Process for transferring a coating onto a surface of a lens blank

• US 20040194880A1
• Filed: 01/02/2004
• Published: 10/07/2004
• Est. Priority Date: 07/02/2001
• Status: Active Grant

• Current Assignee: Essilor International SA (EssilorLuxottica SA)
• Original Assignee: Essilor International Compagnie Generale D Optique (EssilorLuxottica SA)
• Inventors: Adileh, Fadi O, Weber, Steven, Jiang, Peiqi, Turshani, Yassin Yusef
• Granted Patent: US 7,455,796 B2
• Time in Patent Office: Days
• US Class Current: 156/285
• CPC Class Codes: B29C 2035/0827 using UV radiation
• CPC Class Codes: B29C 2063/485 the liquid being an adhesive
• CPC Class Codes: B29C 63/16 applied by "rubber" bag or diaphragm
• CPC Class Codes: B29C 63/22 using layers or sheathings having a shape adapted to the shape of the article B29C63/26 and B29C63/38 take precedence
• CPC Class Codes: B29C 65/1406 Ultraviolet [UV] radiation
• CPC Class Codes: B29C 65/1435 at least passing through one of the parts to be joined, i.e. transmission welding
• CPC Class Codes: B29C 65/1483 coated on the article
• CPC Class Codes: B29C 65/483 Reactive adhesives, e.g. chemically curing adhesives
• CPC Class Codes: B29C 65/4835 Heat curing adhesives
• CPC Class Codes: B29C 65/4845 Radiation curing adhesives, e.g. UV light curing adhesives
• CPC Class Codes: B29C 65/4865 containing additives C09J11/00 and subgroups take precedence
• CPC Class Codes: B29C 65/52 characterised by the way of applying the adhesive B29C65/50 takes precedence; apparatus for applying liquids in general B05C; processes for applying liquids in general B05D
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/301 Three-dimensional joints, i.e. the joined area being substantially non-flat B29C66/5223, B29C66/5224, B29C66/5225 take precedence
• CPC Class Codes: B29C 66/452 the article having a disc form, e.g. making CDs or DVDs
• CPC Class Codes: B29C 66/545 one hollow-preform being placed inside the other
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/7315 Mechanical properties
• CPC Class Codes: B29C 66/73161 Roughness or rugosity
• CPC Class Codes: B29C 66/7338 at least one of the parts to be joined being polarising
• CPC Class Codes: B29C 66/7352 : Thickness, e.g. very thin
• CPC Class Codes: B29C 66/73921 : characterised by the materials of both parts being thermoplastics
• CPC Class Codes: B29C 66/80 : General aspects of machine operations or constructions and parts thereof
• CPC Class Codes: B29C 66/8122 : characterised by the composition of the material constituting the pressing elements, e.g. constituting the welding jaws or clamps
• CPC Class Codes: B29C 66/81264 : Mechanical properties, e.g. hardness
• CPC Class Codes: B29C 66/81267 : Transparent to electromagnetic radiation, e.g. to visible light
• CPC Class Codes: B29C 66/81422 : being convex
• CPC Class Codes: B29C 66/81423 : being concave
• CPC Class Codes: B29C 66/81455 : being a fluid inflatable bag or bladder, a diaphragm or a vacuum bag for applying isostatic pressure inflatable element positioned between the joining tool and a backing-up part B29C66/82421
• CPC Class Codes: B29C 66/83221 : cooperating reciprocating tools, each tool reciprocating along one axis
• CPC Class Codes: B29D 11/00009 : Production of simple or compound lenses
• CPC Class Codes: B29D 11/0073 : Optical laminates
• CPC Class Codes: B29K 2069/00 : Use of PC, i.e. polycarbonates or derivatives thereof, as moulding material
• CPC Class Codes: B29K 2669/00 : Use of PC, i.e. polycarbonates or derivatives thereof for preformed parts, e.g. for inserts
• CPC Class Codes: B29K 2869/00 : Use of PC, i.e. polycarbonates or derivatives thereof as mould material
• CPC Class Codes: B29K 2995/0027 : for light outside the visible spectrum
• CPC Class Codes: B29K 2995/007 : Hardness
• CPC Class Codes: B29K 2995/0072 : Roughness, e.g. anti-slip
• CPC Class Codes: B29K 2995/0089 : Impact strength or toughness
• CPC Class Codes: B29L 2011/0016 : Lenses
• CPC Class Codes: Y10T 156/1744 : Means bringing discrete articles into assembled relationship
• CPC Class Codes: Y10T 428/31507 : Of polycarbonate

