JP4589155B2 - Hard coat composition - Google Patents

Description

  The present invention relates to a hard coat composition. This is particularly suitable for an optical element formed of an organic glass having a high refractive index. Here, the “optical element” is a concept including a lighting fixture cover, a reflecting mirror, a prism, and a filter in addition to optical components such as a spectacle lens and a camera lens.

  Hereinafter, the description will be given mainly using the spectacle lens as an example, but the present invention is not limited thereto.

  Organic glass used as an optical lens has been widely used because it has advantages such as light weight, impact resistance, dyeability and easy processing as compared with conventional inorganic glass.

  However, in the state of organic glass, it has a drawback that it has low wear resistance and is easily scratched as compared with inorganic glass. On the other hand, a silicone-based hard coat film (cured coating film) is generally applied to the surface of an optical substrate made of organic glass for the purpose of improving wear resistance.

  The applicant of the present application has previously proposed a dyeable coating composition comprising an epoxy group-containing silane compound, a carboxylic acid, and a curing agent, and has partially put it into practical use (Patent Document 1).

  On the other hand, a spectacle lens made of organic glass has a low refractive index when compared to that of inorganic glass, and when used for an optical lens, the lens end face becomes thick and is not suitable for correcting visual acuity.

  However, in recent years, even organic glass having a refractive index of 1.60 or more has been put on the market due to technological innovation, and currently occupies 60% on the market scale and tends to increase in the future.

  With respect to such organic glass having a high refractive index, the applicant of the present application has proposed and partially put into practical use a coating composition (hard coat composition) for optical plastic molded articles having a high refractive index (Patent Document 2). .

  In recent years, the fashionability of eyeglasses has become more important, and it has become necessary to support a wider variety of coloring lenses. On the other hand, an organic glass lens having a high refractive index does not have good colorability (coloring speed).

  The coating composition described in Patent Document 2 has an excellent property of suppressing light interference between a coating film and an organic glass having a refractive index of 1.60 or less.

  However, when a spectacle lens to which the hard coat composition is applied is used for a long period of time, the iron oxide portion in the iron oxide / titanium oxide composite oxide fine particles used as the coating film component is blackened by ultraviolet rays, resulting in a beautiful appearance. The present inventors have found that it is impaired.

In addition, the present inventors also note that when exposed to ultraviolet rays due to the photocatalytic action of titanium oxide in the iron oxide / titanium oxide composite oxide fine particles, the hard coat layer is deteriorated or discolored or discolored. I found out.
Japanese Examined Patent Publication No. 57-42665 (refer to claims) Japanese Patent No. 2577670 (refer to claims etc.)

  In view of the above, the present invention can suppress the blackening phenomenon with respect to ultraviolet rays while maintaining the characteristic of suppressing the light interference of the hard coat with respect to the high refractive lens, and at the same time, the color lens can be discolored and decolored (fading). It is an object (problem) to provide a hard coat composition that can be suppressed and that does not impair the aesthetics even when used for a long period of time.

  In order to solve the above-mentioned problems (objectives), the present invention has come up with a hard coat composition having the following constitution as a result of diligent development efforts.

An alkoxysilane hydrolyzate and fine particles of niobium pentoxide (Nb ₂ O ₅ : hereinafter simply referred to as “niobium oxide”) are dispersed in a colloidal state.

  Since it does not contain titanium oxide having a photocatalytic action, it is not easily affected by light such as ultraviolet rays, and as a result, there is no occurrence of discoloration or discoloration as well as blackening as compared with the conventional example. In addition, niobium oxide fine particles can be applied to high refractive index organic glass as well as titanium oxide composite fine particles.

  In the above configuration, the composition of the alkoxysilane compound is desirably the following configuration.

Component (A):
General formula

で示されるトリアルコキシシランの加水分解物、及び
（但しＲ１はＨ又はＣＨ₃、Ｒ２は炭素数１〜４のアルキレン基、Ｒ３は炭素数１〜４のアルキル基で表される）
(Ｂ)一般式
Ｓｉ（ＯＲ１）₄で示されるテトラアルコキシシランの加水分解物、
（ 但しＲ１は炭素数１〜４のアルキル基で表される）
の混合物であって、前記（Ａ）成分／（Ｂ）成分＝７．５／２．５〜９．５／０．５の混合比率を有する。

And a hydrolyzate of trialkoxysilane represented by: (wherein R1 is H or CH ₃ , R2 is an alkylene group having 1 to 4 carbon atoms, and R3 is an alkyl group having 1 to 4 carbon atoms)
(B) a hydrolyzate of tetraalkoxysilane represented by the general formula Si (OR1) ₄ ;
(However, R1 is represented by an alkyl group having 1 to 4 carbon atoms)
The mixture (A) / component (B) = 7.5 / 2.5 to 9.5 / 0.5.

  In the above configuration, it is desirable that the niobium oxide colloid has a colloid particle size of 1 to 50 nm and an anionic surfactant as a dispersant.

  Here, the mixing ratio of the niobium oxide to 100 parts by mass of the anionic surfactant is preferably 10 to 100 parts by mass.

  The mixing ratio of niobium oxide to 100 parts by mass of alkoxysilane is preferably 40 to 100 parts by mass.

  The configuration of the optical element using the hard coat composition of each configuration described above is as follows.

  An optical element comprising a hard coat film formed of any one of the above-described hard coat compositions on one or both sides of an optical substrate formed of an organic glass having a refractive index of 1.60 or more.

  In the optical element, examples of the organic glass include a polythiourethane resin having a refractive index of 1.60 to 1.67.

  As the optical element, a primer film is further provided between the optical substrate and the hard coat film, and further, an optical inorganic thin film is further provided on the surface side of the hard coat film. Is desirable.

