithic glass pass through process, thickness reach 0.25mm, 0.2mm, 0.1mm is even more thin.The mode for keeping glass thinning is presently mainly chemical reduction, specifically, uses hydrofluoric acid or hydrofluoric acid Buffer corrodes glass substrate, and thinning principle is as follows:

Main chemical reactions: 4HF+SiO2=SiF4+2H2O,

Secondary chemical reaction: RO+2H+=R2++H2O(R represents alkaline-earth metal etc.).

Surface quality and parent glass composition after chemical reduction technique and thinning glass substrate have certain relationship, existing TFT-LCD base plate glass frequently occurs the bad deficient point such as " pit ", " sags and crests " during chemical reduction, needs to carry out secondary Polishing is directly discarded, increases the production cost of glass substrate.Glass with high chemical stability has after being thinned There is better surface quality, therefore research and develop the TFT-LCD base plate glass of high chemical stability, it is possible to reduce the production such as second polishing Cost promotes product quality and yields, has larger benefit for large industrialized production.

With the development of lightening trend, in the higher generations glass substrate productions such as G5 generation, G6 generation, G7 generation, G8 generation, water The glass substrate of placing flat due to self weight generate it is sagging, be warped into emphasis research topic.For the glass substrate producer, Glass board material will be by a variety of links such as annealing, cutting, processing, inspection, cleanings after forming, and the sagging of sized rectangular glass substrate will Influence to transport loading in the cabinet of glass, the ability taken out and separated between processing stand.It is similar for panel manufacturers Problem equally exists.Biggish sag or warpage will lead to fragment rate raising and the alarm of CF making technology, seriously affect product Yield.If the maximum sag of chain (S) of glass substrate can be expressed as follows at both ends supporting substrate both sides:

K is constant, and ρ is density, and E is elasticity modulus, and l is support interval, and t is thickness of glass substrate.Wherein, (ρ/E) is than mould Several inverses.It is knot also known as " than elasticity modulus " or " specific stiffness " than the ratio that modulus refers to elasticity modulus of materials and density Structure designs one of the important requirement to material.It is higher than modulus illustrate under same stiffness that material weight is lighter or phase homogenous quantities under It is more rigid.By above formula as it can be seen that when mono- timing of l, t, ρ, which becomes smaller after E is increased, can reduce sag of chain, therefore should make base plate glass Have density low as far as possible and elasticity modulus high as far as possible, that is, there is ratio modulus big as far as possible.Glass after being thinned is due to thickness It strongly reduces and mechanical strength reduction occurs, it is easier to deform.It reduces density, increase than modulus and intensity, reduce glass brittleness The factor for needing emphasis to consider as glass production person.

Use about clarifying agent: still alkali-free glass in order to obtain is expelled from glass melts using fining gases The gas that generates when glass reacts, in addition homogenize melt when, need to increase alveolar layer using the fining gases generated again Diameter, makes its floating, thus takes out the small bubble of participation.

It, need to be with higher temperature melting but the viscosity of the glass melts as glass substrate for plane display device is high.? In such glass substrate, usually cause Vitrification at 1300 ~ 1500 DEG C, at a high temperature of 1500 DEG C or more deaeration, Matter.Therefore, in clarifying agent, clarification gas can be generated between 1300 ~ 1700 DEG C in wider temperature range by being widely used The As2O3 of body.But the toxicity of As2O3 is very strong, glass manufacturing process or cullet processing when, it is possible to pollute Environment and the problem for bringing health are used and are being restricted.In the prior art, once trial is clear come substitute for arsenic with antimony clarification Clearly.However, there is also influence environment and health aspect to antimony itself.Although the toxicity of Sb2O3 is high unlike As2O3, But Sb2O3 is still virose.And compared with arsenic, the temperature that antimony generates fining gases is lower, removes such glass gas The validity of bubble is lower.

Therefore, how to obtain it is a kind of with higher endurance, high strain-point, low-density, high elastic modulus base plate glass As a great problem for being stranded right those skilled in the art.

