KR102029256B1 - Polymerizable composition for plastic lens - Google Patents

Abstract

The embodiment relates to a polymerizable composition for a plastic lens, and the polymerizable composition for a plastic lens according to the embodiment can achieve better refractive index by optimizing the sulfur content in the composition, and the number of functional groups of the polythiol compound and the polyisocyanate compound. By controlling the molecular weight between and the crosslinking point it can maintain excellent mechanical properties, impact resistance, heat resistance and the like, it can be usefully used in the production of various plastic optical lenses such as spectacle lenses, camera lenses.

Description

Polymerizable composition for plastic lenses {POLYMERIZABLE COMPOSITION FOR PLASTIC LENS}

The embodiment relates to a polymerizable composition for plastic lenses and a polythiourethane-based plastic lens obtained therefrom.

Since the plastic optical material is lighter than the optical material made of an inorganic material such as glass and is not easily broken and has excellent dyeability, plastic materials of various resins are widely used as optical materials such as spectacle lenses and camera lenses.

Polythiourethane-based compounds have a higher refractive index than other plastic-based materials, and can be designed according to the desired refractive index, and thus are widely used as raw materials for optical materials. However, the polythiourethane-based compound has a disadvantage in that when the refractive index is excessively increased, other physical properties, such as impact resistance, strength, mechanical properties, heat resistance, and the like, which should be present as an optical lens, are lowered. Therefore, it is important that the polythiourethane-based compound used as a raw material of the plastic lens satisfies the mechanical properties and the heat resistance at the same time as the refractive index.

Sulfur (S) content, crosslinking density, etc. may be mentioned as the most important factors for determining physical properties of the lens prepared from the polythiourethane-based compound, such as refractive index, heat resistance, mechanical strength, impact resistance, and the like. Specifically, the polythiourethane-based compound may be prepared by a mold polymerization in which a polymerizable composition comprising a polythiol compound and a polyisocyanate compound is injected into a mold and heat cured. In this case, the physical properties of the polythiourethane-based compound is affected by the content of sulfur in the polymerizable composition, the number of functional groups of the polythiol compound and the polyisocyanate compound, the molecular weight between the crosslinking point, and the like.

For example, although Korean Patent Nos. 10-1594407 and Korean Patent No. 10-0180926 disclose polythiol compounds including a plurality of sulfur, the polythiol compounds are aliphatic compounds, and the number of functional groups, crosslinking densities, etc. There is a limit to increase. In addition, although the Republic of Korea Patent No. 10-1074450 discloses an aromatic polythiol compound containing a phenyl group, there is a disadvantage in that it does not secure sufficient refractive index when synthesizing a polythiourethane-based optical material due to the low content of sulfur.

Republic of Korea Patent No. 10-1594407 Republic of Korea Patent No. 10-0180926 Republic of Korea Patent No. 10-1074450

Accordingly, the embodiment is to provide a polythiourethane-based compound for an optical material excellent in physical properties such as refractive index, heat resistance, strength, impact resistance by optimizing the number of functional groups, crosslinking density, sulfur content and the like of the polythiol compound and the polyisocyanate compound.

Examples are polymerizable compositions comprising a bifunctional or higher polythiol compound and a bifunctional or higher polyisocyanate compound, wherein the polymerizable composition has an average number of functional groups (F _avg ) of 2.2 or more according to Equation 1 below, It provides a polymerizable composition for plastic lenses having a sulfur content of at least 7% and an average molecular weight (EQ _avg ) between crosslinking points according to equation (3) below 260 g / mol:

[Equation 1]

Average number of functional groups (F _avg ) = [(the number of functional groups of the polythiol compound 티 the number of moles of the polythiol compound) + (the number of functional groups of the polyisocyanate compound 몰 the number of moles of the polyisocyanate compound)] / (the number of moles of the polythiol compound + polyisocyanate compound) Forfeiture)

[Equation 2]

Sulfur content (%) = [{(number of sulfur atoms in polythiol compound + number of sulfur atoms in polyisocyanate compound) ⅹ 32} / (molecular weight of polythiol compound + molecular weight of polyisocyanate compound)] ⅹ 100

[Equation 3]

Average molecular weight (EQ _avg ) between crosslinking points = (molecular weight of polythiol compound / function number of polythiol compound) + (molecular weight of polyisocyanate compound / function number of polyisocyanate compound).

