KR100314881B1 - Polyolefin-based hot melt adhesive for deflection yoke - Google Patents

Abstract

The present invention relates to a hot-melt composition for deflection yoke, specifically, 5 to 25% by weight of a wax component of polyethylene or polypropylene, 25 to 40% by weight of a rosin-based adhesive component resin, 10-50% by weight of ethylene propylene copolymer-based base polymer, 1-10% by weight of styrene-based copolymer or block copolymer rubber, and is selected from fillers, plasticizers, antioxidants, flame retardants, and color pigments. It relates to a hot-melt composition for deflection yoke, further comprising at least one component. The hot melt composition of the present invention has a cold resistance, heat resistance, high meltability, and high temperature stability as compared with a conventional hot melt mainly composed of polyamide by optimizing the type and content of the adhesive component resin, base polymer, rubber, etc. in addition to polyolefin as a main component. And it is excellent in adhesive force, and can be usefully used as an adhesive for deflection yoke used in televisions, computer monitors, and the like, which require high cold resistance, heat resistance, adhesion, flame retardancy, and thermal shock strength.

Description

Polyolefin-based hot melt adhesive for deflection yoke

The present invention relates to a hot-melt composition for deflection yoke, specifically, 5 to 25% by weight of a wax component of polyethylene or polypropylene, 25 to 40% by weight of a rosin-based adhesive component resin, 10-50% by weight of ethylene propylene copolymer-based base polymer and 3-10% by weight of styrene-based copolymer or block copolymer rubber are selected as main components, and selected from fillers, plasticizers, antioxidants, flame retardants, and color pigments. It relates to a hot-melt composition for deflection yoke, characterized in that it further comprises at least one component.

Deflection yoke is installed outside the rear glass of the cathode ray tube (CRT) to adjust the deflection angle of the electron beam irradiated from the electron gun. It consists of a deflection coil, a vertical deflection coil, and a ferrite core.

CRT is used as a CRT tube, which is a special vacuum tube that converts an electric signal into an optical image such as an image, a figure, or a character by the action of an electron beam. It is an oscilloscope, frequency analyzer, medical monitor for electric phenomenon or waveform observation. In addition to industrial CRT tubes such as CRTs used for observation, they are basically used as various image display apparatuses such as CRT tubes for TV receivers and CRT tubes for computer monitors. A commonly used CRT consists of a fluorescent film, a shadow mask, and an electron gun applied and printed on the inner surface of a panel of a glass container evacuated by high vacuum. The electron gun generates heat from the heater by an externally applied voltage to emit hot electrons of the cathode ray, thereby controlling, accelerating, and focusing the electrode to shoot an electron beam and emit light by emitting light on the fluorescent film. The electron beam made by the electron gun passes between two sets of deflection plates or deflection coils arranged at right angles to each other and is deflected by the signal voltage applied to the deflection plates or deflection coils from the outside to move the light points on the fluorescent surface up, down, left, and right. Painted. The deflection methods include electrostatic deflection that deflects the electron beam by an electric field and electron deflection that causes electric current to flow through the deflection coil installed in the neck of the CRT. The deflection angle is smaller than the electron deflection. Because of its high frequency, it is widely used in observation CRTs.

Among the components of the deflection yoke, the vertical deflection coil creates a magnetic field in the left and right directions to deflect the electron beam in the vertical direction, and the horizontal deflection coil creates a magnetic field in the vertical direction in order to deflect the electron beam from side to side. The operating frequency of the vertical deflection coil is about 60 to 70 KHz, but the horizontal deflection coil was only about 15 KHz in general-purpose TVs, and in the case of recent high-definition TVs, a high frequency of about 48 KHz is used. Computer monitors that require long resolutions and high resolutions operate at a very high frequency of about 110 KHz. Therefore, deformation of the deflection yoke and change of screen characteristics due to temperature rise have become a big problem. . In addition, as the use of CRTs is widely used in tropical and cold climates, as well as in areas with extreme climatic conditions such as dry or wet areas, high cold resistance, heat resistance, adhesiveness, flame retardancy, and thermal shock strength are attracting attention as important properties of the deflection yoke.

