KR100464760B1 - Plastic mirror for the use of car and the method thereof - Google Patents

Abstract

The present invention relates to a plastic mirror for automobiles and a method for manufacturing the same. Reflective layer 13 in which aluminum, silver, chromium or a mixture thereof is deposited on one surface of the rear surface, and reflectance control layers 14 and 15 in which titanium oxide (TiO ₂ ) and silicon oxide (SiO ₂ ) are sequentially deposited on the entire surface of the substrate layer. ), A plastic mirror for automobiles comprising a second hard film layer 16 coated on both sides of the substrate layer with the same hard coating solution as the first hard coating solution, and a third hard film layer 17 coated on both sides of the substrate layer with a silicone-based hard coating solution. And to a method of manufacturing the same.

In addition, in the present invention, a hard film may be formed on the reflectance control layers 14 and 15 by using plasma chemical vapor deposition.

Description

Plastic mirror for automobile and its manufacturing method {Plastic mirror for the use of car and the method

The present invention relates to a surface-reinforced plastic mirror used in automobiles and a method of manufacturing the same.

Commonly used automotive mirrors can be roughly divided into prism type rear mirror glass mirror and flat front mirror glass mirror.

The prism rear mirror glass mirror is formed on the back of the base material with silver, aluminum, etc., and is then coated with an organic coating. The surface of the base material itself is a good reflector, but the glass itself has a thickness and thus cannot be simply reflected. Therefore, the light partially transmitted from the reflective surface is refracted only by the glass thickness, and multi-reflection occurs due to the reflection from the rear surface. As a result, there is no single phase point but multiple overlapping multiple phases. In addition, since only the surface reflection of the front surface of the prism mirror occurs when adjusting the angle to prevent glare during night driving, there is a problem that the reflectance drops sharply.

Flat mirror glass mirrors are made by depositing chromium and metal oxides on the entire surface of the base material.The glass base material is weak in impact resistance, and as the metal or metal oxide layer is exposed to the air, color is formed on the surface and the reflectance is increased. Falls. In addition, since the stain resistance is bad, it does not erase well, so the fatigue of the driver's eyes increases, which adversely affects eyesight.

Such glass mirrors are very weak in impact resistance and have a problem of causing fatal damage or damage to the human body when broken.

Therefore, plastic mirrors have emerged as a countermeasure to solve the above problems.

Most plastic mirrors are back mirrors, which form a reflective film on one surface of both sides of a polymer synthetic resin, and then dip it into a hard coating liquid or form a hard coating film by spraying. And two methods of sequentially forming and manufacturing a reflective film and an organic protective film.

However, since the plastic mirror directly deposits the metal on the organic substrate without the first hard coating layer on the surface of the plastic substrate, the organic-inorganic bond is not formed, so the adhesion is very poor, and there is no metal oxide layer or ceramic layer. As time passes, the change in time occurs and the reflectance becomes significantly worse. In addition, absorption crystallization, stress relaxation and deformation appear during the stabilization state, the smoothness is not maintained, and because of eye fatigue, there is a problem that is unsuitable as an automotive mirror in terms of precision of the surface shape accuracy.

The present invention has been made to solve the above problems, an object of the present invention is to provide an automotive plastic mirror having high impact resistance, excellent smoothness and surface waveform value using a thermoplastic and thermosetting polymer resin substrate, and a manufacturing method thereof. .

1 is a view showing a manufacturing process of a plastic mirror for an automobile according to a preferred embodiment of the present invention.

2 is a cross-sectional view of a plastic mirror (front mirror, rear mirror) for an automobile manufactured according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

11 substrate layer 12 primary hard film layer

13: reflective layer 14: titanium oxide reflectivity adjusting layer

15 silicon oxide reflectance control layer 16 secondary hard film layer

17: 3rd hard film layer

The present invention relates to a surface-reinforced plastic mirror used in automobiles and a method of manufacturing the same.

The plastic mirror for automobiles of the present invention is a thermoplastic and thermosetting polymer synthetic resin substrate layer 11, the first hard film layer 12 coated on both sides of the substrate layer with an acrylic or silicon-based hard coating solution, aluminum, silver on one side of the front or rear surface of the substrate layer , The reflective layer 13 on which chromium or a mixture thereof is deposited, the reflectance control layers 14 and 15 on which titanium oxide (TiO ₂ ) and silicon oxide (SiO ₂ ) are sequentially deposited on the entire surface of the substrate layer, The secondary hard film layer 16 coated with the hard coating liquid of the same component as the primary hard coating liquid and the third hard film layer 17 coated with the silicon-based hard coating liquid on both sides of the substrate layer.