Detailed description of the configuration

  Hereinafter, the configuration of the present invention will be described in detail. In the following description, blending units, mixing ratios, and the like are based on “mass” unless otherwise specified.

  The hard coat composition of the present invention basically comprises (A) component / (B) component = (A) component which is a trialkoxysilane exemplified below and (B) component which is tetraalkoxysilane = Silicone having a mixing ratio of 7.5 / 2.5 to 9.5 / 0.5, preferably 8/2 to 9/1 is used as a matrix. If the mixing ratio is deviated, it is difficult to obtain sufficient coating film hardness and good appearance. That is, when the amount of tetraalkoxysilane is excessive, poor appearance due to cracks occurs at the time of thermal polymerization after the organic lens coating film, and when it is too small, it is difficult to obtain a sufficient coating film hardness.

（但し、Ｒ１はＨ又はＣＨ₃、Ｒ２は炭素数１〜４のアルキレン基、Ｒ３は炭素数１〜４のアルキル基で表される。）で示されるものであり、具体的には、
グリシドキシメチルトリメトキシシラン，グリシドキシメチルトリエトキシシラン，グリシドキシメチルトリプロポキシシラン，グリシドキシメチルトリブトキシシラン，αグリシドキシエチルトリメトキシシラン，αグリシドキシエチルトリエトキシシラン，αグリシドキシエチルトリプロポキシシラン，αグリシドキシエチルトリブトキシシラン，βグリシドキシエチルトリメトキシシラン，βグリシドキシエチルトリエトキシシラン，βグリシドキシエチルトリプロポキシシラン，βグリシドキシエチルトリブトキシシラン，αグリシドキシプロピルトリメトキシシラン，αグリシドキシプロピルトリエトキシシラン，αグリシドキシプロピルトリプロポキシシラン，αグリシドキシプロピルトリブトキシシラン，βグリシドキシプロピルトリメトキシシラン，βグリシドキシプロピルトリエトキシシラン，βグリシドキシプロピルトリプロポキシシラン，βグリシドキシプロピルトリブトキシシラン，γグリシドキシプロピルトリメトキシシラン，γグリシドキシプロピルトリエトキシシラン，γグリシドキシプロピルトリプロポキシシラン，γグリシドキシプロピルトリブトキシシラン，αグリシドキシブチルトリメトキシシラン，αグリシドキシブチルトリエトキシシラン，αグリシドキシブチルトリプロポキシシラン，αグリシドキシブチルトリブトキシシラン，βグリシドキシブチルトリメトキシシラン，βグリシドキシブチルトリエトキシシラン，βグリシドキシブチルトリプロポキシシラン，βグリシドキシブチルトリブトキシシラン，γグリシドキシブチルトリメトキシシラン，γグリシドキシブチルトリエトキシシラン，γグリシドキシブチルトリプロポキシシラン，γグリシドキシブチルトリブトキシシラン，δグリシドキシブチルトリメトキシシラン，δグリシドキシブチルトリエトキシシラン，δグリシドキシブチルトリプロポキシシラン，δグリシドキシブチルトリブトキシシラン，βメチルグリシドキシメチルトリメトキシシラン，βメチルグリシドキシメチルトリエトキシシラン，βメチルグリシドキシメチルトリプロポキシシラン，βメチルグリシドキシメチルトリブトキシシラン，βメチルαグリシドキシエチルトリメトキシシラン，βメチルαグリシドキシエチルトリエトキシシラン，βメチルαグリシドキシエチルトリプロポキシシラン，βメチルαグリシドキシエチルトリブトキシシラン，βメチルβグリシドキシエチルトリメトキシシラン，βメチルβグリシドキシエチルトリエトキシシラン，βメチルβグリシドキシエチルトリプロポキシシラン，βメチルβグリシドキシエチルトリブトキシシラン，βメチルαグリシドキシプロピルトリメトキシシラン，βメチルαグリシドキシプロピルトリエトキシシラン，βメチルαグリシドキシプロピルトリプロポキシシラン，βメチルαグリシドキシプロピルトリブトキシシラン，βメチルβグリシドキシプロピルトリメトキシシラン，βメチルβグリシドキシプロピルトリエトキシシラン，βメチルβグリシドキシプロピルトリプロポキシシラン，βメチルβグリシドキシプロピルトリブトキシシラン，βメチルγグリシドキシプロピルトリメトキシシラン，βメチルγグリシドキシプロピルトリエトキシシラン，βメチルγグリシドキシプロピルトリプロポキシシラン，βメチルγグリシドキシプロピルトリブトキシシラン，βメチルαグリシドキシブチルトリメトキシシラン，βメチルαグリシドキシブチルトリエトキシシラン，βメチルαグリシドキシブチルトリプロポキシシラン，βメチルαグリシドキシブチルトリブトキシシラン，βメチルβグリシドキシブチルトリメトキシシラン，βメチルβグリシドキシブチルトリエトキシシラン，βメチルβグリシドキシブチルトリプロポキシシラン，βメチルβグリシドキシブチルトリブトキシシラン，βメチルγグリシドキシブチルトリメトキシシラン，βメチルγグリシドキシブチルトリエトキシシラン，βメチルγグリシドキシブチルトリプロポキシシラン，βメチルγグリシドキシブチルトリブトキシシラン，βメチルδグリシドキシブチルトリメトキシシラン，βメチルδグリシドキシブチルトリエトキシシラン，βメチルδグリシドキシブチルトリプロポキシシラン，βメチルδグリシドキシブチルトリブトキシシラン等。これらは単独でも又２種以上併用することも可能である。 Component (A): trialkoxysilane Basically,