In the deflection yoke, hot melt is an adhesive used to bond and fix the vertical deflection coil, the horizontal deflection coil, and the ferrite core. Hot melt adhesive is a solvent-free adhesive with a solid content of 100% at room temperature, which is heated and melted when used to apply to various adherends, and then cooled and solidified to express adhesive strength.It is widely used in the field of home appliances as well as packaging, bookbinding or wood processing. come. The hot melt is heated and melted at high temperature and cooled immediately after application to enable continuous operation. Since no volatiles are generated, the adjustment of the coating thickness is simple and uniform, and there is no risk of fire. Generally, a base polymer, an adhesive resin and a wax are used. Consists of three components, if necessary, antioxidants, plasticizers, flame retardants and the like are used in combination.

The main component is the most ethylene vinyl chloride copolymer (ethylene vinyl chloride copolymer, EVA), polyamide, polyester, atactic polypropylene, etc. have been used, rosin-based resin, petroleum resin as a tackifier to this And the like, and have been prepared by mixing waxes, antioxidants, inorganic fillers, reversible agents and the like.

Appearance has the shape of pallet, block, etc., and it is appropriately selected according to the usage and the place of use.As it adheres soon after the temperature decreases, the adhesion is usually within 1 second, so the continuous work is possible. The same applies to difficult vertical and inclined planes. It can also be used for materials that reach their highest strength shortly after cooling and cannot be bonded by common adhesives such as polyethylene and polypropylene.

However, conventional hot melt adhesives are commonly used in packaging, bookbinding, wood processing, electrical and electronic fields, and generally have problems in heat resistance, cold resistance, adhesiveness, flame retardancy, and thermal shock strength, which are disadvantages of hot melt. That is, the polyamide series, which is a main component of the conventional hotmelt, has a disadvantage in that the hotmelt has poor adhesiveness due to carbonization at a high temperature of 200 ° C. or higher, and also has a large characteristic change due to absorption in the polyamide series. The low density polyethylene used as the base material for the adhesive has very poor and poor low temperature characteristics due to the crystalline, and in the case of ethylene vinyl acetate, the crystallinity is reduced, but has a disadvantage of low compatibility with the compounding components. In addition, acrylic systems are inferior in terms of adhesion, peel resistance, and creep resistance, and can be used only in solution type and aqueous systems, and have high stability in amorphous polyolefin, but have poor balance due to inconsistency in grade, composition, and viscosity. There was a disadvantage of high loss of adhesion. In addition, amorphous polyolefins tend to have poor adhesion, low tensile strength, and leave a residue on the surface of the substrate after peeling due to the heterogeneity of the branch distribution and the broad molecular weight distribution. Therefore, a hot melt composition having excellent bonding strength has been developed using a relatively homogeneous linear ethylene / α-olefin interpolymer, but also made of polyolefin-based resin, which has low low-temperature adhesiveness, and requires high temperature during molding, resulting in unevenness in the foam. Occurred and showed poor adhesion.

In particular, such a known hot melt composition is mostly used in the paper or non-woven industry, or only for adhesion of automotive interior materials, and is satisfactory for deflection yokes that generate high temperatures such as CRTs or monitors that require high frequency operation. It did not exhibit as much cold resistance, heat resistance and thermal shock strength. Therefore, there has been an urgent need to develop a new hot melt composition having high temperature heat resistance, cold resistance, and thermal shock strength required as a deflection yoke in the electric and electronic field while satisfying general properties of the hot melt adhesive, that is, adhesion, workability, shock absorption, and flame retardancy.

Accordingly, the present inventors have cold resistance and heat resistance down to -40 ° C. or lower and 120 ° C. or higher, and have strong thermal resistance that does not show cracks and excitation even after repeated thermal shocks for several tens of low and high temperatures. Research has been conducted to develop a hot melt composition for the deflection yoke, and it is 5 to 25% by weight of a wax component of polyethylene or polypropylene; 25 to 40% by weight of an adhesive component resin of a rosin ester-based or rosin phenol copolymer; 10 to 50% by weight of the base polymer of the ethylene propylene copolymer series; The hot melt composition composed of 3 to 10% by weight of the rubber of the styrene-based copolymer or the block copolymer; satisfies the above-mentioned cold resistance, heat resistance and thermal shock strength, and also excellent in terms of continuous workability and ease of thickness control, etc. The present invention was completed by revealing.