The manufacturing method of the plastic mirror for automobiles of the present invention

(a) forming a thermoplastic and thermosetting polymer resin substrate layer;

(b) coating both sides of the substrate layer with a primary dip-hard coating method with an acrylic or silicon-based hard coating solution;

(c) selecting and depositing one of aluminum, silver, chromium, or a mixture thereof on one of the front and rear surfaces of the substrate layer;

(d) sequentially depositing titanium oxide and silicon oxide over the substrate layer;

(e) coating both surfaces of the substrate layer with a second dip-hard coating method with a hard coating solution of the same component as the first hard coating solution; And

(f) tertiary coating on both sides of the substrate layer with a silicon-based hard coating solution.

In step (f) of the present invention, 1) forming a tertiary hard layer by dip-hard coating after alkali activation or plasma surface cleaning, or 2) plasma enhanced chemical vapor without alkali activation or surface cleaning. and forming a tertiary hard film layer using a deposition method.

In addition, the present invention is characterized in that the hard film layer is formed on the reflectance control layers 14 and 15 by using a plasma chemical vapor deposition method.

Referring to the accompanying drawings, the manufacturing method of the front mirror plastic mirror of the present invention is as follows.

1 is a view showing a manufacturing process of a plastic mirror for a vehicle according to a preferred embodiment of the present invention, Figure 2 is a cross-sectional view of a plastic mirror for the automobile (front mirror, rear mirror) manufactured by an embodiment of the present invention.

The plastic mirror for automobiles of the present invention forms the polymer synthetic resin substrate layer 11 by extrusion, injection compression molding or casting molding according to the mirror shape and application. The substrate layer 11 is made of thermoplastic and thermosetting polymer resin such as polymethyl methacrylate, polycarbonate, polyether sulfone, and the like.

Both surfaces of the substrate layer 11 are coated with a primary dip-hard coating method using an acrylic or silicon hard coating solution, and cured by a thermal curing and UV curing method to form a primary hard film layer 12 having a thickness of about 2 to 5 μm. do. This increases the surface hardness, wear resistance, and surface waveform values of the plastic.

On one side of the primary hard film layer 12, one of aluminum, silver, chromium or a mixture thereof is selected and deposited by vacuum deposition to form the reflective layer 13.

The reflectance control layers 14 and 15 are formed by sequentially depositing titanium oxide and silicon oxide on the reflective layer 13 which change the reflectance of the reflective layer according to the change over time and vary the refractive index according to the thickness.

Since the metal oxide layer is gradually oxidized by oxygen and other corrosive components present in the air, a hard coating liquid having the same composition as that of the primary hard coating liquid on the silicon oxide reflectivity adjusting layer 15 is used to increase interlayer adhesion and oxidation resistance. It is coated by a second dip-hard coating method and cured by a thermosetting and ultraviolet curing method to form a second hard film layer 16 having a thickness of about 2 to 5 μm.

In order to increase the interlayer adhesion, surface hardness and scratch resistance of the plastic mirror, the surface of the substrate is modified by alkali activation treatment or plasma surface cleaning after the second dip-hard coating.

After the surface treatment process, the third hard film is coated on the secondary hard film layer 16 by using a third hard-coating solution and cured by a thermosetting method to form a third hard film layer 17 having a thickness of about 2 to 5 μm. . However, when the polymethyl methacrylate (PMMA) material is used as the substrate, the tertiary hard film layer 17 may be omitted.

In addition, when the surface treatment process is not performed, the third hard film layer 17 is formed by using plasma enhanced chemical vapor deposition.

In the plasma chemical vapor deposition method, an organic silicon compound is introduced into a plasma in a gaseous state and decomposed into a reactive gas which flows together to form a high wear resistant material on the reflective layer of the plastic mirror. The thin film may be manufactured at a relatively low temperature (100 ° C. or lower) by supplying energy required for the reaction through a plasma. In addition, it is possible to obtain a thin film (metal, semiconductor, compound) of various compositions, there is an advantage that can easily adjust the stoichiometry.

The manufacturing method of the rearview mirror for automobiles of the present invention only deposits the reflective layer 13 on the rear side, and the other methods are the same as the manufacturing method of the frontview mirror.

The primary and secondary silicone-based coating agents used in the present invention are characterized by increasing the adhesion between the plastic substrate and the metal oxide layer due to the amount of organic matter added, and the tertiary silicone-based coating agent is a special inorganic filler for increasing scratch resistance and special UV absorbers are contained. In particular, the inorganic filler added to the tertiary hard coating agent is modified with other organic materials, so that it is more chemically bound to the silicone resin, so the surface hardness and scratch resistance are very excellent.