Abstract

A process for transferring a coating onto at least one optical surface of a lens blank which comprises:

providing a lens blank having at least one geometrically defined surface;

providing a support having an internal surface bearing a coating and an external surface;

depositing on said geometrically defined surface of said lens blank or said coating a pre-measured amount of a curable glue;

moving relatively to each other the lens blank and the support to either bring the coating into contact with the curable glue or bring the curable glue into contact with the geometrically defined surface of the lens blank;

applying a sufficient pressure onto the external surface of the support so that the thickness of a final glue layer after curing is less than 100 micrometers;

curing the glue; and

withdrawing the mold part to recover the lens blank with the coating adhered onto its geometrically defined surface.

Claims

1-41. -41. (Canceled)

42. A process for transferring a coating onto at least one geometrically defined surface of a lens blank which comprises:

providing a lens blank having at least one geometrically defined surface;

providing a mold part having an internal surface bearing a coating and an external surface;

depositing on said geometrically defined surface of said lens blank or said coating a pre-measured amount of a curable glue;

moving relatively to each other the lens blank and the support to either bring the coating into contact with the room temperature or UV curable glue or bring the glue into contact with the geometrically defined surface of the lens blank;

applying a sufficient pressure onto the external surface of the support so that the thickness of a final glue layer after curing is less than 100 micrometers;

curing the glue; and

withdrawing the mold part to recover the lens blank with the coating adhered onto the geometrically defined surface thereof.

43. The process of claim 42, wherein the mold part is a rigid mold part having an internal surface corresponding to the geometrically defined surface of the lens blank.

44. The process of claim 42, wherein the mold part is a flexible mold part having an internal surface conformable to the geometrically defined surface of the lens blank when brought into contact therewith.

45. The process of claim 44, wherein the flexible mold part is urged against the lens blank by means of an inflatable membrane.

46. The process of claim 45, wherein the geometrically defined surface of the lens blank is a back spherical surface and the base curvature of the flexible mold (BC) and the base curvature of the spherical surface of the lens blank (BL) fulfill the relationship 0<

BC−

BL<

1.5.

47. The process of claim 46, wherein 0.2<

BC−

BL<

1.

48. The process of claim 45, wherein the geometrically defined surface of the lens blank is a back cylindric surface and the base curvature of the flexible mold (BC) and the base curvatures of the cylindric surface of the lens blank (BLR, BLr) fulfill the relationship BLR<

BLr and

a) if BLr−

BLR≦

3.5

0<

BC−

BLR<

3}

|BC−

BLr|<

1}

b) if BLr−

BLR>

3.5

BLR<

BC<

BLr

49. The process of claim 48, wherein in (a)

0.2<

BC−

BLR<

2.5}

|BC−

BLr|<

0.5}

50. The process of claim 43, wherein the mold part is made of a plastic material.

51. The process of claim 43, wherein the mold part is made of polycarbonate.

52. The process of claim 44, wherein the mold part is made of plastic material.

53. The process of claim 44, wherein the mold part is made of polycarbonate.

54. The process of claim 44, wherein the mold part has a thickness of 0.3 to 1 mm.

55. The process of claim 42, wherein the geometrically defined surface of the lens blank is an optical surface.

56. The process of claim 42, wherein the geometrically defined surface of the lens blank has a roughness Sq ranging from 10⁻

3 to 2 μ

m.

57. The process of claim 42, wherein the thickness of the final cured glue layer is less than 80 μ

m.

58. The process of claim 42, wherein the thickness of the final cured glue layer is less than 50 μ

m.