It is an object of the present invention to provide a polyolefin type hot melt composition having excellent cold resistance, heat resistance and thermal shock strength.

In addition, it is an object of the present invention can be used in a CRT or monitor that has a good cold resistance, heat resistance, and thermal shock strength as described above, the deformation of the deflection yoke and the change in screen characteristics due to the high temperature heat generated by high frequency operation is likely to occur. It is to provide a hot melt composition for deflection yoke.

In addition, an object of the present invention is to provide a hot-melt composition for deflection yoke that can be continuously melted by heating and melting at a high temperature, cooled immediately upon application, and made of adhesive, and thus it is easy to control the application thickness evenly because no volatile matter is generated.

Figure 1 shows a specimen produced to test the cold resistance and thermal shock strength of the hot melt composition for DY of the present invention, by applying a hot melt to the junction of the pair of deflection yoke and the connection between the plastic plate and the deflection coil It is a schematic of the deflection yoke specimen produced,

A: Ferrite Core

B: plastic plate

C: Hot Melt Coating Area

D: deflection coil

E: Ferrite Joint Clip

Figure 2 is a schematic view showing the shape of the specimen prepared to measure the tensile adhesion strength of the hot melt composition for DY of the present invention, O on the A side is attached to the fixed portion, O on the B surface is attached to the push-pull gauge .

In order to achieve the above object, the present invention provides a hot-melt composition for deflection yoke based on polyolefin instead of polyamide.

Specifically, the hot melt composition of the present invention is 5 to 25% by weight polyolefin wax component, 25 to 40% by weight rosin-based adhesive component resin, 10 to 50% by weight polyolefin-based ethylene propylene copolymer base polymer, styrene-based copolymer rubber It consists of 1-10 weight%.

As the polyolefin wax component, it is preferable to use polyethylene or polypropylene wax, and heat resistance and melt viscosity can be adjusted by using 5 to 40% by weight of the polyolefin wax component. Moreover, workability can be improved by using a polyolefin wax component. If the wax component is too small at less than 5% by weight, it is difficult to control the melt viscosity, the workability is poor, and the delamination occurs. If too much wax or more than 40% by weight is used, there is a problem that the lowering of the adhesive strength and low temperature properties.

As the adhesive component resin, natural or synthetic resins such as rosin-based resins and terpene-based resins, derivatives thereof, and petroleum resins may be used. Especially, rosin ester-based hydrogenated resins or rosin phenol copolymer synthetic resins having a weight average molecular weight of 500 to 50,000 By using it, adhesive force can be improved. The rosin-based adhesive component resin is preferably used at about 25 to 40% by weight. By using rosin-based resin, the adhesion, cold resistance and heat resistance can be improved.

On the other hand, in order to increase the cold resistance and heat resistance, a polyolefin copolymer-based base polymer is used. As the base polymer, it is preferable to use an ethylene propylene copolymer having a weight average molecular weight of 500 to 50,000 and 10 to 50% by weight. Do. In particular, the ethylene propylene copolymer is preferably a melt viscosity of 3,000 to 8,000 cps, a softening point of 120 to 160 ° C., and a melt density of 0.7 to 0.8 g / cm 3. In addition, it is possible to improve flexibility, cohesion and adhesion by using a polyolefin-based base polymer.

Also, to improve cold resistance, rubber such as styrene butadiene random copolymer (SBR), styrene butadiene block copolymer (SBS), styrene ethylbutadiene copolymer (SEBS) It is preferable to use 1-10 weight%.

In addition, the hot-melt composition of the present invention is 10 to 40% by weight filler for impact absorption (plastic filler), 1 to 5% by weight plasticizer for improving flexibility and cold resistance, to maintain the stability of anti-denaturation by oxygen and UV in the air It may further comprise 0.1 to 2% by weight of antioxidant, 3 to 15% by weight of flame retardant, and 0.2 to 3% by weight of color pigment.