Summary of the invention

The present invention is to solve boron oxide in existing alkali-free alumina silicate glass to cause strain point of glass reduction, glass density Greatly, the technical issues of elasticity modulus is not high enough and clarifying agent improper use, provide it is a kind of it is environmentally friendly, performance is more perfect Not boracic alkali-free alumina silicate glass, in the glass ingredient, even if not adding B2O3, glass substrate still has compared with Gao Naihua Property, even if clarifying agent does not use As2O3 and Sb2O3, also there is no the formulas of the glass substrate as surface defect.Matched using this Glass substrate made from side meets environmental requirement, is free of As2O3, Sb2O3 and its compound, while glass with higherization Stability, strain point with higher, Young's modulus with higher are with higher than modulus, transmission with higher Rate has lower fusion temperature, has lower liquidus temperature, has lower density, meets FPD industry hair Exhibition trend is suitable for merging a variety of molding modes manufacturings such as glass tube down-drawing, float glass process.

The present invention be realize goal of the invention the technical solution adopted is that, a kind of alkali-free alumina silicate glass of not boracic, Key is: the constituent of the alkali-free glass and by mole calculate proportion include:

SiO268.5 ~ 72.5%,

Al2O312.5 ~ 16%,

MgO2 ~ 6%,

CaO3.5 ~ 5.5%,

SrO0.5 ~ 3.5%,

BaO1 ~ 5%,

ZnO0.5-4%。

The beneficial effects of the present invention are: the 1, present invention has environment friendly, any poisonous and harmful substance, clarifying agent are free of It is readily available substance, and known no detrimental nature using stannous oxide SnO, SnO, it is used alone as glass fining agent When, there is the higher temperature range for generating fining gases, is suitble to the elimination of such glass blister；2, pass through control SiO2+Al2O3 >83%, MgO/R ' O<0.4, ZnO/R ' O<0.4, (MgO+ZnO)/R ' O>0.3, O<1.0 0.8<Al2O3/R ', can make glass simultaneously It is chemical stability with higher, strain point, Young's modulus, more excellent than modulus and lower fusion temperature, liquidus temperature etc. Characteristic；3, the glass substrate produced by means of glass ingredient formula provided by the invention can achieve technology below through detection Index: 10%HF acid solution (22 DEG C/20min) erosion amount < 4.5mg/cm2；It is 31~38 in 50~350 degree of thermal expansion coefficients ×10-7/℃；Strain point is at 740 DEG C or more；Density is less than 2.65g/cm3, and liquidus temperature is lower than 1140 DEG C, per kilogram glass Bubbles number of the bubble diameter in > 0.1mm is invisible in substrate；4, due to the higher SiO2 that contains in instant component with Al2O3 resultant, and B2O3 is free of in component, it ensure that high strain-point, a certain proportion of MgO+ZnO that arranges in pairs or groups can be effectively reduced molten Change temperature, larger space is brought to producing line Yield lmproved, while the production costs such as fuel, electric power are also minimized.

Specific embodiment

A kind of alkali-free alumina silicate glass of not boracic, key are: the constituent and massage of the alkali-free glass Your percentage calculates proportion

SiO268.5 ~ 72.5%,

Al2O312.5 ~ 16%,

MgO2 ~ 6%,

CaO3.5 ~ 5.5%,

SrO0.5 ~ 3.5%,

BaO1 ~ 5%,

ZnO0.5-4%。

By mole calculating in the constituent of the alkali-free glass: SiO2+Al2O3 > 83%.

By mole calculating in the constituent of the alkali-free glass: O < 0.4 MgO/R ', wherein R ' O=MgO+CaO +SrO+BaO+ZnO。

By mole calculating in the constituent of the alkali-free glass: O < 0.4 ZnO/R ', wherein R ' O=MgO+CaO +SrO+BaO+ZnO。

By mole calculating in the constituent of the alkali-free glass: O > 0.3 (MgO+ZnO)/R ', wherein R ' O= MgO+CaO+SrO+BaO+ZnO。

By mole calculating in the constituent of the alkali-free glass: O < 1.0 0.8 < Al2O3/R ', wherein R ' O= MgO+CaO+SrO+BaO+ZnO。

Also contain SnO in the constituent of the alkali-free glass, with Mole percent meter, the addition range of SnO is: 0.05 ~0.1%。

By mole calculating in the constituent of the alkali-free glass: the preferred scope of Al2O3 is 13 ~ 14.5%.

