CN102923950A

CN102923950A - Fluorophosphate glass and method for producing the same and near-infrared absorbing filter

Info

Publication number: CN102923950A
Application number: CN2012102800515A
Authority: CN
Inventors: 池西干男; 丹野义刚
Original assignee: Hoya Corp
Current assignee: Hoya Corp
Priority date: 2011-08-11
Filing date: 2012-08-08
Publication date: 2013-02-13
Anticipated expiration: 2032-08-08
Also published as: KR20130018177A; CN102923950B; KR101566218B1

Abstract

The invention provides a fluorophosphate glass and method for producing the same and near-infrared absorbing filter. The fluorophosphate glass has a following ratio of O2-/P5+ even after produced and has weather ability. The ratio of O2-/P5+ is set according to a manner that the absorbable near-infrared light able to add while inhibiting the amount of Cu2+ of adsorbing degree of visible light. The fluorophosphate glass is capable of adsorbing near-infrared light because of containing Cu2+. The molar ratio (O2-/P5+) of the content of O2- in the fluorophosphate glass relative to that of the P5+ is more than 3.2 but less than 3.4. The molar ratio (F-/(O2-+F-)) of the content of F- in the fluorophosphate glass relative to total amount of the O2- and the F- is more than 0.05 but less than 0.25.

Description

Fluophosphate glass and manufacture method thereof and near-infrared absorption strainer

Technical field

The present invention relates to fluophosphate glass and manufacture method thereof and near-infrared absorption strainer, particularly can absorb fluophosphate glass and manufacture method and the near-infrared absorption strainer of near infrared light.

Background technology

Fluophosphate glass is very useful as the glass with weathering resistance and low dispersion glass, and is known to patent documentation 1～6 described glass as this glass.

Yet, based on the composition that can access required optical characteristics, to frit concoct, heating and melting, make thus in the situation of fluophosphate glass, usually have following problem.

Fluophosphate glass generally demonstrates significant volatility during fabrication.The detrimentally affect that brings as the volatilization of melten glass exists: near surface or the inner such problem of brush line that produces of glass; Because the glass composition that causes that volatilizees changes, so the characteristic of glass can change along with the time such problem.

In addition, in manufacturing process, because generating phosphorus oxyfluoride (POF ₃) and produce volatilization.Further, the phosphorus oxyfluoride of volatilization also can produce hydrogen fluoride (HF) because of hydrolysis, thereby causes producing the white cigarette that contains these compounds.These compounds might produce infringement with equipment to glass manufacture, therefore usually need to seek the countermeasure of above problem.Therefore, in order to deal with the by product of volatilization, need to pay great expense, and also can increase operating personnel's burden.

In order to improve this situation, the inventor investigates described volatile reason, and the result is disclosed in the patent documentation 7～10.The summary of its content is as follows.

In the situation of making fluophosphate glass, the normal operation phosphatic raw materials, but many as far as possible in order to make as the import volume of the fluorion of anionic component, phosphoric acid salt uses the Sauerstoffatom metaphosphate less than (Sauerstoffatom/phosphorus atom) with respect to the quantity of 1 phosphorus atom, and (Sauerstoffatom (O)/phosphorus atom (P)=3 is PO ₃).Because this reason, in the glass commonly used of hexafluorophosphoric acid system, the amount of Sauerstoffatom mostly is 3 with the ratio of the amount of phosphorus atom up to now.

But the inventor studies, and found that, when only to make oxygen/phosphorus ratio be 3 glass as oxide raw material with metaphosphate, in melten glass, react from metaphosphoric acid and the fluorine of raw material, demonstrate obvious volatile phosphorus oxyfluoride (POF thereby cause producing ₃).Relative therewith, if known metaphosphate oxide raw material or the use pyrophosphate salt in addition that append, Sauerstoffatom in the melten glass is adjusted into (Sauerstoffatom/phosphorus atom 〉=3.5) more than 3.5 with respect to the atomic ratio of per 1 phosphorus atom, and then the generation of volatile matter can significantly reduce.It is believed that this is because as existing phosphoric acid in the melten glass, is that 3 metaphosphoric acid compare with respect to the quantity of 1 phosphorus atom than (Sauerstoffatom/phosphorus atom) with Sauerstoffatom, and Sauerstoffatom/phosphorus atom is that (tetra-sodium is P for 3.5 bisphosphate ₂O ₇) more stable.

Based on above opinion, in order to suppress described volatilization, the inventor is conceived to the O in the fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) or raw material in the content of contained Sauerstoffatom with respect to the mol ratio (O/P) of the content of phosphorus atom, having expected making these values is method such more than 3.5, and discloses the method in patent documentation 7～10.

Need to prove that in patent documentation 11, the applicant discloses too and made these values is method such more than 3.5.

In addition, the inventor discloses in patent documentation 12, makes the O in the fluophosphate glass ^2-Content with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) be more than 3.4, make the F in the fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio of total content is method such more than 0.05.

Below, for convenience of description, the oxygen in the fluophosphate glass (is labeled as O ^2-) content (is labeled as P with respect to phosphorus ⁵⁺) mol ratio of content is called " O ^2-/ P ⁵⁺Than ", oxygen contained in the raw material (is labeled as O.) content (is labeled as P with respect to phosphorus.) mol ratio (O/P) of content is called " raw material O/P ratio ".

The prior art document

Patent documentation

Patent documentation 1: Japanese kokai publication hei 10-139454 communique

Patent documentation 2: Japanese kokai publication hei 6-16451 communique

Patent documentation 3: Japanese kokai publication hei 8-253341 communique

Patent documentation 4: Japanese kokai publication hei 3-232735 communique

Patent documentation 5: Japanese kokai publication hei 1-219073 communique

Patent documentation 6: Japanese kokai publication hei 3-83834 communique

Patent documentation 7: TOHKEMY 2010-59019 communique

Patent documentation 8: TOHKEMY 2010-59021 communique

Patent documentation 9: TOHKEMY 2010-59022 communique

Patent documentation 10: TOHKEMY 2010-59023 communique

Patent documentation 11: TOHKEMY 2011-132077 communique

Patent documentation 12: TOHKEMY 2011-93757 communique

Summary of the invention

The problem that invention will solve

Before the problem of the present invention being wanted solve describes, from the principle aspect, in described patent documentation 7～10, making O ^2-/ P ⁵⁺Than being that reason more than 3.5 is described in detail.

Before described patent documentation 7～10 discloses, as mentioned above, in the glass commonly used of hexafluorophosphoric acid system, usually make O ^2-/ P ⁵⁺Than being 3.O ^2-/ P ⁵⁺Than being 3 o'clock, in glass, thereby O and P bonding form rectangular P-O-P chain.Because a plurality of these P-O-P chains are orientated or twine, be that glass is qualified as the glass that is used for practical application thereby make hexafluorophosphoric acid.

But, at O ^2-/ P ⁵⁺When being 3, if there is fluorine (F), the possibility that the key of O in this P-O-P chain and P is cut off by F can appear then.Its result might produce the above-mentioned volatile matter (POF as by product ₃And HF).In order to prevent this situation, in described patent documentation 7～10, used following principle: compared with the past, further improve O ^2-/ P ⁵⁺Than (that is, containing more oxygen (O)), thereby can cut off the P-O-P chain by O in advance before the P-O-P chain is cut off by F, (be PO thereby make the metaphosphoric acid structure ₃) to be changed to the tetra-sodium structure (be P ₂O ₇).

On the other hand, the inventor has also found following problem: by improving O ^2-/ P ⁵⁺Ratio can make and contain Cu ²⁺C be that glass absorbs near infrared light, descend but also can cross the practicality that causes by force as optical filter because of visible Optical Absorption.Specifically, the inventor finds, when forming the tabular fluophosphate glass of pre-determined thickness, adds Cu with the degree that can absorb near infrared light to raw material ²⁺Situation under, if O ^2-/ P ⁵⁺Than high, then with O ^2-/ P ⁵⁺Than being to compare in 3 o'clock, can exceedingly absorb visible light, even drop into the Cu of the amount that can absorb the near infrared light degree ²⁺As raw material, then can cause specifically exceedingly absorbing visible light.

In addition, the following opinion that obtains of the inventor: O ^2-/ P ⁵⁺Than bringing impact can for the excessive absorption for visible light, and in view of this impact, has the O that sets for solving described problem in order to make the fluophosphate glass after the manufacturing ^2-/ P ⁵⁺Ratio must be considered the amount of the fluorine (F) in the glass.Detailed content will be narrated in the back.

The object of the present invention is to provide a kind of fluophosphate glass and manufacture method thereof and near-infrared absorption strainer, even described fluophosphate glass also has following O after manufacturing ^2-/ P ⁵⁺Ratio, and possess weathering resistance, described O ^2-/ P ⁵⁺Than being to absorb the Cu of amount that near infrared light suppresses the degree of visible Optical Absorption simultaneously according to adding ²⁺Mode set.

