JP2019084520A - Manufacturing method for laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a laminated body having excellent adhesiveness. SOLUTION: A step 1 of dry-treating a surface A of a plastic to obtain a dry-treated plastic having a dry-treated surface B, and at least one of the surface B selected from the group consisting of water and a polar solvent. Step 2 to obtain a cleaning plastic having a surface C wiped with the cleaning tool by wiping with a cleaning tool containing the mixture, and applying at least one selected from the group consisting of an adhesive and a primer to the surface C to obtain a laminated body. A method for producing a laminated body, comprising the step 3 of obtaining the above. [Selection diagram] None

Description

  The present invention relates to a method of manufacturing a laminate.

Conventionally, in order to improve the adhesion between a plastic and an adhesive, it is known that the plastic is surface-treated by dry treatment such as plasma treatment to hydrophilize the surface of the plastic (for example, Non-Patent Document 1).
Moreover, in the plastic after dry processing, it is generally considered that the surface after dry processing is not cleaned or not in contact with the surface in order to prevent the decrease in adhesion.

"Technology of adhesion", vol. 36 No. 3 (2016) Volume 124 [24]-[28] Published at the end of December 2016, the Japan Institute of Adhesiveness

Under these circumstances, when the present inventors evaluated the laminate of the plasma-treated polyolefin and the adhesive with reference to Non-Patent Document 1, it may be that such a laminate may have low adhesion. It became clear.
Then, an object of this invention is to provide the manufacturing method of the laminated body which is excellent in adhesiveness.

As a result of intensive studies to solve the above problems, the present inventors have found that it is desirable to wipe the surface of a dry-treated plastic with a cleaning tool containing at least one selected from the group consisting of water and polar solvents. It has been found that an effect can be obtained, and the present invention has been made.
The present invention is based on the above-mentioned findings etc., and specifically solves the above-mentioned subject by the following composition.

1. Dry-treating the plastic surface A to obtain a dry-treated plastic having the dry-treated surface B;
Wiping the surface B with a cleaning tool containing at least one selected from the group consisting of water and a polar solvent to obtain a cleaning plastic having the surface C wiped with the cleaning tool;
A method for producing a laminate, comprising: applying at least one selected from the group consisting of an adhesive and a primer to the surface C, and obtaining a laminate.
2. The plastic is selected from the group consisting of polyolefin, polyethylene terephthalate, polymethyl methacrylate resin, polycarbonate resin, polystyrene resin, acrylonitrile styrene copolymer resin, polyvinyl chloride resin, acetate resin, acrylonitrile butadiene styrene resin, polyester resin and polyamide resin The manufacturing method of the laminated body of said 1 which is at least 1 sort (s).
3. The method for producing a laminate according to the above 1 or 2, wherein the dry treatment is at least one selected from the group consisting of plasma treatment, corona treatment, flame treatment, itro treatment, ultraviolet (UV) treatment and excimer treatment.
4. In the process 2, a force of 25 to 0.25 kPa is applied to the surface B, and the surface B is wiped with the cleaning tool, wherein the method for manufacturing a laminate according to any one of 1 to 3 above.
5. The method for producing a laminate according to any one of the above 1 to 4, wherein the cleaning tool contains water.
6. 5. Manufacturing method of laminated body in any one of said 1-5 which provides adhesive agent to said surface C.
7. 7. Manufacturing method of laminated body in any one of said 1-6 whose wetting tension of said surface B is 39 mN / m or more.
8. The manufacturing method of the laminated body in any one of said 1-7 whose wetting tension of the said surface C is 34-65 mN / m.
9. 9. The method for producing a laminate according to any one of 1 to 8, wherein the lowering width from the wetting tension of the surface B to the wetting tension of the surface C is 5 to 20 mN / m.
10. The manufacturing method of the laminated body in any one of said 1-9 whose wetting tension of the said surface B exceeds 65 mN / m.
11. 11. The method for producing a laminate according to the above 10, wherein the wetting tension of the surface C is more than 45 mN / m and not more than 65 mN / m.

  According to the method for producing a laminate of the present invention, a laminate having excellent adhesiveness can be produced.

FIG. 1 is a graph showing the results of XPS analysis of the surface of each plastic used in Example 1.