Furthermore, the embodiment provides a polythiourethane-based plastic lens prepared by heat curing the polymerizable composition in a mold.

The polymerizable composition for plastic lenses according to the embodiment may achieve better refractive index by optimizing the sulfur content in the composition, and by controlling the molecular weight between the number of functional groups and the crosslinking point of the polythiol compound and the polyisocyanate compound, Since the impact resistance, heat resistance and the like can be excellently maintained, it can be usefully used for the production of various plastic optical lenses such as spectacle lenses and camera lenses.

Examples are polymerizable compositions comprising a bifunctional or higher polythiol compound and a bifunctional or higher polyisocyanate compound, wherein the polymerizable composition has an average number of functional groups (F _avg ) of 2.2 or more according to Equation 1 below, It provides a polymerizable composition for plastic lenses having a sulfur (S) content of 7% or more and a molecular weight (EQ _avg ) between crosslinking points according to Equation 3 below 260 g / mol:

[Equation 1]

Average number of functional groups (F _avg ) = [(the number of functional groups of the polythiol compound 티 the number of moles of the polythiol compound) + (the number of functional groups of the polyisocyanate compound 몰 the number of moles of the polyisocyanate compound)] / (the number of moles of the polythiol compound + polyisocyanate compound) Forfeiture)

[Equation 2]

Sulfur content (%) = [{(number of sulfur atoms in polythiol compound + number of sulfur atoms in polyisocyanate compound) ⅹ 32} / (molecular weight of polythiol compound + molecular weight of polyisocyanate compound)] ⅹ 100

[Equation 3]

Average molecular weight (EQ _avg ) between crosslinking points = (molecular weight of polythiol compound / function number of polythiol compound) + (molecular weight of polyisocyanate compound / function number of polyisocyanate compound).

Specifically, the polymerizable composition may have an average number of functional groups (F _avg ) according to Equation 1 of 2.2 or more, 2.2 to 3.5, 2.2 to 2.9 or 2.2 to 2.7. The tensile strength may be improved in proportion to the average number of functional groups, and in particular, when the average number of functional groups is in the above range, the tensile strength of the manufactured lens may be maintained at an appropriate level.

In addition, the polymerizable composition may have a sulfur content according to Equation 2 of 7% or more, 10 to 40%, or 14 to 35%. When in the above range, the refractive index of the lens produced from the composition is more excellent, it is possible to produce a thin, strong impact resistance lens.

Furthermore, the polymerizable composition may have an average molecular weight (EQavg) between the crosslinking points according to Equation 3 below 260g / mol, 140 or more and less than 260g / mol, 150 or more and less than 260g / mol, or 160 or more and less than 260g / mol. have. When in the above range, the mechanical properties, such as strength, elongation, etc. of the lens produced from the composition can be maintained while maintaining excellent impact resistance and heat resistance.

Specifically, the average number of functional groups, the sulfur content and the average molecular weight between the crosslinking points of the composition should be adjusted and combined within an appropriate range, which is a key factor in controlling the optical and physico-mechanical properties of the polythiourethane-based plastic lens. Works.

More specifically, when the sulfur content is lower than the above range, the refractive index is lowered to increase the thickness of the lens, and when the sulfur content is higher than the above range, not only the manufacturing cost increases but also the mechanical properties of the lens also decrease. do. In addition, when the molecular weight between the crosslinking points is smaller than the above range, the flexibility of the lens may be lowered, and impact resistance may be lowered. When the molecular weight between the crosslinking points is larger than the above range, the impact resistance may be slightly improved, but heat resistance and hardness are low. Has a problem. Furthermore, when the average number of functional groups in the composition is smaller than the above range, the crosslinking density may not be sufficient, and thus the hardness and heat resistance may be reduced. When the average number of functional groups in the composition is larger than the above range, the crosslinking density is too large and the flexibility of the lens is insufficient. Impact resistance may be lowered.