For the means of dealing with problems

At first, the inventor has continued to use the inventor's the policy of patent documentation 7～10 described technology as basic principle.That is, at first adopted following policy: (3.0) were compared with in the past, O ^2-/ P ⁵⁺Than improving, suppress thus the volatilization of by product.Thus, as mentioned above, can the P-O-P chain be cut off to suppress POF by utilizing in advance O ₃Generation.In addition by inference, the P-O-P chain also might the atmosphere when making fluophosphate glass in contained water molecules be cut off, therefore by in advance the P-O-P chain is cut off to a certain degree weathering resistance being improved.

On the other hand, at O compared with the past ^2-/ P ⁵⁺In situation about improving, need to improve the F in the fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio of total content.This be because, by improving O ^2-/ P ⁵⁺Ratio, the P-O-P chain is cut off by O, therefore can form the glass of glass forming ability decline, easily remarkable crystallization.Therefore, by improving above-mentioned F in the glass ^-The mol ratio of content can make F between between the tetra-sodium structure, maintains the similar cut structure of P-O-P chain.Thus, fluophosphate glass can be used for practical application.

Below, for convenience of description, with the F in the fluophosphate glass ^-Content (is labeled as O with respect to oxygen ^2-) and fluorine (be labeled as F ^-) total content (O ^2-+ F ^-) mol ratio (F ^-/ (O ^2-+ F ^-)) be called " F ^-Than ", fluorine contained in the raw material (is labeled as F.) content (is labeled as O with respect to oxygen.) and fluorine (be labeled as F.) the mol ratio (F/O+F) of total content (O+F) be called " raw material F ratio ".Wherein, describe in the back the method that has adopted volatile matter substantially not produce among the present invention in detail.Therefore, above-mentioned raw materials F than with product glass in F ^-Than being identical in fact.

Get back to topic in talk, by improving O ^2-/ P ⁵⁺It (is P that P-O-P chain in the ratio, glass mostly is the tetra-sodium structure ₂O ₇).Like this, other metal (Li etc.) and tetra-sodium structure bonding in the glass also might form crystallization.If in glass, produce crystallization, then can produce the result that optical characteristics significantly descends.As its countermeasure, by in glass, improving F ^-Ratio, thus make F between between the tetra-sodium structure.Thus, can suppress the formation of described crystallization.

Herein, the O among the embodiment in the selection patent documentation 2～6 ^2-/ P ⁵⁺Than for surpassing 3.0 numerical value and less than 3.5 embodiment, for O ^2-/ P ⁵⁺And F ^-Than being made into table look-up, it is shown in table 1.As shown in table 1, raising O compared with the past ^2-/ P ⁵⁺Than the time, if to possess sufficient weathering resistance as target, in any case usually will make F ^-Than nearly being at least more than 0.30, this is those skilled in the art's general knowledge.

Table 1

	O ^2-/P ^5-Ratio	F ^-Ratio	Remarks
				The embodiment 3 of patent documentation 2	3.473744	0.006025	Contain Pb
The comparative example 11 of patent documentation 2	3.068565	-	Contain B ³⁺, do not contain F ^-
				The comparative example 12 of patent documentation 2	3.182688	-	Do not contain F-
The ratio embodiment 1 of patent documentation 3	3.134901	0.661544	-
				The embodiment 7 of patent documentation 3	3.149881	0.733764	-
The embodiment 8 of patent documentation 3	3.079777	0.337624	-
				The embodiment 11 of patent documentation 3	3.260386	0.467068	-
The embodiment 18 of patent documentation 3	3.394710	0.444594	-
				The comparative example 25 of patent documentation 3	3.020058	0.405389	-
The embodiment 2 of patent documentation 5	3.031390	0.215221	Contain Pb
				The embodiment 5 of patent documentation 5	3.480060	0.484436	-
The embodiment 8 of patent documentation 5	3.461567	0.558856	-
				The embodiment 9 of patent documentation 5	3.237104	0.609943	-
The embodiment 10 of patent documentation 5	3.359127	0.275487	Contain Pb
				The embodiment 1 of patent documentation 6	3.363245	0.343490	-
The embodiment 3 of patent documentation 6	3.011756	0.191647	Contain Pb
				The embodiment 5 of patent documentation 6	3.432149	0.541318	Contain Pb
The embodiment 6 of patent documentation 6	3.404429	0.375737	-
				The embodiment 7 of patent documentation 6	3.128491	0.292533	Contain Pb
The embodiment 8 of patent documentation 6	3.363245	0.338950	-
				The embodiment 9 of patent documentation 6	3.324640	0.405765	Contain Pb
The embodiment 10 of patent documentation 6	3.322762	0.400466	-

Need to prove, in patent documentation 12, record and make O ^2-/ P ⁵⁺Than being more than 3.4, making F ^-Than being more than 0.05, but the reduction of the spectrophotometric transmittance (following also only be called " transmitance ") during the λ 50=615nm near infrared light zone (1200nm) rests on (with reference to the embodiment (following table of table 1) of patent documentation 12) about 23%.As its reason, it is believed that to have following cause-effect relationship: even in visible region (615nm), also can carry out the thickness of glass attenuation of certain Optical Absorption → cause λ 50=615nm → because therefore the thickness of glass attenuation can't fully carry out the near infrared Optical Absorption.

The inventor is on one side based on above-mentioned condition, and one side is studied above-mentioned problem.As a result, till finishing the present invention, roughly be divided into 3 opinions below having obtained.

[opinion 1] is for containing Cu ²⁺Fluophosphate glass carry out absorption spectrum (transverse axis: wave number (K (kayser=cm ^-1))) analysis the time, till near-infrared wavelength～visible wavelength, have a peak.But this peak can be separated into 2 peaks: infrared light side peak and visible light side peak.And the intensity at visible light side peak can be subject to O ^2-/ P ⁵⁺The impact of ratio.

[opinion 2] raw material F than high situation (or the high situation of melt temperature) and at least in feed stage with O ^2-/ P ⁵⁺In near situation about being set in 3.0, even have predetermined O according to final glass composition ^2-/ P ⁵⁺The mode of ratio is mixed to the raw material of intended component, from feed stage to the glass manufacture latter stage till, O in fact ^2-/ P ⁵⁺Than also changing because of by product.That is, the O in the product glass ^2-/ P ⁵⁺Than being subject to raw material F than the impact of (or melt temperature).

[opinion 3] in [opinion 2], the O that changes till from feed stage to the glass manufacture latter stage ^2-/ P ⁵⁺Than being about 3.3.This 3.3 this numeric representation tripolyphosphate structure (is P ₃O ₁₀).

Below, for each opinion be described in detail on one side, the process of finishing in conjunction with the present application on one side describes.

At first describe for [opinion 1], for containing Cu ²⁺Fluophosphate glass carry out the analysis of absorption spectrum, show the result in Fig. 1.And it is Cu that the absorption peak among this Fig. 1 can be divided into originally ²⁺For the infrared light side peak (little) of Absorption Line with compare the visible light side peak (greatly) that is positioned at short wavelength side (being high wave number side) with infrared light side peak.The results are shown in Fig. 2.Need to prove, in this Fig. 2 (a), make O ^2-/ P ⁵⁺Than being 3.5; In this Fig. 2 (b), make O ^2-/ P ⁵⁺Than being 3.18.

As seen from Figure 2, to be divided into be Cu originally to the absorption peak in the measured spectra (with the solid line of ◇) ²⁺For the infrared light side peak (dotted line) of Absorption Line with compare the visible light side peak (solid line) that is positioned at short wavelength side with infrared light side peak.In addition, to Fig. 2 (a) and Fig. 2 (b) when comparing, O as can be known ^2-/ P ⁵⁺Intensity than a low side's (being Fig. 2 (b)) visible light side peak is low.Need to prove that for width and the intensity at infrared light side peak, both sides almost do not have difference, also almost do not have difference for the width both sides at visible light side peak.In addition, for the peak position, both sides almost do not have difference yet.

Need to prove that the final spectrophotometric transmittance of obtaining has comprised the loss that is caused by surface reflection.For this loss is included in the consideration, in absorbancy, also to consider the loss (pecked line) that is caused by surface reflection.Yet in Fig. 2, in general, the variable quantity of the reflectivity that is caused by the variation of specific refractory power is little, and therefore no matter how wavelength will calculate reflectivity according to definite value.

Need to prove, product glass surveyed the spectrum (with the solid line of ◇) that obtains and the regular distribution spectrum (being infrared light side peak and visible light side peak) that is divided into behind 2 peaks is overlapped, the synthetic spectrum (dash line) that obtains in conjunction with the loss that is caused by surface reflection simultaneously is almost consistent.