As the filler, calcium carbonate, talc, or the like may be used. Plasticizer refers to an organic composition added to a thermoplastic resin, rubber or other resin to improve extrudability, flexibility, processability or stretchability, paraffinic or naphthenic hydrocarbon oil, polybutene and the like can be used, in particular the present invention In phthalic acid system and polybutene system, it is preferable to use. Halogen, phosphate, and the like may be used as the flame retardant, and other antioxidants may be used. The additives are generally inert and do not affect the properties of the base polymers, waxes, tackifiers and rubber components, which are substantially the main ingredients, and are not limited to those listed above and are widely known to be used in conventional hot melts. All can be used to improve the performance of the hot melt composition of the present invention.

The manufacturing method of a hot melt adhesive is largely divided into the process of heat-melting and blending a blending raw material, and the process of shaping | molding and cutting to an appropriate form. As the molding form, pellets, chips, blocks, and films may be used. Particularly, in order to be applied to the deflection yoke of the present invention, it is preferable to be manufactured in the form of chips. It is not limited.

For the preparation of the hot melt composition of the present invention, the heat of the blend is first melted using a hot melt stirring tank. At this time, the hot-melting stirring tank is used in the capacity of 100 ~ 5,000ℓ capacity. Melting temperature shall be 100-250 degreeC or less, and a wax and antioxidant are first thrown in at the speed of 20-150 rpm, and it melt | dissolves, maintaining the temperature of 150-250 degreeC. Then, the rubber is added and melted, and then the adhesive component resin is added and melted to blend.

When the heat melting and blending of the main components is completed as described above, after dilution of the filler to improve the shock absorption and heat resistance of the product, the base polymer is added and dissolved. After the base polymer is completely melted, a plasticizer, a color pigment, and a flame retardant are sequentially added, followed by stirring for 30 to 60 minutes.

It manufactures in the form of a cooling chip | tip using a steel conveyor belt in the state which adjusted and maintained the internal temperature of the stirring tank to 150-250 degreeC.

In order to investigate the properties of the hot-melt adhesive for deflection yoke prepared using the hot-melt composition of the present invention, cold resistance, heat resistance, thermal shock strength, adhesiveness, and flame retardance were measured, respectively.

First, in order to investigate cold resistance, the hot melt of the present invention was melted to prepare a specimen and cooled to room temperature. The specimens were placed in a thermostat maintained at -20, -30 and -40 ° C for 168 hours and then taken out and examined visually for cracking and lifting. As a result, it was confirmed that the hot melt of the present invention does not generate any cracks or lifting phenomenon at all even at -40 ° C, and has cold resistance that can withstand at least -40 ° C or less.

In addition, in order to investigate the heat resistance, the hot melt of the present invention was placed in a crucible and left in a dry oven maintained at a high temperature for 24 hours, and then the degree of denaturation (carbonization) and precipitation formation were observed. As a result, the hot melt of the present invention was found to be very excellent in comparison with the conventional hot melt in terms of heat resistance because there is almost no modification and precipitation even at 200 ℃.

Thermal shock strength was measured by leaving the hot-melt specimens of the present invention in a constant temperature and humidity chamber for 1 hour by alternating low and high temperatures for 1 hour and then checking for cracking and lifting. The hot melt of the present invention did not generate any cracks and lifting phenomenon even when 50 times of temperature change (100 hours) were alternately performed at -40 ° C. for 1 hour and 110 ° C. for 1 hour, and thus the thermal shock strength was very high. I could confirm it.

The adhesive test measures the maximum load until the specimen is destroyed by placing the specimen in a 25 ° C. dry oven for 1 hour and then pulling it out with a pull pull gauge at a tensile speed of 10 mm / min within 10 seconds. By performing. As a result, the hot melt of the present invention exhibited a tensile strength of about 70 ~ 75 kgf / m ² compared to the known hot melt exhibiting a tensile strength of about 55 kgf / m ^{2 It} was confirmed that the hot melt is superior to the conventional hot melt in terms of tensile adhesion strength It was.

