AU618741B2 - Diazabicyclo + triazabicyclo primer compositions + use thereof in bonding non-polar substrates - Google Patents

Description

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t= AU-A! 19678/68 WORLDQ INTLfLECTUAL PIIOPURTY ORGANIZATION inorwanl 1Ourvau, PCT pfti: INTRNAIONL APLCATO U4S Ln U17R Tj V3 E(fNT COOPE3RATION TRE3ATY (PCT) (S1) Interntiional Patent Cul5S~rfvtton (11 ~1 to 1110 Publicatlon Number: WO 88/ 10)289 C09J 5/04 Al (43) International Publication Dole;29Dembr18(2-.88 (21) Interalilonal Application Number: PCT/US88/02028 (81) Designiated States., AV!, 13R, JP. KR, (22) International Filing Dale: 10 Junie 198$ (10,06-88) Wi/i Internaional soarcl: re'pori.

(31) Priority Application Numberi 1637/87 (32) Priority DaOW; 19 June 19$7 (19,06,87) (33) Priority Country: 113 A. 0,J.1? 16 MAR 198 (71) A 1atLOCTITI3 CO RP0ORATIO N (LJS/USI:, 705 ASRLA Mi.)rth Mountain Road, Newington, CT 06111 UTRLA (72) Inventors: McDONNI3LL, Patrick 31 Parkmore Drive, 19 JAN 1989 Terenure, Dublin 6 (113). KNEiAFSEY, Brendan, J. 31 Wespark, Tallaght, Dublin 24 PATRNV OFFIC17 (74) Agent,. WE3LCH, E~dward, 11: Loctite Corporatlon, 705 North Mountain Road, Newington, CT 06111

(US).

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Hi (57) Abstract ,l~pn a process for priming a non-polar substrate such as a polyolef in for bonding with a cyanoacrylate adhesive, the use o(an adhesion-promoting primer comprising at least one diazabicyclo or triazabicyclo compound selected from azabcclo[4.3.O1non-5-one having formula I,8-diazabicyclo[5.4,Ojuindec-7-ene having formula (1I) and 1,5,7-triazabicy~ql6[4.4,O]dec-5-ene having formula (111). The primer also contains a solvent.

pCT1S88102028 WO 88/10289 bZ42A?_ARYc.yc AV( Tgz4ZAi8.r-YCL0 Ptrmvir CoMVf OVrOAIS 4WI U6 TII6COF -PV &6AIPX1 MJON-PoL/i& YO6WTg47TU _~.TZ4-4Rn nr A nrtJr.. r'lmT~ nInT~rl~-4 wr m m.wa at I- IYLL *Ivl cul~r orhl~CIIf~ 1 Background of the Invention Field of the Invention The present invention relates to use of a primer to promote the bonding of non-polar or highly crystalline substrates with adhesives, especially with cyanoacrylate adhesives. In particular, the primer of the present invention promotes bonding of polyolefins or similar plastic substrates with low surface epergy.

Because of their low surface energy non-polar materials are difficult to bond, even with cyanoacrylate adhesives. These materials are represented by linear polymers of simple olefins, such as polyethylene, polypropylene, polybutene and the like, including their copolymers. Other materials which can be bonded by this invention are substrates having low surface energy such as polyacetals, plasticized PVC (polyvinyl chloride), polyurethane, EPDM (ethylene-propylene diamine monomer) rubber, thermoplastic rubbers based on vulcanized polyolefins and the like.

Th2 materials bonded by this invention have, in general, a waxy, paraffin-like surface character, with a low critical surface tension of wetting and may have at their surface a weak boundary layer. In general, there is an absence of polar groups which are necessary to raise the surface energy to the level needed to give adhesion with conventional adhesives.

./fJ 4 WO 8811289 PCT/US88/02028 2 Description of the Prior Art Various surface treatments have been used heretofore to improve adhesion of the difficult-to-bond materials described above. These treatments include surface abrasion, corona discharge Von der Hoide H.L. Wilson, Modern Plastics ,U 9 (1961) p199), flame treatment Buchel, British Plastics 1Z (1964) p142), U.V. radiation (Practising Polymer Surface Chemistry, D. Dwight, Chemtech (March 1982) p166), plasma treatment, hot chlorinated solvents, dichromate/sulphuric acid and chlorine/U.V. radiation (D.Brewis D.Briggs, Polymer 22 7 (1981) and references therein). All the above treatments are effective to some degree and are generally thought to work by introducing polar groups on non-polar substrates.