The present invention will be described in detail below.
In addition, in this specification, the numerical range represented using "-" means the range which includes the numerical value described before and after "-" as a lower limit and an upper limit.
In the present specification, each component used can be used alone or in combination of two or more substances corresponding to the component. When the component contains two or more substances, the content of the component means the total content of the two or more substances.
Also, in the present specification, each component to be used is not particularly limited as to its production method. For example, conventionally known ones can be mentioned.

[Method of manufacturing laminate]
The method for producing a laminate of the present invention (the production method of the present invention) is
Dry-treating the plastic surface A to obtain a dry-treated plastic having the dry-treated surface B;
Wiping the surface B with a cleaning tool containing at least one selected from the group consisting of water and a polar solvent to obtain a cleaning plastic having the surface C wiped with the cleaning tool;
It is a manufacturing method of a layered product which has at least one sort chosen from a group which consists of an adhesives and a primer on the above-mentioned surface C, and has process 3 of obtaining a layered product.

Since the composition of the present invention has such a constitution, it is considered that a desired effect can be obtained. Although the reason is not clear, it is presumed that it is as follows.
Generally, when a plastic is subjected to a dry treatment such as plasma treatment, a hydrophilic group having, for example, an oxygen atom or the like is generated on the surface of the plastic. Moreover, with the generation of the above-mentioned hydrophilic group, the chain of the polymer constituting the plastic may be cut.
When the above-mentioned dry processing is excessively applied to the plastic to generate a large amount of hydrophilicity, the polymer on the surface of the plastic is also cut more, as a result, the polymer on the outermost surface of the plastic is cut short and the polymer having a short molecular chain (Short polymer) is generated. When many of the short polymers are generated, it is considered that the short polymer layer (short polymer layer) covers at least a part of the outermost surface of the plastic. The short polymer layer is considered as an extremely thin layer.
Thus, when the plastic is subjected to a dry treatment (excess), the plastic is made of the polymer which is hydrophilized and has long molecular chains under the short polymer layer on the outermost surface and the short polymer layer. It is considered to have a layer (appropriate processing unit).

Here, since the short polymer has a hydrophilic group by dry treatment (the short polymer may have a relatively large number of hydrophilic groups), if an adhesive or the like is applied to the dry-treated plastic, It is considered that plastic and adhesive etc. are easy to bond.
However, it has become clear that the adhesion between the dry-treated plastic and the adhesive may be low (see Comparative Example 1 in the present specification).

This is because when the adhesive or the like is applied to the plastic having the short polymer on the surface to form a laminate, in the laminate, the adhesive or the like can react with the short polymer, but it is under the short polymer layer. It is considered that it is difficult to react with the layer of the polymer which is hydrophilized and whose molecular chain is long (the layer which can be essentially a substrate).
Thus, the adhesive and the like are less likely to react with the layer of the polymer which is hydrophilized and the molecular chain remains long, and the short polymer has less entanglement of the polymer as compared with the polymer before cutting. The present inventors speculate that the above-mentioned hydrophilized and molecular chains are likely to be exfoliated from the boundary between the polymer layer and the short polymer layer which remain long.

On the other hand, in the production method of the present invention, in step 2, the short polymer is removed by wiping the surface B of the dry-treated plastic with a cleaning tool containing at least one selected from the group consisting of water and polar solvents. It can be considered that it can be removed from the surface B.
This is because the short polymer is dissolved in at least one selected from the group consisting of water and a polar solvent, and the physical force is applied to the surface B by wiping the surface B with the cleaning tool, and the short polymer is the surface B It is thought to be wiped out from the
And, on the surface C of the cleaning plastic after being wiped with the cleaning tool, it is considered that a polymer which is hydrophilized and has a long molecular chain exists.
As described above, there is a polymer that is hydrophilized on the surface C and the molecular chain remains long, and the adhesive or the like can directly react with the surface C, whereby the laminate produced by the production method of the present invention is excellent in adhesiveness. Conceivable.
Hereinafter, each component contained in the composition of this invention is explained in full detail.

<< Step 1 >>
Step 1 is a step of dry-treating the plastic surface A to obtain a dry-treated plastic having the dry-treated surface B.

<Plastic>
The plastic used in step 1 is not particularly limited.
Examples of the plastic include polyolefin, polyethylene terephthalate, polymethyl methacrylate resin, polycarbonate resin, polystyrene resin, acrylonitrile styrene copolymer resin, polyvinyl chloride resin, acetate resin, acrylonitrile butadiene styrene resin, polyester resin and polyamide resin.
Among them, polyolefin is preferable. The polyolefin is not particularly limited. For example, polyethylene; polypropylene; ethylene-propylene copolymer; cycloolefin polymer (COP) such as a polymer obtained by ring-opening polymerization of norbornene and hydrogenation, co-coexistence of tetracyclododecene and olefin such as ethylene Examples include cycloolefin copolymers (COC) such as polymers.
The plastic may be, for example, a poorly adhesive resin.