Herein, when judge making and to have certain thickness and certain near-infrared absorption ability the situation of plate glass of (transmitance during wavelength 1200nm (about 8300K) is 10% specifically), consideration O ^2-/ P ⁵⁺Than high glass (Fig. 2 (a)) and O ^2-/ P ⁵⁺Result than low glass (Fig. 2 (b)).That is, in order to obtain required plate glass, should improve the intensity at the infrared light side peak in the absorption spectrum so that the transmitance of plate glass in the near infrared light zone can reach 10%, and need to further add Cu in feed stage ²⁺

So, further adding Cu ²⁺Situation under, for fluophosphate glass, its absorption spectrum is predicted, show the result in Fig. 3.And, based on Fig. 3, the transmitance of light in plate glass predicted, will the results are shown in Fig. 4.Need to prove Fig. 3 (a) and Fig. 4 (a) expression predicting the outcome for Fig. 2 (a); Fig. 3 (b) and Fig. 4 (b) expression predicting the outcome for Fig. 2 (b).

As shown in Figure 3, if further add Cu ²⁺So that product glass has certain near-infrared absorption ability (transmitance during wavelength 1200nm (about 8300K) is 10%) (dotted line → heavy line), the strength increase at infrared light side peak (two-dot chain line → fine line) not only then, the intensity at visible light side peak also can further increase (long and short dash line → solid line).At this moment, shown in Fig. 2 (a), if O ^2-/ P ⁵⁺Than high, then near the intensity of visible light side peak (for example the about 830nm of wavelength (about 12000K)) is originally just very high, by further interpolation Cu ²⁺, it is very strong that the absorption of visible light side becomes.Its result shown in Fig. 4 (a), has excessive receptivity in visible region (for example wavelength 500nm), cause the transmitance of fluophosphate glass in the visible region to descend.

On the contrary, if O ^2-/ P ⁵⁺Than low, then shown in Fig. 2 (b), the intensity at visible light side peak is originally very low, by further interpolation Cu ²⁺, the transmitance in the time of can making wavelength 1200nm (about 8300K) is 10%, the result can make the absorption of visible light side can not become so strong.Its result, shown in Fig. 4 (b), the transmitance of fluophosphate glass makes fluophosphate glass have the receptivity of appropriateness in the visible region, and the transmitance of fluophosphate glass in the visible region can be kept higher value.

By above result, and based on the inventor's wholwe-hearted effort, finally obtained following opinion: making to absorb the fluophosphate glass of near infrared light the time O ^2-/ P ⁵⁺Than exerting an influence to having till the visible light to absorb.

The inventor has not only obtained this [opinion 1], also conducts in-depth research based on this [opinion 1], and the result has further obtained above-mentioned [opinion 2].Below, [opinion 2] is described in detail.

Fig. 5 be the raw material of expression in fluophosphate glass raw material O/P constantly than and the fluophosphate glass manufacturing after the chart of relation of transmitance.At this moment, for each raw material F ratio, a series of each plotting is shown.Need to prove that making melt temperature is 1000 ℃.

In addition, among Fig. 5, for the plotting of each raw material F ratio, change thickness of glass, the intensity at visible light side peak equated, but except " raw material F ratio ", " thickness of glass ", " raw material O/P ratio " (for example with Cu ²⁺Other composition for representative), all be same.

In Fig. 5, raw material F ratio is 0.04 and 0.08 o'clock as can be known, and is such such as proof [opinion 1], when the intensity that makes visible light side peak is constant in each is marked and drawed, and along with raw material O/P ratio uprises, O ^2-/ P ⁵⁺Uprise than also, cause therefrom the strength degradation (being that transmitance rises) at infrared light side peak.Specifically, in each chart, be constant restriction because added the intensity that makes visible light side peak, so if raw material O/P (is O than height ^2-/ P ⁵⁺Than high), then can only add a small amount of Cu because of the intensity at visible light side peak itself with regard to very high causing ²⁺Its result causes the strength degradation at infrared light side peak, and transmitance rises.

On the other hand, raw material F ratio is 0.11 and 0.15 o'clock as can be known, recently cooperates even change raw material O/P in feed stage, and when finally forming glass, transmitance does not almost have difference.Namely, if based on [opinion 1], even then changing raw material O/P in feed stage as can be known recently cooperates, mark and draw at each that (for example raw material F is than being in 0.15 o'clock the chart, raw material O/P is than being 3.05 point and 3.09 point) between, the difference of final composition when forming glass little (, form and have almost identical O ^2-/ P ⁵⁺The glass of ratio).

In order to review its reason, the inventor has further carried out appending experiment.Specifically, the raw material F in Fig. 5 is than being that the situation different to melt temperature (being respectively 900 ℃ and 1000 ℃) tested in 0.5 the situation.Figure as its result is shown in Fig. 6.

Observe Fig. 6 as can be known, rise by making melt temperature, described tendency is further obvious.That is, promoted reaction by melt temperature is risen as can be known, even recently cooperate at feed stage feed change O/P thus, when final formation glass, transmitance is identical, and then is almost constant O ^2-/ P ⁵⁺Ratio.

Based on Fig. 5 and Fig. 6, the inventor is studied for the reason of this phenomenon.Results presumption, the rising because POF of this phenomenon ₃Thereby volatilization causes the glass composition to be compared with feed stage, and variation has occured.Just because of this, if infer that raw material F than high, has then promoted POF ₃Volatilization, final close to constant O ^2-/ P ⁵⁺Than (about 3.3).In addition, carry out same supposition, rise by making melt temperature, promoted POF ₃Volatilization, final close to constant O ^2-/ P ⁵⁺Ratio.That is, O ^2-/ P ⁵⁺Than being affected than (or melt temperature) because of raw material F.In other words, the O in the product glass ^2-/ P ⁵⁺Than controlling than (or melt temperature) by raw material F.

Above idea is summarized, thereby obtained above-mentioned [opinion 2].

By from diverse viewpoint this [opinion 2] being studied, can obtain [opinion 3].That is, for final close to constant O in [opinion 2] ^2-/ P ⁵⁺Than (about 3.3) this situation, finally be O even it is contemplated that fluophosphate glass ^2-/ P ⁵⁺Composition (tetra-sodium structure) than=3.5 is for fluophosphate glass O ^2-/ P ⁵⁺The composition (tripolyphosphate structure) more such than=3.3 also is a rock steady structure as the intermediate stage, and optical characteristics etc. are difficult to change because of the change of creating conditions.Can obtain [opinion 3] by this imagination.

Based on [opinion 1] that so obtain～[opinion 3], in order to obtain because containing Cu ²⁺And can absorb near infrared light but do not absorb in fact the such fluophosphate glass of visible light, the inventor has carried out following research.

Can moderately contain Cu ²⁺Be subject to O ^2-/ P ⁵⁺The impact of ratio.This O ^2-/ P ⁵⁺Than the impact that is subject to raw material F ratio or melt temperature.This impact is caused by the material volatilization that exists in feed stage.That is, think if raw material F originally can not produced the lower degree of volatilization than being set as, prevent that O or P break away from from raw material, then can eliminate described impact, can make the fluophosphate glass after the manufacturing really have the Cu that can drop into suitable amount ²⁺O ^2-/ P ⁵⁺Ratio.Need to prove, by doing like this, can substantially not produce volatilization, thus raw material F than with make after glass in F ^-Than being identical in fact.Further, raw material O/P than with make after glass in O ^2-/ P ⁵⁺Identical in fact than also.

Need to prove, for F ^-Compare, although make O ^2-/ P ⁵⁺Than being higher than in the past, and have sufficient weathering resistance, reduced F but compare with patent documentation 2～6 ^-Ratio, this idea are the idea opposite with general knowledge to those skilled in the art.Such as previously described, by improving O ^2-/ P ⁵⁺Ratio, the O in the P-O-P chain and the key of P are cut off by F, and strength of glass descends, thereby might make weathering resistance deteriorated.In addition, other metal and tetra-sodium structure bonding in the glass also might form crystallization.Therefore in order to prevent these situations, improve the F in the glass ^-Than being general knowledge.

But the inventor is not confined to such general knowledge, has carried out reducing the F in raw material F ratio and the glass ^-The trial of ratio.Further, the inventor is to F ^-Ratio and O ^2-/ P ⁵⁺Than studying, so that along with F ^-The decline of ratio, O ^2-/ P ⁵⁺Than being higher than in the past and for suitable value, and can add an amount of Cu ²⁺As concrete numerical example, based on [opinion 3], established O ^2-/ P ⁵⁺Than be near 3.3 numerical value (in other words, by 3.3 or close to 3.3 value centered by numerical value in the scope of the one fixed width that is worth) target, and to compared with the past, with raw material F than and F ^-The method of very little value is studied than being set as.

Need to prove that the raw material F that reaches with respect to it for melt temperature compares and F ^-Than and with respect to their volatilization degree, the inventor furthers investigate.

Need to prove, in above-mentioned patent documentation 12, really record and make O ^2-/ P ⁵⁺Than be more than 3.4, F ^-Than being more than 0.05.But, in patent documentation 12, about the open or hint of above-mentioned [opinion 1]～[opinion 3], do not have with further interpolation Cu yet ²⁺The time the visible region in light absorpting ability and the Optical Absorption ability in the near infrared light zone be the record of problem.In witness whereof, in the embodiment of patent documentation 12, the reduction of the transmitance (λ 50=615nm) in the near infrared light zone (1200nm) rests on about 23%.

