CN102947234A

CN102947234A - Optical glass

Info

Publication number: CN102947234A
Application number: CN2011800296185A
Authority: CN
Inventors: 此下聪子
Original assignee: Nippon Electric Glass Co Ltd
Current assignee: Nippon Electric Glass Co Ltd
Priority date: 2010-06-15
Filing date: 2011-06-13
Publication date: 2013-02-27
Also published as: JP2012140314A; JP5835642B2; WO2011158774A1

Abstract

The disclosed optical glass has a low glass transition temperature (Tg) and exhibits high clarity, excellent chemical durability, a low index of refraction, and low dispersion (specifically, an index of refraction (nd) between 1.48 and 1.54 and an Abbe number ( d) between 59 and 67). Said optical glass is characterized by containing essentially no PbO and containing, by mass, 45.5-70% SiO2, 10-44% B2O3, 7.2-20% Al2O3, 0-7% TiO2, 1-20% Na2O, 0-9% Li2O, 0-2% ZrO2, and less than 0.1% Sb2O3, with the sum of the amounts of Na2O, Li2O, and K2O being between 3% and 30% and the sum of the amounts of B2O3, Na2O, Li2O, and K2O divided by the sum of the amounts of Al2O3 and SiO2 being between 0.16 and 0.80.

Description

Opticglass

Technical field

The present invention relates to opticglass.

Background technology

The optical lens that picks up in CD, MD, DVD and other various optical disk systems, the imaging lens such as digital camera, pick up camera, attached camera mobile phone, the transmitting-receiving that is used for optical communication is with purposes such as lens, the so-called BK type glass that use that refractive index n d is 1.48～1.54, Abbe number ν d is 59～67 optical constant.

The glass that these are used for imaging lens extensively adopts so-called compression molding method, and it at first by the front end drippage melten glass of nozzle, makes first droplet-like glass, and premolding glass is made in then grinding, grinding, cleaning; Perhaps melten glass is carried out the chilling casting, make first glass block, then carry out equally grinding, grinding, cleaning, make premolding glass.Then, premolding glass is heated so that it becomes soft state, utilizes simultaneously and passed through precision machined mould and carry out extrusion forming, with the transferring surface shape of mould on glass.

Having presented BK type glass in the patent documentation 1～5 forms.

Technical literature formerly

Patent documentation

Patent documentation 1: the JP 2000-53441 of Japan communique

Patent documentation 2: the JP 2000-247678 of Japan communique

Patent documentation 3: the JP 2005-104824 of Japan communique

Patent documentation 4: the Unexamined Patent 5-193979 of Japan communique

Patent documentation 5: the JP 2002-201037 of Japan communique

Summary of the invention

The problem that invention will solve

The second-order transition temperature of disclosed glass is difficult to produce in batches by mold pressing up to more than 550 ℃ in the patent documentation 1.

On the other hand, disclose in the patent documentation 2～5 second-order transition temperature below 550 ℃, glass that the mold pressing mass productivity is high forms.But, although disclosed glass in the patent documentation 2,3 in order to improve chemical durability, contains TiO ₂As necessary component, TiO ₂Might make glass coloring, be unsuitable for the glass as the lens purposes.And TiO ₂So that glass high viscosity.Therefore, the clarification variation of glass in a lot of situations, needs a large amount of Sb as finings ₂O ₃

Disclosed glass in the patent documentation 4 because the viscosity under 1250～1300 ℃ of temperature is high, therefore might can't adopts by nozzle and naturally drip melten glass to form the method for droplet-like glass.In addition, because Al ₂O ₃Few, as therefore to exist the chemical durability such as acid resistance to reduce trend.Patent documentation 5 disclosed glass form B ₂O ₃Reach more than 37% with the total amount of alkaline components, therefore the low possibility of chemical durability is arranged.

The objective of the invention is in view of above-mentioned problem, provide the low-refraction that a kind of second-order transition temperature is low and clarification property is good, chemical durability is excellent the low opticglass that disperses (particularly, refractive index n d is 1.48～1.54, and Abbe number ν d is 59～67).