Hereinafter, exemplary embodiments of the present invention will be described in detail, but the present invention is not limited thereto.

Example 1 : Primary hard film layer 12 formed

The polymer synthetic resin substrate layer was molded according to the mirror shape.

The molded substrate layer 11 is cleaned and dried ultrasonically in a 5-6% alkaline cleaning solution at 50-60 ° C. for 5-10 minutes, and thereafter, after removing dust or foreign substances with an antistatic gun in a clean room, a dip coating bath (Dip-Coater) ) Perpendicular to the jig.

The dip coating bath containing the primary hard coating solution was raised at a constant rate, and the coating solution was deposited on the surface of the substrate layer 11 and maintained for 10 seconds.

The dip coating bath was lowered at a constant speed (2 to 4 mm / sec) to uniformly apply the coating solution to the substrate surface.

In the case of UV-curable coatings, after pre-heating for 3 to 5 minutes at 50 ~ 60 ℃ after immersion, UV cured at a transfer speed of 3 ~ 10m / sec with an ultraviolet mercury lamp of 1.5 ~ 3㎾.

In the case of a thermosetting coating agent, after leaving for 10 minutes at room temperature after deposition, the substrate was placed in a hot air dryer and cured at 85 to 125 ° C. for 1 to 2 hours.

Humidity was 50% or less (relative humidity) and the temperature of the coating liquid was maintained at 18-20 degreeC.

Example 2 : Deposition of Reflective Layer 13

The plastic substrate on which the primary hard film layer 12 is formed is mounted in a jig, loaded into a load lock chamber, and then transferred to the main chamber to inject argon gas to inject argon gas, thereby cleaning the ion. cleaning).

In order to obtain a uniform film using a metal having high reflectivity (Al, Ag, Cr) in an atmosphere of vacuum degree of 6.0 × 10 ^-6 Torr, the jig was deposited to a thickness of about 60 to 100 nm while reciprocating the left and right.

The deposition conditions are E-Gun emission current of 40 ~ 580 ㎃, deposition rate of 0.3 ~ 2.5nm / sec.

Example 3 : Deposition of titanium oxide reflectance adjusting layer 14 and silicon oxide reflectivity adjusting layer 15

Titanium oxide (TiO ₂ ) and silicon oxide (SiO ₂ ) are injected with oxygen gas (O ₂ gas) in a vacuum degree of 4.5 × 10 ^-5 Torr atmosphere, while the titanium oxide reflectivity control layer 14 is 10-30 nm, silicon oxide reflectance. The adjusting layer 15 was deposited to a thickness of about 50-100 nm.

Deposition conditions are the same as those of Example 2 above.

Example 4 : Second Hard Film Layer 16 Formation

It apply | coated like the method of Example 1 using the thermosetting coating liquid, and it hardened in the hot air dryer.

The curing condition of the thermosetting coating liquid is 45 to 120 minutes at 85 ~ 125 ℃.

Example 5 Surface treatment process

In order to surface-treat the secondary hard film layer 16 formed by the fourth embodiment, an alkaline solution activation process or a plasma surface cleaning method may be selectively used.

1) Alkali solution activation treatment

The substrate on which the secondary hard film layer 16 was formed was immersed in a 5-10% sodium hydroxide (NaOH) aqueous solution at 50-60 ° C. for 5-10 minutes, washed with distilled water, and dried.

2) Plasma surface cleaning method

The plasma surface cleaning system was used for 3 minutes while injecting 50 sccm of argon gas and 50 sccm of oxygen gas under conditions of a vacuum degree of 9 × 10 ⁻³ Torr and a power of 700 W.

Example 6 : Tertiary hard layer 17 formed

Silicon-based was used as the third hard coating agent for immersion, the coating method and the curing conditions were the same as the secondary thermal curing conditions.

After the surface treatment process was carried out in Example 5, a third hard film layer was formed by a dip-hard coating method.

Alternatively, after forming the secondary hard film layer 16 according to Example 4, the tertiary hard film layer 17 was formed by using a plasma chemical vapor deposition method without performing a surface treatment process.

Example 7

The hard film was formed on the titanium oxide reflectance control layer 14 and the silicon oxide reflectance control layer 15 according to Example 3 using a plasma chemical vapor deposition method.

In order to coat the SiOx (x = 1 ~ 2) thin film, organic silicon-based compounds such as tetraethyl orthosilicate and hexamethyldisiloxane are introduced into a gaseous state through a bubbler and are abrasion resistant under the following conditions. The thickness of the film was formed at 400-1500 nm.