While the above treatments may, on occasion, improve the ability of difficult substrates to be bonded with adhesives, the treatments have the disadvantage of requiring specialized apparatus and equipment and can involve corrosive and/or hazardous materials.

Apart from the above treatments, there are examples in the prior art of the use of various accelerators or initiators of the polymerization of the cyanoacrylate monomer. The disadvantage with such accelerators or initiators is that while the speed of cure of the bond is increased, adhesion on non-polar substrates is not promoted and the resulting bond can be very weak and the adhesive can slip off the substrate.

An accelerator comprising a solution of certain amines and a deodorant is disclosed in Japanese Patent Application No. 599066471-A. United States Patent No. 3 260 637 of Von Bramer discloses the use of various classes of organic amines (but specifically excludes primary amines) as accelerators in conjunction with cyanoacrylate adhesives. The compositions of both of these specifications can best be described as accelerators or initiators of the polymerization of cyanoacrylate monomer without improving adhesion on non-polar substrates.

Various primers also have been proposed to promote adhesion. For example, Japanese Patent Applications Nos. 52-98062, 56-141328 and 57-119929 suggest the use of primers prepared by dissolving a II 1 _1 WO 8810289 PCT/US88/02028 3 chlorinated polyethylene or chlorinated polypropylene or a fatty acid-modified acrylated alkyd resin in an organic acid, In general, however, organic acids tend to inhibit or prevent curing of cyanoacrylate adhesives. The primer of the present invention has the advantage of using a low molecular weight material which is readily soluble in common solvents.

European Specification No. 0 129 069 A2 discloses the use of a primer comprising at least one organometallic compound, for use with alphacyanoacrylate adhesives, which is useful in bonding non-polar substrates. Japanese Application No. 61023630 proposes organometallic primers for joining plastic models, Both of these documents discTose the use of organo-metallic compounds which are potentially highly toxic materials.

Primers for polyolefins comprising modified or grafted polyolefins such as chlorinated polyolefins, ethylene/vinyl copolymer or ethylene/propylene terpolymer, (ii) a crosslinkable binder and (iii) crosslinking agents, are disclosed in European Application No.

187171A. The primer described there is somewhat inconvenient to use and apply due to its rubbery consistency, and heating may be needed to activate the primeron the substrate. In addition the solvents used toluene and 1,1,1-trichloroethylene) have an undesirable toxicity.

German Application No. DE 3601518-A suggests the use of primers for polyolefins comprising an organometallic compound and an organic polymer; the organometallic compound being a metal alcoholate and the term "metal" including metalloids, phosphorous, boron or silicon atoms. The materials disclosed such as dibutyltin diacetate and other organo-metallic compounds are highly toxic for use as primers.

Japanese Application No. 61136567 describes a titanate primer for bonding polypropylene. The titanate primers give little or no improvement when bonding difficult materials, such as polyethylene, to itself or to other materials, when cyanoacrylate adhesives are employed, Japanese Application No. 60157940 discloses a primer composition based ae on a solution of 4-vinyl pyridine as an essential ingredient, and 3, 4-lutidlne as an optional ingredient, for bonding polyolefins, polyacetal, polyamide, polyester, boron-polymer, silicone or PVC. However, the disadvantage with the primer of Japanese Application No, 60157940 is that it has a strong odour and, in addition, it does not produce as strong a bond as that produced by the primer of the present invention.

Object of the Invention It is an object of this invention to provide a primer which is useful in bonding non-polar plastics to themselves, or to other substrates, using adhesives, especially cyanoacrylate adhesives.

Summary of the Invention In a method of bonding a non-polar substrate to another substrate which may be polar or non-polar, which comprises treating the non-polar substrate or substrates with an adhesion-promoting primer comprising at least one diazabicyclo or triazabicyclo compound selected from; 1,5-diazabicyclo[4.3.0]non-5-ene having the formula:

N

1,8-diazabicyclo[5.4.0]undec-7-ene having the formula:

N

and 1,5,7-triazabicydlo[4.4.0]dec-5-ene having the formula:

H

N N

(II)

applying an alpha-cyanoacrylate adhesive to the substrate or substrates and then adjoining the two substrates.