Based on above opinion and result of study and the mode of the present invention of finishing is as follows.

The 1st mode of the present invention is a kind of fluophosphate glass, and it is because containing Cu ²⁺And can absorb the fluophosphate glass of near infrared light, it is characterized in that the O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) be more than 3.2 and less than 3.4, the F in the described fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) be more than 0.05 and below 0.25.

Wherein, described fluophosphate glass does not contain B ³⁺, Pb and ion and compound and Tl and ion and its compound.

The 2nd mode of the present invention is the described mode of the 1st mode, it is characterized in that, the rare earth class ion content in the described fluophosphate glass is more than the 0.5 positively charged ion % and below the 2.0 positively charged ion % with respect to the ratio of the content of whole cation constituents.

The 3rd mode of the present invention is the described mode of the 1st or the 2nd mode, it is characterized in that, in the spectrophotometric transmittance of fluophosphate glass, for the thickness that demonstrates 50% transmitance in wavelength 615nm, the transmitance of its wavelength 1200nm is less than 15%.

The 4th mode of the present invention is a kind of near-infrared absorption strainer, it is characterized in that, this near-infrared absorption strainer has used the 1st to the 3rd the described fluophosphate glass of arbitrary mode.

The 5th mode of the present invention is a kind of manufacture method of fluophosphate glass, and it is by frit being concocted, described frit is carried out melting, thereby makes because containing Cu ²⁺And can absorb the method for the fluophosphate glass of near infrared light, it is characterized in that,

The composition of described fluophosphate glass is set as O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) be more than 3.2 and less than 3.4 and described fluophosphate glass in F ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) be more than 0.05 and below 0.25, based on the described composition of setting frit is concocted, produce thus glass.

The 6th mode of the present invention is the described mode of the 5th mode, it is characterized in that,

Described frit contains fluorine, oxygen, phosphorus at least,

Be described frit is concocted and to be more than 0.05 with respect to the mol ratio of the total content of oxygen and fluorine and 0.25 following mode is concocted described frit according to the fluorine content in the described frit more than 3.2 and less than 3.4 mode according to the content of oxygen contained in the described frit with respect to the mol ratio of the content of phosphorus, produce thus glass.

The 7th mode of the present invention is the described mode of the 5th or the 6th mode, it is characterized in that, making the rare earth class ion content in the described fluophosphate glass is more than the 0.5 positively charged ion % and below the 2.0 positively charged ion % with respect to the ratio of the content of whole cation constituents, and making melt temperature is below 1000 ℃.

The 8th mode of the present invention is the described mode of the 5th to the 7th arbitrary mode, it is characterized in that, in the spectrophotometric transmittance of fluophosphate glass, for the thickness that demonstrates 50% transmitance in wavelength 615nm, the transmitance of its wavelength 1200nm is less than 15%.

The invention effect

According to the present invention, can provide a kind of fluophosphate glass and manufacture method thereof and near-infrared absorption strainer, even this fluophosphate glass also has following O after manufacturing ^2-/ P ⁵⁺Ratio, and possess weathering resistance, described O ^2-/ P ⁵⁺Than being to absorb the Cu of amount that near infrared light suppresses the degree of visible Optical Absorption simultaneously according to adding ²⁺Mode set.

Description of drawings

Fig. 1 is for O ^2-/ P ⁵⁺Than the product glass of=3.5 (comparative examples 1), the chart when carrying out the mensuration of optical transmission spectra of 500nm～1500nm, in this chart, transverse axis is transformed to wave number, and (K is cm ^-1), the longitudinal axis is transformed to absorbancy (arbitrary unit).

Among Fig. 2, be at O (a) ^2-/ P ⁵⁺(be O than high situation ^2-/ P ⁵⁺Ratio=3.5 (comparative examples 1)) in the chart, infrared light side peak is separated the chart that obtains with visible light side peak.(b) be at O ^2-/ P ⁵⁺(be O than low situation ^2-/ P ⁵⁺Ratio=3.18 (reference examples 1)) in the chart, infrared light side peak is separated the chart that obtains with visible light side peak.

Among Fig. 3, (a) be chart with respect to Fig. 2 (a), be that 10% mode makes absorption spectrum multiply by the chart that coefficient obtains according to the transmitance of product glass in 1200nm (about 8300K), herein, being equivalent to make separately the size of spectrum is that 1.22 times, thickness are 1.22 times.(b) be chart with respect to Fig. 2 (b), be that 10% mode makes absorption spectrum multiply by the chart that coefficient obtains according to the transmitance of product glass in 1200nm (about 8300K), being equivalent to make separately the size of spectrum herein, is that 1.4 times, thickness are 1.4 times.

Among Fig. 4, be that chart with Fig. 3 (a) is transformed to transverse axis: wavelength (nm), the longitudinal axis: the chart during transmitance (%) (a).(b) be that chart with Fig. 3 (b) is transformed to transverse axis: wavelength (nm), the longitudinal axis: the chart during transmitance (%)

Fig. 5 is to be in the situation of 50% the mode thickness of regulating product glass according to the transmitance among the wavelength 615nm, with the transmitance among the wavelength 1200nm as the longitudinal axis, raw material O/P is compared to transverse axis, the chart that each raw material F is obtained than marking and drawing.

Fig. 6 is to be in the situation of 50% the mode thickness of regulating product glass according to the transmitance among the wavelength 615nm, and the transmitance among the wavelength 1200nm as the longitudinal axis, raw material O/P is compared to transverse axis, is marked and drawed and the chart that obtains each melt temperature.

Embodiment

Below, for embodiments of the present invention, describe in the following order.

1. the manufacture method of fluophosphate glass

2. fluophosphate glass

3. by the embodiment produce an effect

Other

＜1. the manufacture method of fluophosphate glass 〉

The fluophosphate glass of present embodiment is by the blending frit, and described frit melting made obtains.And this fluophosphate glass is because containing Cu ²⁺And have an ability that absorbs near infrared light.

In the making of this fluophosphate glass, according to the O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺The mol ratio of content (that is, O ^2-/ P ⁵⁺) be more than 3.2 and less than 3.4 and described fluophosphate glass in F ^-Content is with respect to O ^2-And F ^-Mol ratio (that is, the F of total content ^-/ (O ^2-+ F ^-)) be more than 0.05 and 0.25 following mode is set the composition of the described fluophosphate glass in the product glass stage, concoct frit based on the described composition that sets.

As described in above-mentioned [opinion 1]～[opinion 3], in the present embodiment, might not can substantially produce volatile matter (POF ₃).Owing to can substantially not produce volatile matter, can till the stage to the stage that obtains product glass through melting of blending frit, the main change reason of the composition in the glass be disappeared.Therefore, in order to obtain having the product glass of above-mentioned composition, as long as use the frit with same composition.

Therefore, in described frit, contain at least fluorine, oxygen, phosphorus, as long as the composition in the product glass stage satisfies above-mentioned condition, and further meet the following conditions and get final product.Namely, as long as be to concoct described frit and according to the mol ratio (F of the fluorine content F that contains in the described frit with respect to the total content of oxygen and fluorine more than 3.2 and less than 3.4 mode according to the oxygen level that contains in the described frit with respect to the mol ratio (O/P) (that is, raw material O/P ratio) of phosphorus content ^-/ (F+O)) (that is, raw material F ratio) is more than 0.05 and 0.25 following mode is concocted described frit and got final product.

Herein, as long as O ^2-/ P ⁵⁺Ratio and raw material O/P ratio are more than 3.2, just can in advance the P-O-P chain moderately be cut off, and therefore can fully suppress the generation of volatile matter with the frit melting time.In addition, can suppress the cut-out of the P-O-P chain that caused by water molecules, therefore can make product glass possess sufficient weathering resistance.

Further, 3.2 these numerical value are the O that obtained by [opinion 3] ^2-/ P ⁵⁺Than near the value of=3.3 these numerical value, therefore can substantially not produce volatile matter, moreover, also be to have more stable tripolyphosphate structure as structure, also increase as the stability of product glass.

Herein, as long as O ^2-/ P ⁵⁺Ratio and raw material O/P ratio are less than 3.4, then as [opinion 1] is described, even make product glass contain Cu in order to have desired near-infrared absorption ability ²⁺, also can suppress the visible absorption ability and excessively bring into play.In addition, also can suppress to add Cu this moment ²⁺The time color development.

On the other hand, as long as F ^-Ratio and raw material F ratio are more than 0.05, even hypothesis O ^2-/ P ⁵⁺Ratio and raw material O/P also can make F Jie of abundant amount be (or between tripolyphosphate structure) between the tetra-sodium structure than near 3.4 so larger values, can maintain the homogeneous structure after the P-O-P chain is cut off.Its result can fully suppress to be cut off and the crystallization that causes by the P-O-P chain, and then can make product glass possess sufficient weathering resistance.

