JPH0291181A - Toughened rubber base hot-melt adhesive composition for binding of book - Google Patents

Abstract

PURPOSE: To form a film aggressive tack in the forming point of a binding margin adhesion, and efficiently form a binding margin by forming the binding margin on a book block in a prescribed form by use of a fused film of a specified hot melt adhesive.

CONSTITUTION: In a method of forming a binding margin on a bound book block comprising steps of laying a fused film of hot melt adhesive on an outside sheet on both sides of a book block within the length adjacent to the binding margin end on the vicinity area of the binding margin end, putting a cover thereon, and applying a pressure onto the cover of a book in this area of the hot melt film, a hot melt adhesive described below is used. Namely, the adhesive is formed of a composite obtained by blending (a) 10-40 wt.% of a radial styrene-butadiene block copolymer having a styrene content of 35 wt.% or more, an elasticity in 300% elongation of 4.5 MPa, and a solution viscosity of 1,000 cP or less, (b) 20-65 wt.% of a compatible adhesion imparting resin, (c) 0.1-4 wt.% of a stabilizing agent, and (d) the remainder (up to 100%) of a plasticizing oil.

COPYRIGHT: (C)1990,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a reinforced pressure-sensitive hot melt adhesive used for forming binding margins for soft bound books.

BACKGROUND OF THE INVENTION Flexible or softcover books are generally made of a series of printed materials or folded bound edges that form a book block that forms the spine of the book by applying a paperback or other suitable cover. Formed by coating a layer of hot melt adhesive. This process provides a first bond to the cover of the book block, while a second bond is often formed at the binding margin of the cover.

This bond is produced by applying a small amount of adhesive to the book block near the binding area. In practice, the binding process involves applying adhesive to the book block before fixing the cover, and then at several points in the manufacturing operation.
The formation is done in two different stages by applying pressure to the book cover in the downline. The purpose of applying this adhesive is to hide and strengthen the adhesive bond, and to prevent the book from coming off relatively easily just by squeezing the soft cover.

The adhesive used in this application must have various properties, in particular the adhesive of the invention must be easy to apply and provide a strong adhesive at the point of formation of the seam adhesive.
low density (i.e., low density (i.e., resistant tack), good adhesion to different cover materials, and creep resistance and cold flow resistance at both ambient and elevated temperatures.
(viscosity of about 500 to 5.000 cps at 350°F). Traditionally used adhesives are
Generally, they were non-pressure sensitive hot melt adhesives or emuldigon adhesives used in bookbinding operations. Both types of adhesives have the disadvantage that they have in common a relatively short air drying time, ie, short time to find a bond. This air-drying time drawback poses a significant problem in automated bookbinding processes where production line interruptions, reductions or stoppages result in loss of vines and subsequently require large amounts of semi-finished product. Another problem arising from the limited air drying time of prior art adhesives is that
High failure rates due to poorly formed seams caused by the relatively heavy coating weight that must be applied to ensure the presence of residual tassels, which is necessary when the seam formation time involves low machine speeds. rate. A supplementary failure is when a preferred light coating weight is used at high production speeds, but the machine in the bonding line slows down or stops because the light coating weight solidifies before bond formation and therefore no bond is formed. Occasionally limited air drying time may occur due to product.

SUMMARY OF THE INVENTION The present inventors have disclosed a pressure sensitive hot melt adhesive composition made from an adhesive consisting of styrene and butadiene arranged in a substantially radial configuration and containing at least 35% by weight styrene moieties. It was found that this method is effective in forming a binding margin with a soft ratio.

Accordingly, the present invention provides for applying a molten film of hot melt adhesive onto the outer sheet on each side of the book block over the area proximate the seam edge and for a length substantially adjacent to the seam edge; A method of forming a binding margin on a bound book block comprising the steps of applying a cover and applying pressure on the book cover in said area of said hot melt film, said hot melt adhesive comprising: (a) Styrene content is 3135% by weight or more, 300%
Substantially radial styrene-butadiene block copolymer 1 having an elastic modulus at elongation of at least 14.5 MPa and a solution viscosity of 1.0OOCI)S or less
0 to 40% by weight, (b) Miscible tackifying resin 20-, . 65% by weight, (
c) 0.1 to 14% by weight of stabilizer, and (d) the balance (up to 100%) consisting of plasticizing oil.