On the other hand, in order to investigate the flame retardancy, the specimen was placed in a flame retardant tester and flame-fired for 10 seconds, and then immediately scaly and examined whether or not scald was generated. As a result, the known hot melt was generated more than 11 seconds of two residual salts, but the hot melt of the present invention was completely charred without residual salts and showed excellent performance satisfying the UL 94-V ₀ .

The present invention will be described in more detail with reference to the following examples.

However, the following examples are illustrative of the present invention, and the content of the present invention is not limited thereto.

Example 1 Preparation of Hot Melt for Deflection Yoke 1

60 kg of polypropylene wax and 1.5 kg of antioxidant were charged at a speed of 80 rpm at a temperature of about 200 ° C. in a 500 L hot melt stirring tank. The wax and antioxidant were melted while maintaining the temperature inside the tank at 150 to 250 ° C., and 6 kg of styrene butadiene copolymer was added to melt the melt. After stirring for about 2 hours to completely melt the components, 55 kg of a rosin ester copolymer synthetic resin having a molecular weight of 1,000 to 15,000 was further added to melt and mixed well.

Here, 87 kg of talc was added as a filler, and 64 kg of an ethylene propylene copolymer having a molecular weight of about 1,000 to 10,000 was added as a base polymer and melted.

After the base polymer was completely melted, 5 kg of a phthalic acid plasticizer and 18 kg of a phosphate flame retardant were further added, followed by stirring for 45 minutes. In the process, the temperature inside the stirring tank was kept constant at 150 ~ 250 ℃.

After all the compounding raw materials were heated and melted, they were cooled to 25 ° C. using a conveyor belt to prepare chips.

Example 2 Preparation of Hot Melt for Deflection Yoke 2

Hot melt chips were prepared in the same manner as in Example 1 by varying the wax component, base polymer, rubber, and adhesive component resin. The components and contents of each composition are shown in Table 1 below.

Hot Melt Ingredients and Contents ingredient Ingredient Content (% by weight) Example 2 Wax Ingredients Polyethylene 20 Base polymer Ethylene Propylene Copolymer 40 Rubber ingredient SBS 5 Adhesive component resin Rosin ester copolymer 30 Example 3 Wax Ingredients Polypropylene 25 Base polymer Ethylene Propylene Copolymer 45 Rubber ingredient SEBS 5 Adhesive component resin Petroleum resins 20 Example 4 Wax Ingredients Polypropylene 15 Base polymer Ethylene Propylene Copolymer 40 Rubber ingredient SBR 10 Adhesive component resin Rosin phenolic copolymer 35 Comparative example Wax Ingredients Paraffin wax 20 Base polymer Polyamide 35 Rubber ingredient SBR 5 Adhesive component resin Terpene Hydrocarbons 40

Experimental Example 1 Cold Resistance Test

The hot melt prepared in the above example was melted at 180 to 220 ° C. to prepare a specimen coated on the deflection yoke, and then cooled to room temperature. Deflection yoke specimens were fabricated by applying about 5 to 7 g of molten hot melt to the connections between a pair of deflection yoke joints, plastic plates and deflection coils (see FIG. 1 ). The prepared specimens were placed in a thermostat at -20 ° C, -30 ° C, and -40 ° C, respectively. After 168 hours, the specimens were removed and visually observed for cracking and lifting. In the comparative group, a hot melt having polyamide as a main base was used. As a result, the known hot melt has cold resistance only up to -20 ° C, and cracks and lift-up phenomenon have been observed at -30 ° C or lower, but the hot melt of the present invention does not generate cracks or lift-up at all even at -40 ° C. Therefore, the hot melt of the present invention was confirmed to have cold resistance at least up to -40 ℃.

Experimental Example 2 Heat Resistance Test

100 g of hot melt was placed in a glass or iron crucible and left in a dry oven at which the temperature was set at 200 ° C. for 24 hours, and then the occurrence of precipitation and the degree of denaturation (carbonity) were measured. Carbonization was measured by the degree of carbonization (depth) of the tested specimens.

As a result, the hot melt of the present invention hardly precipitated, and the carbonization was also very low, less than 1 mm.