Where R1 is H or CH ₃ , R2 is an alkylene group having 1 to 4 carbon atoms, and R3 is an alkyl group having 1 to 4 carbon atoms. Specifically,
Glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, glycidoxymethyltripropoxysilane, glycidoxymethyltributoxysilane, α-glycidoxyethyltrimethoxysilane, α-glycidoxyethyltriethoxysilane, α-glycidoxyethyl tripropoxysilane, α-glycidoxyethyl tributoxysilane, β-glycidoxyethyltrimethoxysilane, β-glycidoxyethyltriethoxysilane, β-glycidoxyethyltripropoxysilane, β-glycidoxyethyl Tributoxysilane, α-glycidoxypropyltrimethoxysilane, α-glycidoxypropyltriethoxysilane, α-glycidoxypropyltripropoxysilane, α-glycidoxypropyltributoxysilane, β-glycidoxypropyltri Toxisilane, β-glycidoxypropyltriethoxysilane, β-glycidoxypropyltripropoxysilane, β-glycidoxypropyltributoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycid Xylpropyltripropoxysilane, γ-glycidoxypropyltributoxysilane, α-glycidoxybutyltrimethoxysilane, α-glycidoxybutyltriethoxysilane, α-glycidoxybutyltripropoxysilane, α-glycidoxybutyltributoxysilane Β-glycidoxybutyltrimethoxysilane, β-glycidoxybutyltriethoxysilane, β-glycidoxybutyltripropoxysilane, β-glycidoxybutyltributoxysilane, γ-glycidoxybutyltrimethoxysilane, Glycidoxybutyltriethoxysilane, γ-glycidoxybutyltripropoxysilane, γ-glycidoxybutyltributoxysilane, δ-glycidoxybutyltrimethoxysilane, δ-glycidoxybutyltriethoxysilane, δ-glycidoxybutyltri Propoxy silane, δ glycidoxy butyl tributoxy silane, β methyl glycidoxymethyl trimethoxy silane, β methyl glycidoxymethyl triethoxy silane, β methyl glycidoxymethyl tripropoxy silane, β methyl glycidoxymethyl tributoxy Silane, β-methyl α-glycidoxyethyl trimethoxysilane, β-methyl α-glycidoxyethyl triethoxysilane, β-methyl α-glycidoxyethyl tripropoxysilane, β-methyl α-glycidoxyethyl tributoxysilane, β-methyl β-glyci Xylethyltrimethoxysilane, βmethylβglycidoxyethyltriethoxysilane, βmethylβglycidoxyethyltripropoxysilane, βmethylβglycidoxyethyltributoxysilane, βmethylαglycidoxypropyltrimethoxysilane, β-methyl α-glycidoxypropyl triethoxysilane, β-methyl α-glycidoxypropyl tripropoxysilane, β-methyl α-glycidoxypropyl tributoxysilane, β-methyl β-glycidoxypropyltrimethoxysilane, β-methyl β-glycidoxy Propyltriethoxysilane, β-methyl β-glycidoxypropyl tripropoxysilane, β-methyl β-glycidoxypropyl tributoxysilane, β-methylγ-glycidoxypropyltrimethoxysilane, β-methylγ-glycidoxypropyltriethoxysilane, β Me Til γ glycidoxypropyl tripropoxy silane, β methyl γ glycidoxy propyl tributoxy silane, β methyl α glycidoxy butyl trimethoxy silane, β methyl α glycidoxy butyl triethoxy silane, β methyl α glycidoxy butyl Tripropoxysilane, β methyl α glycidoxybutyl tributoxysilane, β methyl β glycidoxybutyl trimethoxysilane, β methyl β glycidoxybutyl triethoxysilane, β methyl β glycidoxybutyl tripropoxysilane, β methyl β-glycidoxybutyl tributoxysilane, β-methylγ-glycidoxybutyltrimethoxysilane, β-methylγ-glycidoxybutyltriethoxysilane, β-methylγ-glycidoxybutyltripropoxysilane, β-methylγ-glycidoxybutyltri Butoxysilane, β Le δ glycidoxybutyl trimethoxysilane, beta-methyl δ-glycidoxy butyl triethoxysilane, beta-methyl δ-glycidoxy butyl tripropoxysilane, beta-methyl δ glycidoxybutyl tributoxysilane silane. These can be used alone or in combination of two or more.

(B) Component: Tetraalkoxysilane Basically, Si (OR1) ₄ (where R1 is represented by an alkyl group having 1 to 4 carbon atoms), specifically,
Examples thereof include tetraethoxysilane, tetramethoxysilane, tetrapropoxysilane, and tetrabutoxysilane. These can be used alone or in combination of two or more.

  The hydrolyzate of each silane compound (tri-tetraalkoxysilane) can be obtained by subjecting the silane compound to hydrolysis by adding 0.01-0.1 N (N) dilute acid in the presence of a lower alcohol. Specific examples of the dilute acid include hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, formic acid, oxalic acid, and sulfonic acid.

  The greatest feature of the present invention is that the above-mentioned alkoxysilane hydrolyzate contains a colloid of niobium pentoxide (hereinafter, simply referred to as “niobium oxide”) as the component (C).

Here, the niobium oxide colloid is made of niobium pentoxide (Nb ₂ O ₅ ) having a particle diameter of 1 to 50 nm, preferably 3 to 10 nm, more preferably 4 to 7 nm, which is a colloid using an anionic surfactant. Things are desirable.

  If the particle size is too small (less than 1 nm), abrasion resistance cannot be expected and aggregation is likely to occur, which may impair the uniformity of the coating film. Conversely, if the particle diameter is too large (over 50 nm), the coating film tends to be whitened and the appearance may be impaired.