The block copolymers useful in this invention consist of styrene and butadiene arranged in a substantially radial configuration and contain at least 35% by weight, and generally up to about 50% by weight, styrene moieties.

However, it is very important that the copolymer chosen has a modulus of elasticity at 300% elongation of at least L 5
MPa, and the solution viscosity (25
Brookfield in %
d) Viscosity at 23 °C using a viscometer) is I, 0
Must be less than or equal to OOcps. These copolymers are described, for example, in US Pat. No. 3,239. ll'78, 3,421.269, 3.700.633
No. 3,932,327 and the like. Alternatively, the copolymer is commercially available from 5hell Chemical Co., under the trade name Kraton DXN22 (37% styrene, modulus LL, 8 MPa, viscosity 670 cps), available from Eur.
oprene 5QLT +62LW/+ (styrene 4
0%, elastic modulus 5.0 MPa, viscosity 750 cps) or SQL T +62LW/2 (Styrene 40
%, modulus it, 6 MPa, viscosity 6110 cpS) by Eni Chem Americas (Agi
It can be purchased from p USA engineering nc, ).

The optimum use of copolymers for use in adhesives varies depending on the end use application, but the copolymers are generally present in the adhesive composition at 10 to 140% by weight, preferably 15 to 25% by weight.

Tackifiers used in adhesive compositions can be hydrocarbon resins, hydrogenated hydrocarbon resins, synthetic polyterpenes, rosin esters, natural terpenes, and the like.

More specifically, effective tackifiers include (1) natural or modified rosins, such as gum rosin, wood rosin, tall oil rosin, distilled rosin, hydrogenated rosin, second generation rosin, and polymerized rosin; ) of natural or modified rosins, such as glycerol esters of pale blue wood rosins, glycerol esters of hydrogenated rosins, glycerol esters of polymerized rosins, pentaerythritol esters of hydrogenated rosins, and phenol-modified pentaerythritol esters of rosins; Pentaerythritol ester, (3) e.g. styrene/
Polymers and terpolymers of natural terpenes such as terpenes and α-methylstyrene/terpenes, (4) AS
Softening point measured by TM method E28-587 80-1
Polyterpenes (the above polyterpenes are polymerization of terpene hydrocarbons such as the bicyclic monoterpene known as pinene in the presence of a Friedel-Krach catalyst at moderately low temperatures to -III) with a temperature of 50 °C. (also includes hydrogenated polyterpenes), (5)
Phenol-modified terpene resins and derivatives thereof, such as, for example, resin compositions obtained by condensation of bicyclic monoterpenes and phenols in acidic media, (6)
Aliphatic petroleum hydrocarbon resins having a ring and ball softening point of 70 to 135°C (the above resins are obtained by polymerization of monomers mainly consisting of olefins and diolefins, and also include hydrogenated aliphatic petroleum hydrocarbon resins) ), (7) aromatic petroleum hydrocarbon resins and derivatives thereof, and (8)
There are cycloaliphatic petroleum hydrocarbon resins and their derivatives. Mixtures of two or more of the above tackifiers are required in some compositions. Tackifiers are used in amounts of 20-65% by weight.

The remainder of the hot melt adhesive (up to about 60% by weight) consists of at least one oil diluent. Suitable plasticizing or extending oils include not only conventional plasticizing oils but also olefin oligomers and low molecular weight polymers and vegetable and animal oils and their derivatives. The petroleum-derived oils that can be utilized are relatively high-boiling materials that contain only a minor portion of aromatic hydrocarbons (preferably not more than 30%, especially not more than 15% by weight of the oil). Alternatively, the oils may be wholly non-aromatic. The oligomer may be polypropylene, polybutene, hydrogenated polyisoprene, hydrogenated polybutadiene, etc. with an average molecular weight of 350 to 10.000. Among the stabilizers or antioxidants included in the present invention, high molecular weight hindered phenols and polyfunctional phenols, such as sulfur- and phosphorus-containing phenols, are preferred.

