JPH0881658A - Repeelable antistatic protective adhesive film - Google Patents

Abstract

PURPOSE: To obtain a repeelable protective adhesive film excellent in transparency, not generating static electricity on adhering and peeling works, free from the breakage of IC circuits, etc., and not staining the surface of the panel, etc., by incorporating a water-soluble resin into an adhesive layer. CONSTITUTION: This film is produced by forming a repeelable adhesive layer on the surface of a synthetic resin film base material and mixing (B) a water-soluble resin into (A) the adhesive layer. The component B is preferably mixed in an amount of 1-100 pts.wt. per 100 pts.wt. of the component A, and has preferably repeating units of formula: -[YXYR2 ]- Y is repeating units of (i) -[CH2 CH2 O]- and (ii) -[CH2 CH(R1 )O]-, wherein the unit (i) is >=70wt.%, and the repeating number of the unit (i) is a positive number, and the repeating number of the unit (ii) is 0 or a positive number; R1 is hydrocarbon; X is the residue of an organic compound having two active hydrogen groups; R2 is the residue of a dicarboxylic acid compound, the residue of a diisocyanate compound}. The component A is preferably an acrylic resin, an ethylene-vinyl acetate copolymer, an ethylene-acrylate ester copolymer, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a liquid crystal panel and a CRT.
The present invention relates to an antistatic protective film composed of a removable protective pressure-sensitive adhesive sheet or tape having an antistatic function, which is used to protect the surface of a (cathode ray tube) or the like during production, transportation, or storage. .

[0002]

2. Description of the Related Art A removable protective pressure sensitive adhesive sheet made of synthetic resin for preventing scratches, adhesion of dust, pollution, etc. during manufacture and transportation of liquid crystal panels and CRTs for personal computers, word processors, calculators, etc. Alternatively, a protective adhesive tape is attached to a liquid crystal panel or a CRT surface for protection. However, when the conventional protective sheet or protective tape finishes its role of protecting the liquid crystal panel surface or the like and then peels off from the panel surface or the like, static electricity is generated, and as a result, the IC of the circuit is destroyed or dust or dust is generated on the panel surface. Since problems such as adhesion may occur, the following measures have been taken to avoid such problems.

A protective sheet or tape prepared by kneading a surface active agent into a base material or an adhesive is used. A protective sheet or tape in which a conductive filler such as carbon black is kneaded is used. A protective sheet or tape in which a conductive or hydrophilic resin is kneaded is used. Use a static eliminator.

However, among the above trouble avoiding means,
The kneaded mixture of the above surfactants has an insufficient antistatic effect, is greatly affected by humidity and is unstable, and changes in the adhesive properties when the surfactant bleeds out into the adhesive. And glue residue is more likely to occur,
Although surfactants that have a high possibility of contaminating the adherend even if there is no adhesive residue gradually evaporate into the air and lose their antistatic effect, there are still many problems to be solved. I have a problem.

Further, the one in which the conductive filler is kneaded has poor transparency, and there is a problem that it is difficult to check the adherend surface with the protective sheet attached, and the conductivity,
Many of the materials that are mixed with hydrophilic resin do not have good compatibility with the base material and the resin that serves as an adhesive, and do not disperse cleanly, so the antistatic effect is not high, and when using a static eliminator, etc. Since the static electricity removal capacity is limited, it is not possible to speed up the work of attaching the protective sheet, and a static eliminator is required to remove the protective sheet, which limits the work place (environment) ( There is a problem that static electricity is generated if it is peeled off without the equipment.

[0006]

Therefore, the present invention can solve the problems associated with the conventional antistatic protective film as described above, is excellent in transparency, and is free from static electricity during sticking and peeling work. Therefore, there is no destruction of the IC of the circuit due to the charging of the panel surface,
It is another object of the present invention to provide a removable antistatic protective film that does not cause contamination of the panel surface or the like due to dust adhesion due to adhesive residue or the like.

[0007]

DISCLOSURE OF THE INVENTION The present invention for solving the above-mentioned problems has a pressure-sensitive adhesive layer coated on a synthetic resin sheet-like or tape-like film substrate surface, and said adhesive layer The present invention relates to a removable antistatic protective pressure-sensitive adhesive film containing a water-soluble and highly transparent resin.

