Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D11/00—Producing optical elements, e.g. lenses or prisms
  • B29D11/00009—Production of simple or compound lenses
  • B29D11/00038—Production of contact lenses
  • B29D11/00057—Production of contact lenses characterised by the shape or surface condition of the edge, e.g. flashless, burrless, smooth
• • G—PHYSICS
  • G02—OPTICS
  • G02C—SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
  • G02C7/00—Optical parts
  • G02C7/02—Lenses; Lens systems ; Methods of designing lenses
  • G02C7/04—Contact lenses for the eyes
• • G—PHYSICS
  • G02—OPTICS
  • G02C—SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
  • G02C7/00—Optical parts
  • G02C7/02—Lenses; Lens systems ; Methods of designing lenses
  • G02C7/04—Contact lenses for the eyes
  • G02C7/049—Contact lenses having special fitting or structural features achieved by special materials or material structures
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
  • B29D11/00—Producing optical elements, e.g. lenses or prisms
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/04—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/04—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics
  • G02B1/041—Lenses
  • G02B1/043—Contact lenses

Definitions

• the present application relates to a "soft" contact lens with excellent wear properties.
• a contact lens made of silicone in which a radial cross section on the inner surface has an edge ⁇ range between a turning point and the outer edge in which the cross-sectional contour is convex, in particular with a radius between 0.1 and 10 mm. Due to this edge contour, the lens slides particularly easily on the tear fluid film.
• the contact lens has a surface layer of a hydrophilic material, which further improves the wearing comfort.
• the problem is solved by a method in which a silicone precursor material is introduced and polymerized between a female and a male mold, and the polymerized contact lens is released from the mold by means of a contact lens-swelling liquid and finished without edge trimming. This will be the occurrence a cutting edge that could be perceived as disturbing avoided.
• the raw lens thus obtained is hydrophilized in a combined PECVD / CVD process, whereby particularly thick coatings are achieved.
• FIG. 1 a shows a schematic cross-sectional representation of a contact lens arranged on the cornea of an eye
• FIG. 1b shows a schematic detail enlargement of an edge region of the contact lens from FIG.
• FIG. 2 shows an electron micrograph of the edge region of the contact lens
• Figure 3 is a surface coating indicating
• FIG. 4 shows a flowchart for a production method of the contact lens according to the invention.
• Figure 5 is a cross-sectional view of a for manufacturing according to
• Figure 4 shows a suitable molding apparatus.
• FIGS. 1 a and 1 b The general form of a contact lens is shown in FIGS. 1 a and 1 b.
• the outer surface 2 of the lens is of course convex with an amount slightly different from that of the inner surface to provide the desired dioptric power.
• the curvatures or radii deviate from the central values in the following way: On the outer surface, an annular region 4 with a stronger (inward) curvature, that is to say a smaller radius, joins radially to the central region. On the outside, this can be followed by an area 5, which is again curved more slenderly, even conically (that is, unconstrained), or slightly outwardly (ie, negative). In terms of magnitude, however, the curvature is always smaller (ie the radius is greater) than in the first-mentioned transitional region 4, ie the lens runs smoothly.
• the inner surface 1 has radially to the central region with the elliptical surface then also an annular region, but less curved, that is flatter, which corresponds to a larger radius of curvature in this area.
• the radius of curvature in a sectional plane containing the optical axis of the lens passes through a turning point 6, d. H. the curvature of the line becomes zero first and then positive. For Gauss' plane curvature this means a change to negative values.
• the area 7 then adjoins this area, where the inner surface of the contact lens conforms to the global tangential plane;
• the curvature in the main plane of curvature perpendicular to the radial cutting plane is zero, so that the Gaussian surface curvature becomes zero and changes even more positively in the immediate edge region.
• the present invention gently on a cut edge-free outer edge to ongoing annular areas (see Figure 2) that a trouble-free sliding of the contact lens on the tear fluid film and at the same time a trouble-free sliding of the eyelid is made possible on the contact lens.
• the radius of the inner surface, ie the inverse curvature, along the radial cut surface for example between 0.1 and 4 mm, or on the one hand about 0.5 mm and / and on the other hand, less than 2 mm.
• the radial extent of the negatively curved surface area may be 1 ⁇ m to 1 mm, for example on the one hand above 10 ⁇ m and / or on the other hand below 100 ⁇ m.
• FIG. 3 shows a fluorescence diagram of a surface coating, as it can be applied for the hydrophilization of the inherently hydrophobic silicone base material of the contact lens.
• the core area of the lens is made of poly (dimethylsiloxane) with a Shore A hardness of 25.
• PAA polyacrylic acid
• the total thickness (line width) of the PAA coating is several tens of pm.
• the lens thickness at the measuring position (line spacing) is 118 pm.
• Coating was by PECVD followed by CVD.
• the pressure ratio was changed from an initially clear excess of argon (> 10: 1) to an equally significant argon deficit ( ⁇ 1:10) towards end, with decreasing total pressure.
• This was followed by an initial polymerization of anhydrous acrylic acid from the vapor phase at its normal vapor pressure, without plasma action and without the presence of inert gas.
• the initially plasma-assisted layer had a thickness of 20-30 nm, that is, on the order of about one tenth of the total layer thickness.
• Such layers have both optically and because of the strong hydrophilicity, physiologically excellent properties.
• the contact angle of the applied layer in water is less than 10 ° and typically 2-5 °. The favorable effects of the shaping according to the invention are specifically supported by this material treatment.
• FIG. 4 shows a flow chart of a method according to the invention.
• a female and a male mold are provided, and a precursor material for poly (dimethylsiloxane) is introduced into the female mold, sealed with the male part and kept at a temperature between 15 ° C-160 ° C for a period of 12-720 minutes polymerizes Sl (molding).
• the two moldings are rotated against each other by 180 ° or another sufficiently large angle (> 20 °), as long as the reaction mixture is just still viscous (over 1000 cP, typically about 4000 cP), so that excess silicone reliably separated and is displaced into the annulus between the moldings.
• the surface tension described above also produces the edge contour described above, which makes it possible to dispense with edge trimming or other edge processing which produces a cut edge (eg punching).
• edge trimming or other edge processing which produces a cut edge (eg punching).
• an alkane such as hexane or other non-polar or slightly polar solvent swollen S3, so that it dissolves S5 without mechanical action of the molding mold and of the production parts.
• the dipole moment of the solvent should be no more than 0.2 Debye.
• the starting material can be a liquid 2-component silicone from NuSil with a DK value of over 700 barrers.
• the lens is transferred after evaporation of the solvent in vacuo in a coating chamber and first cleaned with argon plasma (about 1 min) and prepared. Then follows a phase S7 with a slight argon excess of about 1: 1 to 2: 1 (partial pressure ratio) with respect to acrylic acid vapor, obtained from anhydrous acrylic acid.
• Exemplary pressures are 0.03 Torr for argon and 0.015 Torr for acrylic acid. After this phase, which lasts 10 to 90 minutes, a ten-minute period with closed argon supply and further reduced acrylic acid pressure (about 0.1 mTorr) follows.
• the plasma generator is then turned off and the lens is exposed to the saturation vapor pressure of the acrylic acid at room temperature until lens opacification indicates completion of the procedure (about 5 minutes).
• the contact lens is watered in hydrophilic liquid, for example isotonic saline, for 24 hours to remove any residue of the coating agent and steam sterilized at above 120 ° C.
• FIG. 5 a two-part molding mold is shown, which is suitable for carrying out the method described above.
• the lower female part 10 first takes up the reaction mixture and is then closed with the upper, male part 12, leaving a filled with the reaction mixture space 11 between them.
• the lower part 10 has draft angles 13 ', 13 ", which facilitate the assembly and separation of the mold parts 10 and 12.
• the annular space is designated 14.
• the extent of the irregularity can be quantified by assigning an ideal approximate circular shape to the projection of the outer edge, computationally, according to the criterion of minimum deviation squared sum.
• the mean square deviation is then a measure of the irregularity, and is at least 5000 ⁇ im 2 (converted to amounts: about 1% of half the lens diameter), but in embodiments may be more than 1000 ⁇ 2 or more than 10000 pm 2 .
• the contact lenses designed according to the invention can be used as association lenses, ie with or without refractive power for the physical protection of the cornea against irritation. This may be useful as a flanking, inherently non-therapeutic measure in a medical therapeutic eye treatment.
• a “predominant existence” means a mass fraction of more than 50%, in particular of more than 90% in its entirety.
• curvature the inverse radius of curvature, i. the radius of the Schmiegenikes to understand, where the sign is positive for convex surfaces and negative for concave surfaces.
• the Gaussian surface curvature is the product of the two main curvatures, that is to say negative if the two main curvatures have different signs (saddle surface), and then zero if one or both main curvatures are zero (eg cylinder and conical surface).