Solve the means of problem

Opticglass of the present invention is characterized in that % contains SiO in quality ₂45.5～70%, B ₂O ₃10～44%, Al ₂O ₃7.2～20%, TiO ₂0～7%, Na ₂O 1～20%, Li ₂O 0～9%, R ₂O 3～30%(R ₂O is Na ₂O, Li ₂O and K ₂The total amount of O), ZrO ₂0～2%, Sb ₂O ₃0～be lower than 0.1%, (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) be 0.16～0.80, and do not contain in fact PbO.In the present invention, adding PbO in " not containing in fact PbO " glass that refers to not have a mind, is not to mean to get rid of inevitable impurity fully.More objective, refer to comprise that the content of PbO of impurity is below 0.01%.In addition, " containing " term among the present invention for the component that is defined as " 0～", means also the situation that comprises that " 0% " does not namely contain fully.

In the present invention, be preferably in quality % and contain SiO ₂47～60%, B ₂O ₃10～35%, Al ₂O ₃7.2～20%, TiO ₂0～2%, Na ₂O 1～20%, Li ₂O 0～9%, R ₂O3～30%(R ₂O is Na ₂O, Li ₂O and K ₂The total amount of O), ZrO ₂0～2%, Sb ₂O ₃0～be lower than 0.1%, (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) be 0.16～0.80, and do not contain in fact PbO.

In the present invention, also be preferably and contain SO ₃0.005～0.5 quality %.

According to above-mentioned composition, owing to can improve the clarification of glass, therefore can realize higher bubble quality.

In the present invention, being preferably refractive index n d is 1.48～1.54, and Abbe number ν d is 59～67.

According to above-mentioned composition, opticglass of the present invention can be used as BK type glass.

In the present invention, be preferably second-order transition temperature below 530 ℃.

Glass of the present invention preferably adopts compression molding.

The manufacture method of opticglass of the present invention is characterized in that for the manufacture of above-mentioned glass, uses vitriol as finings.

According to above-mentioned composition, can make glass clarifying and be improved, steep the more excellent opticglass of quality.

In the method for the invention, the addition of vitriol is preferably below the 5 quality % with respect to frit 100 quality %.

The effect of invention

Opticglass of the present invention can be realized the low optical constant of disperseing of low-refraction for the optical lens that picks up optical lens of the various optical disk systems such as imaging lens of ordinary digital camera, pick up camera.Particularly realize easily 1.48～1.54 refractive index n d and 59～67 above Abbe number ν d.In addition, because high temperature viscosity is low, therefore, can be with the Sb of less than 1% ₂O ₃Realize clarification.And, because second-order transition temperature is low, can reduce molding temperature, therefore, glass ingredient is not volatile, can not cause the reduction of mould and die accuracy and the deteriorated and pollution of mould.And, because therefore good weatherability, can not cause deteriorated and surperficial the going bad of physical property in manufacturing process and goods use.Therefore, the production of the premolding glass of opticglass of the present invention is excellent.

Embodiment

Opticglass of the present invention is for to contain SiO in quality % ₂45.5～70%, B ₂O ₃10～44%, Al ₂O ₃7.2～20%, TiO ₂0～7%, Na ₂O 1～20%, Li ₂O 0～9%, R ₂O3～30%(R ₂O is Na ₂O, Li ₂O and K ₂The total amount of O), ZrO ₂0～2%, Sb ₂O ₃0～be lower than 0.1%, (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) be the SiO of 0.16～0.80 composition ₂-B ₂O ₃-Al ₂O ₃Class glass.In addition, the PbO component is not preferred component on environment, does not therefore contain in fact the PbO component.

In the said components, SiO ₂And Al ₂O ₃Have so that the effect that the specific refractory power of glass and Abbe number reduce.On the other hand, B ₂O ₃And Na ₂O has the effect that improves Abbe number.

In addition, R in the said components ₂O and B ₂O ₃Have and fall low-viscosity effect.In addition, if contain a large amount of R ₂O and B ₂O ₃, might be so that weathering resistance worsens, production reduces.On the other hand, although Al ₂O ₃And SiO ₂Have the effect that improves weathering resistance, but meeting so that presenting high viscosity, glass causes the deterioration of clarification property.Therefore, in the present invention, take the low viscosityization that has glass concurrently with prevent that weathering resistance from worsening as purpose, with (Al ₂O ₃And SiO ₂The total amount of amount) and (B ₂O ₃Amount and R ₂The total amount of O amount) ratio (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) to be adjusted to be 0.16～0.80 by quality ratio.When in the scope of this value 0.16～0.80, viscosity can be suppressed at lower value, and can realize the weathering resistance of production excellence.If (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) in 0.40～0.75 scope, just obtain especially easily the glass that has excellent weather resistance.