In a further aspect of the invention there is provided an adhesionpromoting primer composition for use in bonding non-polar substrates.

-4- WO 8/10289 CT/US88/02028 anl(M 6rTt^^M^< 4,r-ec^~ene-avi ng-the-formul-a{-- N N Preferably the primer also comprises an organic solvent in which the azabicyclo compound is stable, such as acetone, methyl ethyl ketone, 1,1,1,-trichloroethane, methanol, 1,1,2-trichloro-1,2,2,-trifluoroethane or mixtures thereof with each other or with other solvents 'such as an azeotropic mixture of 1,1,2-trichloro-1,2,2,-triflourethane with acetone. The function of the solvent is to provide a suitable concentration of the azabicyclo compound so that a coating of selected thickness can be applied to a surface. Therefore, any common solvent in which the compound is stable will suffice.

While it is well known that solutions of amines and other organic and inorganic bases will accelerat .the cure of cyanoacrylate adhesives, it is surprising that the primers.-f-this invention also confer adhesion on non-polar substrates. The curing or polymerisation of a film of cyanoacrylate, between two materials, does not necessarily result in a strong bond, particularly if the materials are non-polar, and if the polymerisation of the cyanoacrylate is excessively rapid, a very weak bond or no bond will result.

The primer composed of one of the above diazabicyclo or triazabicyclo compounds as a solution in a solvent is normally of such concentration that the thickness of the coating can be controlled to achieve the full effects of this invention.

It is preferable that a solution of the diazabicyclo or triazabicyclo compound in the solvent should have a concentration of 0.001 weight/volume. Preferred concentrations are 0.01 2% weight/volume.

The invention also provides a 2-part adhesive system comprising an S4-, alpha-cyanoacrylate adhesive and (ii) a primer as defined above.

;MV3 91 i n r err r i ,lac PCT/US88/02028 WO 88/10289 Suitable cyanoacrylate adhesives for use with the primer of this invention are represented by the general formula CH a C COORI CN (IV) wherein RI is alkyl, alkenyl, cycloalkyl, aryl, alkoxyalkyl, aralkyl, haloalkyl or another suitable group. The lower alkyl alpha-cyanoacrylates are preferred, and in particular methyl, ethyl, n-propyl, n-butyl, isobutyl, isopropyl, allyl, cyclohexyl, methoxyethyl or ethoxyethyl cyanoacrylates are preferred.

Many alpha-cyanoacrylates can be obtained commercially as one component instant adhesives, in which form they may be used in this invention.

While these commercially available cyanoacrylates are composed principally of alpha-cyanoacrylate monomer, the formulation may contain stabilizers, thickeners, adhesion promoters, plasticizers, dyes, heat resistant additives, impact resistance modifiers, perfumes and such like.

A diluted solutiontof a cyanoacrylate adhesive in a compatible solvent may also be used.

-26----n-a-f-ur-t-her--aspet-the-invent4on-r-ov4des -me-theod-f-4ni-ng-a non-polar substrate to another substrate which ma e-po-l-a1 r non-polar, which comprisesa tr -ti non-polar substrate(s) with a prime ier re a ove and then applying an alpha-cyanoacrylate o. i to -tue-b ate( In the case where the substrates to be bonded are both non-polar or otherwise difficult-to-bond materials of that type, both substrates are coated with a solution of primer. This coating may suitably be applied by brush, spray or immersion of the substrate in the primer solution.

If the non-polar substrate is to be bonded to a polar or more active substrate, only the non-polar substrate needs to be coated with the primer.

WO 88/10289 PCT/US88/02028 7 Following application of the primer to the non-polar substrate(s), the bond is completed using cyanoacrylate adhesive in the normal manner.

Bonding tests were carried out using various substrates, including natural polyethylene and natural polypropylene as the non-polar substrates, various solutions of the diazabicyclo compounds as the primer and various grades of cyanoacrylate adhesive commercially available from Loctite (Ireland) Limited, Dublin, Ireland. The bond strength of the resulting joints was determined using conventional methods, such as a tensile testing machine.

Description of the Preferred Embodiments The following examples will more clearly illustrate the invention.

EXAMPLE 1 0.50g of 1,8-diazabicyclo undec-7-ene was dissolved in 99.5 cc of Freon TA [trade mark for azeotrope of acetone and 1,1,2-trichloro-1, 2,2-trifluoroethane, available from E.I. Du Pont de Nemours Co. Inc.] to form a primer solution.

