JPS62170134A - Cathode ray tube - Google Patents

Abstract

PURPOSE:To prevent generation of sparkle so as to obtain an image of high quality, by using combined substance comprising unsaturated polyester as the main agent of adhesive, styrene or one kind of styrene derivant as bridging agent and one kind of unsaturated ester as another bridging agent, in a cathode ray tube in which a glass plate is attached to the front face of a face plate part via an adhesive. CONSTITUTION:Non-reflective glass 4 is adhesively set on the front face of the face plate part 2 of a cathode ray tube body 1, by means of an adhesive 3' made from unsaturated polyester resin including about 70wt% of unsaturated polyester serving as main agent, about 20wt% of styrene serving as the first bridging agent and about 10wt% of unsaturated ester serving as the second bridging agent. Since any difference in refractive index between main agent and bridging agent is eliminated by using an adhesive of such composition and sparkle can be certainly prevented from being generated, an image of high quality can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a cathode ray tube, and more particularly to a cathode ray tube in which a non-reflective transparent front panel is bonded to the front surface of a face plate of a cathode ray tube body.

[Conventional technology]

Conventionally, this kind of non-reflective transparent plate adhesive type cathode ray tube has a non-reflective transparent plate attached to the front surface of the face plate of the cathode ray tube body through an adhesive such as unsaturated polyester resin, epoxy resin, or silicone resin. A plate, generally made of glass, has a curved surface almost the same as the curved surface of the face plate, and has a non-reflective transparent plate (hereinafter referred to as front non-reflective glass) with anti-reflection treatment applied to one side. , the non-reflection treated surface is adhesively arranged in a direction that does not face the adhesive.

The structure of a cathode ray tube in which a glass plate is attached to the front surface of the face plate portion via an adhesive is described in detail in, for example, Meiko No. 48-42528.

[Problem that the invention seeks to solve]

However, in cathode ray tubes configured in this way, if an unsaturated polyester resin (the main resin is unsaturated polyester and the crosslinking agent is styrene) is used as the adhesive, the cost of the adhesive will be low, but the Resin viscosity is approximately 6P
Because it exceeds C8l and is difficult to mold, it is necessary to set the preheating temperature of the resin and face grate high. On the other hand, the viscosity can be lowered by increasing the amount of styrene added, but when the amount of styrene added increases, it polymerizes alone in addition to reacting with the unsaturated polyester main chain to produce polystyrene. However, the refractive index of the cured polyester resin is in the range of 1.50 to 1.54, or the refractive index 1r1 of polystyrene is 1.55 or more, resulting in a difference in refractive index between the two. As a result,
When a cathode ray tube is operated and the fluorescent surface emits light, this difference in refractive index causes the screen projected on the front non-reflective glass to sparkle (C8parkle), reducing image quality. That's the next problem.

However, if the viscosity of the unsaturated polyester is completely lowered by lowering its molecular weight, the adhesive force will decrease and the front non-reflective glass will easily peel off. Furthermore, when an epoxy resin is used as an adhesive, the cost of the adhesive is high, and there are frequent problems in that the adhesive turns rainbow yellow when exposed to ultraviolet light after long-term use, degrading image quality.

However, when a silicone resin is used, there are many problems in that the cost is high and the front non-reflective glass easily peels off because the silicone resin has hygroscopic properties.

The present invention was made in view of these circumstances, and its purpose is to prevent the generation of sparkles by specifying all the main ingredients and crosslinking agents that make up the adhesive, and to develop a cathode ray tube that can produce high-quality images. It depends on providing.

[Next method to solve all problems]

The cathode ray tube according to the present invention uses a combination of an unsaturated polyester as the main adhesive, styrene or one type of styrene derivative as the crosslinking agent, and one type of unsaturated ester as the other crosslinking agent. Ruru.

The crosslinking agent used in the present invention is a mixture of styrene or one type of styrene derivative as the yKl crosslinking agent and unsaturated ester type 11 as the second crosslinking agent. As the second crosslinking agent, as mentioned above, the following saturated esters such as fumaric acid ester, methacrylic ester, etc. are effective, and the fumaric ester used is diptyl fumarate, and the acrylic ester used is methyl methacrylate, etc. can.

1+1, the mixing ratio of the first crosslinking agent and the second crosslinking agent is preferably 1 = 1 to 2:1 in molar ratio, and the total ratio of the main agent to the crosslinking agent is 60 to 80 wt%, The content of the crosslinking agent is preferably 20 to 40 wt%.