The polythiol compound may include a plurality of sulfur, and specifically, may be a bifunctional or higher polythiol. The polythiol compound may have a weight average molecular weight of 200 to 1,500 g / mol and 220 to 1,400 g / mol. When in the above range, the molecular weight between the crosslinking point, that is, the crosslinking density can be adjusted within the required range, and has an appropriate level of viscosity during lens casting to facilitate workability, thereby improving the yield in manufacturing the lens.

The polythiol may be prepared and used by a known method, and commercially available ones may be purchased and used.

(n은 9 내지 12의 유리수) 및

(x, y 및 z는 각각 독립적으로 1 내지 10의 정수이고, x+y+z=20)으로 이루어진 군으로부터 선택되는 1종 이상일 수 있다.Examples of the polythiol compound include 1,9-dimercapto-3,7-dithianonane, 1,13-dimercapto-3,7, 11-trithiatridecane (1,13-dimercapto-3,7,11-trithiatridecane), glycol di (3-mercaptopropionate), 1,4-dithiane- 1,4-dithiane-2,5-diyldimethanethiol, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane (4-mercaptomethyl-1,8 -dimercapto-3,6-dithiaoctane), 2-mercaptomethyl-1,5-dimercapto-3-thiapentane, trimethylolpropane tri (3 Trimethylolpropane tri (3-mercaptopropionate), 4,8-di (mercaptomethyl) -1,11-dimercapto-3,6,9-trithiaoundecan (4,8) -di (mercaptomethyl) -1,11-dimercapto-3,6,9-trithiaundecane), 5,9-di (mercaptoethylthio) -1,13-dimercapto-3,7,11-trithiatri Decane (5,9-di (mercaptoethylthio) -1,13-dimercapto-3,7,11-trithiatridecan e), pentaerythritol tetra (3-mercaptopropionate), pentaerythritol tetra (mercaptoacetate),

(n is a rational number of 9 to 12) and

(x, y and z are each independently an integer of 1 to 10, and may be one or more selected from the group consisting of x + y + z = 20).

(n은 9 내지 12의 유리수),

(x, y 및 z는 각각 독립적으로 1 내지 10의 정수이고, x+y+z=20) 및 이들의 혼합물일 수 있다. Specifically, the polythiol compound is 1,4-dithiane-2,5-diylmethanethiol, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 2-mercaptomethyl -1,5-dimercapto-3-thiapentane, 4,8-di (mercaptomethyl) -1,11-dimercapto-3,6,9-trithiaundane, pentaerythritol tetra (3 Mercaptopropionate), pentaerythritol tetra (mercaptoacetate),

(n is a rational number of 9 to 12),

(x, y and z are each independently an integer from 1 to 10, and x + y + z = 20) and mixtures thereof.

The polyisocyanate compound is isophorone diisocyanate, 1,6-diisocyanatohexane, 1,3-bis (isocyanatomethyl) cyclohexane (1,3-bis ( isocyanatomethyl) cyclohexane), bis (4-isocyanatocyclohexyl) methane, m-xylene diisocyanate, 1,3,5-tris (6-iso) Cyanatohexyl) -1,3,5-triazine-2,4,6-trione (1,3,5-tris (6-isocyanatohexyl) -1,3,5-triazinane-2,4,6- trione) may be one or more selected from the group consisting of.

The polyisocyanate compound may have a weight average molecular weight of 150 to 510g / mol, or 160 to 500g / mol. When in the above range, the crosslinking density and viscosity can be adjusted to an appropriate level to improve the lens manufacturing yield.

The polymerizable composition may further include additives such as an internal mold release agent, a heat stabilizer, a reaction catalyst, an ultraviolet absorber, and a blueing agent according to the purpose.

As the ultraviolet absorber, benzophenone-based, benzotriazole-based, salicylate-based, cyanoacrylate-based, oxanilide-based, and the like may be used.

The internal mold release agent includes a fluorine-based nonionic surfactant having a perfluoroalkyl group, a hydroxyalkyl group or a phosphate ester group; Silicone-based nonionic surfactants having a dimethylpolysiloxane group, a hydroxyalkyl group or a phosphate ester group; Alkyl quaternary ammonium salts such as trimethylcetyl ammonium salt, trimethylstearyl, dimethylethylcetyl ammonium salt, triethyldodecyl ammonium salt, trioctylmethyl ammonium salt, diethylcyclohexadodecyl ammonium salt and the like; And components selected from acidic phosphate esters may be used alone or in combination of two or more thereof.