In addition, as long as F ^-Than and raw material F ratio be below 0.25, as described in [opinion 2], in can the low temperature with the frit melting, can produce volatile matter at least not substantively.In addition, do not make oxygen too much with respect to the relative quantity of fluorine, therefore as a result of, can moderately keep higher O ^2-/ P ⁵⁺Ratio and raw material O/P ratio, and then can suppress substantially to produce volatile matter.Its result can disappear the main change reason of the composition in the glass till the stage to the stage that obtains product glass through melting of blending frit, can be to the O in the product glass ^2-/ P ⁵⁺Than controlling so that it has desired near-infrared absorption ability.

Above content is summarized, and the present invention is from being conceived at first and the O that forms more stable tripolyphosphate structure ^2-/ P ⁵⁺Than the value that=3.3 ([opinions 3]) approach, O ^2-/ P ⁵⁺Even appropriateness was added Cu when ratio was worth for this ²⁺Can taken in excess visible light ([opinion 1]) yet.And, have this value (O in order to make product glass ^2-/ P ⁵⁺Than) and make raw material F than (and F ^-Than) be above-mentioned scope, thus volatile matter can substantially do not produced, eliminate main component fluctuation reason ([opinion 2]).

As mentioned above, just because of there be [opinion 1]～[opinion 3], make O so could derive ^2-/ P ⁵⁺Than and raw material O/P ratio is more than 3.2 and less than 3.4, make simultaneously F ^-Than and raw material F than be more than 0.05 and 0.25 below such formation.That is, each numerical range itself also is significant, in the present embodiment, only has both numerical range competence exertions of combination to go out real value.Namely, be accommodated in simultaneously in both numerical ranges just because of glass is formed, can obtain to bring into play the fluophosphate glass of following multi-effect: can in fluophosphate glass, add " can absorb near infrared light " simultaneously Cu of the amount of " inhibition color development ", " suppressing visible Optical Absorption " degree ²⁺, " can begin O to setting like this from the frit stage ^2-/ P ⁵⁺Than controlling ", and " possessing weathering resistance ".

Need to prove, though at described later＜2. fluophosphate glass〉in be described in detail, can make the rare earth class ion content in the described fluophosphate glass is more than the 0.5 positively charged ion % and below the 2.0 positively charged ion % with respect to the ratio of whole cation constituent content.Thus, can allow to carry out the drop in temperature of melting, manufacturing process is simplified.Making the rare earth class ion content is in the situation of above-mentioned scope, and can make melt temperature is below 1000 ℃, therefore preferably in this temperature frit is carried out melting.

Below, unless otherwise specified, the content of cation constituent, total content represent with positively charged ion %; The content of anionic component represents or only represents with % with negatively charged ion %.

Need to prove, hereinbefore, narrate for the composition that product glass after frit and the manufacturing has, but the concrete operation such as the melting in the manufacture method of fluophosphate glass can be used the in the past employed method such as casting, conduit outflow, roller, pressurization.As the concrete example of this operation,＜4. other project in enumerated.

Yet, when using above-mentioned in the past method, the described composition that is preferably based on setting is concocted frit, and Exhaust Gas is also enclosed in closed system, with described frit melting, thereby can produce glass in that described mol ratio is produced in the situation of substantial change.If be present embodiment, then just can substantially not produce volatile matter from beginning, but in order to eliminate as much as possible the component fluctuation reason, then preferred by in can sealing the such encloses container of Exhaust Gas, described frit is carried out the melting cooling, and glass thus manufactures a product.

＜2. fluophosphate glass 〉

As mentioned above, the fluophosphate glass that is obtained by the aforesaid method manufacturing has and almost identical the forming of frit stage.As a result, the fluophosphate glass in the present embodiment is because containing Cu ²⁺And have the ability that absorbs near infrared light, simultaneously an O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) be more than 3.2 and less than 3.4, the F in the described fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) be more than 0.05 and below 0.25.

In addition, the fluophosphate glass of present embodiment particularly preferably is, and in the spectrophotometric transmittance of fluophosphate glass, for the thickness of the transmitance of demonstration 50% in the wavelength of 615nm, the transmitance of its wavelength 1200nm is less than 15%.Need to prove that should be derived by the following fact less than 15% this numerical value: the raw material F in Fig. 5 be than being that raw material O/P ratio is in 0.08 the plotting, and transmitance is less than 15% at 3.4 o'clock.

The composition of frit or product glass satisfies above-mentioned condition, thereby can obtain having in the near infrared light zone sufficient receptivity and and fluophosphate glass that visible light seen through suppressed in the receptivity of visible region.Only contrast the transmitance of the table 1 of the transmitance (table 2) of fluophosphate glass of present embodiment described later and patent documentation 12, just can know that the transmitance of present embodiment in the near infrared light zone drops to about half (that is, can absorb the near infrared light near 2 times).Obtain this result nothing more than being because can be met the fluophosphate glass of above-mentioned condition, and then can add and absorb the Cu of amount that near infrared light suppresses the degree of visible Optical Absorption simultaneously ²⁺

In addition, the rare earth class ion content in the fluophosphate glass is preferably more than the 0.5 positively charged ion % with respect to the ratio of the content of whole cation constituents and below the 2.0 positively charged ion %.

If the content as the contained rare earth class ion of cation constituent is described scope, then can moderately suppress melting temperature (Tm), liquidus temperature, the outflow temperature of melten glass and the rising of mold temperature of frit.In the present embodiment, by making O ^2-/ P ⁵⁺Ratio and raw material O/P ratio are (further to make F more than 3.2 and less than 3.4 ^-Than and raw material F ratio be more than 0.05 and 0.25 below), really can substantially suppress the generation of volatile matter, and guarantee the weathering resistance of product glass.Yet in addition, the rising that suppresses melting temperature (Tm), liquidus temperature, mold temperature can also further substantially suppress the generation of volatile matter, and guarantees the weathering resistance of product glass.

In addition, in the situation of the high glass of liquidus temperature, want reduce to flow out temperature or mold temperature, when then flowing out or the viscosity of the glass during moulding can uprise, from melten glass, be difficult to isolate fused glass block or melten glass and drip or be difficult to carry out moulding.

On the other hand, from can be not making glass coloring, can not making the viewpoint that improves specific refractory power in the situation that thermostability declines to a great extent, in fluophosphate glass, the situation that imports the rare earth class ion preferably import Y, La, Gd, Yb any or more than a kind.

Because of this reason, the total content that preferably makes described rare earth class ion is more than the 0.5 positively charged ion % and below the 2.0 positively charged ion %.In other words, preferably make and comprise Y ³⁺, La ³⁺, Gd ³⁺And Yb ³⁺Total content be that 0.5 positively charged ion % is above and below the 2.0 positively charged ion %.Wherein, Y in maintenance heat stability, simultaneously improve specific refractory power aspect effect excellent, therefore preferably make to comprise Y ³⁺Total content be that 0.5 positively charged ion % is above and below the 2.0 positively charged ion %.

And then, as an example, can enumerate following fluophosphate glass, the composition of described fluophosphate glass satisfies above-mentioned condition (O ^2-/ P ⁵⁺Ratio and raw material O/P ratio and F ^-The numerical range of ratio and raw material F ratio), wherein, represent the composition of the fluophosphate glass of present embodiment with positively charged ion %.

Can enumerate a kind of fluophosphate glass, it contains:

P

⁵⁺ 3%～50%、

Al ³⁺ 5%～40%、

Li

⁺ 0%～30%、

Na

⁺ 0%～20%、

K

⁺ 0%～20%、

Mg

²⁺ 0%～10%、

Ca ²⁺ 0%～30%、

Sr ²⁺ 0%～30%、

Ba

²⁺ 0%～40%、

Wherein, Mg ²⁺, Ca ²⁺, Sr ²⁺And Ba ²⁺Total amount be more than 10%, also to contain:

Zn ²⁺ 0%～20%、

In ²⁺ 0%～20%、

Y

³⁺ 0%～10%、

La

³⁺ 0%～10%、

Gd

³⁺ 0%～10%、

Yb

³⁺ 0%～10%、

Cu ²⁺ 0.5%～13%、

And % represents with negatively charged ion, also contains:

F

^- 20%～95%

O ^2- 5%～80%。

Below, describe for above-mentioned each composition.

P ⁵⁺It is the important component that in glass, plays a role as the network forming component.In addition, also be the O that determines the characteristic of present embodiment ^2-/ P ⁵⁺One of key element of ratio.Basically, as long as P ⁵⁺Amount be accommodated in above-mentioned O ^2-/ P ⁵⁺The scope of ratio gets final product, and when enumerating numerical value as an example, if be more than 3%, fluophosphate glass is stable.In addition, if below 50%, can obtain necessary low dispersiveness.Therefore, preferably make P ⁵⁺Content be 3%～50% scope.

Al ³⁺For the important component that improves stability in fluophosphate glass, if more than 5% then fluophosphate glass be stable.In addition, if below 40%, can guarantee the total amount of other composition, fluophosphate glass equally also is stable.Therefore, preferably make Al ³⁺Content be 5%～40% scope.