In addition, work as R ₂O and B ₂O ₃When total amount increased, the chemical durability of glass reduced.Particularly when the total amount of these components surpasses 37%, even with (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) be adjusted to take the scope of mass ratio as 0.16～0.80, also be difficult to realize good weathering resistance.Therefore, B ₂O ₃And R ₂The total amount of O is preferably below 37%.

In addition, although from the angle of clarification property, Sb ₂O ₃The more the better, but work as Sb ₂O ₃In the time of too much, during mold pressing, gonorrhoea appears in glass surface, and makes mold shape deteriorated, can shorten the life-span of mould.Therefore, Sb ₂O ₃The upper limit be limited in being lower than 0.1%.

Below, describe the reason of stipulating as mentioned above each component concentration in detail.In addition, if no special instructions, following " % " means " quality % ".

In the present invention, work as SiO ₂Content when few, be difficult to reduce specific refractory power, therefore, SiO ₂Content be set in more than 45.5%, preferably set more than 47%, more preferably be set in more than 50%.SiO ₂Content when too much, the high temperature viscosity of glass is high, the deterioration of clarification property.In addition, second-order transition temperature rises, and moldability worsens.From above-mentioned reason, SiO ₂Content should be set in below 70%, preferably sets below 65%, more preferably is set in below 60%, further preferably sets below 59%, particularly preferably is set in below 58%.

B ₂O ₃Have the raising Abbe number, reduce glass adhesion, and the effect that second-order transition temperature is reduced.But when containing a large amount of B ₂O ₃The time, chemical durability obviously worsens, and particularly acid resistance obviously worsens.In addition, the volatilization during owing to mold pressing is too much, and molding die is deteriorated.Based on this reason, B ₂O ₃Content should be limited to 10～44%, preferably be limited to 12～40%, more preferably be limited to 15～35%, further preferably be limited to 16～25%, particularly preferably be limited to 17～22%.

Al ₂O ₃It is the component of Effective Raise chemical durability.Even R particularly ₂O content is the glass of the high basic metal content more than 13%, can improve acid resistance, water tolerance and weathering resistance.But when containing a large amount of Al ₂O ₃The time, the viscosity of the glass under the high temperature increases, and clarification property significantly worsens.And second-order transition temperature significantly improves, and moldability worsens.Al ₂O ₃Content be 7.2～20%, be preferably 7.5～18%, more preferably 8～15%, be particularly preferably 8.5～11%.

Na ₂O, Li ₂O and K ₂High temperature viscosity, the raising clarification property of O for reducing glass, the component of reduction second-order transition temperature.And has the effect that reduces specific refractory power.

Be used for expression alkalimetal oxide (Na ₂O, Li ₂O, K ₂The R of total amount O) ₂The content of O is set in more than 3%, is preferably more than 5%, more than 8%, more than 10%, more than 13%, more than 14.5%, is particularly preferably to be set in more than 15%.On the other hand, work as R ₂When O content was too much, the amount from the glass volatilization during mold pressing also increased, and meeting is so that molding die is deteriorated.In addition, the volatilization during melting also increases, so that melting kiln or melting utensil are deteriorated, mass productivity worsens.Based on this reason, R ₂O content should be set in below 30%, is preferably below 25%, more preferably is lower than 18%.

In basic component, Na ₂O has the effect of special reduction high temperature viscosity, is the essential component that realizes excellent clarification.In addition, it reduces also very effective to second-order transition temperature, can reduce molding temperature.Na ₂The content of O is set in more than 3%, is preferably more than 6%, is particularly preferably more than 7%.Na ₂When O content was too much, weathering resistance reduced.In addition, volatilization when mold pressing, can occur, pollute mould.Based on this reason, Na ₂The content of O should be set in below 20%, be preferably below 15%, more preferably below 12%, is particularly preferably below 9.5%.