  The above-mentioned plastic can further contain an additive. The additive is not particularly limited as long as it can be added to the resin. For example, fillers such as glass fibers, carbon fibers and white fillers (eg talc) can be mentioned.

<Dry treatment>
The dry treatment to be applied to the surface A of the plastic in step 1 is not particularly limited. Examples include plasma treatment, corona treatment, flame treatment, intro treatment, ultraviolet (UV) treatment and excimer treatment.
Among them, plasma treatment is mentioned as one of the preferable embodiments. Plasma treatment is not particularly limited.
As source gas used for dry processing, oxygen, nitrogen, and air are mentioned, for example. The source gas may be dried.

The dry processing can impart hydrophilic groups to the plastic. Examples of the hydrophilic group include an oxygen atom-containing group such as a hydroxy group, an aldehyde group, a carboxy group, a carbonyl group and an ether bond; and a nitrogen atom-containing group such as an amino group and an imino group.
One or both sides of the above plastic may be dry processed.

<Dry-processed plastic>
In step 1, after dry processing, dry processed plastic is obtained. The dry processed plastic has a dry processed surface B.
-Wetting tension of surface B The wetting tension of surface B is usually 34 mN / m or more, and can be 39 mN / m or more. The upper limit of the wetting tension of the surface B is not particularly limited, but may be 73 mN / m or less.

However, depending on the degree of the above-mentioned dry processing etc., the above-mentioned surface B may become an over-treatment area beyond the aptitude processing. It is believed that the greater the wetting tension, the greater the damage to the plastic surface due to dry processing (e.g., the generation of the above-mentioned short polymers).
In the present invention, when the wetting tension of the surface B exceeds 65 mN / m, it is assumed that the surface B is in a state of overtreatment (corresponding to an overtreatment region).

In the present invention, the wetting tension of (the surface A, B or C) of the substrate was measured under room temperature conditions according to JIS K 6768: 1999 “Plastic-film and sheet-wetting tension test method”. A wet tension test mixture (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a test mixture.
The upper limit of the wetting tension which can be measured by the above-mentioned measuring method is 73.0 mN / m.
Therefore, in the present invention, when the measured value of the wetting tension is 73 mN / m, it means that the wetting tension is 73 mN / m or more.

<< Step 2 >>
Step 2 is a step of wiping the surface B with a cleaning tool containing at least one selected from the group consisting of water and a polar solvent to obtain a cleaned plastic having the surface C wiped with the cleaning tool.

<Cleaning tool>
In step 2, in order to wipe the surface B of the dry-treated plastic, a cleaning tool comprising at least one selected from the group consisting of water and polar solvents is used.
In the present invention, the "cleaning tool containing at least one selected from the group consisting of water and polar solvent" may be simply referred to as "cleaning tool" hereinafter. "The at least 1 sort (s) chosen from the group which consists of water and a polar solvent" may only be hereafter called "water etc." Moreover, the base used to contain the said water etc. is called "a washing | cleaning base material."
It is preferable that the said washing | cleaning tool contains water from a viewpoint of being more excellent in adhesiveness, and it is more preferable to contain only water.
Further, in the present invention, the cleaning tool may be a cleaning tool containing only at least one selected from the group consisting of water and a polar solvent.

  10-95 mass% is preferable with respect to the said whole washing | cleaning tool, and, as for content of at least 1 sort (s) chosen from the group which consists of water and a polar solvent in the said washing | cleaning tool, 80-95 mass% is more preferable.

(Washing base material)
The cleaning substrate used to contain at least one selected from the group consisting of water and polar solvents is not particularly limited.
Examples of the cleaning base include cloth, paper, and sponge.
Examples of the material of the cleaning base include cellulose, polyamide, polyester, and melamine.
Examples of the form of the cloth include non-woven fabric and woven fabric.
It is mentioned as a preferable aspect to remove a roller and a brush from a washing | cleaning base material.

(water)
There is no particular limitation on the water that can be contained in the cleaning tool. For example, distilled water can be mentioned.