Hindered phenols are known to those skilled in the art and can be characterized as phenols that also contain a sterically sparse radical in the vicinity of their phenolic hydroxyl group. In particular, a tertiary-butyl group is generally substituted on the benzene ring in at least one position ortho to the phenolic hydroxyl group. The presence of these sterically sparse radicals around the hydroxyl group increases the stretching frequency
ncy) and correspondingly its reactivity. That is, this steric hindrance provides the phenolic compound with its stability. Typical hindered phenols include 1,3,5-trimethyl 2,4
．． 6-tris(3,5-di-t, ert-butyl-4-
hydroxyl)benzene; pentaerythritol tetrakis-3(3,5-di-tert-butyl-4-hydroxyl)propionate; n-octadecyl-3,5-
Di-tert-butyl-4-hydroxyphenol) propionate; J4.11'-methylenebis(2,6-
tert-butylphenol); “+”-thiobis(6-7 ert-butyl-〇-cresol); 2.6
-tert-butylphenol; 6-(IL-hydroxyphenoxy)-2,14-bis(n-octyl-thio)-+, 315-triazine; di-n-octadecyl 3,5-di-tert-butyl-4-hydroxybenzyl Phosphonates; 2-(n-octyl-thio)ethyl 3,5-di-tert-butyl-4-hydroxybenzoate; and sorbitol hexa[3-(3,5-di-tert-butyl-4-hydroxyphenol)propionate]. . The above stabilizer is 0.1 to 4
It is present in an amount of up to about 2% by weight, preferably about 2% by weight or less.

Optional additives may be added to the hot melt composition to improve its properties. Such additives include colorants such as titanium dioxide, fillers such as talc and clay, and small amounts (eg, about 5% or less) of petroleum-derived waxes.

These hot melt adhesive compositions may be formulated using techniques known in the art. As an example of operation,
A jacketed kettle, preferably equipped with a rotor, raises the temperature to a range of 250 to 350 degrees Fahrenheit (the exact temperature utilized depends on the melting point of the particular tackifier).
- Includes blending approximately half of the total tackifying resin concentration in a Perkins or Day type jacketed high-intensity mixer. Begin stirring when the resin has melted, and add the block copolymer and stabilizer together with any additives (although their presence is optional, and the addition of the latter component is delayed over a long period of time to avoid the formation of lumps). Add. Continue stirring and heating until the remaining tackifier and oil are thoroughly and evenly mixed to obtain a smooth and uniform mass. The resulting hot melt adhesive composition is generally manufactured as a bulk oil and packaged in release coated tubes or boxes.

EXAMPLES In the following illustrative examples, all parts are by weight and all are in degrees Celsius, unless otherwise specified.

Example! The following examples illustrate the preparation of adhesives of the invention in formulations suitable for use in the disposable industry as described above.

In the preparation of the following samples, an intensive mixer heated to 150°C and fitted with a stirring blade was filled half with tackifying resin. After melting the resin, then start stirring,
Block copolymer and antioxidant were added slowly.

Stirring and mixing were continued until a homogeneous mass was obtained, to which the remaining tackifying resin and oil were added.The molten mixture was then poured into a siliconized paper tube and cooled to room temperature.

Adhesives were prepared from the materials and amounts listed in Table 1 using the general method described above. Viscosity measurements were made using a Brookfield viscometer (spindle 27) at 325″F.
The following tests were conducted to examine the heat resistance of the adhesive under constant load and static stress as well as elevated temperatures.

The adhesive was heated to 150" and lamination of the kraft paper was done using a heated roller. The adhesive was 50 mils thick and the bond had an adhesive area of 1 square inch. This bond was 72'F' and 50%R
Aged overnight in H. Peel mode sample then 3
It was hung open at 105°F using a weight of 0.00 g/in2. The time at which the bond failed was recorded as the mode of failure.