By mole calculating in the constituent of the alkali-free glass: the preferred scope of ZnO is 0.6 ~ 3%.

By mole calculating in the constituent of the alkali-free glass: the preferred scope of SiO2 is 69 ~ 71%.

The present invention first will include raw material that above-mentioned each glass substrate corresponds to oxide molar percent composition when implementing After uniform stirring mixing, then by mixed raw material melt-processed, discharge bubble is stirred with platinum stick and is homogenized glass metal, then will Its temperature is reduced to glass substrate forming temperature range required for molding, and by annealing theory, producing flat-panel screens is needed The thickness for the glass substrate wanted, then simple cold work is carried out to molding glass substrate, finally to the base of glass substrate This physical characteristic, which carries out test, becomes qualified products.

In the present invention, the molar content of SiO2 is 68.5~72.5%.SiO2 is glass former, if content is too low, no Conducive to the corrosive enhancing of endurance, the coefficient of expansion can be made too high, glass is easy devitrification；It is light that raising SiO2 content facilitates glass Quantization, thermal expansion coefficient reduce, and strain point increases, and chemical resistance increases, but high temperature viscosity increases, and is unfavorable for melting in this way, one As kiln be difficult to meet, so the content of SiO2 be 68.5~72.5%.

The molar content of Al2O3 is 12.5~16%, to improve the intensity of glass structure, if content is lower than 12.5%, and glass Glass is easy devitrification, is also easy the erosion by extraneous aqueous vapor and chemical reagent.The A12O3 of high-content facilitate strain point of glass, Bending strength increases, but excessively high glass is easy to appear crystallization, while glass can be made to be difficult to melt, therefore A12O3 Content is 12.5~16%.

MgO, which has, to be substantially improved glass Young's modulus and than modulus, reduces high temperature viscosity, the spy for making glass be easy to melt Point.When alkaline-earth metal resultant is less in alkali-free silicate glass, the biggish network-modifying ion Mg2+ of electric field strength is introduced, is held Local accumulation effect is easily generated in the structure, increases nearest neighbour distance.More intermediate oxygen is introduced in this case Compound Al2O3, since these polyhedrons have negative electricity, has been attracted subnetwork outer cationic, made in the presence of [AlO4] state The accumulation degree of glass, the decline of crystallization ability；When alkaline-earth metal resultant is more, network fracture is compared under serious situation, introducing MgO can make the oxygen-octahedron of fracture reconnect and decline devitrification of glass ability.Therefore when adding MgO it is noted that with The mixing ratio of other components.Relative to other alkaline earth oxides, the presence of MgO can bring the lower coefficient of expansion and close Degree, higher chemically-resistant, strain point and elasticity modulus.If MgO is greater than 6mol%, glass endurance can be deteriorated, while glass holds Easy devitrification.It is unfavorable that too low content of MgO comparison modulus improves.Therefore its content is 2 ~ 6mol%.

The molar content of CaO is 3.5~5.5%, melting and adjustment glass mouldability of the calcium oxide to promote glass.Such as Fruit calcium oxide content is less than 3.5%, is not easy to reduce the viscosity of glass, and content is excessive, and crystallization, thermal expansion system would tend to occur in glass Number also can substantially become larger, unfavorable to follow-up process.So the content of CaO is 3.5~5.5%.

The molar content of SrO is 0.5~3.5%, and strontium oxide strontia is as fluxing agent and prevents glass from crystallization occur, if content Excessively, glass density can be too high, leads to the mole overweight of product.So the content of SrO is determined as 0.5~3.5%.

The content of BaO is 1~5%, and barium monoxide is similar to the effect of strontium oxide strontia, and content is excessive, and the density of glass can become larger, And strain point will be greatly reduced.So the content of SrO is determined as 1~5%.

