FR2689648A1 - Method of coloring transparent optical elements - Google Patents

Abstract

A method of coloring a transparent optical element (11) comprising coating a predetermined surface (12) of the transparent optical element with a coloring agent to form a lightly colored transparent film (14) on that surface. Application, in particular to the coloring of spectacle lenses.

Description

PROCESS FOR COLORING TRANSPARENT OPTICAL ELEMENTS

  The present invention relates to a method for coloring

  transparent optical elements, for example lenses for

  your. In a known coloring process, a spectacle lens (for example a plastic lens) is immersed in the

  dyeing so that the microscopic asperities on the surface

  face of the lens are impregnated with dye In this process

  staining in which the spectacle lens is plunged

  In dyeing, the dyeing conditions inevitably vary-

  To some extent these variations are due to various factors, such as the temperature and density of the dye, the degree of polymerization, the porosity of the plastic lens to be colored, etc. Therefore, it is very difficult to manufacture

  series of plastic lenses having exactly the same

  to them, or to obtain a colored plastic lens whose color is exactly the same as the color of the sample In addition, in the case of a lens for glasses made of a plastic that is not very resistant to heat, a slight deformation of the surface of the

  lens can occur as a result of the heat of the opera-

dyeing.

  Many plastics have a surface that does not

  dye molecules to penetrate It is impossible to

  The plastics in which the dye molecules can not penetrate can not be used to make a colored spectacle lens, which limits the choice of materials which can be used to color these plastics using the aforementioned conventional dipping method. the

lens can be made.

  The main object of the present invention is to provide a simple coloring process in which many transparent optical elements can be colored simply and inexpensively with the desired color or colors, in a wider range of colors, and in which a color is obtained. specificity can be reproduced with greater accuracy than in the

known method.

  The basic concept of the present invention lies in the

  plication of a slightly colored transparent film on a surface

  external lens for glasses.

  Therefore, according to the present invention, an outer surface

  dull of a transparent optical element is coated with a

  staining to color the transparent optical element.

  The transparent optical element is, for example, a lens

  for spectacles The coloring process according to the present invention

  can be advantageously used especially when the spectacle lens is made of a glass or a plastic which does not

  not allow the dye molecules to penetrate. It turned out to be

  possible to color a conventional spectacle lens made of non-porous glass or plastic, thus

  dye molecules to penetrate However, the present invention

  This type of conventional lens can be colored by forming

  a lightly colored transparent layer of film on the "over-

outer face "of the lens.

  There are two types of coloring agents, namely dye-type agents containing dyes, and pigment-type agents containing pigments.

  used in the present invention, the pig-type agents

  are generally preferred to dyeing agents, in particular

  because of their weather resistance.

  For pigment type agents, it is preferable that the pig-

  It is intended to use light-permeable colored particles having an average diameter of less than 1 micrometer and, more preferably, less than 0.5 microns. If the particle diameter is greater than 1 micron, the appearance of the len It has been experimentally confirmed that good results can be obtained with a Neo-Alex NO 100 pigment marketed by Nihon Yakou Toryo Co Ltd, Japan. The present invention can also be applied to a

  Composite lens for spectacles consisting of at least two half

  laminated lenses An external jointing surface of one of the half-pellets is coated with a coloring agent to form a

  slightly colored transparent film on the optical element (that is,

  ie the half-lens) The half-lens is then glued on the other half-lens to the colored surface In this arrangement, since the slightly colored transparent film is located between the half-lenses, it is perfectly protected by the half-lenses.

  The slightly colored transparent film containing the pigments

  reinforces the connection between the half-lenses when the

  colored transparent film is heated or after a predetermined time

  Similarly, in the case of a single lens coated with the colored clear film, the adhesion of the colored transparent film to the lens can be increased by heating. The adhesion is increased automatically after a predetermined period of time.

  in practice, exposure to the outside of the transparent film

  Colored is not a problem.

  Spraying, rotating or impregnated coating

  mersion, known per se, can be used in the staining process. The present invention is described in detail below with reference to the accompanying drawings, in which: Figure 1 is a schematic view of a spectacle plastic lens to which the present invention is applied; Fig. 2 is a schematic view of a composite spectacle lens to which the present invention is applied; Figure 3 is an enlarged schematic view of a slightly colored transparent film applied to a plastic lens, prepared by a dyeing method according to the present invention; and FIG. 4 is a schematic view on a larger scale of a plastic lens which is provided with a colored layer which has

  was applied by a known immersion coloring method.