Experimental Example 3 Thermal Shock Strength Test

The hot melt of the present invention was melted at a temperature of 180 to 220 占 폚 to prepare a specimen coated on the deflection yoke, and then cooled to room temperature. Deflection yoke specimens were fabricated by applying about 5 to 7 g of molten hot melt to the connections between a pair of deflection yoke joints, plastic plates and deflection coils (see FIG. 1 ). The thermostat was set to repeat one hour at −40 ° C. and one hour at 110 ° C., and then the specimen was placed and allowed to stand for 50 cycles (100 hours). After that, the specimens were taken out and examined for cracking and lifting.

As a result, the hot melt of the present invention was subjected to a thermal shock of -40 ° C. (1 hour) / 110 ° C. (1 hour) as compared to the hot melt of the comparative example which showed resistance only to a thermal shock of −20 ° C. (1 hour) / 110 ° C. (1 hour). In this case, no cracks and no lift were observed, which resulted in better thermal shock strength.

Experimental Example 4 Tensile Adhesive Strength Measurement Test

The hot melt of the present invention was melted at a temperature of 180 to 220 ° C. and attached to the adhesive surface of the prepared adherend within 5 seconds (see FIG. 2 ), and then left at room temperature for 1 hour. The adherend was fabricated by overlapping two specimens of steel length 100 ± 0.5 mm and width 25 ± 0.5 mm by 12.55 ± 0.5 mm, and applying a hot melt adhesive therebetween. It was then heated in a dry oven at 25 ° C. for 1 hour. After 1 hour, the specimen was taken out and the maximum load was measured until the specimen was destroyed at a tensile speed of 10 mm / min using a push-pull gauge within 10 seconds. The results are shown in Table 2 below.

Tensile Adhesive Strength Test Psalter Tensile Bond Strength (kgf / m ² ) Example 1 75 Example 2 70 Example 3 75 Example 4 75 Comparative example 55

As can be seen from the results of the above table, the hot melt of the present invention exhibits a tensile strength of 15 kgf / m ² or more higher than that of a polyamide-based hot melt having a tensile adhesive strength of about 55 kgf / m ² at about 70 to 75 kgf / m ² . It was.

Experimental Example 5 Flame Retardant Test

Melt the hot melt of the present invention to 180 ~ 220 ℃ and then make a specimen of 125.0 mm wide, 12.7 mm long, 2.5 mm thick, each of the five specimens in a constant temperature and humidity chamber of temperature 23 ± 2 ℃, humidity 50 ± 5% It was left for time. After that, it was left to stand for 168 hours in a dry oven at 70 ± 1 ℃ and pretreated by standing in a desiccator for 4 hours (see UL 94 8.3.2).

The sample is clamped in the flame retardant tester to the upper 6 mm point of the sample, the height of the end of the sample and the bottom surface is adjusted to 300 mm, and the burner angle is adjusted to 45 degrees with a distance of 10 mm from the sample. And, the flame length was set to 20 ± 1 mm. The cotton which spreads on the bottom surface was 50 mm wide, 50 mm long, and 6 mm high. For each sample, a flame was applied for 10 seconds, and then the burner was extinguished. When the residual salts occurred on the sample, the time until the autonomy was measured (t ₁ ) was measured. Again, after adjusting the height of the sample and the burner for the same sample, a flame was added for 10 seconds, the burner was extinguished, and the time from the occurrence of residual flame to the sample until it was burned out was measured (t ₂ ). When the residual salts disappeared in the sample and afterglow occurred, the time until disappearance was measured (t ₃ ). The above procedure was tested in the same manner on the remaining four samples (see UL 94 8.5).

Flame retardancy of the specimens coated with the hot melt of the comparative example and the hot melt composition of the present invention was investigated according to the UL 94 8.1 grading criteria. The grading criteria of UL 94 8.1 are shown in Table 3 below, and the results of the flame retardancy test are shown in Table 4 below.