  Here, the mixing ratio of the anionic surfactant to 100 parts of niobium oxide (fine particles) is preferably 10 to 100 parts, more preferably 30 to 70 parts.

  If the mixing ratio of the anionic surfactant is too small, the colloidal particles tend to aggregate and it is difficult to obtain a stable colloid. On the other hand, if it is excessive, thixotropy will occur and it will be difficult to use it as a paint.

  As the anionic surfactant, those exemplified below can be used.

1) Fatty acid soaps: potassium laurate, palm fatty acid potassium, palm fatty acid sodium, potassium myristate, potassium oleate, sodium oleate, potassium palmitate, potassium stearate, sodium stearate, mixed fatty acid sodium,
Special fatty acid sodium, etc.

2) Sulfonates (sulfonates)-Sodium dialkylsulfosuccinates (for example, sodium 2-ethylhexyl sulfonate succinate, sodium alkylbenzenesulfonates (for example, linear alkyl C10-C14 sodium benzenesulfonate),
3) Sulfates (sulfates) ... C8-18 alkyl sulfate (sodium salt), etc.
4) Polymer type anions: polycarboxylic acid type polymer anions, allyl ether copolymers, etc.
5) Other special anions: sodium acylmethyl taurate, sodium cocoyl isethionate, α-sulfo fatty acid ester sodium salt, sodium amide ether sulfonate, sodium alkyl ether sulfonate, oleyl sarcosine, lauroyl zalicosinate Sodium, etc. It can be used as a mixture of two or more of these different and the same species.

As a diluting solvent for dispersing the niobium oxide fine particles using the anionic surfactant, unsaturated aliphatic alcohols represented by the structural formula C _n H _2n-1 OH (n: 1 to 3) and 1 type or 2 types or more selected from esters such as 2-methoxyethanol, 2-ethoxyethanol, 1,2-dioxyethane, 2-butoxyethanol, 1-methoxy-2-propanol, etc. Can do.

  The dilution ratio at this time is 5 to 8 times the total amount of the niobium oxide fine particles and the anionic surfactant.

  If the dilution ratio of the dilution solvent is too small, the niobium oxide fine particles are likely to agglomerate. If the dilution ratio is excessive, it is difficult to obtain a sufficient film thickness at the time of application, and the effect of imparting wear resistance cannot be expected much.

  In addition, the manufacturing method of niobium oxide fine particles can be manufactured by the method of Unexamined-Japanese-Patent No. 8-143314, for example. That is, nitric oxide fine particles are obtained by adding citric acid to oxalic acid-stabilized niobium oxide and then adding an aqueous solution of ammonia (see abstract and paragraphs 0014 to 0018 of the specification).

  The mixing ratio of the niobium oxide fine particles to 100 parts of the alkoxysilane compound is usually appropriately set within the range of 40 to 100 parts.

  When the amount of the niobium oxide fine particles is too small, it is difficult to obtain a practical level of coating film hardness. When the amount of niobium oxide fine particles is excessive, a coating whitening phenomenon and appearance defects due to cracks are likely to occur during thermal polymerization after the coating is formed.

  Further, the hard coat composition of the present invention contains a trace amount of an ultraviolet absorber, an antioxidant, a disperse dye, an antistatic agent, a surfactant (the anionic surfactant) as necessary to improve the coating properties and appearance performance. It is possible to add.

  Specifically, a benzotriazole type, a benzophenone type or the like can be used as an ultraviolet absorber, and a hindered amine type is effective in combination with an antioxidant. A water disperse dye is used as the disperse dye.

  As the surfactant, a nonionic surfactant composed of dimethyl silicone oil having a hydrophobic group and polyether having a hydrophilic group is desirably used for the purpose of improving smoothness and antistatic properties. These characteristics can also be obtained by using a fluorosurfactant or the like. However, in the case of particularly high molecular weight fluorosurfactants, the niobium oxide microparticles are used in combination with the niobium oxide microparticles that are characteristic components of the present invention. Care must be taken when using it because it also has the property of facilitating aggregation. The amount of the surfactant used is 0.01 to 0.5 part, preferably 0.03 to 0.3 part, based on 100 parts of the hard coat composition (alkoxysilane compound + niobium oxide fine particles). If the amount of the surfactant is too small, it is difficult to obtain sufficient smoothness and antistatic properties. Conversely, if the amount of the surfactant is excessive, even if a silicone-based surfactant is used, spiders are likely to occur during film formation.

When a metal chelate is used as the low-temperature curing agent, for example, Cr (III), Co (III), Fe (III), Zn (II), In (III), Zr ( One or more of IV), Y (III), Al (III), Sn, Ti (II), and vanadium oxide (VO (II)) can be selected and used. The chelating agent is selected from ethylenediaminetetraacetic acid, hexafluoroacetone, trifluoroacetylacetone, acetylacetone, methyl acetoacetate, etc. Among them, acetylacetone iron (III), hexafluoroacetylacetone iron (III), acetylacetone tin, acetylacetone vanadyl Acetylacetone indium (III), acetylacetone zirconium (IV), acetylacetone cobalt (III), acetylacetone titanium (II), and acetylacetone aluminum (III) are desirable. The addition amount is 0.1 to 10 parts, preferably 0.3 to 5 parts, per 100 parts of (A) + (B) total hydrolyzate (solid content).

  As the organic carboxylic acid, trimellitic acid, trimellitic anhydride, itaconic acid, pyromellitic acid, and pyromellitic anhydride are preferable. The addition amount is 5 to 40 parts, preferably 15 to 25 parts, per 100 parts of (A) + (B) total hydrolyzate (solid content).

In the case of using a nitrogen-containing organic compound, methylimidazole and dicyandiamide are desirable.
The addition amount is 1 to 20 parts, preferably 5 to 10 parts, per 100 parts of (A) + (B) total hydrolyzate (solid content).