As said reaction catalyst, the well-known reaction catalyst used for manufacture of a polythiourethane type resin can be added suitably. For example, Dialkyl tin halide system, such as dibutyl tin dichloride and dimethyl tin dichloride; Dialkyl tin dicarboxylates such as dimethyl tin diacetate, dibutyl tin dioctanoate and dibutyl tin dilaurate; Dialkyl tin dialkoxides such as dibutyl tin dibutoxide and dioctyl tin dibutoxide; Dialkyl tin dithio alkoxides such as dibutyl tin di (thiobutoxide); Dialkyl tin oxides such as di (2-ethylhexyl) tin oxide, dioctyltin oxide and bis (butoxydibutyltin) oxide; It may be selected from the group consisting of dialkyl tin sulfides such as dibutyl tin sulfide. Specifically, it may be selected from the group consisting of dialkyl tin halides such as dibutyltin dichloride and dimethyltin dichloride.

The thermal stabilizer may be used one or two or more metal fatty acid salts, phosphorus, lead, organotin.

The bluing agent has an absorption band in the wavelength range of orange to yellow in the visible light region, and has a function of adjusting the color of the optical material made of resin. The bluing agent may include, but is not particularly limited to, a substance which shows, specifically, “blue to purple”. In addition, examples of the bluing agent may include dyes, fluorescent whitening agents, fluorescent pigments, inorganic pigments, and the like, and may be appropriately selected according to physical properties, resin colors, and the like required for optical components to be manufactured. The bluing agent may be used alone, or a combination of two or more species. In view of solubility in the polymerizable composition and transparency of the resulting optical material, a dye is preferred as the bluing agent. In view of the absorption wavelength, the dye may specifically be a dye having a maximum absorption wavelength of 520 to 600 nm, and more specifically a dye having a maximum absorption wavelength of 540 to 580 nm. From the viewpoint of the structure of the compound, an anthraquinone dye is preferable as the dye. The addition method of a bluing agent is not specifically limited, It can add to the preliminary monomer type. Specifically, the method of adding the bluing agent may be dissolved in a monomer, or a master solution containing a high concentration of bluing agent is prepared, and the method of dilution with a monomer or another additive using the master solution is used. There are three ways to do this.

The embodiment provides a method of manufacturing a polythiourethane-based plastic lens by heat curing the polymerizable composition as described above in a mold. Furthermore, the Example provides the polythiourethane-type plastic lens obtained by the said manufacturing method.

Specifically, the polymerizable composition is degassed under reduced pressure and then injected into a lens molding mold. Such degassing and mold injection can be carried out, for example, in a temperature range of 20 to 40 ° C. After injection into the mold, polymerization is usually carried out by gradually heating from a low temperature to a high temperature.

The temperature of the polymerization reaction may be, for example, 20 to 150 ℃, specifically may be 25 to 120 ℃.

The polythiourethane-based plastic lens is then separated from the mold.

The polythiourethane-based plastic lens can be manufactured in various shapes by changing the mold of the mold used in manufacturing. Specifically, the lens may be in the form of an eyeglass lens, a camera lens, or the like.

The reaction molar ratio of the polythiol compound and the isocyanate compound in the polymerization reaction may be 0.5 to 1.2: 1, or 0.5 to 1.1: 1.

The polythiourethane-based plastic lens may be subjected to surface polishing, antistatic treatment, hard coat treatment, anti-reflection for antireflection, high hardness, abrasion resistance, chemical resistance, anti-fogging, or fashion, as necessary. Physical and chemical treatments such as a coat treatment, a dyeing treatment, and a dimming treatment can be performed to improve the coating.

The polythiourethane-based plastic lens may have a refractive index of 1.55 to 1.70, 1.55 to 1.68, or 1.56 to 1.68. Further, the plastic lens may have a heat deformation temperature of 75 to 120 ℃, 78 to 110 ℃ or 80 to 110 ℃.