In particular, the present invention is a removable antistatic protective pressure-sensitive adhesive film characterized in that it is one or more selected from compounds consisting of repeating units represented by the following general formula (1). It is about. - [YXYR _2] - ----- (1) wherein, Y is - [CH ₂ CH ₂ O] - and - [CH ₂ C
A unit composed of repeating H (R ₁ ) O]-. However, in Y - [CH ₂ CH ₂ O] - it is present more than 70 wt%, - [CH ₂ CH ₂ O] - repeat number of a positive number. Furthermore, - [CH ₂ CH (R ₁₎ O] -
The number of repetitions of is 0 or a positive number. R ₁ is a hydrocarbon group. X is an organic compound residue having two active hydrogen groups. R ₂ is a dicarboxylic acid compound residue or a diisocyanate compound residue. ]

Further, the present invention is one or more selected from compounds having a weight average molecular weight of 50,000 or more obtained by reacting the following components (A) and (B) as the water-soluble resin of the general formula (1). The present invention relates to a removable antistatic protective pressure-sensitive adhesive film. (A): A polyoxyalkylene polyol having a weight average molecular weight of 1,000 or more obtained by addition-polymerizing an alkylene oxide containing 70% by weight or more of ethylene oxide to a compound having two active hydrogen groups. (B): At least one of dicarboxylic acid compounds and diisocyanate compounds.

Further, the present invention comprises a synthetic resin film substrate having excellent transparency and a releasable pressure-sensitive adhesive layer coated on the film substrate surface, and the pressure-sensitive adhesive layer is transparent as a protective pressure-sensitive adhesive film. The water-soluble resin that does not impair the property is 1 to 100 parts by weight, preferably 5 to 50 parts by weight, more preferably 10 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive layer.
The present invention relates to a removable antistatic protective pressure-sensitive adhesive film which is added and contained at a ratio of -30 parts by weight.

Further, in the present invention, the adhesive is selected from acrylic type, ethylene-vinyl acetate copolymer type, ethylene-acrylic acid ester type, styrene-isoprene block copolymer type, and styrene-butadiene block copolymer type. The present invention relates to a removable antistatic protective pressure-sensitive adhesive film, which is one or more kinds.

The film substrate used for the sheet-like or tape-like adhesive film of the present invention includes polyethylene, polypropylene, polyester, polyvinyl chloride, polyamide, ethylene / propylene copolymer, polystyrene, polycarbonate, polyurethane, polyacetal and the like. Is a synthetic resin film, particularly a film made of a thermoplastic resin that can be formed into a film by a melt extrusion method. The synthetic resin substrate preferably has a thickness of 10 μm to 100 μm. If it is less than 10 μm, the function of protecting the panel surface or the like is not sufficient, and if it exceeds 100 μm, it is not preferable because it lacks flexibility and the shape following property deteriorates.

The pressure-sensitive adhesive used in the pressure-sensitive adhesive sheet or tape of the present invention has a characteristic that it can be removably attached without leaving an adhesive residue on the surface of a liquid crystal panel, etc. There is no particular limitation as long as it does not damage, for example, acrylic type, EVA (ethylene-vinyl acetate copolymer) type, EEA (ethylene-acrylic acid ester copolymer) type, SIS (styrene-isoprene block). Copolymers such as hot melt type and SBS (styrene-butadiene block copolymer) type, which can be formed into a film by a melt extrusion method, are preferable. The pressure-sensitive adhesive is preferably applied to the surface of the base material as a layer having a thickness of 3 to 50 μm to form a removable pressure-sensitive adhesive layer.

The water-soluble resin added to the pressure-sensitive adhesive film base material and / or the pressure-sensitive adhesive layer of the present invention is compatible with the materials of the base material and the pressure-sensitive adhesive layer and adversely affects the pressure-sensitive adhesiveness and removability of the pressure-sensitive adhesive layer. Are preferred, and those which do not impair their transparency are preferred, and a water-soluble polymer compound having a weight average molecular weight of 50,000 or more composed of repeating units represented by the following general formula (1) is particularly preferred. .