  And using the said hard-coat composition, a hard-coat coating film is formed in the single side | surface or both surfaces of the lens base material (optical base material) for spectacles formed with the organic glass which has refractive index: 1.60 or more. .

  And as organic glass, the polythiourethane resin of refractive index 1.60-1.67 is desirable.

Here, the polythiourethane resin is a polymer (resin) having a bond (-NHCOS-, -NHCSO- or -NHCSS-) in which at least one oxygen atom of the polyurethane bond (-NHCOO-) is replaced with a sulfur atom. ), One or more polyisocyanate components selected from polyisocyanate, polyisothiocyanate, isocyanate thioisocyanate and one or more selected from polythiol, polyol, polyolthiol. A known component comprising a polyol component can be suitably used (see JP-A-8-208792 etc.)
Here, as the isocyanate component, aliphatic, alicyclic, aromatic, and derivatives thereof, and sulfide, polysulfide, and thiocarbanyl (thioketone) derivatives in which sulfur is introduced into a part of their carbon chains are used as parent compounds. Can be listed. Of these, aliphatic or alicyclic compounds are desirable from the standpoint of yellowing resistance.

  In addition, examples of the polyol component include aliphatic, alicyclic, aromatic, and derivatives thereof, and those based on sulfides, polysulfides, and polythioethers in which sulfur is introduced into a part of their carbon chains. be able to. Of these, aliphatic or alicyclic ones are desirable from the standpoint of yellowing resistance.

  Specifically, it is desirable that the polythioether represented by the following chemical formula is composed of or is mainly composed of a base compound.

(但し、Ｒ１、Ｒ４：炭素数１〜６のアルキレン Ｒ２：炭素数１〜８のアルキレン)
他のポリオール成分としては分岐炭化水素多価アルコールのωメルカプト脂肪族カルボン酸の全置換エステルを好適に使用できる。

(However, R1, R4: C1-C6 alkylene R2: C1-C8 alkylene)
As the other polyol component, a fully substituted ester of an ω mercapto aliphatic carboxylic acid of a branched hydrocarbon polyhydric alcohol can be suitably used.

  Specifically, trimethylolpropane tris (2-mercaptoglycolate), pentaerythritol tetrakis (2-mercaptoglycolate), trimethylolpropane tris (3-mercaptopropionate), pentaerythritol tetrakis (3-mercaptopropionate) ) And the like.

  Examples of the method for applying the hard coat composition to the lens substrate (optical substrate) include brush coating, dip coating, roller coating, spray coating, and spin coating.

  The drying and curing conditions are, for example, 80 to 150 ° C., preferably 100 to 120 ° C. and 1 to 5 hours. Further, the cured film thickness of the hard coat film is appropriately selected within the range of 0.5 to 20 μm.

  In addition, the optical substrate (object to be coated) is usually pretreated by acid / alkali washing, degreasing washing with a solvent, plasma treatment, ultrasonic washing, or the like.

  A primer film is preferably provided between the optical substrate and the hard coat film. The primer film has an effect of improving impact resistance and adhesion.

  As a specific primer composition, the above-mentioned niobium oxide microparticles are dispersed in a colloidal state in which all or the main component of the film-forming resin is thermoplastic polyurethane (TPU) or ester-based thermoplastic elastomer (TPEE). TPU-based and TPEE-based primer compositions.

  Here, TPU means that a thermoplastic elastomer composed of a soft segment composed of a long-chain polyol and polyisocyanate and a hard segment composed of a short-chain polyol and polyisocyanate is added in the form of an aqueous emulsion.

  TPEE is a multi-block copolymer using polyester as a hard segment and polyether or polyester as a soft segment. -10/90.

  Furthermore, it is desirable to provide an optical inorganic thin film (antireflection film, reflection increasing film, interference filter) on the surface side of the hard coat film.

Antireflective coatings that can be formed on cured coatings can be formed by dry plating methods such as vacuum deposition, sputtering, and ion plating of inorganic powders such as metals, metal oxides, and metal fluorides. Products include silicon dioxide, titanium (IV) oxide, tantalum oxide (V
), Antimony (III) oxide, zirconium oxide, and aluminum oxide. Examples of the metal fluoride include magnesium fluoride. As a more specific structure of the inorganic substance, the following structure is used.

(α) SiO2 / ZrO2: 1 / 4λ, ZrO2: 1 / 2λ, SiO2: 1 / 4λ
(β) SiO2 / TiO2: 1 / 4λ, TiO2: 1 / 2λ, SiO2: 1 / 4λ

  Examples and comparative examples performed for confirming the effects of the present invention will be described below. In addition, Table 5 shows a list of compounding prescriptions for each hard coat composition.

In Table 5, “γGPTS” means “γ glycidoxypropyltrimethoxysilane” and “TEOS” means “ethyl silicate”.
<Example 1>
(A) Preparation of each composition / optical substrate (i) Preparation of hard coat composition
1) Preparation of hydrolyzed organoalkoxysilane 200 parts of γ-glycidoxypropyltrimethoxysilane, 40 parts of ethyl silicate and 50 parts of methyl alcohol were added and 70 parts of 0.01N hydrochloric acid was added dropwise with stirring for a whole day and night. Hydrolyze. This gives a hydrolyzate.

  2) Preparation of hard coating composition paint

  To the hydrolyzate prepared in 1) above, 480 parts of ethanol-dispersed Nb sol (Taki Chemical Co., Ltd. “Nd-AC25E” non-volatile content 25%, particle size 5 nm) 480 parts, 2-ethoxyethanol 100 parts and anhydrous triethyl as a low temperature curing catalyst. 48 parts of merit acid and 15 parts of dicyandiamide are added and stirred overnight, and then filtered through a 1 μm filter to obtain a hard coating composition paint having a refractive index of 1.60.