Such as Li ⁺, Na ⁺, K ⁺Such basic metal is that viscosity, the second-order transition temperature that can make glass descend, and makes the composition that carries out easy to manufacture of glass.Therefore, preferably make Li ⁺Amount be 0%～30%, Na ⁺Amount be 0%～20%, K ⁺Amount be 0%～20%.In basic metal, Li ⁺The effect of raising stability large, therefore more preferably import the Li more than 0.5% ⁺, further preferably import the Li more than 1% ⁺, particularly preferably import the Li more than 2% ⁺

Such as Mg ²⁺, Ca ²⁺, Sr ²⁺, Ba ²⁺Such alkaline-earth metal is the stability that improves glass, the composition that specific refractory power is risen, and is more than 10% by making its total amount, thereby can improves the effect for stability.Need to prove Mg ²⁺, Ca ²⁺It is the useful composition that the devitrification resistance that makes glass, weather resistance, processibility improve.Sr ²⁺, Ba ²⁺The devitrification resistance that makes glass, the useful composition that meltbility improves.

Yet, if specific alkaline-earth metal composition becomes too much, be damaged with the balance of other composition, therefore preferably equably importing preferably imports Mg ²⁺, Ca ²⁺, Sr ²⁺, Ba ²⁺Two or more at least compositions.The preferred content of each composition is: Mg ²⁺Be 0%～10%, Ca ²⁺Be 0%～30%, Sr ²⁺Be 0%～30%, Ba ²⁺Be 0%～40%.

Zn ²⁺, In ³⁺Similarly has the characteristic that can import easily in the glass with alkaline-earth metal, by importing Zn ²⁺Or In ³⁺Thereby making glass ingredient is Multiple components, can expect thus the raising effect of stability, but not preferred superfluous importing.Therefore, Zn ²⁺And In ³⁺Import volume be preferably respectively 0%～20%, particularly preferably do not import Zn ²⁺And In ³⁺

Y ³⁺, La ³⁺, Gd ³⁺, Yb ³⁺Be to keep the low dispersiveness of glass, improve the composition of specific refractory power simultaneously Deng rare earth element, melting temperature (Tm) rises, the stability decreases of glass but superfluous importing can make.Therefore, preferably make the amount of described each composition be respectively 0%～10%.

Need to prove, for present embodiment, in frit, add Cu ²⁺By adding Cu ²⁺, can give the near-infrared absorption characteristic to product glass.In the present embodiment, interpolation can fully absorb the Cu of amount of degree of the light near infrared light zone ²⁺, and, the Cu that adds ²⁺Amount also be the amount of light that can the taken in excess visible region.As mentioned above, this addition is by O ^2-/ P ⁵⁺Ratio and raw material O/P and F ^-Ratio and raw material F ratio decide.Wherein, when enumerating a numerical example, expectation is added 0.5%～13% Cu by the mode of outer interpolation ²⁺

Need to prove, contain Cu ²⁺Glass be suitable as the color correction filter material of the semiconductor camera elements such as CCD or CMOS.Cu ²⁺As long as addition consider the thickness of described strainer, suitably be specified in the described scope and get final product.

Next, anionic component, negatively charged ion additive are described.In the fluophosphate glass of present embodiment, F ^-And O ^2-It is the Main Anions composition.Basically, F ^-And O ^2-As long as amount be accommodated in above-mentioned F ^-The scope of ratio gets final product, and when enumerating an example of numerical value, from realizing the viewpoint of desired optical characteristics and the weathering resistance of excellence, preferably imports 20%～95% F ^-, 5%～80% O ^2-

In addition, by importing a small amount of Cl ^-, Br ^-, I ^-, then fluophosphate glass is difficult to invade profit to the platinum products such as employed platinum container or platinum nozzle processed when the glass manufacture or when flowing out.Therefore, can carry out easily the manufacturing of glass.Yet, Cl ^-, Br ^-, I ^-The surplus importing can cause the specific refractory power change that causes because of composition volatilization and the generation of platinum impurity, so import volume preferably adds up to 0%～3%, more preferably 0.1%～3%.

Need to prove that for the quality of the fluophosphate glass that improves present embodiment, expectation makes F ^-, O ^2-, Cl ^-, Br ^-And I ^-Total amount be more than 98%, more expectation is more than 99%, further expectation is 100%.

Need to prove, in the present embodiment, do not contain B ³⁺Originally, B ³⁺Be the composition that improves the weather resistance of glass, but it have the tendency that forms fluorochemical and volatilize when frit being melted.Therefore, do not contain B in the fluophosphate glass of present embodiment ³⁺

Also there are some and B ³⁺Same, preferably do not contain the composition in the fluophosphate glass of present embodiment.Specifically, consider the load to environment, preferably do not contain any of Pb, As, Cd, Cr, U, Th, Tl and ion thereof and compound.Need to prove, do not contain at least Pb and Tl in the fluophosphate glass of present embodiment.

＜3. by the embodiment produce an effect 〉

Played following effect by present embodiment.

That is, can access the fluophosphate glass of the following multi-effect of performance: can in fluophosphate glass, add " absorption near infrared light " simultaneously Cu of the amount of " inhibition color development ", " suppressing visible Optical Absorption " degree ²⁺, " can begin O to setting like this from the frit stage ^2-/ P ⁵⁺Than controlling ", and " making it possess weathering resistance ".

Its result can provide fluophosphate glass and manufacture method thereof, even described fluophosphate glass also has following O after manufacturing ^2-/ P ⁵⁺Ratio, and possess weathering resistance, described O ^2-/ P ⁵⁺Than being to absorb the Cu of amount that near infrared light suppresses the degree of visible Optical Absorption simultaneously according to adding ²⁺Mode set.

Further, by making Cu ²⁺Glass ingredient amount in addition changes Cu simultaneously than for constant ²⁺Content, can have both " near infrared Optical Absorption " and " visible Optical Absorption suppress ".Therefore, by making Cu ²⁺Glass ingredient amount is in addition adjusted Cu simultaneously than for constant ²⁺Content, can adjust the thickness of strainer.By increasing Cu ²⁺Content, can make the thickness attenuation of strainer; By reducing Cu ²⁺Content, can make the thickness thickening of strainer.That is, according to the present invention, can provide a kind of Cu ²⁺In addition glass ingredient amount is than for constant, and the glass material of strainer that can corresponding various thickness.

Use Cu ²⁺Glass ingredient amount in addition is than identical and Cu ²⁺The different glass of content make in the situation of strainer, it is almost identical that glass forms, and also can not carry out good moulding, processing even therefore do not change condition of molding, the processing conditions of glass.

＜4. other

Below, the concrete example of the operations such as melting in the manufacture method of fluophosphate glass is narrated.At this moment, as an example, below narrate for the example of being made the near-infrared absorption strainer by the frit that satisfies above-mentioned prerequisite.

In addition, except above-mentioned embodiment, also narrate for the situation of applicable [opinion 1]～[opinion 3].

(concrete example of the manufacture method of fluophosphate glass)

At first, the frit of above-mentioned prerequisite is satisfied in weighing, after mixing, heats in thermotolerance crucible, for example platinum or platinum alloy crucible processed, melting.Need to prove, in the present embodiment, can substantially not produce volatile matter, but hypothesis produces a small amount of volatile matter, expectation is covered the heat-resisting lids such as platinum on crucible in order to suppress volatilization.

And, glass to molten state stirs, clarifies, flowed out with nozzle by glass the glass melt of bubbles not and homogeneous is flowed out, thereby carry out moulding, it is that platinum system, platinum alloy system, gold are made, any nozzle of au-alloy system that described glass flows out with nozzle.

When glass flows out, because of Cl contained in the glass melt ^-, Br ^-, I ^-The glass melt that flowed out by the nozzle tip of at least a above halogen composition and can being inhibited invade the effect of the phenomenon of profit (moisten れ and go up the Ga Ru) from spray nozzle front end to the nozzle periphery.Its result, can reduce, prevent following phenomenon: the glass melt of invading profit is rotten, and is blended into afterwards on the turn in the melten glass of outflow, produces the shortcomings such as brush line or devitrification.

Yet, for the near-infrared absorption strainer, in order to consist of the compact type camera system that possesses semiconductor image sensor, require to improve the function of shielding of near infrared light, keep the transmitance of higher visible light simultaneously.From such viewpoint, preferably, be the glass of 50% thickness for the outside transmitance in wavelength 615nm, it is the light of absorbing wavelength 500nm substantially not at least.Need to prove, herein said " substantially " comprise and do not absorb all light of these wavelength, also comprise light that hypothesis absorbed this wavelength and also be the situation of the absorption of the level that in practical application, can not have problems.

In addition, preferably the outside transmitance in wavelength 400nm is more than 80%.About the near infrared Optical Absorption, the transmitance in wavelength 1200nm is preferably less than 15%.

The making of described near-infrared absorption strainer is for example lower.