I

Test pieces of natural polyethylene of dimensions 100 mm x 25 mm and 3mm in thickness were carefully deburred and degreased with acetone.

The above primer solution was applied to the test pieces by brush to form a single coating. This coating was allowed to dry 2 minutes; and 5 minutes in air under unforced conditions. Two polyethylene test pieces, both of which were primer coated as above, were then bonded with Loctite 406 [a cyanoacrylate adhesive manufactured by Loctite Corporation, Newington, CT., The overlap bond area was 1.61 cm 2 The bonds were clamped with a force of 4.0 kg/cm 2 for 24 hours at a temperature of 22oC.

Test pieces of natural polypropylene of dimensions 100 mm x 25 mm x 3 mm were also prepared and coated with a primer solution as described above and bonded with Loctite 406 adhesive as in the above procedure.

The tensile shear bond strength was then determined on an Instron 1 I *9 3 1 1 r 7 PCT/LS88/02028$ WO 88/10289 8 testing machine at a pulling rate of 200 mm/minute according to Test Method ASTM 01002.

As a control, the above procedure was repeated except that no primer coating was applied to the test pieces.

The results are shown in Table 1.

TABLE 1 TENSILE SHEAR BOND STRENGTHS ON POLYETHYLENE AND POLYPROPYLENE [Primer Based on 1,8-diazabicyclo undec-7-ene] Coating Drying Time Run No.

Tensile Shear Bond Polyethylene/ Polyethylene Strength (Kg/cm 2 Polypropylene/ Polypropylene Primer 11 2 minutes IfI" minutes 1 47 74 2 57 62 3 37 38 Control 1 0 8 (No Primer) 2 0 9 3 0 7 [Adhesive used above was Loctite 406 which is based on ethyl-2-cyanoacrylate.] 8$/10289 T PCT/US88/02028 EXAMPLg Primer solutions were prepared by dissolving 0.50g each of non-5-ene, 1,8-diazabicyclo undec- 7-ene and 1,5,7-triazabicyclo.[4.4.0] dec-5-ene in 99.5 cc of Freon TA.

Test pieces of natural polyethylene were prepared as in Example 1 and both surfaces to be bonded were treated with a single coating of one of the above primers. The coating was allowed to dry in air for minutes. The primed test pieces were then bonded with Loctite 406 cyanoacrylate with the bonds being prepared, aged and tested as in Example 1.

Controls with no primer were also prepared.

The results are shown in Table 2.

TABLE 2 POLYETHYLENE BOND STRENGTHS WITH THE THREE PRIMERS Primer Type Run No. Tensile Shear Bond Strength (kg/cm 2 Polyethylene/Polyethylene fI 1 48 2 48 3 1,8-diazabicyclo 1 -undec-7-ene 2 68 3 62 1,5,7-Triazabicyclo 1 dec-5-ene 2 33 3 49 Control (No Primer) 1 0 3 0

I

PCT/U88/02028 I WO 88/10289 sXAMP w p3 The following primer solutions were prepared: Primer A Primer B Primer C 1.0g. of 1,8-diazabicyclo undec-7-ene dissolved in 99.0 cc of Freon TA, 0.10g. of 1,8-diazabicyclo undec.7-ene dissolved in 99.90 cc of Freon TA.

0.050g of 1,8-diazabicyclo undec-7-ene dissolved in 99.95 cc of Freon TA.

0.20g of 1,5-diazabicyclo non-5-ene dissolved in 99.80 cc of Freon TA 0.25g of 1,5,7-triazabicyclo dec-5-ene dissolved in 100 cc of Freon TA 0.05g of 1,5,7-triazabicyclo dec-5-ene dissolved in 100 cc of Freon TA.

Primer D Primer E Primer F Test pieces of natural polyethylene were prepared as in Example 1.

These were treated with a single coating of one of the above primers and allowed to dry in air for 5 minutes. Primer was applied to both surfaces to be bonded. The primed test pieces (and unprimed controls) were bonded with Loctite 406 cyanoacrylate adhesive as in Example 1.

The results are shown in Table 3.