The conditions of the plasma chemical vapor deposition method are the bubbler temperature 70 ℃, the tube temperature 40 ℃ of the bubbler and the chamber, the chamber temperature 30 ℃, the carrier gas (Ar) flow rate 10 sccm, the reactive gas (O) ₂ ) The flow rate is 160 sccm, base pressure 30 mtorr, working pressure 600 mtorr, RF power 400W and deposition time 10 ~ 60 minutes.

Plastic mirrors for automobiles of the present invention can be used as a replacement for glass mirrors for automobiles by obtaining a very good wear resistance and surface waveform values.

According to the present invention, the plastic material can be used to improve safety, reduce weight, and use a wide range of materials. In addition, it has excellent molding processability, and sufficient functionality is secured, so that it is possible to replace expensive automotive electrochromic mirrors, and materials can be recycled.

The plastic rearview mirror for automobiles of the present invention is coated with a metal oxide layer having a high refractive index on the surface layer, and an optical hard coating film is formed on the upper layer to increase the surface reflectivity by about 80 to 150% compared to the glass mirror. In addition, the metal oxide layer may prevent the driver's glare by weakening it even when strong light such as a headlight of the rear vehicle comes from the rear during the night driving.

Claims (10)

A polymer synthetic resin substrate layer 11, a primary hard film layer 12 in which both surfaces of the substrate layer are dip-coated with an acrylic or silicon hard coating solution, a reflective layer 13 in which aluminum, silver, chromium or a mixture thereof is deposited on the entire substrate layer; Reflectivity control layers 14 and 15 in which titanium oxide (TiO ₂ ) and silicon oxide (SiO ₂ ) were sequentially deposited on the entire surface of the substrate layer, and two surfaces of both sides of the substrate layer were dip-coated with the same hard coating solution as the primary hard coating solution. A front mirror plastic mirror for automobiles, comprising a third hard film layer 17 in which both the car hard film layer 16 and the substrate layer are dip-coated with a silicone-based hard coating solution. A polymer synthetic resin substrate layer 11, a primary hard film layer 12 in which both surfaces of the substrate layer are dip-coated with an acrylic or silicon hard coating solution, a reflective layer 13 in which aluminum, silver, chromium or a mixture thereof is deposited on the back of the substrate layer, Reflectivity control layers 14 and 15 in which titanium oxide (TiO ₂ ) and silicon oxide (SiO ₂ ) were sequentially deposited on the entire surface of the substrate layer, and two surfaces of both sides of the substrate layer were dip-coated with the same hard coating solution as the primary hard coating solution. Automobile rear mirror plastic mirror, characterized in that consisting of the third hard film layer 17 of the car hard film layer 16 and both sides of the substrate layer deep coating with a silicone-based hard coating liquid The plastic mirror for automobiles according to claim 1 or 2, wherein the thicknesses of the first, second and third hard film layers are about 2 to 5 µm. A method of manufacturing a plastic mirror for an automobile, the method comprising: (a) forming a polymer synthetic resin substrate layer; (b) coating both sides of the substrate layer with a primary dip-hard coating method with an acrylic or silicon-based hard coating solution; (c) selecting and depositing one of aluminum, silver, chromium or a mixture thereof over the substrate layer; (d) sequentially depositing titanium oxide and silicon oxide over the substrate layer; (e) coating both surfaces of the substrate layer with a second dip-hard coating method with a hard coating solution of the same component as the first hard coating solution; And (f) tertiary deep coating on both sides of the substrate layer with a silicon-based hard coating solution. A method of manufacturing a plastic mirror for an automobile, the method comprising: (a) forming a polymer synthetic resin substrate layer; (b) coating both sides of the substrate layer with a primary dip-hard coating method with an acrylic or silicon-based hard coating solution; (c) selecting and depositing one of aluminum, silver, chromium or a mixture thereof on the backside of the substrate layer; (d) sequentially depositing titanium oxide and silicon oxide over the substrate layer; (e) coating both surfaces of the substrate layer with a second dip-hard coating method with a hard coating solution of the same component as the first hard coating solution; And (f) tertiary deep coating on both sides of the substrate layer with a silicon-based hard coating solution. The vehicle plastic according to claim 4 or 5, wherein the substrate layer is formed by extrusion, injection compression molding or casting molding in step (a). How to make a mirror The method of manufacturing a plastic mirror for an automobile according to claim 4 or 5, wherein the vacuum deposition is performed in the steps (c) and (d). The method of manufacturing a plastic mirror for automobiles according to claim 4 or 5, wherein a tertiary hard film layer is formed by a dip-hard coating method after alkali activation treatment or plasma surface cleaning before step (f). delete delete