(ii) Preparation of primer composition a) TPU-based primer composition Nonvolatile content 33% water-dispersed polyurethane (Daiichi Kogyo Seiyaku Co., Ltd., trade name "Superflex 170") 84 parts, methyl alcohol 300 parts, pure water 100 150 parts of ethanol-dispersed Nb sol (Taki Chemical Co., Ltd. “Nd-AC20E” non-volatile content 20% particle size 5 nm) was added with stirring after mixing, and the mixture was stirred for 2 hours, filtered through a 1 μm filter, and a primer composition having a refractive index of 1.60. Get paint.

b) Preparation of TPEE primer composition>
Commercially available ester-based TPE non-volatile content 27% “Takamatsu Yushi Co., Ltd. water-dispersed emulsion product name Bes Resin A-160P” 100 parts, methyl alcohol 300 parts, pure water 100 parts ethanol dispersed Nb sol (Taki Chemical Co., Ltd. “Nd -AC20E "non-volatile content 20% particle diameter 5 nm) 200 parts, stirred for 2 hours, and then filtered through a 1 µm filter to obtain a primer composition paint having a refractive index of 1.64.

(iii) Fabrication of plastic lens (optical substrate)
<Raw material (a)>
98 parts of dicyclohexylmethane 4,4′-diisocyanate, 0.25 part of dibutyltin dichloride as a curing catalyst, 0.2 part of an alkyl phosphate (alcohol C8-C12) salt as an internal mold release agent, 2-benzyl as an aromatizing agent 0.3 parts of 2-propanol and 2 parts of a high molecular weight ultraviolet absorber (molecular weight of 500 or more) were added, and the mixture was sufficiently stirred for 1 hour at a liquid temperature of 17 ° C. in a nitrogen gas atmosphere.

  Thereafter, 64 parts of 4-mercaptomethyl 3,6-dithia-1,8-octanedithiol was further added, and the mixture was sufficiently stirred at a liquid temperature of 17 ° C. under a nitrogen gas atmosphere for 30 minutes.

Then, using a vacuum pump, the mixture was degassed for 1 h with stirring at a liquid temperature of 17 ° C. and 1.33 × 10 ² Pa (1 Torr), filtered through a 1 μm filter, and a polythiourethane lens raw material having a refractive index of 1.60 was prepared.

<Raw material (b)>
50 parts of m-xylylene diisocyanate, 0.01 part of dibutyltin dichloride as a curing catalyst, 0.1 part of an alkyl phosphate ester (alcohol C8-C12) salt as an internal mold release agent, and 2-phenyl-2-aldehyde as a fragrance imparting agent 0.2 parts of propanol, 0.1 part of a blue dye as a bluing agent to reduce the yellowness of m-xylylene diisocyanate, and 1 part of a high molecular weight ultraviolet absorber (molecular weight of 500 or more) are added. The mixture was sufficiently stirred for 1 h at a liquid temperature of 10 ° C. under a nitrogen gas atmosphere.

  Thereafter, 50 parts of 4-mercaptomethyl 3,6-dithia-1,8-octanedithiol was further added, and the mixture was sufficiently stirred for 10 minutes at a liquid temperature of 10 ° C. in a nitrogen gas atmosphere.

Then, using a vacuum pump, degassing for 40 minutes while stirring at a liquid temperature of 10 ° C. and 1.33 × 10 ² Pa (1 Torr), and then filtering through a 1 μm filter to prepare a polythiourethane lens raw material having a refractive index of 1.67. .

<Raw material (c)>
100 parts of 2,5-bicyclo [2,2,1] heptanebis (methylisocyanate), 0.1 part of dibutyltin dichloride as a curing catalyst, 0.3 part of an alkyl phosphate (alcohol C8-C12) salt as an internal release agent Then, 0.2 part of ethyl caproate as an aroma imparting agent and 2 parts of a high molecular weight ultraviolet absorber (molecular weight of 500 or more) were added, and the mixture was sufficiently stirred for 1 hour at a liquid temperature of 15 ° C. in a nitrogen gas atmosphere.

  Thereafter, 50 parts of pentaerythritol tetrakis (3-mercaptopropionate) and 50 parts of 4-mercaptomethyl 3,6-dithia-1,8-octanedithiol were added, and the liquid temperature was 15 ° C. under a nitrogen gas atmosphere for 1 hour. Stir well.

Then, using a vacuum pump, the mixture was degassed for 1 h while stirring at a liquid temperature of 15 ° C. and 1.33 × 10 ² Pa (1 Torr), filtered through a 1 μm filter, and a polythiourethane lens raw material having a refractive index of 1.60 was prepared.

  The composition liquids (a), (b), and (c) described above are poured into a circular glass mold and heated and cured under the following temperature conditions.

<Raw material (a)>
40 ° C. × 7 h → 40 ° C. to 80 ° C. over 5 hours → 80 ° C. to 130 ° C. over 4 h → 130 ° C. × 2 h → 130 ° C. to 40 ° C. over 4 h
<Raw material (b)>
30 ° C. × 9 h → Temperature rise from 30 ° C. to 60 ° C. over 2 h → Temperature rise from 60 ° C. to 100 ° C. over 2 h → Temperature rise from 100 ° C. to 120 ° C. over 2 h → 120 ° C. × 2 h → 120 ° C. to 40 ° C. Cool to 4 ° C over 4h

<Raw material (c)>
35 ° C. × 4 h → 30 ° C. to 50 ° C. over 2 h → 50 ° C. × h → 50 ° C. to 90 ° C. over 2 h → 90 ° C. to 120 ° C. over 2 h → 120 ° C. × 2 h → Cooling from 120 ° C. to 40 ° C. over 4 hours In addition, each plastic lens for eyeglasses prepared above is subjected to plasma treatment after being dipped, washed and dried in an aqueous caustic soda solution.
(C) Forming method of each coating film (i) Formation of primer coating film The lens base material prepared above is dipped in the primer coating material prepared above, and then pulled up at 160 mm / min for coating. The applied plastic lens is preliminarily dried at 100 ° C. for 20 minutes, and then a primer coating film is formed.