WO 88/1t0289 PTU$/22 PCT/IUS$8/02028 PRIMER SOLUTIONS AT VARIOUS CONCENTRATIONS Run No. Tensile Shear Bond Strength (kg/cmz) Polyethylene/Polyethylene Primer A 1 56 2 3 61 Primer B 1 62 2 3 87 Primer C 1 2 77 3 87 Primer D 1 2 56 3 48 Primer E 1 22 2 29 3 37 Primer F 1 26 2 24 3

~~W-CE

.1 pCT/US88/020 2 8 WO 88/10289 EXAMPLE 4 The primer solution from Example 1 was used to coat test pieces of natural polyethylene which were prepared as in Example 1.

A single coating of the primer was applied to both surfaces to be bonded and allowed to dry in air under unforced conditions for various periods before completing the bond with Loctite 406 cyanoacrylate adhesive. The bonds were aged at 22C0 for 24 hours and tested as in Example 1. Test pieces with no primer coating were otherwise bonded and tested as above.

Details of drying times and test results (bond strengths) are in Table 4.

TABLE 4 ON-PART LIFE Drying Time Before Bonding Tensile Shear Bond Strength (kg/cm 2 Polyethylene/Polyethylene seconds 120 300 600 1,800 3,600 14,400 Run 1 80 67 58 56 70 52 34 34 Run 2 77 72 53 60 62 38 40 30 Run 3 87 67 61 58 36 29 Controls with no primer gave zero bond strength under above conditions.

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Claims (13)