(Polar solvent)
The polar solvent which the said washing | cleaning tool can contain is not restrict | limited in particular. For example, alcohols such as methanol, ethanol, propanol and isopropanol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate and butyl acetate; ether compounds such as tetrahydrofuran and diethyl ether; dimethyl sulfoxide; .
Among these, from the viewpoint of better adhesion, alcohols and ketones are preferable, and methanol and acetone are more preferable.

  When water and a polar solvent are used in combination, the mass ratio of the polar solvent to water (polar solvent / water) is preferably 0.1 to 99% by mass, and 0.1 to 50% by mass from the viewpoint of excellent adhesion. Is more preferred.

(Preparation method of cleaning tool)
As a method of preparing the cleaning tool, for example, the cleaning base is immersed in the water or the like, the cleaning tool containing the water or the like is pulled up from the water or the like, and the cleaning tool pulled up is squeezed. The device can be prepared.
The cleaning tool may be in a state in which the cleaning composition is impregnated in the cleaning base.

<Wipe>
When wiping the surface B with the cleaning tool, the cleaning tool can be used, for example, in the spread state or in the folded state, or in a state in which one or more cleaning tools are stacked.
Also, the cleaning tool may be reciprocated on the surface B, for example, but it is preferable to wipe it once.
In step 2, it is preferable to wipe the surface B with the cleaning tool by applying a force (pressure) of 25 to 0.25 kPa to the surface B (for example, in the vertical direction). The force is more preferably 13.5 to 1.0 kPa.
(How to measure force)
The above force is carried by placing the dry processed plastic on an electronic balance (trade name BX 4200H, manufactured by Shimadzu Corporation), adjusting the zero point, wiping the surface of the dry processed plastic with a cleaning tool, and applying the dry processed plastic. Load was measured. Note that 1 kgf is 9.8 N.
The force was calculated by dividing the load when wiped once or the average value of the above measurements when wiped or reciprocated a plurality of times by the area of the cleaning tool in contact with the dry-treated plastic.

(Washing plastic)
In step 2, a cleaning plastic having a surface C wiped with the cleaning tool can be obtained.
After being wiped with the cleaning tool, water or the like remaining on the surface C may be dried. The drying method is not particularly limited. For example, natural drying can be mentioned.

(Wet tension of surface C)
The wetting tension of the surface C is preferably 34 to 65 mN / m.
The wetting tension of the surface C is preferably smaller than the wetting tension of the surface B.

· When the wetting tension of surface B exceeds 65 mN / m, the wetting tension of surface C preferably exceeds 65 mN / m when the wetting tension of surface B exceeds 65 mN / m, More than 45 mN / m and 65 mN / m or less is more preferable, 50 to 65 mN / m is more preferable, and 60 to 65 mN / m is particularly preferable.

-When the wetting tension of surface B is 65 mN / m or less, when the wetting tension of surface B is 65 mN / m or less, the wetting tension of surface C is 34 mN / m or more and less than 65 mN / m It is preferable that the pressure be as high as 34 mN / m to 60 mN / m.

The lowering width from the wetting tension of the surface B to the wetting tension of the surface C The lowering width from the wetting tension of the surface B to the wetting tension of the surface C is preferably in the range of 5 to 20 mN / m. The same applies to the case where the wetting tension of the surface B exceeds 65 mN / m.
The decrease width from the wetting tension of surface B to the wetting tension of surface C means the difference from the wetting tension of surface B to the wetting tension of surface C (wetting tension of surface B-wetting tension of surface C).
In the present invention, when the measurement result of the wetting tension of B is 73 mN / m, this means that it is 73 mN / m or more as described above. However, in the case of calculation of the said fall width, the wetting tension of the said surface B was uniformly 73 mN / m. The same applies to the surface C.

<< Step 3 >>
Step 3 is a step of applying at least one selected from the group consisting of an adhesive and a primer to the surface C of the washed plastic to obtain a laminate.
It is mentioned as one of the modes preferred to apply adhesives to the above-mentioned surface C.

(adhesive)
The adhesive that can be used in step 3 is not particularly limited. For example, urethane adhesives, epoxy adhesives, acrylic adhesives, modified silicone adhesives can be mentioned.
Among them, a urethane-based adhesive is mentioned as one of the preferred embodiments.
The urethane adhesive is not particularly limited. For example, a urethane adhesive having a polyisocyanate compound (for example, a urethane prepolymer) and a polyol can be mentioned.