-[YXYR ₂ ]-(1) [wherein Y represents-[CH ₂ CH ₂ O]-and-[CH ₂ C]
A unit composed of repeating H (R ₁ ) O]-. However, in the Y - [CH ₂ CH ₂ O] - it is present more than 70 wt%, - [CH ₂ CH ₂ O] - repeat number of a positive number. Also, - [CH ₂ CH (R ₁₎ O] - is the number of repetitions of a 0 or a positive number. R ₁ is a hydrocarbon group. X is an organic compound residue having two active hydrogen groups. R ₂ is a residue of a dicarboxylic acid compound or a residue of a diisocyanate compound. ]

The water-soluble polymer compound composed of the repeating unit represented by the general formula (1) has a weight average molecular weight of 500 obtained by reacting the following components A and B:
It is a polymer compound of 00 or more. (A): A polyoxyalkylene polyol having a weight average molecular weight of 1,000 or more obtained by addition-polymerizing an alkylene oxide containing 70% by weight or more of ethylene oxide to a compound having two active hydrogen groups. (B): At least one of dicarboxylic acid compounds and diisocyanate compounds.

Examples of the compound having two active hydrogen groups in the component A used in the above reaction include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,
Alicyclic diols such as 6-hexanediol, neopentyl glycol, bisphenol A, polytetramethylene glycol, and cyclohexane-1,4-dimethanol,
Examples include amines such as butylamine, octylamine, laurylamine, cyclohexylamine and aniline.

The alkylene oxide containing 70% by weight or more of ethylene oxide which can be used for producing the component A used in the above reaction includes ethylene oxide alone, propylene oxide containing 70% by weight or more of ethylene oxide, butylene oxide, styrene oxide and the like. Mention may be made of alkylene oxide mixtures. If the ethylene oxide content is less than 70% by weight based on the total weight of the alkylene oxide, it tends to be insoluble in water.

In the reaction for producing the polyoxyalkylene polyol which is the component A, a compound having two active hydrogen groups is added with an alkylene oxide containing 70% by weight or more of ethylene oxide, such as sodium hydroxide or potassium hydroxide. About 90 to 20 with caustic as a catalyst
It can be obtained by block or random addition polymerization at a temperature of 0 ° C. for about 2 to 30 hours. The resulting polyoxyalkylene polyol has a weight average molecular weight of 10
00 or more, preferably 5000 to 30000. When the weight average molecular weight is less than 1000, the proportion of the corresponding dicarboxylic acid compound and the coupling agent of the diisocyanate compound added is increased, and the water solubility tends to deteriorate, which is not preferable.

Among the component B used in the above reaction, examples of the dicarboxylic acid compound include those described in the following (a), (b) and (c). (A) phthalic acid, isophthalic acid, terephthalic acid, malonic acid, succinic acid, sebacic acid, maleic acid, fumaric acid, adipic acid,
Itaconic acid, (b) lower alkyl ester such as methyl ester, dimethyl ester, ethyl ester, diethyl ester, propyl ester, dipropyl ester, butyl ester, dibutyl ester of (a), (c)
An acid anhydride of (a),

In the component B used in the above reaction, examples of the diisocyanate compound include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate and 4,4'-methylenebis-.
(Cyclohexyl isocyanate) and the like.

Among the reactions for producing the water-soluble polymer compound composed of the repeating unit represented by the general formula (1), in the case of the reaction using the dicarboxylic acid compound as the component B, the polyoxyalkylene polyol (A ) Is prepared and the dicarboxylic acid compound (B) is added thereto,
It is heated to 80 to 250 ° C. and heated to 0.1 to
Dehydration or dealcoholization is performed under reduced pressure of 2.7 × 10 ³ Pa. The reaction time during this period is usually 30 minutes to 10 hours. When the component (A) and the component (B) are reacted with each other, the mixing ratio (A / B) of both is specifically an equivalence ratio, A / B = 1 / 0.5 to 1 / 3.5, A / B = 1 / 0.95 to 1 / 3.5 is preferable.

Further, in the reaction using a diisocyanate compound as the B component, that is, the urethanization reaction with the diisocyanate compound, for example, the compounding ratio of the polyoxyalkylene polyol (A) and the diisocyanate compound (B) is set to an NCO / OH equivalent ratio of 0. It is carried out by mixing within a range of 0.5 to 1.5 and reacting at a temperature of 80 to 150 ° C. for 1 to 5 hours. The weight average molecular weight of the water-soluble polymer compound thus obtained is preferably set to 50,000 or more, more preferably 10,000.
It is 0-300000.

These water-soluble resins are usually preferably added in an amount of 1 to 100 parts by weight per 100 parts by weight of the pressure-sensitive adhesive layer. If the addition ratio is less than 1 part by weight per 100 parts by weight of the pressure-sensitive adhesive layer, the antistatic function may be insufficient, and if it exceeds 100 parts by weight, the cost increase may be commensurate with no further effect expected. .