The tensile strength of the hot melt adhesive was measured on samples cast from the hot melt and formed into dogbone shapes in silicone rubber molds. After cooling, the dogbone configuration specimens were demolded and tested using an In5tron Ten5ile Te5ter at a strain of 12 inches per minute. The time required to begin stretching the specimen was recorded as the "tensile yield" and the maximum force reached was recorded as the "ultimate tension".
shall be. This method results in the measurement of percent elongation, which is the percentage of the elongation of the hot melt sample at the point of break obtained at ultimate tension.

Note: +) Permalyn 305 is Hercule
Rosin pentaerythritol ester from Company S.

2) 5tereon 8110A is Firest
Contains 143% styrene from one company, elastic modulus 2.4M
It is a styrene-butadiene multiblock copolymer with Pa and solution viscosity of 650 cps.

3) Firestone SR7360 is 43%
Contains styrene, elastic modulus 3.7 at 300% elongation
Styrene with MPa and solution viscosity 990 cps
It is a butadiene polymer.

4) ECR+119B is Exxon's aliphatic/
It is an aromatic C5/C9 resin. (Softening point 95°C)
.

5) ECR+l19A is Exxon's aliphatic/
It is an aromatic C5/C1 resin. (Softening point 105°C)
.

6) Kr1stalex 51110 is [-1e
It is α-methylstyrene resin manufactured by Rcules. (Softening point: 140°C).

7) M+05 is a styrenated terpene from Relhold.

8) RES D: l'105) lercules
It is a styrenated chirhenyl produced by the company.

9) SR, a liquid tackifying resin from Exxon
It also contains 3 parts of 31l13H.

The test results for Samples 1-8 show that the adhesives of the present invention have significantly higher intrinsic viscosities when compared to currently commercially available adhesives containing similar amounts of raw materials.

Sample 9 shows that low viscosity adhesives can be obtained using small amounts of polymer without loss of tensile strength. (
Sample 11 manufactured using 15 parts of Stereon
). Note, however, that this product has drawbacks with respect to kraft/kraft adhesion and is therefore not immediately useful for certain end-use applications requiring direct forced heat resistance.

Samples 12, 13 and 14 show similar results to sample 9 and additionally show that the use of different tackifiers overcomes the shortcomings of sample 9 with respect to heat resistance.

Sample 17 shows another formulation according to the invention using a different tackifying system. Particularly noteworthy is its high heat resistance value.

Samples 18 to 26 are again conventionally used S
Samples 214.25 and 26 demonstrate that improved thermal resistance and ultimate tensile strength are achieved with the adhesive compositions of the present invention compared to reon or Sol T+68; 1122X
This shows that low viscosity products can be obtained without loss of tensile strength.

During testing, all samples 1-22 completely gave a cohesive mode of failure in the Kraft-to-Kraft heat resistance test, i.e., adhesive residue was observed on both supports after bond failure. .

The resulting adhesive can be used to form a binding margin using methods customary in bookbinding techniques without being restricted to a particular application. Thus, book blocks can be bound, for example, but not limited to, completely with hot-melt adhesive, burst-bound with emulsion adhesive, followed by true-melt adhesive;
Binding can be done by any of the conventional methods such as emulsion adhesive emulsion and descaling or emulsion adhesive full binding. The binding margin can be applied to any book, configuration, i.e. a book that is finally hard glued or glued to the cover, and a flexible or soft cover book where the binding margin is formed between the book block and the final bound page. Or formed into book blocks.

Generally, regardless of the method of construction, a film of non-pressure sensitive adhesive is applied to the densified edges of the book blocks, and then a molten film of the aforementioned hot melt pressure sensitive adhesive is applied to the area adjacent the bound edges. a soft cover is applied to the first film with the latter remaining unbound, and pressure is applied to the outer sheet on both sides of the book block between the lengths substantially adjacent to the top and width edges; Apply the area of pressure sensitive hot melt adhesive to the book cover to form a binding margin. Alternatively, the binding hotmelt may be applied to the soft cover in a suitable line such that the cover is fed into the binder alongside the book block.