At first, in order to obtain described glass, the melten glass after clarifying, homogenizing is melted, it is flowed out from conduit, flow in the mold, be shaped to the thicker large glass block of thickness of slab.For example, prepare mold, melten glass after will homogenizing with constant take-off rate is poured in this mold by the conduit of platinum alloy system, described mold by the bottom surface of smooth and level, clip this bottom surface each other parallel subtend pair of sidewalls, be positioned at the weir plate that the peristome of the side between pair of sidewalls is plugged and consist of.The melten glass of casting is at the mold internal diffusion, and is defined as certain width by pair of sidewalls, is shaped to thus plate glass.Plate glass after the moulding is drawn out of continuously by the peristome of mold.Herein, the conditions of molding such as take-off rate of the shape by suitable setting mold, size, melten glass, can moulding the glass block of large and wall thickness.

Need to prove that the melting of frit can be carried out, and also can carry out under atmosphere under the atmosphere of the rare gas elementes such as nitrogen or dry air.According to the present invention, can under the condition that not affected by glass melting atmosphere, carry out manufacturing, the supply of high-quality fluophosphate glass.

Glass block after the moulding is transferred to and is heated in advance near the annealing furnace of second-order transition temperature, is cooled to gradually room temperature.For by cooling off gradually the glass block of having removed distortion, implement high-precision section, grinding, attrition process, thereby must arrive the sheet glass that optical grinding has been carried out on the two sides.This sheet glass can be used as the near-infrared absorption strainer, but also can fit to make the near-infrared absorption strainer to described sheet glass.The tabular crystal that optical grinding has all been carried out on the two sides fits in the two sides has been carried out on the one side of tabular near-infrared absorption glass of optical grinding.Then, fit at face of crystal and visible light is seen through and tabular opticglass, for example BK-7 (borosilicate optical glass) of optical grinding have all been carried out in the two sides.Can consist of the near-infrared absorption strainer by this structure, but also can be on a face of described slab glass, another sheet of fitting can make visible light see through and the tabular opticglass (for example BK-7) of optical grinding has all been carried out on the two sides.As required, form optical multilayer on the surface of strainer.

So far, be illustrated for the situation that glass block is processed as sheet glass, but also can be by glass block being carried out grinding, grinding and make lens or be processed as other shape.

The near-infrared absorption glass of present embodiment is fluophosphate glass, its second-order transition temperature is low, therefore after carrying out moulding by precise compression molding (mould molding), needn't implement the mechanical workouts such as grinding or grinding to the photosensitiveness functional surfaces and just can form the optical elements such as lens, diffraction grating.For example; with high precision the molding surface of the known compression molding section bars such as SiC, superhard material is processed as shape with the lens face counter-rotating of non-spherical lens; thereby making upper die and lower die; use this upper and lower mould or known phantom as required or upper and lower mould guide member, the glass preform that the near-infrared absorption glass by present embodiment is consisted of heats, precise compression molding.So, molding surface critically can be transferred to glass, make non-spherical lens.This non-spherical lens also is the near-infrared absorption strainer of present embodiment.The non-spherical lens that so obtains can consist of part or all of optical system that is used for subject is imaged in sensitive surface of semiconductor image sensor, can reduce the optics number of packages in the camera head, and also be effective for save space, cost degradation.

With high precision the molding surface of compression molding section bar is processed as shape with the diffraction grating counter-rotating, thereby making upper die and lower die, and the same method of employing and described method carries out precise compression molding to glass preform, can make thus the near-infrared absorption strainer that possesses diffraction grating.

The near-infrared absorption strainer that possesses diffraction grating can be used as the optical low-pass filter of the light that is incident to semiconductor image sensor and brings into play function.Therefore, near-infrared absorption strainer and optical low-pass filter can be made as an element, therefore can reduce the optics number of packages in the camera head, can carry out save space, cost degradation simultaneously.

Need to prove, if making the molding surface of compression molding section bar is the shape of lens face (for example lens face of non-spherical lens) counter-rotating, and be processed as the shape with the ditch counter-rotating of diffraction grating, adopt with the same method of described method and carry out precise compression molding, then can make and have both near-infrared absorption function, optical functions of low-pass filter and the near-infrared absorption strainer of lens function.

As required, can form known antiadhesion barrier on the molding surface of compression molding section bar.In addition, each condition of precise compression molding can be suitable for known condition, can suitably determine according to the concrete specification as the near-infrared absorption strainer of target simultaneously.

So make the near-infrared absorption strainer by precise compression molding, thereby can be unsuitable for based on higher productivity manufacturing the element based on the volume production of grinding, grinding, such as the non-spherical lens with diffraction grating of non-spherical lens, the optical low-pass filter that possesses diffraction grating, performance optical low-pass filter function etc.Need to prove, as required, on the surface of near-infrared absorption strainer, can form the optical multilayers such as antireflection film.

According to the near-infrared absorption strainer of present embodiment, the transmitance of visible light is high, the near infrared Optical Absorption is large, therefore can carry out well the response colour relation of semiconductor camera element and proofread and correct.And can make the high strainer of optics uniformity.

In addition, by with the near-infrared absorption strainer of present embodiment and semiconductor image sensor combination and can be applicable to camera head.Need to prove, in the semiconductor image sensor, the semiconductor camera elements such as CCD or CMOS are installed in the package, and utilize transparent member that light-receiving part is covered.Can be double as transparent member take the near-infrared absorption strainer, also can make transparent member and near-infrared absorption strainer is different parts.

Need to prove that the camera head of above-mentioned present embodiment also can possess for the picture with subject and images in the optical elements such as lens on the sensitive surface of semiconductor image sensor or prism.

In addition, according to above-mentioned camera head, carry optics uniformity excellence, the transmitance height of visibility region, the regional large near-infrared absorption strainer of absorption of near infrared light, therefore can provide response colour relation to proofread and correct camera head good, that can access the image of image quality excellence.

Need to prove, if be present embodiment, even then also can make for the optical element (lens etc.) outside the near-infrared absorption strainer.In addition, in order to be applied to the product of various glass systems, also can carry out various distortion.

(Application Example of [opinion 1]～[opinion 3])

In the present embodiment, for because containing Cu ²⁺And the fluophosphate glass that can absorb near infrared light is narrated.Yet, with Cu ²⁺Near-infrared absorption composition in addition (compounds such as the Al that has enumerated or In, Sn, W or their oxide compound etc.) replaces Cu ²⁺, or add simultaneously, even in this case also applicable the present invention.That is, when adding certain near-infrared absorption composition, that works that optical absorption peak is divided into 2 such as [opinion 1], if its optical absorption peak is because of O ^2-/ P ⁵⁺Than and be affected, the possibility that above-mentioned problem then occurs is high.In addition, [opinion 2] or [opinion 3] is and O ^2-/ P ⁵⁺Ratio and F ^-Than relevant content, even therefore for adding Cu ²⁺The situation of composition in addition, the possibility that can be suitable for are also very high.For the mode of reflection foregoing, remarks is in the end of specification sheets.

In addition, even O ^2-/ P ⁵⁺Ratio and raw material O/P ratio and F ^-Ratio and raw material F deviate from the described numerical range of present embodiment than a little, also might can play above-mentioned effect.For the mode of reflection foregoing, remarks is in the end of specification sheets.

[embodiment]

Then, embodiment is shown, the present invention is carried out specific description.The present invention is not limited to following embodiment certainly.

＜embodiment 1～44 〉

For each glass that can access the embodiment 1～44 shown in the table 2 forms, to phosphoric acid salt such as bisphosphate zinc, concoct with such raw materials of fluorochemical such as Sodium Fluorides, drop in the platinum crucible, at embodiment 1～11, in 16～41 with 1000 ℃ melt temperature, in embodiment 12 with 900 ℃ melt temperature, in embodiment 42～44 with 950 ℃ melt temperature, utilize raw material was heated in 2～3 hours while stirring, melt, clarification, homogenize, after obtaining the glass melt of homogeneous, with glass melt, be that melten glass is poured in the mold, thereby obtain being equivalent to 44 kinds of fluophosphate glasses of embodiment 1～44.Need to prove, in described operation, be not difficult to carry out glass manufacture because of a large amount of volatile components that produce.In addition, in the inside of the glass that obtains, do not confirm separating out or residual bubble, impurity, brush line of crystallization.

Table 2

* among the embodiment 42, λ 50=582nm; Among the embodiment 43, λ 50=569nm; Among the embodiment 44, λ 50=561nm; In the comparative example 3, λ 50=665nm

＜comparative example 1～3 〉

With respect to embodiment 1～44, in comparative example 1～2, make raw material O/P than (being the O in the product glass ^2-/ P ⁵⁺Than) be the glass of the comparative example more than 3.4.In addition, in comparative example 3, make Cu ²⁺Be 1.00% of minute quantity.In addition composition is as shown in table 2, and is identical with embodiment as concrete manufacturing process.

＜reference example 1～10 〉

Need to prove, for the outer O of the numerical range with present embodiment ^2-/ P ⁵⁺Than but also can in the near infrared light zone, reduce the example of transmitance, illustrate with the form of reference example.