[Effect]

The first crosslinking agent and the second crosslinking agent alternately react and copolymerize, thereby preventing the first crosslinking agent from becoming a single polymer.

[Embodiments of the invention]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a sectional view of essential parts showing an embodiment of a cathode ray tube according to the present invention. In the figure, a fluorescent surface 1b is provided on the inner surface of a panel 1a, and a shadow mask 1c and an electron gun assembly 1d are provided opposite to the fluorescent surface 1b. has a nearly constant dimension y = a, over the entire circumference.

Between mm [! Anti-reflective glass 4 is disposed facing each other through the gap G, and about 70% of unsaturated polyester is used as the main material in this gap G.
0 wt%, about 20 wt% styrene as the first crosslinking agent.
and an unsaturated ester (refractive index:
1.40 to 1.50) is filled and cured, and a non-reflective glass 4 is bonded and disposed using a cross adhesive 3'. In this case, diptyl fumarate (refractive index: 1.45) among fumaric acid esters is suitable as the unsaturated ester.

In this construction, the adhesive 3' is made of unsaturated polyester (refractive index: 1.50) as a main ingredient.

Styrene (refractive index: 1.54) as the first crosslinking agent and diptyl fumarate (refractive index: 1.54) as the second crosslinking agent.
45) is formed by filling and curing unsaturated polyester resin containing F. It prevents the polymerization of only styrene alone, that is, polystyrene (refractive index: 1.55 or more)
This prevents the formation of styrene and dibutyl fumarate, resulting in polymerization of styrene and dibutyl fumarate. In this case, the relative reactivity ratio of fumarate ester with styrene is r+ < 0.5, rz
< 0.3 Demeri, fumaric acid varnish, chill and styrene tend to react alternately, especially diptyl fumarate, r,
= 0.06, it will not be polymerized alone and will certainly be copolymerized alternately with styrene. As a result, the refractive index of the polymer of styrene and dibutyl fumarate was approximately 1.504.
The refractive index is adjusted to a value close to the refractive index of unsaturated polyester, which is 1.50. Back down, glue 3
The difference in the refractive index within the range is eliminated, and the generation of sparkles caused by this difference in refractive index can be reliably prevented.

In this intersection, the content of dibutyl fumarate in the second crosslinking agent is such that the overall refractive index of the adhesive 3' is 1.48 to 1.5.
Select as appropriate so that it falls within the range of 3. That is, if the refractive index of the adhesive 3' is less than 1.48, the adhesive 3' becomes cloudy, and if the refractive index exceeds 1.53, the aforementioned nine sparkles occur. Accordingly, the content of diptyl fumarate in the second crosslinking agent is fully adjusted so that the entire refractive index of the adhesive 3' is in the range of 1.48 to 1.53. This content is the first crosslinking agent and the second crosslinking agent.
The mixing ratio of the crosslinking agent with diptyl fumarate is 1
:1 to 2:1 is preferable, and the ratio of It, the total base resin to crosslinking agent is 60 to 80 wt% of the base resin and 20 to 40 wt% of the crosslinking agent.
t% is desirable. By adjusting this, the refractive index of the adhesive 3' is adjusted within the range of 1.50 to 1.51, and a cross-linking adhesive 3' with stable quality can be obtained, and especially when the refractive index is 1.504, it is extremely difficult to drag. A good effect can be obtained. In addition, the addition of diptyl fumarate to the adhesive 3' reduces the viscosity of the adhesive before curing, further improves the adhesive strength after curing, and enables adhesive curing with stable quality. Wider margin when working. '! Friend, in such a configuration, adhesive 3
If the thickness of the adhesive 3' is approximately 3.0 mm, but the thickness of the adhesive 3' is less than approximately 1.5 mm, the adhesive force will be insufficient.
The non-reflective glass 4 is likely to peel off, and problems also remain in terms of reinforcing strength. On the other hand, its thickness is about 5.0 m
If it is more than m, misalignment of the non-reflective glass 4 and leakage of the adhesive during injection are likely to occur. Therefore, the thickness of the adhesive 3' is preferably in the range of 1.5 to 5.0 mm, and by setting the thickness in the range of 2.5 to 4.0 mm, stable quality can be achieved. and productivity is obtained, especially its thickness'f 3. By setting it to Omm, an extremely good effect can be obtained.

In the above-mentioned example, dibutyl fumarate among fumaric esters was used as the unsaturated ester used as the crosslinking agent for M2, but methacrylic acid among acrylic esters was used as this type of unsaturated ester. Even if methyl is used, exactly the same effect as described above can be obtained. In this case, the adhesive 3' contains about 70 wtJ of unsaturated polyester as the main ingredient and about 15 wtJ of styrene I as the first crosslinking agent.
t%.