Although Li ₂O is not necessary component, but preferably contains more than 1%, particularly preferably contains more than 2.5%.But, work as Li ₂When O content is too much, the tendency that has the weathering resistance of making to worsen.Work as Li ₂When the content of O surpasses 9%, even with (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) to be adjusted to mass ratio be 0.16～0.80, also reduce easily chemical durability, and weathering resistance is significantly worsened.In addition, in glass of the present invention, meeting is so that the improper raising of specific refractory power.Based on this reason, Li ₂The content of O should be limited in below 9%, more preferably below 7%, is particularly preferably below 5%.

K ₂O and Na ₂O or Li ₂O has the high temperature viscosity that reduces glass, the effect that improves clarification property equally.In addition, with Na ₂O and Li ₂O compares, and having not can be so that the specific refractory power change reduces viscosity, or reduces the effect of second-order transition temperature.K ₂The content of O is preferably 0～10%, and more preferably 1～8%, more preferably 2～7%, be particularly preferably 3～5.5%.

ZrO ₂Content below 2%.Work as ZrO ₂Content when surpassing 2%, specific refractory power is too high, is difficult to the specific refractory power that obtains expecting, in addition, even (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) value be set as more than 0.16, also be difficult to fully reduce the viscosity of glass, the deterioration of clarification property is difficult to second-order transition temperature is controlled at below 530 ℃.ZrO ₂Content be lower than 1%.Must use ZrO if not having ₂The origin of an incident, also can not contain ZrO ₂

Sb ₂O ₃Content be 0～be lower than 0.1%.Sb ₂O ₃There is the deaeration effect, and has the painted effect that inhibition Pt ion (sneaking into several ppm as impurity in glass) causes.But, work as Sb ₂O ₃Content when many, gonorrhoea can appear in glass surface during mold pressing.And because Sb ₂O ₃Have strong oxidizing power, therefore, when its content is too much, can with burnings such as the Pt that uses in the melt container or Rh, reduce mass productivity.Sb ₂O ₃Preferred content be 0～0.09%, be particularly preferably 0～0.08%.

In addition, in the present invention, except said components, also various components can be added, for example, TiO can be added ₂, ZnO, MgO, CaO, BaO, SrO, La ₂O ₃, Gd ₂O ₃, Y ₂O ₃, Nb ₂O ₅, Ta ₂O ₅, GeO ₂, P ₂O ₅Deng.

TiO ₂Content preferably below 7%.TiO ₂Content when too much, glass can be obviously painted, it is too high that specific refractory power becomes, and is difficult to the specific refractory power that obtains expecting.In addition, be difficult to second-order transition temperature is controlled at below 530 ℃.And work as TiO ₂Content when surpassing 7%, (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂Even) value more than 0.16, also be difficult to fully reduce the viscosity of glass, the deterioration of clarification property.Work as TiO ₂Content 0.1% when above, can improve the acid resistance of glass, but because to produce the possibility of above-mentioned rough sledding very high, therefore, TiO ₂Content preferably below 2%, be particularly preferably and be lower than 1%.Must not use TiO if having ₂The origin of an incident, do not contain TiO in order reliably to avoid the problem of painted and clarification property, to be preferably ₂

ZnO, MgO, CaO, BaO and SrO can be used as the adjusting of optical constant for improving the component of specific refractory power, but when the content of each component surpassed 5%, weathering resistance reduced.The preferable range of each component is respectively 0～1% for being respectively 0～3%, being particularly preferably.

La ₂O ₃, Gd ₂O ₃, Y ₂O ₃For keeping Abbe number and improving the component of specific refractory power, can be as the adjusting of optical constant.When the content of each component surpasses 5%, be difficult to refractive index n d is controlled at below 1.54.The preferable range of each component is for being lower than respectively 1%.

Nb ₂O ₅, Ta ₂O ₅For significantly improving the component of specific refractory power, can be as the adjusting of optical constant.When the content of each component surpasses 2%, be difficult to refractive index n d is controlled at below 1.54.The preferable range of each component is for being lower than respectively 1%.

GeO ₂Can add for the purpose of the stability that improves glass and specific refractory power.But because GeO ₂Be scarce raw materials, therefore, when usage quantity increased, it is very high that raw materials cost also can become.Therefore, even use GeO ₂, its content also is preferably less, particularly, is preferably 0～3%, more preferably 0～1%, is particularly preferably 0～0.001%.