The molar content of ZnO be 0.5 ~ 4%, bivalent metal oxide according to it in the periodic table of elements status with to property Influence difference, can be divided into two classes: one kind is the alkaline earth oxide positioned at main group, and ion R2+ has 8 exoelectron knots Structure；Second class is located at periodic table subgroup (such as ZnO, CdO), and ion R2+ has 18 outer electronic structures, and in glass two The configuration state of person is different on glass property influence.ZnO can reduce high temperature viscosity of glass (such as 1500 degree), be conducive to Eliminate bubble；Have below softening point simultaneously and promote intensity, hardness, the chemical resistance for increasing glass, reduces glass thermal expansion system Several effects.In alkali-free glass system, adding appropriate ZnO helps to inhibit crystallization, can reduce crystallization temperature.In theory On, ZnO in alkali-free glass, after introducing glass as network outer body, generally exists under high temperature in the form of [ZnO4], compared with [ZnO6] glass structure is more loose, and compared with being under the identical condition of high temperature with the glass without ZnO, the glass containing ZnO is viscous Degree is smaller, and atomic motion speed is bigger, can not form nucleus, needs to further decrease temperature, is just conducive to the formation of nucleus, because And reduce the crystallization ceiling temperature of glass.ZnO content excessively can be such that the strain point of glass is greatly lowered.So ZnO's contains Amount is determined as 0.5 ~ 4 mole of %.

In the present invention, the stannous oxide SnO of 0.05~0.1mol% can also be added in glass composition, it is molten as glass Clarifying agent or defrother when solution, to improve the melting mole of glass.If content is excessive, glass substrate devitrification, institute will lead to It is no more than 0.1mol% with its additive amount.

Claims (8)

1. a kind of alkali-free alumina silicate glass of not boracic, it is characterised in that: the constituent of the alkali-free glass and by mole Percentage calculates proportion are as follows:

SiO268.5 ~ 72.5%,

Al2O312.5 ~ 13.3%,

MgO3.6 ~ 6%,

CaO3.5 ~ 5.5%,

SrO0.5 ~ 3.5%,

BaO3.7 ~ 5%,

ZnO0.5-4%；

By mole calculating in the constituent of the alkali-free glass: SiO2+Al2O3 > 83%；

By mole calculating in the constituent of the alkali-free glass: O < 0.4 MgO/R ', wherein R ' O=MgO+CaO+SrO +BaO+ZnO。

2. a kind of alkali-free alumina silicate glass of not boracic according to claim 1, it is characterised in that: the alkali-free glass Constituent in by mole calculating: O < 0.4 ZnO/R ', wherein R ' O=MgO+CaO+SrO+BaO+ZnO.

3. a kind of alkali-free alumina silicate glass of not boracic according to claim 1, it is characterised in that: the alkali-free glass Constituent in by mole calculating: O > 0.3 (MgO+ZnO)/R ', wherein R ' O=MgO+CaO+SrO+BaO+ZnO.

4. a kind of alkali-free alumina silicate glass of not boracic according to claim 1, it is characterised in that: the alkali-free glass Constituent in by mole calculating: O < 1.0 0.8 < Al2O3/R ', wherein R ' O=MgO+CaO+SrO+BaO+ZnO.

5. a kind of alkali-free alumina silicate glass of not boracic according to claim 1, it is characterised in that: the alkali-free glass Constituent in also contain SnO, with Mole percent meter, the addition range of SnO is: 0.05 ~ 0.1%.

6. a kind of alkali-free alumina silicate glass of not boracic according to claim 1, it is characterised in that: the alkali-free glass Constituent in by mole calculating: the preferred scope of Al2O3 is 13 ~ 13.3%.

7. a kind of alkali-free alumina silicate glass of not boracic according to claim 1, it is characterised in that: the alkali-free glass Constituent in by mole calculating: the preferred scope of ZnO is 0.6 ~ 3%.

8. a kind of alkali-free alumina silicate glass of not boracic according to claim 1, it is characterised in that: the alkali-free glass Constituent in by mole calculating: the preferred scope of SiO2 is 69 ~ 71%.