59. The process of claim 42, wherein the thickness of the final cured glass layer ranges from 1 to 30 μ

m.

60. The process of claim 42, wherein the exerted pressure ranges from 5 to 30 Psi.

61. The process of claim 42, wherein the coating comprises an anti-reflective coating layer, an anti-abrasion coating layer, an impact resistant coating layer, coating layer, a photochromic coating layer, a dying coating layer a polarized, or a stack of two or more of these coating layers, a printed layer.

62. The process of claim 61, wherein the coating has a thickness of 50 micrometers or less.

63. The process of claim 42, wherein the lens blank is a semi-finished lens having one face already provided with a coating.

64. The process of claim 63, wherein the face already provided with a coating is the front face of the lens and the geometrically defined surface onto which the coating is transferred in the back surface of the lens.

65. A process for transferring coatings onto geometrically defined surfaces of a lens blank which comprises:

providing a lens blank having two geometrically defined surfaces;

providing two separate mold part having each an internal and an external surface;

forming a coating on each of the internal surfaces of said mold parts;

depositing on the geometrically defined surfaces of the lens blank or on the coatings a pre-measured amount of curable glue;

closing the mold parts onto the lens blank;

applying a pressure on the external surface of at least one mold part to spread the glue amounts so that the thickness of final cured glue layers is less than 100 μ

m;

curing the glue; and

withdrawing the mold parts to recover the lens blank with coatings adhered onto each of its geometrically defined surfaces.

66. The process of claim 65, wherein the mold parts are rigid mold parts having internal surfaces corresponding to the geometrically defined surfaces of the lens blank.

67. The process of claim 66, wherein the mold parts are made of a plastic material.

68. The process of claim 65, wherein the mold parts are flexible mold parts having internal surfaces that conform to the geometrically defined surfaces of the lens blank upon closure of the mold parts.

69. The process of claim 68, wherein the mold parts are made of a plastic material.

70. The process of claim 69, wherein the mold parts are made of polycarbonate.

71. The process of claim 65, wherein the mold parts have a thickness of 1 mm or less.

72. The process of claim 65, wherein the geometrically defined surface of the lens blank is an optical surface.

73. The process of claim 65, wherein the geometrically defined surface of the lens blank has a roughness Sq ranging from 10⁻

3 to 1 μ

m.

74. The process of claim 65, wherein the thickness of the final cured glue layer is less than 80 μ

m.

75. The process of claim 65, wherein the thickness of the final cured glue layer is less than 50 μ

m.

76. The process of claim 65, wherein the thickness of the final cured glue layer ranges from 1 to 30 μ

m.

77. The process of claim 65, wherein the exerted pressure ranges from 5 to 50 Psi.

78. The process of claim 77, wherein the exerted pressure ranges from 5 to 30 Psi.

79. The process of claim 78, wherein the exerted pressure ranges from 5 to 20 Psi.

80. The process of claim 65, wherein the coatings comprise an anti-reflective coating layer, anti-abrasion coating layer, impact resistant coating layer, a polarized coating layer, a photochromic coating layer, a dying coating layer, or a stack of two or more of these coating layers.

81. The process of claim 80, wherein the coatings have a thickness of 50 micrometers or less.

82. An apparatus comprising:

a fluid accumulator having an upper and a lower face and a fluid entrance, said lower face being partly formed by an inflatable membrane, and

a trunconical part projecting outwardly from the lower face of the accumulator comprising a greater base closed by at least part of the inflatable membrane and a smaller base forming a circular opening,

whereby, when during use pressurized fluid is introduced into the accumulator, deformation of the inflatable membrane is guided by the trunconical part.

83. The apparatus of claim 82, wherein the height of the trunconical part ranges from 10 to 50 mm.

84. The apparatus of claim 82, wherein the taper of the trunconical part ranges from 10 to 90°

.

85. The apparatus of claim 84, wherein the taper of the trunconical part ranges from 30 to 50°

.

86. The apparatus of claim 82, wherein the membrane is a light transparent membrane and the upper face of the accumulator comprises a transparent portion in register with the inflatable membrane.