P ₂O ₅Can be in the purpose of regulating second-order transition temperature and viscosity characteristics and add.But because the weathering resistance of glass reduces, devitrification resistance worsens, therefore, preferred content is not a large amount of.Therefore, even use P ₂O ₅, its content is also preferably less, particularly, is preferably 0～10%, more preferably 0～1%.Must use P if not having ₂O ₅The origin of an incident, be preferably and do not contain P ₂O ₅

In addition, except foregoing, as long as without detriment to glass properties, also can add other component

For example, in order to improve clarification, can add finings.Wherein, it is effective using the vitriol such as sodium sulfate, vitriolate of tartar, calcium sulfate, barium sulfate, Strontium Sulphate, Tai-Ace S 150.When using vitriol, in the time of 1200～1500 ℃, discharge limpid bubble, can be with glass limpidization effectively.But, when the usage quantity of vitriol is too much, can produce SO during mold pressing ₂Gas pollutes mould, or because excessive limpid effect, makes that glass is remaining a bubble.It is below the 5 quality % that the addition of vitriol is preferably with respect to frit 100 quality %, more preferably below the 1 quality %.In addition, the SO during gained glass forms ₃Amount be preferably 0.005～0.5 quality %, be particularly preferably 0.01～0.3 quality %.

As the finings beyond the vitriol, also can consider to use SnO ₂, CeO ₂But, because SnO ₂With Sb ₂O ₃Might when mold pressing, make equally glass surface produce gonorrhoea, therefore, should avoid adding in a large number SnO ₂SnO ₂Content be preferably and be lower than 0.1%.And because CeO ₂Therefore might cause paintedly, should avoid a large amount of interpolations.CeO ₂Content be preferably and be lower than 0.1%.And, Sb ₂O ₃, SnO ₂And CeO ₂Total amount be preferably be lower than 0.1%, more than 0.001%.

In addition, owing to the As that is widely known by the people as finings ₂O ₃Be harmful to, therefore, be preferably and do not contain in fact As ₂O ₃In addition, because the F component might cause detrimentally affect to environment, therefore preferably do not contain in fact the F component.Because the Cl component is easy to volatilize from glass, can significantly promote the deteriorated of molding die, therefore preferably do not contain in fact the Cl component when mold pressing.At this, " do not contain in fact As ₂O ₃", " not containing F " and " not containing in fact Cl " refer to, add these components in the glass that do not have a mind, and be not to mean to get rid of inevitable impurity fully.More objective, mean the content of these components that contain impurity, As ₂O ₃Below 0.00001%, F is below 0.01%, and Cl is below 0.01%.

In addition, Cu, Ag are so that the component of glass coloring, are preferably not contain Cu, Ag.

Opticglass with above composition can realize easily that refractive index n d is 1.48～1.54, Abbe number ν d is 59～67 optical constant.Particularly can access have that refractive index n d is 1.50～1.52, the glass of optical constant that Abbe number ν d is 60～63 scope.

In addition, have the opticglass of above-mentioned composition, realize easily the second-order transition temperature below 530 ℃.Also realize easily below 520 ℃, the second-order transition temperature below 510 ℃ particularly.

In addition, with the viscosity of 1300 ℃ of suitable glass 10 ^2.0DPas is following, more preferably 10 ^1.9Below the dPas.Viscosity in the time of 1300 ℃ is in above-mentioned scope the time, and bubble contained in the glass floats easily, therefore realizes easily limpid.

At the thick internal transmission coefficient (λ of the 10mm of 330nm _330nm) more than 85%, more preferably more than 88%.When the internal transmission coefficient is in above-mentioned scope, even the large lens of diameter also can be kept high transmissivity.In order to obtain above-mentioned internal transmission coefficient, can be by the Fe that sneaks in the manufacturing process of selecting raw material ₂O ₃Measuring the less means such as oxide compound realizes.For example, the raw material of MgO and CaO contains Fe ₂O ₃Situation as impurity is a lot, in such situation, preferably avoids using MgO and CaO.In addition, Fe ₂O ₃Preferably below 40ppm.