[0025]

According to the present invention described above, both the film substrate and the pressure-sensitive adhesive layer are electrically charged by the conductive action which is considered to be derived from the water retention of the water-soluble resin added to the pressure-sensitive adhesive layer. Therefore, the surface of the liquid crystal panel or the like in contact with the pressure-sensitive adhesive layer is not charged when the pressure-sensitive adhesive layer is peeled off. In addition, the water-soluble resin is compatible with the film base material and the pressure-sensitive adhesive layer even if they are present, and does not impair the transparency, and the addition ratio is 100 parts by weight or less per 100 parts by weight of the pressure-sensitive adhesive. If so, it does not hinder the adhesiveness of the adhesive layer. Furthermore, since a resin that can be hot melt extruded is used as the film base material and the adhesive resin, the base film and the adhesive layer can be laminated in a state where they are firmly bonded together by a co-extrusion method. Moreover, the adhesive residue of the adhesive can be reduced.

[0026]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Example 1 Polyethylene glycol obtained by addition-polymerizing ethylene oxide alone to ethylene glycol (ethylene oxide 1
To 100 parts of 00% and weight average molecular weight of 10,000), 2.4 parts of dimethyl sebacic acid was added, and transesterification reaction was performed by a known method to obtain a water-soluble resin (a) having a weight average molecular weight of 150,000. In the repeating unit represented by the general formula (1), Y, X and R ₂ are as follows.

Embedded image

LDPE (manufactured by Mitsubishi Kasei Co .: trade name F-14)
1) 100 parts by weight of the above water-soluble resin (a) 2
A mixture containing 0 parts by weight was used as a composition for a base film, and EVA (product name: V-501H manufactured by Mitsubishi Petrochemical Co., Ltd.) 10
A mixture of 20 parts by weight of the above water-soluble resin A with respect to 0 parts by weight was used as a pressure-sensitive adhesive composition, and the thickness of the base film was 45 μ and the thickness of the pressure-sensitive adhesive layer was measured by a two-layer extrusion method using a T-die. A removable antistatic pressure-sensitive adhesive film was produced so as to have a thickness of 15 μm. The properties shown in Table 1 were evaluated for the removable antistatic pressure-sensitive adhesive film.

Example 2 Addition of 2.7 parts of dimethyl isophthalate to 100 parts of polyalkylene glycol (ethylene oxide 85%, weight average molecular weight 14000) obtained by addition-polymerizing propylene oxide and ethylene oxide in a block to aniline was added to ester. Weight average molecular weight of 1700 due to exchange reaction
A water-soluble resin (b) of 00 was obtained. The Y, X and R ₂ are as follows.

Embedded image A removable antistatic pressure-sensitive adhesive film was produced in the same manner as in Example 1 except that the above water-soluble resin (b) was used instead of the water-soluble resin (a) in Example 1. This property was as shown in Table 1.

Example 3 Polyethylene glycol obtained by addition-polymerizing ethylene oxide alone to ethylene glycol (ethylene oxide 1
A water-soluble resin (c) having a weight average molecular weight of 130000 was obtained by adding 1.9 parts of dimethyl terephthalate to 100 parts of 100% of a weight average molecular weight of 20000).
I got The Y, X and R ₂ are as follows.

[Chemical 3] A removable antistatic pressure-sensitive adhesive film was produced in the same manner as in Example 1 except that the above water-soluble resin (c) was used instead of the water-soluble resin (a) in Example 1. This property was as shown in Table 1.

Example 4 Polyethylene glycol obtained by addition-polymerizing ethylene oxide alone to ethylene glycol (ethylene oxide 1
00%, weight average molecular weight 10000) 100 parts, hexamethylene diisocyanate 1.6 parts were added and urethanization reaction was carried out by a known method to obtain a weight average molecular weight 13,000.
A water-soluble resin (d) of 0 was obtained. This is because in the repeating unit represented by the general formula (1), Y, X, R ₂
Is as follows.

[Chemical 4] A removable antistatic pressure-sensitive adhesive film was produced in the same manner as in Example 1 except that the above water-soluble resin (d) was used instead of the water-soluble resin (a) of Example 1. This property was as shown in Table 1.