In addition, the plastic lens may have a tensile strength of 40 to 120kgf, 50 to 120kgf, or 40 to 110kgf and an elongation of 3 to 20%, 5 to 20%, or 3 to 15%. As described above, the tensile strength may increase in proportion to the number of functional groups in the polymerizable composition, but is not limited thereto. The tensile strength may be improved or decreased by the average molecular weight between the crosslinking points.

 Furthermore, the plastic lens may have an Abbe number of 30 to 46, 30 to 45, 30 to 44, or 31 to 44. Furthermore, the plastic lens may have excellent impact resistance because breakage, cracking, or the like does not occur even when a 16g steel ball is dropped at a height of 127 cm (see Experimental Examples (1) to (5)).

As described above, the polymerizable composition for plastic lenses according to the embodiment may achieve better refractive index by optimizing the sulfur content in the composition, and controlling the molecular weight between the number of functional groups and the crosslinking point of the polythiol compound and the polyisocyanate compound. Since mechanical properties, impact resistance, heat resistance and the like can be excellently maintained, it can be usefully used for the production of various plastic optical lenses such as spectacle lenses and camera lenses.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

[ Example ]

As the polythiol compound and the polyisocyanate compound used in the following examples, the compounds of Tables 1 and 2 were used.

Polythiol Compound (Th) Molecular Weight (MW) Functional Radix (F) Equivalent (EQ) Sulfur content (%) One

1,9-디메르캅토-3,7-디티아노난

1,9-dimercapto-3,7-dithianonane 228.5 2 114.3 56.0 2

1,13-dimercapto-3,7,11
Tritia tridecane 302.6 2 151.3 52.9 3

Glycol di (3-mercaptopropionate) 238.3 2 119.2 26.9 4

(n = 10.3)
800 2 400.0 8.0 5

1,4-dithiane-2,5-diylmethanethiol 212 2 106.0 60.4 6

2-mercaptomethyl-1,5-dimercapto
-3-thiapentane 200.4 3 66.8 63.9 7

Trimethylolpropane tree
(3-mercaptopropionate) 398.6 3 132.9 24.1 8

(x, y and z are each independently an integer from 1 to 10, x + y + z = 20)
1300 4 325.0 7.4 9

5,9-di (mercaptoethylthio) -1,13-dimercapto-3,7,11-trithiatridecane 486 4 121.5 59.3 10

Pentaerythritol tetra
(3-mercaptopropionate) 488.7 4 122.2 26.2 11

Pentaerythritol tetra
(Mercapto acetate) 432.6 4 108.2 29.6 12

4-mercaptomethyl-1,8-dimercapto
-3,6-dithiaoctane 260 3 86.7 61.5 13

4,8-di (mercaptomethyl) -1,11-dimercapto
-3,6,9-trithiaoundecan 366 4 91.5 61.2

Polyisocyanate Compound (Iso) Molecular Weight (MW) Functional Radix (F) Equivalent (EQ) One

이소포론 디이소시아네이트

Isophorone diisocyanate 222.2 2 111.1 2

1,6-diisocyanatohexane 168.2 2 84.1 3

1,3-bis (isocyanatomethyl) cyclohexane 194.2 2 97.1 4

Bis (4-isocyanatocyclohexyl) methane 262.4 2 131.2 5

m-xylene diisocyanate 188.2 2 94.1

Polymerizable  Preparation of the composition

The polythiol compound and the polyisocyanate compound were mixed uniformly in the composition and molar ratio as described in Tables 3 to 6 below. At this time, the polythiol compound was mixed according to the molar ratio based on 100 parts by weight of polyisocyanate. 0.01 parts by weight of dibutyltin dichloride was used as a polymerization catalyst, Zelec® UN 0.1 and 0.05 parts by weight of UV stabilizer Seesorb® 709 were added as an internal mold release agent, and a homogeneous mixture was prepared. For each sample (polymerizable composition) the average number of functional groups (F _avg ), the sulfur content and the average molecular weight (EQ _avg ) between the crosslinking points were calculated and the results are shown in Table 3 below.

Experimental Example  : Check property

The physical properties of the polymerizable compositions prepared above were measured as described below, and the measurement results are shown in Tables 3 to 6 below.