Specifically, as a reference example 1～7, make raw material O/P than (being the O in the product glass ^2-/ P ⁵⁺Ratio) glass less than 3.2.In addition composition is as shown in table 2, and to make melt temperature in the reference example 1～5 be that to make melt temperature in 1000 ℃, reference example 6～7 be 900 ℃, and concrete manufacturing process in addition is identical with embodiment.

In addition, as a reference example 8～10, make raw material F than (being the F in the product glass ^-Ratio) glass less than 0.05.In addition composition and concrete manufacturing process are as shown in table 2.Composition outside this is as shown in table 2, and identical with embodiment as concrete manufacturing process.

＜transmitance 〉

For each glass of embodiment 1～44, comparative example 1～3 and reference example 1～10, the outside transmitance among the wavelength 615nm is 50% thickness, is shown in table 2 based on the outside transmitance among the wavelength 1200nm of this thickness (also showing transmitance among wavelength 400nm, the 500nm for some embodiment).

As shown in table 2, in the glass of embodiment, the transmitance of visibility region is high, and in embodiment and reference example, the function of shielding of near infrared light is excellent, is suitable as the chromatic aberration correction of semiconductor image sensor with strainer glass.

On the other hand, the transmitance of the glass of comparative example is more than 15%, compares with reference example with embodiment, a little less than the Optical Absorption ability for the near infrared light zone.Need to prove, in the glass of comparative example 3, Cu ²⁺Being minute quantity, therefore can't absorbing near infrared light, is not because containing Cu just originally ²⁺And can absorb the fluophosphate glass of near infrared light.Therefore, although the glass of comparative example 3 has the interior O of numerical range of present embodiment ^2-/ P ⁵⁺Ratio and F ^-Ratio, but still belong to comparative example.On the contrary, in the fluophosphate glass of present embodiment, Cu ²⁺Containing ratio preferably surpass 1.00%.In addition, if consider embodiment 1～44, then Cu ²⁺Containing ratio more preferably surpass 2.50%.On the other hand, from the viewpoint of the thermostability of keeping glass, Cu ²⁺Containing ratio be preferably below 5%.

Below, remarks has other preferred mode.

[remarks 1]

A kind of fluophosphate glass, it is because containing Cu ²⁺And have the fluophosphate glass of optical absorption peak in the near infrared light zone, it is characterized in that,

Described peak energy enough freely is separated into 2 peaks, Cu ²⁺Can color development, the substantially light of absorbing wavelength 1200nm and the not light of absorbing wavelength 500nm substantially;

F in the described fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) scope of value substantially do not produce POF when making described near-infrared absorption strainer ₃The value of degree as the upper limit.

[remarks 2]

A kind of fluophosphate glass, it is because containing Cu ²⁺And can absorb the fluophosphate glass of near infrared light, it is characterized in that,

O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) O ^2-/ P ⁵⁺The scope of ratio can substantially not produce POF when making described near-infrared absorption strainer ₃The O of degree ^2-/ P ⁵⁺Than being lower limit, with Cu ²⁺Can color development, can drop into the light of absorbing wavelength 1200nm substantially and the Cu of the amount of the degree of the light of absorbing wavelength 500nm substantially not ²⁺O ^2-/ P ⁵⁺Ratio is the upper limit,

[remarks 3]

O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) be more than 3.05 and less than 3.40,

F in the described fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) be more than 0.03 and below 0.19.

[remarks 4]

A kind of fluophosphate glass is characterized in that, described F ^-The ratio of content is not to produce by P ₂O ₇ ^4-And the value of the degree of the crystallization that causes is lower limit.

[remarks 5]

A kind of manufacture method of fluophosphate glass, it is by frit is concocted, and described frit is carried out melting, thereby makes because containing Cu ²⁺And can absorb the method for the fluophosphate glass of near infrared light, it is characterized in that, in the described fluophosphate glass as O ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) O ^2-/ P ⁵⁺The scope of ratio will can substantially not produce POF when making described near-infrared absorption strainer ₃The O of degree ^2-/ P ⁵⁺Be compared to lower limit, on the other hand, with Cu ²⁺Can color development, can drop into the light of absorbing wavelength 1200nm substantially, the Cu of the amount of the degree of the light of absorbing wavelength 500nm substantially not simultaneously ²⁺O ^2-/ P ⁵⁺Than being set as the upper limit,

F in the described fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) scope of value substantially do not produce POF in the time of will making described near-infrared absorption strainer ₃The value of degree be set as the upper limit,

Based on the described composition of setting frit is concocted, made thus glass.

[remarks 6]

A kind of manufacture method of fluophosphate glass, it is by frit is concocted, and described frit is carried out melting, thereby makes because containing Cu ²⁺And can absorb the method for the fluophosphate glass of near infrared light, it is characterized in that,

In the described fluophosphate glass as O ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) O ^2-/ P ⁵⁺The scope of ratio can substantially not produce POF when making described near-infrared absorption strainer ₃The O of degree ^2-/ P ⁵⁺Than being lower limit, with Cu ²⁺Can color development, can drop into the light of absorbing wavelength 1200nm substantially, the Cu of the amount of the degree of the light of absorbing wavelength 500nm substantially not simultaneously ²⁺O ^2-/ P ⁵⁺Ratio is the upper limit,

Based on the described composition of setting frit is concocted, and Exhaust Gas is enclosed in the enclosed system, with described frit melting, thereby produce glass in that described mol ratio is produced in the situation of substantial change.

[remarks 7]

A kind of fluophosphate glass, it is the fluophosphate glass that can absorb near infrared light because containing the near-infrared absorption composition, it is characterized in that, in the described fluophosphate glass as O ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) O ^2-/ P ⁵⁺The scope of ratio can substantially not produce POF when making described fluophosphate glass ₃The O of degree ^2-/ P ⁵⁺Than for lower limit, on the other hand, with the near-infrared absorption composition can color development, can drop into the light of absorbing wavelength 1200nm substantially, the Cu of the amount of the degree of the light of absorbing wavelength 500nm substantially not simultaneously ²⁺O ^2-/ P ⁵⁺Ratio is the upper limit,

F in the described fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) scope of value substantially do not produce POF when making described near-infrared absorption strainer ₃The value of degree be the upper limit.

Claims

1. fluophosphate glass, it is because containing Cu ²⁺And can absorb the fluophosphate glass of near infrared light, it is characterized in that,

O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) be more than 3.2 and less than 3.4,

F in the described fluophosphate glass ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) be more than 0.05 and below 0.25,

2. fluophosphate glass as claimed in claim 1 is characterized in that, the rare earth class ion content in the described fluophosphate glass is more than the 0.5 positively charged ion % and below the 2.0 positively charged ion % with respect to the ratio of the content of whole cation constituents.

3. fluophosphate glass as claimed in claim 1 or 2 is characterized in that, in the spectrophotometric transmittance of fluophosphate glass, for the thickness that demonstrates 50% transmitance in wavelength 615nm, the transmitance of its wavelength 1200nm is less than 15%.

4. a near-infrared absorption strainer is characterized in that, this near-infrared absorption strainer has used each described described fluophosphate glass of claim 1～3.

5. the manufacture method of a fluophosphate glass, it is because containing Cu ²⁺And can absorb the method for the fluophosphate glass of near infrared light, and described fluophosphate glass is by frit is concocted, and described frit is carried out melting make, described manufacture method is characterised in that,

The composition of described fluophosphate glass is set as O in the described fluophosphate glass ^2-Content is with respect to P ⁵⁺Mol ratio (the O of content ^2-/ P ⁵⁺) be more than 3.2 and less than 3.4 and described fluophosphate glass in F ^-Content is with respect to O ^2-And F ^-The mol ratio (F of total content ^-/ (O ^2-+ F ^-)) be more than 0.05 and below 0.25, based on the described composition of setting frit is concocted, produce thus glass,

6. the manufacture method of fluophosphate glass as claimed in claim 5 is characterized in that,

Described frit contains fluorine, oxygen, phosphorus at least,

Be more than 3.2 and less than 3.4 mode described frit to be concocted according to the content of oxygen contained in the described frit with respect to the mol ratio of the content of phosphorus, and be more than 0.05 with respect to the mol ratio of the total content of oxygen and fluorine and 0.25 following mode is concocted described frit according to the fluorine content in the described frit, produce thus glass.

7. such as the manufacture method of claim 5 or 6 described fluophosphate glasses, it is characterized in that, making the rare earth class ion content in the described fluophosphate glass is more than the 0.5 positively charged ion % and below the 2.0 positively charged ion % with respect to the ratio of the content of whole cation constituents, and making melt temperature is below 1000 ℃.

8. such as the manufacture method of each described fluophosphate glass of claim 5～7, it is characterized in that in the spectrophotometric transmittance of fluophosphate glass, for the thickness that demonstrates 50% transmitance in wavelength 615nm, the transmitance of its wavelength 1200nm is less than 15%.