Proceedings (Published in November 1989 by the Commissioner of the Japan Patent Office Yoshi 1) Takeshi Moon 1, Indication of the case 1999 Patent Application No. 199523 2, Name of the invention Reinforced rubber-based hot melt adhesive for wood binding substitute Agent Composition 3, Relationship with the Amendment Case Applicant Name: National Starch & Co., Ltd. Address: 2-8-1 Toranomon, Minato-ku, Tokyo (Toranomon Electric Building) [Telephone: 03 (502) 1476 (Representative) 16. Contents of amendment (1) The scope of claims is amended as shown in the attached sheet.

(2) Add the following sentence after line 19 on page 21 of the specification.

rThe present invention relates to each claim described in the claims, and includes the inventions described below as embodiments.

(1) The tackifier in the hot melt pressure sensitive adhesive composition is (1) natural and modified rosins, (2)
Glycerol and pentaerythritol ester necks of natural and modified rosins; (3) copolymers and terpolymers of natural terpenes; (4) ASTM method E2.
Polyterpene resins having a softening point of 80 to 150°C as measured by 8-58T, (5) Phenolic modified terpene resins and hydrogenated derivatives thereof, (6) Ring and ball softening point of 70 to 135°C. (7) aromatic hydrocarbon resins and their hydrogenated derivatives; and (8) alicyclic petroleum hydrocarbon resins and their hydrogenated derivatives. An adhesive according to claim 1, which is any miscible resin selected from the group or a mixture of the above resins. (Attachment) Claims: (1) Applying a molten film of hot-melt adhesive onto the outer sheets on both sides of the book block over an area in the vicinity of the binding edge and for a length substantially adjacent to the binding edge. A method for forming a binding margin on a bound book block comprising the steps of: applying the hot melt adhesive to the book cover; applying pressure on the book cover in the area of the hot melt film; (a) a substantially radial styrene-butadiene block copolymer having a styrene content of 35 wt. 1θ～
40% by weight, (b) 20-65% by weight of miscible tackifying resin, (c)
A method as described above, wherein the pressure sensitive adhesive composition consists of 0.1 to 4% by weight of a stabilizer, and (d) the balance (up to 100%) consisting of a plasticizing oil.

(2) A tree bound by the method according to claim 1.

Claims (1)

Claims: 1) applying a molten film of hot melt adhesive onto the outer sheet on each side of the book block over an area proximate the seam edge and between a length substantially adjacent the seam edge; A method of forming a binding margin on a bound book block comprising the steps of applying a cover thereto and applying pressure on the book cover in said area of said hot melt film, said hot melt adhesive comprising: a) Substantially radial styrene-butadiene block copolymers 10-4 having a styrene content of 35% by weight or more, a modulus of elasticity at 300% elongation of at least 4.5 MPa, and a solution viscosity of 1,000 cps or less
(b) 20-65% by weight of a miscible tackifying resin, (c) 0.1-4% by weight of a stabilizer, and (d) the balance (up to 100%) consisting of a plasticizing oil. The above method which is a pressure sensitive adhesive composition. 2) The tackifier in the hot melt pressure-sensitive adhesive composition includes (1) natural and modified rosins, (2) glycerol and pentaerythritol esters of natural and modified rosins, and (3) natural terpenes. Copolymers and terpolymers, (4) ASTM method E28-5
(5) Phenolic modified terpene resins and hydrogenated derivatives thereof; (6) Aliphatic resins having a ring and ball softening point of 70-135°C as measured by 8T. selected from the group consisting of petroleum hydrocarbon resins, (7) aromatic hydrocarbon resins and their hydrogenated derivatives, and (8) alicyclic petroleum hydrocarbon resins and hydrogenated derivatives thereof. An adhesive according to claim 1 which is any miscible resin or a mixture of the above resins. 3) A book bound by the method according to claim 1.