(Polyisocyanate compound)
The polyisocyanate compound contained in the urethane adhesive is not particularly limited as long as it has two or more isocyanate groups in the molecule.
As polyisocyanate compounds, for example, tolylene diisocyanate (TDI; for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate), diphenylmethane diisocyanate (MDI, for example, 4,4'-diphenylmethane diisocyanate, 2, 4'-diphenylmethane diisocyanate), 1,4-phenylene diisocyanate, polymethylene polyphenylene polyisocyanate, xylylene diisocyanate (XDI), tetramethyl xylylene diisocyanate (TMXDI), tolidine diisocyanate (TODI), 1,5-naphthalene diisocyanate (NDI) ), Aromatic polyisocyanate compounds such as triphenylmethane triisocyanate; hexamethylene diisocyanate (HDI) , Trimethyl hexamethylene diisocyanate (TMHDI), lysine diisocyanate, norbornane diisocyanate (NBDI), trans-cyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI), bis (isocyanatomethyl) cyclohexane (H ₆ XDI), dicyclohexylmethane diisocyanate (H Aliphatic and / or cycloaliphatic polyisocyanates such as ₁₂ MDI); their carbodiimide-modified polyisocyanates; their isocyanurate-modified polyisocyanates; urethane prepolymers.

(Polyol)
Examples of the polyol contained in the urethane adhesive include polyether polyol; polyester polyol; polymer polyol having a carbon-carbon bond in the main chain such as acrylic polyol, polybutadiene diol, hydrogenated polybutadiene polyol, etc .; Molecular polyhydric alcohols; these mixed polyols are mentioned. Among them, polyether polyols are mentioned as one of the preferred embodiments.

-Urethane prepolymer The said urethane prepolymer as said polyisocyanate compound is a polymer which has several isocyanate group in 1 molecule. The urethane prepolymer preferably has an isocyanate group at the molecular end. As the urethane prepolymer, conventionally known ones can be used. For example, the above polyisocyanate compound (a compound other than a urethane prepolymer) and a polyol (for example, a polyol contained in the above urethane adhesive) are reacted such that the isocyanate group is excessive to the hydroxy group of the polyol. The reaction product etc. obtained by carrying out can be used.

  The urethane prepolymer is preferably a urethane prepolymer obtained by reacting a polyether polyol and an aromatic polyisocyanate compound from the viewpoint of being excellent in adhesiveness and curability.

(Primer)
The primer which can be used in step 3 is not particularly limited. For example, conventionally known ones can be mentioned. Specifically, for example, a composition containing a phenol resin, an epoxy resin, a urethane resin or an acrylic resin is mentioned. The primer can be selected depending on the adhesive and / or the substrate (plastic).

(Laminate)
In step 3, at least one selected from the group consisting of an adhesive and a primer can be applied to the surface C to obtain a laminate.
The method of application is not particularly limited. For example, a conventionally known method of application can be mentioned.

  Also, after the application, the adhesive can be cured or the primer can be dried at room temperature or under heating conditions. The temperature conditions can be appropriately determined by the adhesive or primer used.

  The laminate has the cleaning plastic and a layer formed of at least one selected from the group consisting of an adhesive and a primer.

Moreover, the said laminated body can have another base material further on the layer containing an adhesive agent at least.
Examples of the other substrate include glass, rubber, plastic and metal.
When the other substrate is a dry-treated plastic, it is preferable to subject the dry-treated plastic as the other substrate to the treatment of the step 2 from the viewpoint of better adhesion.
Examples of the layer containing at least the adhesive include a layer having only an adhesive; a layer having two layers of an adhesive and a primer; and a layer having three layers of a primer, an adhesive and a primer.

  As a laminate having another substrate, for example, a laminate having a layer containing at least the above-mentioned adhesive between two of the above-mentioned cleaning plastics (this may be hereinafter referred to as "two plastics") Can be mentioned.

As a method of producing a laminate having the layer containing at least the adhesive between the two plastics, for example, the two plastics are respectively produced according to the step 1 and the step 2 (the two plastics are May be the same or different.) Apply at least an adhesive to at least one of the two plastics according to step 3 above. Next, after the step 3, further, in the step 4, a layer containing at least the adhesive between the two plastics by laminating the adhesive-coated cleaning plastic and the remaining cleaning plastic. Can be produced.
After the above bonding, the adhesive can be cured at room temperature or under heating conditions.

  The manufacturing method of the present invention can be applied to, for example, assembly of automobile parts.

Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to these.
[Examples 1 to 7, Comparative Examples 1 to 5]
<Step 1>
For each example, six glass fiber-filled composite polypropylenes (trade name R-200G, manufactured by Prime Polymer Co., length 12 cm, width 2.5 cm, thickness 3 mm) were prepared as a substrate (plastic).
The substrate was subjected to plasma treatment under the following plasma treatment conditions using a product name FG3001 (radiation nozzle RD1004, manufactured by Plasma Treat Co., Ltd.) as a plasma treatment apparatus to obtain a plasma-treated plastic.

(Plasma processing conditions)
The plasma processing conditions are as follows.
・ The distance between the above substrate and the radiation nozzle: 5 mm
Processing speed: 80 mm / sec Pass number: 1 pass Device output: 210,000 kHz
Source gas: dry air

(Wet tension of surface B of plasma treated plastic)
The wetting tension of the surface B of the plasma-treated plastic was measured under room temperature conditions according to JIS K 6768: 1999 “Plastic-film and sheet-wetting tension test method”. A wet tension test mixture (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a test mixture.
The wetting tension of each plasma-treated plastic was confirmed to exceed 65 mN / m.
In Table 1, the wet tension "73 mN / m" of the surface B means that the wet tension of the surface B is 73 mN / m or more.

<Step 2>
(Preparation of cleaning tool)
As a washing | cleaning base material, the brand name Bencott (made by Asahi Kasei company. Cupra continuous long-fiber non-woven fabric. Weight per sheet is 0.6 g) was used.
Each cleaning tool was prepared by including the solvents shown in Table 1 in the cleaning substrate. In Comparative Examples 1 and 5, no solvent was used. In addition, organic solvents other than distilled water described in the "solvent contained in washing | cleaning tool" column of Table 1 are all commercial items.
The weight of each cleaning tool was 4.5 to 3.0 g per sheet.

(Treatment using cleaning tools)
The surface B of the above plasma-treated plastic was wiped once in one way with one cleaning tool prepared as described above while applying a force of 7.5 kPa to the surface, to obtain a washed plastic.
In Comparative Examples 1 and 2, the plasma-treated substrate is not wiped with the cleaning tool.
In Comparative Example 2, instead of wiping with a cleaning tool, the plasma-treated substrate was immersed in distilled water, and after the immersion, it was removed from distilled water and air-dried.

(Wet tension of surface C)
The wetting tension of surface C of each washed plastic obtained as described above was measured in the same manner as described above. The results (average values of the wetting tensions of the six washed plastics) are shown in Table 1.
In Table 1, the wet tension "73 mN / m" of the surface C means that the wet tension of the surface C is 73 mN / m or more.

<Step 3>
(adhesive)
As the adhesive, a urethane-based adhesive (a main agent containing a urethane prepolymer: WS-242, a polyol-based curing agent: AN-1, all manufactured by Yokohama Rubber Co., Ltd.) was used. The above main agent: the above curing agent (mass ratio) was used at 10: 1, and these were mixed to form an adhesive.

(Laminate)
The above-mentioned six cleaning plastics were used in pairs in each example to produce three laminates.
The above adhesive was applied to the surface C of one of the two cleaning plastics used in each laminate, one of the cleaning plastics.
Another cleaning plastic was overlaid on the adhesive coated cleaning plastic. Specifically, the two pieces of cleaning plastic were pasted so that the surfaces C face each other, and the two cleaning plastics overlap each other by 1 cm in the longitudinal direction (the thickness of the adhesive after lamination is 3 mm). After superimposing the washed plastic as described above, it was aged for 3 days under room temperature conditions to obtain a laminate.

[Example 8]
A laminate was manufactured in the same manner as Example 1, except that the plasma treatment conditions in the above Step 1 were changed to the following. The wetting tension (average value) of the plasma-treated substrate was 58 mN / m.
・ The distance between the above substrate and the radiation nozzle: 15 mm
Processing speed: 175 mm / sec Pass number: 1 pass Device output: 210,000 kHz
Source gas: dry air

<Evaluation>
A shear test was performed using the laminate produced as described above to evaluate adhesive strength and failure mode. The results are shown in Table 1.
The shear test was performed under the conditions of a tensile speed of 50 mm / min and 20 ° C. according to JIS K 6850: 1999.
Three laminated bodies were produced in each Example and comparative example as mentioned above, and each laminated body was evaluated.
In each Example and comparative example of Table 1, the average value of the evaluation result of said 3 laminated body was shown about each evaluation item.
In the evaluation of failure mode, CF means cohesive failure of the adhesive, and AF means interface failure between the adhesive and the substrate surface. The numerical value in the "CF" column is the ratio (%) of the area of CF to the entire bonded area. The numerical value in the "AF" column is the ratio (%) of the area of AF to the entire bonding area.