  In Figure 1, which illustrates the principle of the coloring process

  of the present invention, a plastic lens 1 to which

  a predetermined shape is given by a polymerization process

  The invention, known per se, is directly coated with a slightly colored transparent film layer 14 by means of a sprayer 13 on a surface, for example a rear surface 12 of the lens.

  The colored transparent film 14 may be a coloring agent

  pigment-type composition containing pigments or a colourant

  Preferably, a plurality of sprayers 13 containing coloring agents of different colors are prepared according to the color.

desired.

  It is also possible to color the lens 1 i 1 by super-

  position of colors on the lens.

  FIG. 3 is a schematic view on a larger scale of a coloring agent (i.e., a film) 14 applied to the outer surface of the lens 11. If the lens 11 'is colored by

  the conventional immersion coloring process, as

  4, the lens 11 'is impregnated with dye particles penetrating into the microscopic asperities of the porous plastic lens 11' in order to form the colored layer 14 '. It should be noted that, in the prior art, the colored layer 14 'is formed on the entire surface of the lens 11' which is immersed in the dye bath, whereas in the present invention the transparent colored film layer 14 is formed only on the required surface (s) (by example the external surface) of

1 O the lens 1 1.

  Figure 2 illustrates a composite lens for composite eyewear

  of a pair of laminated plastic half-lenses 21 and 22 which are glued to each other at the mating surfaces 21a and 22a of respective half-lenses 21 and 22 The lightly colored transparent film 14 is formed on the mating surface 21a of the half-lens 21 by the sprayer 13 (FIG. 1) The other half-lens 22 is glued to the colored transparent film 14 applied to the mating surface 21a of the half-lens 21, thanks to

of a suitable adhesive.

  In the composite lens illustrated in FIG.

  of colored transparent film 14 is arranged between the half-lenses

  21 and 22, and therefore is not exposed Accordingly, even if the half-lenses 21 and 22 are glued to each other just after the formation of the colored transparent layer 14 on the jointing surface (by For example, the joining surface 21 a) of a half-lens (for example the half-lens 21) of the pair of half-lenses 21 and 22, the colored transparent layer 14 does not

  does not separate from the mating surface 21a of the half-lens 21.

  The color samples are preferably displayed in the eyeglass shop so that the consumer can choose a color Once his choice is made, the eyeglass lens can be immediately colored to the chosen color, using the sprayer 13 enclosing the eyeglass. selected coloring agent The coloring process according to the present invention exhibits more

  advantages in the choice of colors and their

  producibility (ie their match to the sample) is simpler and more suitable for mass production than

  the coloring process of the prior art.

  Although the present invention is particularly advantageous

  when the half-lenses 21 and 22 are made of a

  non-porous plastic material, not allowing the particles to penetrate

  dyeing, the present invention can be applied to a

  porous plastic optical element In addition, the pre-

  This invention can also be applied to a glass lens.

Claims (10)

  1 Method of coloring a transparent optical element   coating a predetermined surface of the transparent optical element with a coloring agent to form a layer of   colored transparent film (14) on this surface.   The staining method according to claim 1, wherein the   said transparent optical element is a lens (1 1) for your.   The staining method according to claim 2, wherein   said lens for glasses is a composite lens made of   two laminated half-lenses (21, 22) glued to each other   to respective mating surfaces (21a, 22a).   The staining method according to claim 3, wherein   said colored clear film layer (14) is first formed on the mating surface (21a) of a half-lens (21) of said pair of half-lenses, and then the other half-lens (22) ) is bonded to the colored clear film layer (14) formed on the surface jointing (21 a).   A coloring process according to claim 1, wherein the   staining is carried out by spray coating,   garment by rotation or dip coating.   The staining method according to claim 1, wherein the coloring agent is sprayed from a sprayer (13)   wherein the coloring agent is enclosed.   The method of coloring according to claim 1, wherein   the coloring agent contains permeate pigment particles   colored, whose average diameter is less than at 1 micrometer.   The staining method according to claim 1, wherein   the coloring agent contains permeate pigment particles   colored, whose average diameter is less than at 0.5 micrometer.   The method of coloring according to claim 1, wherein   the coloring agent contains dye particles.   A coloring process according to claim 1, wherein the transparent optical element is made of a plastic which does not leave   not penetrate the dye molecules of the coloring agent.   The method of coloring according to claim 1, wherein   the transparent optical element is made of glass.   The staining method according to claim 1, wherein a plurality of sprays (13) containing different agents   staining are prepared for use as desired.