Flame retardancy rating criteria (UL 94 8.1) Criteria 94-V ₀ 94-V ₁ 94-V ₂ Primary or secondary scrubbing time for individual samples (t ₁ , t ₂ ) ≤10 seconds ≤30 seconds ≤30 seconds Sum of primary or secondary afterflaming time for five samples ≤50 seconds ≤250 seconds ≤250 seconds Sum of afterglow and afterglow time after application of the second flame (t ₂ + t ₃ ) ≤30 seconds ≤60 seconds ≤60 seconds Afterglow or afterglow in the clamp. × × × If the sample falls while burning, the cotton will ignite. × × O

Flame retardancy test results sample result Exam conditions Example 1 UL 94-V ₀ * Sample Preparation: UL 94 8.3.2. Reference (125.0 × 12.7 × 2.5 mm) 5 * Setting: UL 94 8.5 Reference (sample end and burner clearance: 10 mm Flame length: 20 mm) * Test method: UL 94 8.5 (heating for 10 seconds each sample) Example 2 UL 94-V ₀ Example 3 UL 94-V ₀ Example 4 UL 94-V ₀ Comparative example UL 94-V ₁

Although a result embodiment, if the specimen two are not satisfied the UL 94-V ₀ over 11 seconds Remaining flame is generated, respectively, hot melt of the present invention are basil immediately after removing the burner heating was satisfied the UL 94-V ₀ (UL 94 See section 8.1).

The hot melt composition of the present invention not only has excellent adhesion, shock absorption, flame retardancy, etc., but also has excellent cold resistance, heat resistance, and thermal shock strength, which are essential for use in deflection yokes in the field of electric and electronic fields. It is effective as a deflection yoke hot melt that requires high cold resistance, heat resistance and thermal shock strength because it shows the effect of extending the life of CRT, monitor, etc., reliability of operation, prevention of disconnection by overheating, and usability under various extreme climatic conditions. Can be used, which can lead to an improvement in the quality of the CRT.

Claims (12)

Deflection yoke containing 5 to 25% by weight of polyolefin wax component, 25 to 40% by weight of rosin-based adhesive component resin, 10 to 50% by weight of base polymer of ethylene propylene copolymer, and 1 to 10% by weight of styrene-based copolymer rubber Hot melt composition for. The hot melt composition for a deflection yoke according to claim 1, wherein the polyolefin wax is polyethylene or polypropylene wax. The hot melt composition for a deflection yoke according to claim 1, wherein the rosin-based adhesive component resin is a rosin ester hydrocarbon hydrogenated resin or a rosin phenol copolymer synthetic resin. 4. The hot melt composition for a deflection yoke according to claim 3, wherein the rosin phenol copolymer synthetic resin has a weight average molecular weight of 500 to 50,000. The hot melt composition for a deflection yoke according to claim 1, wherein the ethylene propylene copolymer has a weight average molecular weight of 500 to 50,000. The hot-melt composition for deflection yoke of claim 5, wherein the ethylene propylene copolymer has a melt viscosity of 3,000 to 8,000 cps, a softening point of 120 to 160 ° C, and a melt density of 0.7 to 0.8 g / cm 3. The styrene-based copolymer rubber is styrene butadiene random copolymer (SBR), styrene butadiene block copolymer (SBS) or styrene ethylbutadiene copolymer , SEBS) is a styrene copolymer rubber selected from the hot-melt composition for the deflection yoke. The method of claim 1, further comprising at least one of 10 to 40% by weight of filler, 1 to 5% by weight of plasticizer, 0.1 to 2% by weight of antioxidant, 3 to 15% by weight of flame retardant and 0.2 to 3% by weight of color pigment. There is a hot-melt composition for deflection yoke. 9. The hot-melt composition for deflection yoke of claim 8, wherein the filler is calcium carbonate or talc. The hot melt composition for a deflection yoke according to claim 8, wherein the plasticizer is phthalic acid or polybutene. The hot melt composition for a deflection yoke according to claim 8, wherein the flame retardant is halogen or phosphate. 10 to 20% by weight of the polyethylene wax, 30 to 35% by weight of the adhesive component resin of the rosin ester copolymer, 10 to 30% by weight of the base polymer of the ethylene propylene copolymer, styrene butadiene block copolymer rubber 2 to 8 Hot-melt composition for deflection yoke comprising a weight%.