Example 5 Polyalkylene glycol (ethylene oxide 85%, weight average molecular weight 10) obtained by addition-polymerizing ethylene glycol with propylene oxide and ethylene oxide in blocks.
000) to 100 parts of 2,4-tolylene diisocyanate was added 3.1 parts to carry out a urethanization reaction by a known method to prepare a water-soluble resin (e) having a weight average molecular weight of 100,000. The Y, X and R ₂ are as follows.

[Chemical 5] A removable antistatic pressure-sensitive adhesive film was produced in the same manner as in Example 1 except that the above water-soluble resin (e) was used instead of the water-soluble resin (a) in Example 1. This property was as shown in Table 1.

Example 6 A water-soluble resin (a) of Example 1 was added to 100 parts by weight of a solid content of an acrylic re-peelable pressure-sensitive adhesive (SK Dyne 1473H, manufactured by Soken Chemical Industry Co., Ltd.) using a polyester film as a base material.
Using 20 parts by weight as a pressure-sensitive adhesive composition, a removable antistatic pressure-sensitive adhesive film was produced so that the thickness of the pressure-sensitive adhesive layer was 15 μm. This property was as shown in Table 1.

Comparative Example 1 A removable pressure-sensitive adhesive film was prepared in the same manner as in Example 1 except that the water-soluble resin (a) was not used. This property was as shown in Table 1. Comparative Example 2 A releasable pressure-sensitive adhesive film was prepared in the same manner as in Example 6 except that the water-soluble resin (a) was not used. This property was as shown in Table 1.

[0034]

[Table 1]

[0035]

As described above in detail, the removable protective pressure-sensitive adhesive sheet or tape of the present invention protects the display surface of an electronic device such as a liquid crystal panel while maintaining the transparency of the base material and the like. With excellent function, even when peeled after finishing the role as a protective sheet or tape because the protective adhesive sheet or tape itself is not charged,
Without charging the display surface of electronic devices,
Therefore, destruction of electronic parts such as ICs due to the charging of the surface portion will not occur.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location C09J 7/02 JKK JLF JLH (72) Inventor Takeshi Fujita 114-9 Koneo, Hirono-cho, Uji-shi, Kyoto Prefecture (72) Inventor Tadamitsu Isoda 64-9 Shinmeimiyakita, Uji City, Kyoto Prefecture

Claims (5)

[Claims] 1. A removable, antistatic protective pressure-sensitive adhesive film having a removable pressure-sensitive adhesive layer on the surface of a synthetic resin film substrate, wherein the pressure-sensitive adhesive layer contains a water-soluble resin. 2. The removable antistatic protective adhesive according to claim 1, wherein the water-soluble resin is added in an amount of 1 to 100 parts by weight per 100 parts by weight of the adhesive layer. the film. 3. The resin according to claim 1, wherein the water-soluble resin is one kind or two or more kinds selected from compounds consisting of repeating units represented by the following general formula (1). A peelable antistatic protective adhesive film. - [YXYR _2] - ----- (1) wherein, Y is - [CH ₂ CH ₂ O] - and - [CH ₂ C
A unit composed of repeating H (R ₁ ) O]-. However, in Y - [CH ₂ CH ₂ O] - it is present more than 70 wt%, - [CH ₂ CH ₂ O] - repeat number of a positive number. Furthermore, - [CH ₂ CH (R ₁₎ O] -
The number of repetitions of is 0 or a positive number. R ₁ is a hydrocarbon group. X is an organic compound residue having two active hydrogen groups. R ₂ is a dicarboxylic acid compound residue or a diisocyanate compound residue. ] 4. The water-soluble resin is one or more selected from compounds having a weight average molecular weight of 50,000 or more obtained by reacting the following compounds (A) and (B). Item 1. The removable antistatic protective pressure-sensitive adhesive film according to Item 1, 2 or 3. (A): A polyoxyalkylene polyol having a weight average molecular weight of 1,000 or more obtained by addition-polymerizing an alkylene oxide containing 70% by weight or more of ethylene oxide to a compound having two active hydrogen groups. (B): At least one of dicarboxylic acid compounds and diisocyanate compounds. 5. The adhesive is an acrylic type, an ethylene-vinyl acetate copolymer type, an ethylene-acrylic acid ester type,
5. Removable charging according to any one of claims 1 to 4, which is one or more selected from a styrene-isoprene block copolymer system and a styrene-butadiene block copolymer system. Preventive protective adhesive film.