(Ii) Formation of Hard Coat Film The lens base material on which the primer film is formed is dipped in the hard coat composition prepared above and then applied at a rate of 160 mm / min. The coated lens substrate was pre-dried at 100 ° C. for 20 minutes and then heat-treated at 120 ° C. for 2 hours to cure the hard coat film.

(Iii) Formation of antireflection film On the lens base material having the hard coat film obtained in (ii) above, an inorganic substance is formed by a vacuum deposition method with the following configuration.

  Each of the above (α) configurations was carried out as an inorganic substance for the antireflection film.

The plastic lens having the composite film thus obtained is determined by the following evaluation method.
The test results are shown in Table 1.

(α) SiO2 / ZrO2: 1 / 4λ, ZrO2: 1 / 2λ, SiO2: 1 / 4λ
(D) Test (judgment) method Each test piece (multi-coated spectacle lens) prepared above was tested for the following items.

(I) Evaluation of optical physical properties Measurement was performed using an Olympus reflectometer, model USPM-RU-2, and the hard film thickness and refractive index were determined.

(Ii) Appearance Investigate interference fringes, transparency, coloring, and surface condition by visual observation.

<Criteria>
Interference fringes: ◎: No good at all, ○: Good, △: Slightly conspicuous, ×: Very conspicuous Transparency ... ○: Good clear, ×: Slightly spider (Transmittance is 1% lower than ○) .)
(iii) Adhesiveness 100 galleys that reach a 1 mm substrate on the coating surface are put on the coating film with a steel knife, and cellophane adhesive tape (manufactured by Nichiban) is firmly attached and peeled rapidly in the direction of 90 degrees. Evaluate based on criteria.

<Criteria>
A: No peeling 10 times or more AB: Dot-like or linear peeling along the scratched line B: Planar peeling along the scratched line (20% or less) However, the peeling area 1/2 or less of the first grid C: Surface following the scratched line Peeling (20% or more) However, the peeling area of the first square is 1/2 or less D: Surface peeling along the knurled line However, the whole peeling area of the first square As for secondary adhesion, after immersion in warm water at 80 ° C for 10 minutes The determination is performed in the same manner.

(IV) Abrasion property With respect to the product which has been processed up to the vapor deposition film processing, # 0000 steel wool is used to rub the cured coating film with a load of 600 g, and the result is judged and evaluated with the naked eye. For hard film processing up to 200g load on JIS # 502 sand eraser.

<Criteria>
3A: scratch area is 0%
2A: Scratch area exceeds 1% and less than 2% A: Scratch area exceeds 3% and less than 10% AB: Scratch area exceeds 10% and less than 30% B: Scratch area exceeds 30% and 60 Less than% C: The area of the scratch is 60% or more. D: The area of the scratch is the entire surface.

(V) Staining
2 parts of Seiko-Brown disperse dye, dispersant: 0.5 part of Diapon T in 1 liter of pure water, and a lens coated with a hard coating composition at a liquid temperature of 92 ° C. is immersed for 5 minutes to adjust the degree of coloration. Measure with transmittance.

(Vi) Weather resistance test Exfoliation status in the same manner as the primary adhesion test in (iii) above after exposure for 200 h in an accelerated weather resistance test ("Sunshine Super Long Life Weather Meter" manufactured by Suga Test Instruments Co., Ltd.) Determine.

  Also investigate transparency, coloration, and surface condition after exposure.

(Vii) Light resistance test
Using a Q-SUN / Xe-1 xenon accelerated light resistance tester manufactured by Q-PANEL, UVA is continuously irradiated at a temperature of 340 nm and a temperature of 60 ° C. for 40 hours. Sample lens is dyed to 50% color after applying hard coating composition (5) Same as dyeing test dye) and then antireflection film is used to measure transmittance before and after UV irradiation. Do.

(Viii) Impact resistance It is judged whether or not a 16.2 g steel ball is dropped from the height of 1.27 m to the center of the test sample and penetrated. ○ No penetration, × penetration. A test lens sample having a spherical surface with a center thickness of 2 mm and an edge thickness of 8 mm was used, and the test was performed under conditions of room temperature, 25 ° C., and humidity of 45%.
<Example II>
200 parts of γ-glycidoxypropyltrimethoxysilane, 10 parts of ethyl silicate, and 50 parts of methyl alcohol are added, and 70 parts of 0.01 N hydrochloric acid is added dropwise with stirring to perform hydrolysis overnight. This gives a hydrolyzate.

  800 parts of ethanol-dispersed Nb sol (Taki Chemical Co., Ltd. “Nd-AC25E” nonvolatile content 25%, particle size 5 nm), 50 parts of 1-methoxy-2-propanol and 5 parts of acetylacetone aluminum as a low-temperature curing catalyst were added to the hydrolyzate. In addition, the mixture is stirred for a whole day and night and filtered through a 1 μm filter to obtain a hard coating composition paint having a refractive index of 1.64.

In order to check whether or not the niobium oxide fine particles in the examples were caused by the film performance of the coating film, the film performance was confirmed by changing to composite fine particles made of titanium oxide.
(Comparison with the prior application patent paint composition JP-B 57-42665, optical plastic molding paint composition 25776070)
<Comparative Example 1>
A spectacle lens substrate having a refractive index of 1.60 (a), a 1.67 (b), and a 1.60 (c) composition is used.