(1) refractive index (ne) and Abbe's number (ve)

After degassing for 1 hour at 1 torr, it was filtered through a 3 μm Teflon filter. The filtered polymerizable composition was injected into a glass mold mold assembled by tape. The mold mold was heated at a rate of 5 ° C./min from 25 ° C. to 120 ° C. and polymerized at 120 ° C. for 18 hours. Next, the cured resin in the glass mold mold was further cured at 130 ° C. for 4 hours, and then the molded body (plastic lens) was released from the glass mold mold. The refractive index and Abbe number were obtained at 20 degreeC using the Abbe refractometer DR-M4 about the obtained optical material.

(2) Heat deflection temperature (Tg, ℃)

For the plastic lens of item (1), glass transition temperature (Tg, heat deformation) at the permeation method (50 g load, pin wire 0.5 mmф, heating rate 10 ° C / min) using TMA Q400 (TA) Temperature) was measured.

(3) tensile strength and elongation

80 mm diameter, 2 mm thick flat standard lens specimens were prepared, and two holes were punched at the edges, and then measured using a universal testing machine (Universal Testing Mashine). The strength and elongation at break were calculated as tensile strength and elongation, respectively.

(4) impact resistance

After fixing the plastic lens manufactured in the same manner as in item (1), 16g of steel balls were dropped at a height of 127 cm to observe whether the lens was broken or cracked. When the surface of the lens was cracked or the lens was broken, F (Fail) was evaluated. If the surface state was good without being broken, P (Pass) was evaluated.

As shown in Tables 3 to 6, it can be seen that the refractive index of the lens increased in proportion to the sulfur content of the polymerizable composition. Furthermore, in most results, the tensile strength of the lens is increased in proportion to the average number of functional groups (F _avg ), so that the denser the crosslinking density, the better the tensile strength. In addition, lenses made from polymerizable compositions in which the average number of functional groups (F _avg ), the sulfur content and the average molecular weight (EQ _avg ) between the crosslinking points satisfy the above-mentioned ranges are not only refractive indexes, It can be seen that the optical properties such as water are excellent, and the heat deformation temperature is high, so the heat resistance is excellent. In addition, it can be seen that it shows a better level in terms of tensile strength, elongation and impact resistance.

Claims (11)

delete delete delete delete delete delete Bifunctional or higher polythiol compounds; And
In the polythiourethane-based plastic lens produced by heating and curing a polymerizable composition comprising a bifunctional or higher polyisocyanate compound in a mold,
The polythiol compound is 2-mercaptomethyl-1,5-dimercapto-3-thiapentane and 5,9-di (mercaptoethylthio) -1,13-dimercapto-3,7,11- At least one selected from the group consisting of trithiatridecane,
The polyisocyanate compound is 1,3-bis (isocyanatomethyl) cyclohexane,
The polymerizable composition has an average number of functional groups (F _avg ) according to Equation 1 below 2.2, a sulfur content according to Equation 2 below 7%, and a molecular weight between crosslinking points according to Equation 3 below ( EQ _avg ) is less than 260 g / mol,
Wherein the polythiourethane-based plastic lens has a tensile strength of 40 to 120 kgf and an elongation of 3 to 20%.
[Equation 1]
Average number of functional groups (F _avg ) = [(number of functional groups of polythiol compound x number of moles of polythiol compound) + (number of functional groups of polyisocyanate compound x number of moles of polyisocyanate compound)] / (moles of polythiol compound + polyisocyanate compound) Forfeiture)
[Equation 2]
Sulfur content (%) = [{(number of sulfur atoms in polythiol compound + number of sulfur atoms in polyisocyanate compound) × 32} / (molecular weight of polythiol compound + molecular weight of polyisocyanate compound)] × 100
[Equation 3]
Average molecular weight (EQ _avg ) between crosslinking points = (molecular weight of polythiol compound / function number of polythiol compound) + (molecular weight of polyisocyanate compound / function number of polyisocyanate compound). The method of claim 7, wherein
A polythiourethane-based plastic lens, wherein the lens has a refractive index of 1.55 to 1.70. The method of claim 7, wherein
Polythiourethane-based plastic lens, the lens has a heat deflection temperature of 75 to 120 ℃. delete The method of claim 7, wherein
A polythiourethane-based plastic lens, wherein the lens has an Abbe number of 30 to 46.