Then, the method for using opticglass manufacturing of the present invention to pick up optical lens and imaging lens etc. is described.

At first, it is the composition of expectation that frit is in harmonious proportion, afterwards, and melting in glass melting furnace.

Based on using Sb ₂O ₃Or vitriol is as finings, and the melt temperature of glass is preferably more than 1150 ℃.More preferably more than 1200 ℃, be particularly preferably more than 1250 ℃.But be the glass coloring that the penetration that prevents from the Pt of the platinum that consists of melt container brings, melt temperature is preferably below 1450 ℃, more preferably below 1400 ℃, more preferably below 1350 ℃, is particularly preferably below 1300 ℃.

In addition, if the fusion time is too short, might be able to not fully clarify, therefore, the fusion time is preferably more than 2 hours, more preferably more than 3 hours.But be the glass coloring that the penetration that prevents from the Pt that consists of melt container brings, the fusion time was preferably in 8 hours, was particularly preferably in 5 hours.

In addition, because the degree of depth of glass melt in the melt container crosses meeting when shallow so that the productivity variation, so this degree of depth is preferably more than 30mm, is particularly preferably more than 50mm.On the other hand, cross when dark when this degree of depth, the come-up of bubble needs the expensive time, so this degree of depth is preferably below 1m, is particularly preferably below 0.5m.

Then, make melten glass from the front end drippage of nozzle, make first droplet-like glass, obtain premolding glass.In addition, melten glass is carried out the chilling casting, temporarily make glass block, carry out grinding, grinding, cleaning, obtain premolding glass.

Then, in having passed through precision machined mould, put into premolding glass, be heated to soft state and extrusion forming, arrive the die surface shape transferred thereon on glass.This forming method is called as compression molding method, is widely used.So just can access and pick up optical lens or imaging lens.

Embodiment

Below, based on embodiment opticglass of the present invention is elaborated.

Table 1～3 expression embodiments of the invention (sample No.1～11), table 4 expression comparative example (sample No.12～16).

Table 1

Table 2

Table 3

Table 4

Each sample of following making.

At first, add blending and be the frit (carbonate, oxide compound) of table 1～4 described compositions in platinum crucible, the difference melting is 2 hours under 1300 ℃ temperature.Wherein, in the present embodiment, as Na ₂The O raw material uses sode ash.Then, flow out melten glass at carbon plate, after the cooling curing, anneal, make sample.The sample that so obtains is estimated various performances, the results are shown in each table.

Wherein, in order to confirm the Fe in the glass ₂O ₃Amount is dissolved glass by acid solution, measures with ICP, and No.6 is 30ppm, and No.7 is 20ppm.Relative therewith, No.10 contains a large amount of MgO, therefore, and Fe ₂O ₃Reach 50ppm.

Refractive index n d adopts refractometer (Kalneur KPR-200 processed), represents with the observed value in the d line (wavelength 587.6nm) of helium lamp.

Abbe number ν d uses refractometer (Kalneur KPR-200 processed), measure respectively the specific refractory power of the C line (wavelength 656.3nm) of the F line (wavelength 486.1nm) of above-mentioned d line, hydrogen lamp and hydrogen lamp, the value of { (nd-1)/(nF-nC) } when these values are made as respectively nd, nF, nC.

Second-order transition temperature (Tg) by the low temperature zone in the thermal expansion curve straight line and the intersection point of the straight line in high-temperature zone obtain.

Water tolerance is estimated based on the measuring method (powder method) of JOGIS chemical durability.

Acid resistance is estimated based on the measuring method (powder method) of JOGIS chemical durability.

Weathering resistance confirms that for the surface of maintenance after 24 hours under the condition of 60 ℃ of observations, 90%RH, surface not having gonorrhoea is " zero ", confirms that it is " * " that gonorrhoea is arranged.

As follows the carrying out of evaluation of clarification property.At first, glass pulverizing, classification with temporary transient moulding form the following pulverizing glass of 2mm.Then, in the 300cc platinum crucible, drop into pulverizing glass, regulate amount of glass, so that glass height is 30mm.Then, then insulation 1 hour under 1300 ℃ temperature carries out mirror ultrafinish to being configured as the thick plate shaped sample of 10mm in electric furnace, from sample laterally inject directional light, calculate the bubble number.