Landscapes

• Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• Ophthalmology & Optometry (AREA)
• General Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Mechanical Engineering (AREA)
• General Health & Medical Sciences (AREA)
• Eyeglasses (AREA)
• Casting Or Compression Moulding Of Plastics Or The Like (AREA)

Priority Applications (12)

Applications Claiming Priority (2)

Publications (1)

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Citations (8)

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• 2012
  • 2012-02-01 PL PL12000649T patent/PL2613180T3/pl unknown
  • 2012-02-01 EP EP12000649.9A patent/EP2613180B1/de not_active Not-in-force
  • 2012-02-01 ES ES12000649.9T patent/ES2474572T3/es active Active
• 2013
  • 2013-02-01 KR KR1020147023895A patent/KR20140133830A/ko not_active Ceased
  • 2013-02-01 AU AU2013206388A patent/AU2013206388B2/en not_active Expired - Fee Related
  • 2013-02-01 EP EP13703331.2A patent/EP2810107A1/de not_active Withdrawn
  • 2013-02-01 WO PCT/EP2013/000323 patent/WO2013083855A1/de not_active Ceased
  • 2013-02-01 IN IN7222DEN2014 patent/IN2014DN07222A/en unknown
  • 2013-02-01 BR BR112013022754-0A patent/BR112013022754A2/pt not_active Application Discontinuation
  • 2013-02-01 RU RU2014135280A patent/RU2014135280A/ru not_active Application Discontinuation
  • 2013-02-01 JP JP2013557143A patent/JP2014510946A/ja active Pending
  • 2013-02-01 US US14/004,760 patent/US20150036100A1/en not_active Abandoned
  • 2013-02-01 ES ES15002465.1T patent/ES2659021T3/es active Active
  • 2013-02-01 CN CN201380018315.2A patent/CN104204863B/zh not_active Expired - Fee Related
  • 2013-02-01 SG SG11201404482PA patent/SG11201404482PA/en unknown
  • 2013-02-01 EP EP15002465.1A patent/EP2985638B1/de not_active Not-in-force
• 2014
  • 2014-05-16 JP JP2014102517A patent/JP5913430B2/ja not_active Expired - Fee Related

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