  The plastic lens is dipped in a caustic soda solution, washed and dried.

  γ-glycidoxypropyltrimethoxysilane 125 parts, ethyl silicate 110 parts, methanol 92 parts, methyl ethyl ketone 200 parts, methanol-dispersed titania composite fine particles (SiO2 / TiO2 = 0.235, Fe2O3 / TiO2 = 0.008 nonvolatile content 30% particle diameter 11 nm) 180 parts are added and 54 parts of 0.01 N hydrochloric acid are added dropwise with stirring to perform hydrolysis overnight. This gives a hydrolyzate.

To the above hydrolyzate, 1.5 parts as a surfactant (trade name “L7002” manufactured by Nihon Unika Co., Ltd.) and 12 parts of itaconic acid and 5 parts of dicyandiamide as a low-temperature curing catalyst are added, stirred overnight and filtered, and then coated with a hard coating composition. Get.
<Comparative example 2>
A plastic lens for spectacles having a refractive index of 1.60 (a), 1.67 (b), and 1.60 (c) is used.

  The plastic lens is dipped in a caustic soda solution, washed and dried.

  To 382 parts of γ-glycidoxypropyltrimethoxysilane and 56 parts of ethyl silicate, 350 parts of methyl alcohol is added, and 111 parts of 0.02 normal hydrochloric acid is added dropwise with stirring to perform hydrolysis overnight. To this was added 0.12 part of a fluoroalkyl ester (trade name “Florard FC430” manufactured by Sumitomo 3M) as a surfactant, 67 parts of itaconic acid and 17 parts of dicyandiamide as a catalyst, and the mixture was stirred overnight and filtered to hard coat composition paint Get.

After being immersed in the hard coating composition paint obtained on the plastic lens, it is pulled up and coated at 105 mm / min. The coated lens substrate was pre-dried at 110 ° C. for 20 minutes, and then heat-treated at 100 ° C. for 4 hours to cure the hard coat composition.
<Test results and discussion>
Tables 1 to 5 show the test results of the above Examples and Comparative Examples. From these results, the following can be understood.

With respect to the problem to be solved by the present invention in terms of maintaining the property of suppressing the light interference of the hard coat for the high refractive lens:
Table 1 (Example 1) Refractive index 1.60 (a) (c) composition Refractive index 1.60 (a) (c) composition of Table 4 (Comparative Example 2) with respect to polythiourethane resin lens In comparison with the time of coating on the polythiourethane resin lens, the present invention obtained excellent results in the determination of appearance and interference fringes.

  Table 2 (Example 2): Refractive index 1.67 (b) To composition polythiourethane resin lens Refractive index 1.67 (b) composition polythiourethane resin lens of Table 4 (Comparative Example 2) Compared with the coating film of the present invention, the present invention obtained better results in the determination of the appearance and interference fringes.

  From these results, the present invention is an invention corresponding to a polythiourethane resin lens having a refractive index of 1.60 to 1.67.

  Table 3 (Comparative Example 1): Appropriate results were obtained in appearance and interference fringe determination, and the properties of suppressing light interference of the hard coat were obtained, but iron oxide in iron oxide / titanium oxide composite oxide fine particles However, it has been confirmed that the blackening phenomenon is observed after the weather resistance test due to the influence of ultraviolet rays, and the aesthetic appearance is impaired.

  These phenomena have not been confirmed in all the lenses obtained in Table 1 (Example 1) and Table 2 (Example 2).

  In Table 3 (Comparative Example 1), it was confirmed that the titanium oxide in the iron oxide / titanium oxide composite oxide fine particles had a decolorization phenomenon of about 46% with respect to the dyeing and coloring amount before the weather resistance test due to the influence of ultraviolet rays. On the other hand, in Table 1 (Example I) and Table 2 (Example 2) in which niobium oxide was used as a substitute without using titanium oxide, the decolorization rate was about 16% with respect to the coloring amount in the same test. Stays.

Claims (6)

A hard coat composition applied to an optical element formed of organic glass,
In the hydrolyzate of alkoxysilane , niobium pentoxide (Nb ₂ O ₅ : hereinafter simply referred to as “niobium oxide”) fine particles are dispersed in a colloidal state ,
The hydrolyzate of the alkoxysilane is
Component (A):
General formula

(However, R1 is H or CH ₃ , R2 is an alkylene group having 1 to 4 carbon atoms, and R3 is an alkyl group having 1 to 4 carbon atoms.)
A hydrolyzate of trialkoxysilane represented by:
(B) General formula
Hydrolyzate of tetraalkoxysilane represented by Si (OR1) ₄ (where R1 is represented by an alkyl group having 1 to 4 carbon atoms)
A hard coat composition having a mixing ratio of (A) component / (B) component = 7.5 / 2.5 to 9.5 / 0.5. The hard coat composition according to claim 1, wherein a mixing ratio of the niobium oxide fine particles to 100 parts by mass of the alkoxysilane is 40 to 100 parts by mass. An optical system comprising a hard coat film formed of the hard coat composition according to claim 1 or 2 on one or both sides of an optical substrate formed of an organic glass having a refractive index of 1.60 or more. element. The optical element according to claim 3 , wherein the organic glass is a polythiourethane resin having a refractive index of 1.60 to 1.67. The optical element according to claim 3 , further comprising a primer film between the optical substrate and the hard coat film. 6. The optical element according to claim 5 , further comprising an optical inorganic thin film (including an antireflection film, a reflection increasing film, and an interference filter) on the surface side of the hard coat film.