Be equivalent to 1300 ℃ glass viscosity, rise the ball method by the platinum ball and measure.

By the record of showing as can be known, the refractive index n d of each sample of the No.1 of embodiments of the invention～11 is 1.485～1.530, and Abbe number ν d is 57.8～64.1.And second-order transition temperature is 490～530 ℃.In addition, the viscosity under 1300 ℃ temperature is 10 ^1.2～10 ^2.0DPas, the bubble number in the glass is every 1cm ³It is 0～4.JOGIS water tolerance (powder method) is 1～3 grade, and the weathering resistance evaluation also is good.

Relative therewith, in comparative example No.12,13,15, the viscosity under 1300 ℃ temperature is 10 ^2.2～10 ^3.2DPas, and the bubble number is 5～20/cm ³, clarification property is low.And the second-order transition temperature of No.15 is up to 560 ℃, is contemplated to be difficult to carry out compression molding.The JOGIS water tolerance (powder method) of No.14 is 5 grades, and weathering resistance is poor.The Al of No.16 ₂O ₃Few, JOGIS acid resistance (powder method) is 4 grades, the batch production rate variance.

In addition, in order to confirm the clarifying effect of vitriol, prepare Na ₂The part of O raw material is replaced into the sample of vitriol, uses method same as above, estimates the bubble number.Particularly, as No.3,6,8 and the Na of No.11 ₂The O raw material, sodium sulfate (Na ₂SO ₄) be 0.1～0.02%, all the other are sode ash, make sample, are used for estimating.

Table 5

Table 6

The result is shown in table 5, table 6, and arbitrary to have used the bubble number average of the sample of vitriol be 0/g.

In addition, the SO in the glass ₃Amount is by using alkali dissolution glass, this solution is carried out ion-exchange after, measure with ion chromatography.

The present invention has been described in detail with reference to particular implementation.But only otherwise break away from the spirit and scope of the present invention, can carry out various changes and correction, this is self-evident for those skilled in the art.

In addition, the application is based on the Japanese patent application (Patent 2010-277730) of the Japanese patent application (Patent 2010-135760) that proposed on June 15th, 2010 and proposition on December 14th, 2010, and its whole content is incorporated herein by reference.At this, the reference content that should be incorporated in this is introduced as a whole.

Claims

1. an opticglass is characterized in that % contains SiO in quality ₂45.5～70%, B ₂O ₃10～44%, Al ₂O ₃7.2～20%, TiO ₂0～7%, Na ₂O 1～20%, Li ₂O 0～9%, R ₂O 3～30%, ZrO ₂0～2%, Sb ₂O ₃0～be lower than 0.1%, (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) be 0.16～0.80, and do not contain in fact PbO, wherein, R ₂The content of O is Na ₂O, Li ₂O and K ₂The total amount of O.

2. opticglass as claimed in claim 1 is characterized in that, % contains SiO in quality ₂47～60%, B ₂O ₃10～35%, Al ₂O ₃7.2～20%, TiO ₂0～2%, Na ₂O 1～20%, Li ₂O 0～9%, R ₂O 3～30%, ZrO ₂0～2%, Sb ₂O ₃0～be lower than 0.1%, (B ₂O ₃+ R ₂O)/(Al ₂O ₃+ SiO ₂) be 0.16～0.80, and do not contain in fact PbO, wherein, R ₂The content of O is Na ₂O, Li ₂O and K ₂The total amount of O.

3. opticglass as claimed in claim 1 or 2 is characterized in that, also contains SO ₃0.005～0.5 quality %.

4. opticglass as claimed in claim 1 or 2 is characterized in that, refractive index n d is 1.48～1.54, and Abbe number ν d is 59～67.

5. opticglass as claimed in claim 1 or 2 is characterized in that, second-order transition temperature is below 530 ℃.

6. opticglass as claimed in claim 1 or 2 is characterized in that, uses in compression molding.

7. the manufacture method of an opticglass is characterized in that, for the manufacture of claim 1 or 2 described opticglass, uses vitriol as finings.

8. the manufacture method of opticglass as claimed in claim 7 is characterized in that, the addition of vitriol is below the 5 quality % with respect to frit 100 quality %.