It is formed by filling and curing an unsaturated polyester resin containing about 15 wt % methyl methacrylate as a second crosslinking agent.

Next, a method for manufacturing the cathode ray tube constructed as described above will be explained.

FIG. 2 and FIG. 3 are detailed diagrams for explaining the method of manufacturing a cathode ray tube according to the present invention, and the same parts as in the previous figures are given the same reference numerals. First, as shown in FIG. 2, a spacer 5 is placed on the periphery of the face plate portion 20 with the face plate portion 2 of the cathode ray tube body 1 facing upward, and a gap p3F=3.0 mm is placed on the spacer 5. A non-reflective glass 4 is disposed facing the face plate portion 2 via the anti-reflection glass 4.

Next, this non-reflective glass 4 and the panel 1a of the cathode ray tube body 1
A tape 6 made of a synthetic resin material is wrapped around that surface and temporarily fixed. At this time, an injection lower portion connected to the gap G formed between the non-reflective glass 4 and the face plate portion 2 is provided in a part of the tape 6. Next, this cathode ray tube main body 1 is preheated to a temperature in the range of 40 to 60°C, and a resin liquid 9 having a composition described later and a second resin liquid housed in a first container 8 are heated as shown in FIG. While heating the curing agent 11 housed in the container 10 to about 40° C., a predetermined amount of the hardening agent 11 is supplied into the dispenser 12 and thoroughly stirred in the mixer 13 to form an adhesive liquid. Then, inject into the back 9 injection port T, and after filling, seal this injection lower hole. In this case, the viscosity of the adhesive before curing is approximately 2.5PC at 25°C.
Adjust to 8.

Next, the entire cathode ray tube body 1 is heated and filled at about 60° C., which is higher than the preheating temperature F, for about 3.0 hours to harden the constant contact layer liquid and bond the non-reflective glass 4. After that, the excess portion of the injection lower machining tape 6 is removed to complete the process.

[Adhesive liquid composition I]

(Resin liquid) (1) Unsaturated polyester 70wt% (
2) Styrene 2(hrt%(
3) Dibutyl fumarate 10vrt% (
Curing agent] (4) Methyl ketone peroxide 2wt% (
Permec N: Product name) l) - (3) Based on the total amount] [Adhesive liquid composition ■] (Resin liquid) (1) Unsaturated polyester 70wt%
(2) Styrene 15wt%<
3) Methyl methacrylate 15wt% (curing agent) (4) Methyl ketone peroxide 2vt% (
Vermec N: Product name) l) - (3) For the amount of a] If this manufacturing method is used, non-reflective glass 4 can be produced using the manufacturing process of injecting and curing ordinary unsaturated polyester resin can be easily adhesively cured with respect to the two surfaces of the face plate portion at a constant interval, and since the properties of the adhesive, particularly the adhesive strength properties, do not change significantly, sufficient adhesive strength can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, an unsaturated polyester is used as the main material, styrene or one type of styrene derivative is used as the crosslinking agent, and an unsaturated ester is used as the other crosslinking agent. Since there is no refractive index difference between the two and the sparkles can be reliably prevented from occurring, high-quality images can be obtained. In addition, since the non-reflective glass can be reliably bonded to the face grate at regular intervals, it is possible to produce cathode ray tubes of high quality and reliability at low cost and with high productivity. is obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of essential parts showing an example of a non-reflective glass-bonded cathode ray tube according to the present invention, and FIGS. Illustrated. 1...Cathode ray tube body, 2...Face grate, 3'...Adhesive, 4...-Non-reflective glass,
5...Spacer. ,・′,−≧＼ Agent Patent attorney Katsuo Ogawa 6′]・′′x＼
, ・Nee- Fig. 1 1 ・Pfu
Country B

Claims (1)

[Scope of Claims] 1. A tube body having a face plate at one end, a non-reflective transparent plate placed in front of the face plate of the tube body at a predetermined gap, and a cross-linked tube body mainly made of unsaturated polyester. An unsaturated polyester resin containing styrene or one type of styrene derivative as an agent and an unsaturated ester as another crosslinking agent is filled in the gap to fix the tube body and the non-reflective transparent plate. Equipped with a cathode ray tube. 2. The cathode ray tube according to claim 1, wherein the unsaturated ester is a fumaric acid ester. 3. The cathode ray tube according to claim 1, wherein the unsaturated ester is an acrylic ester or a methacrylic ester.