As is clear from the results shown in Table 1, Comparative Example 1, in which the plasma-treated plastic was not wiped with a predetermined cleaning tool and was used as it was, had low adhesion.
Instead of wiping the plasma-treated plastic with a cleaning tool, it was immersed in distilled water, and after the immersion, it was removed from the distilled water and air-dried, and Comparative Example 2 had low adhesion.
Comparative Examples 3 and 4 wiped with a cleaning tool containing a nonpolar solvent had low adhesion.
Comparative Example 5 which was wiped with a cleaning substrate without wiping with a predetermined cleaning tool had low adhesion.

  On the other hand, according to the manufacturing method of the present invention, a laminate excellent in adhesiveness was obtained.

(XPS analysis)
The surface a of the plastic before dry processing used in Example 1, the surface b of dry processed plastic after step 1 (after dry processing), and after step 2 (after wiping with a cleaning tool) The surface c of the plastic was analyzed by X-ray photoelectric spectroscopy (XPS). The results are shown in the attached FIG. The present invention is not limited to the attached drawings.
FIG. 1 is a graph showing the results of XPS analysis of the surface of each plastic used in Example 1.
In FIG. 1, the open bar graph represents the result of the surface a, the hatched bar represents the result of the surface b, and the black bar represents the result of the surface c.
Comparing the composition of the element forming the surface b with the composition of the element forming the surface c, carbon forming the surface c is more than the surface b, and oxygen forming the surface c is less than the surface b.
As described above, the surface c is different from the surface b in the composition of the element.
It is considered that this is because the short polymer layer on the surface b was removed by wiping the surface b with a predetermined cleaning tool in Step 2, and the surface c appeared.
On the surface c, as in the case of appropriate processing by dry processing, a polymer which is hydrophilized and has a long molecular chain is present, and since the wetting tension of the surface c is in an appropriate range, it is considered to be excellent in adhesion.

Claims (11)

Dry-treating the plastic surface A to obtain a dry-treated plastic having the dry-treated surface B;
Wiping the surface B with a cleaning tool containing at least one selected from the group consisting of water and a polar solvent to obtain a cleaning plastic having a surface C wiped with the cleaning tool;
At least one selected from the group consisting of an adhesive and a primer is applied to the surface C, and a step 3 of obtaining a laminate is provided.   The plastic is selected from the group consisting of polyolefin, polyethylene terephthalate, polymethyl methacrylate resin, polycarbonate resin, polystyrene resin, acrylonitrile styrene copolymer resin, polyvinyl chloride resin, acetate resin, acrylonitrile butadiene styrene resin, polyester resin and polyamide resin The manufacturing method of the laminated body of Claim 1 which is at least 1 sort (s).   The method for producing a laminate according to claim 1 or 2, wherein the dry treatment is at least one selected from the group consisting of plasma treatment, corona treatment, flame treatment, intro treatment, ultraviolet treatment and excimer treatment.   The method for manufacturing a laminate according to any one of claims 1 to 3, wherein in the step 2, the surface B is wiped with the cleaning tool by applying a force of 25 to 0.25 kPa to the surface B. .   The manufacturing method of the laminated body of any one of Claims 1-4 in which the said washing | cleaning tool contains water.   The manufacturing method of the laminated body of any one of Claims 1-5 which provides an adhesive agent to the said surface C.   The manufacturing method of the laminated body of any one of Claims 1-6 whose wetting tension of the said surface B is 39 mN / m or more.   The manufacturing method of the laminated body of any one of Claims 1-7 whose wetting tension of the said surface C is 34-65 mN / m.   The manufacturing method of the laminated body of any one of Claims 1-8 whose fall width to the wetting tension of the said surface C from the wetting tension of the said surface B is 5-20 mN / m.   The manufacturing method of the laminated body of any one of Claims 1-9 whose wetting tension of the said surface B exceeds 65 mN / m.   The manufacturing method of the laminated body of Claim 10 whose wetting tension of the said surface C is more than 45 mN / m and 65 mN / m or less.