1. 3. The method of claim 2 wherein the solvent is selected from acetone, methyl ethyl ketors, 1,1,1-trichloroethane, methanol, 1,1,2-trichloro-1,2,2- trifluoroethane and mixtures thereof with each other and with other solvents.
2. 4. The method of claim 2 wherein the solution of at least one diazabicyclo or triazabicyclo compound in the solvent has a concentration of 0.001 to 30% weight/volume. The method of claim 2 wherein the solution of at least one diazabicyclo or triazabicyclo compound in the solvent has a concentration of 0.01 to 2% weight/volume.
3. 6. A two-part adhesive system comprising an alpha-cyanoacrylate -13- adhesive and (11) a primer comprising at least one diazabicyclo or triazabicyclo compound selected from; 1,5-diazabicyclo[4.3.0]non-5-ene having the formula: (1) 1,8-diazabicyclo[5.4.0]undec-7-ene having the formula: and 1,5,7-triazabicyclo(4.4.0]dec-5-ene having the formula: N* N
4. 7. The two-part adhesive system of claim 6 wherein the primer also comprises an organic solvent in which the diazabicyclo or triazabicyclo compound is stable. 8, The two-part adhesive system of claim 7 wherein the solvent is selected from acetone, methyl ethyl ketone, 1,1,1-trichloroethane, methanol, 1,1,2- trichloro-1,2,2-trifluoroethane and mixtures thereof with each other and with other 0 solvents.
5. 9. The two-part adhesive system of claim 7 wherein the solution of the at least one diazabicyclo or triazabicyclo compound in the solvent has a concentration of 0.001 to 30% weight/volume.
6. 10. The two-part adhesive system of claim 7 wherein the solution of at least one diazabicyclo or triazabicyclo compound in the solvent has a concentration of 0.01 to 2% weight/volume.
7. 11. An adhesion-promoting primer composition for use in bonding non- polar substrates comprising at least one diazabicyclo or triazabicyclo compound selected from; 1,5-diazabicyclo[4.3.0]non-5-ene having the formula: A -14- T 0 I :c- N 1,8-dlazabicyclo[[5.4.0]undec-7-ene having the formula: N and 1,5,7-triazabicyclo[4.4.0]dec-5-ene having the formula: (III) in a solvent selected from acetone, methyl ethyl ketone, 1,1,1- trichloroethane, methanol, 1, 1,2-trichloro-1,2,2-trifluoroethane and mixtures thereof g with each other and with other solvents.
8. 12. The primer composition of claim 11 wherein the solvent is an I azeotropic mixture of 1,1,2-trichloro-1,2,2-trifluoroethane with acetone.
9. 13. The primer composition of claim 11 or 12 wherein the solution of the at least one diazabicyclo or triazabicyclo compound in the solvent has a concentration of 0.001 to 30% weight/volume.
10. 14. The primer composition of claim 11 or 12 wherein the solution of the S at least one diazabicyclo or triazabicyclo compound in the solvent has a concentration of 0.01 to 2% weight/volume.
11. 15. The method of claim 1, substantially as hereindescribed with reference to any on oof the Examples.
12. 16. The two-part adhesive system of claim 6, substantially as hereindescribed with reference to any one of the Examples. A -1 w 2
13. 17. The primer composition of claim 11, substantially as hereindescribed with reference to any one of the Examples. DATED this day of October 1991. LOCTITE CORPORATION By their Patent Attorneys: CALLINAN LAWRIE 0. 0* 0 *0* 00 0 0 0 000 S 0000 0* 00 S 0*00** 000000 SO OS 0S 0005 S so jo 5e050* 00*. 5*00 *0 S 00 S ~A v.~ 5 p. 44 16- Ii 1' INTERNATIONAL SEARCH REPORT International Applicationl No,~~nj~p3 0 0 1. CLASSIFICATION OF SUOJ9CT MATT1111 fit Several elfissiflearijon symb~ols aiOly,, dCl a~ According to iileindtional lptent Cta~silattfl tIpCI or le both Nattional Classifiation and IPC ThT 1 OL. 1 oog 11 FIELDS SEARCHED Minimum Qocurnentilion Sercheid ClassificationSystem ______Classification Symmsl UJ,.S. 106/287.Ri 287.21 156/31tl 311.2 (ION'T" ON SUPP 1 sMTr 2) ocumentation Sifaiched other than Minimum Oocumonlaion to Ihe Extent that such Documents are Inclujded in the Fields Searched I 111, DOCUMENTS CONSIDERED TO BEi RELEVANTI Category C43t1Atrn Oft 004um06, 11 ivith 'indication. wre 1111r1 0111110 Of the relyyzint vasiago #2 Relevant to Claim No,' A J?ff A, 435 ~,004 (YC""7ZAWA 7"D AL) 23 7,ohruar'y 1068 Sm' Enpllth trn!!,tion ahatra.ct- A US, A, .3,761,436 (XAS~i1,4OMO FT AL) amt 64-65, col., 3 linis 27-30 Special categories ot clted documrents: 10 later documient tPublished alter the iterrnational riling data docuni deritig lite general stale of the aft Nhc .s not or priority date and niot in Conflict with the application but considered to bet ot Part'uiar relevance c ted to understand the principle or theory underlying the earlier documrent but published on or alter the international document of particular rtevsrico; the claimed invention tiling date cannot be considered novel or cannot be considered to "L document which ma)- throw doubts on priority claimls) or involve an Inventive stop which is Cited to esablfsh the Publication data ot another 'Y document of particular relevance! the claimed invention citation or other special reason las Spec fled) cannot be considered to irvotie an inventive step wvhen the "0'l document referring to an oral disclosu e, use, exhibition or document Is combined with one or more other such docu. other mneans Merits, Such combination being obvious to a person skilled document published prior to the international tiling date but ri1 the art later than the priority date claimed document member of the same patent family IV, CERTIFICATION Date ot the Acttual Completion at the International Search Date at Mailing of this International Search Report 04 August 1988 2 6 SE.P 1988 lnterrratloral Searching Authority SIgnature 1 A u Ofic L ISA/US Form POTASA00 (wond she-of) (Sev.11-a7) t A Iilqfationl Application No, PCT/US88/02028 FURTHER INFORMA'TION CONTINU90 FROM THE SECOND SHEET I 3S CL us 1. CLASSIFICATION OF SUBJECT MATTER (CONT.) -156/314; 156/331.2 427/412.1; 427/412.3 540/473; 540/567 544/279; 544/282 11. FIELDS SEARCHED (CONT.) 427/412.1; 412.3 540/473; 567 544/279; 282 V C] OBSERVATIONS WHERE CERTAIN CLAIMS WERE FOUND UNSEARCHA13LE I Th~is international search reort has riot bioon esabished in rospect of certain ctaims under Artotlo t11(2) ta lfor the following roasonsl IQ[ Claim numliors because they rotate to subloct matter 14 not required to be searched by this Authority, namely: Claim number$ because they relate to ports ot the international application that do not comply with the prescribed require. ments to such an itont that no meaningtul international search can be carried out 11, gpociflcaityi 3. 3 Claim numbers because they are dependent claims mot drafted In accordance wilth the second and third sentences of POT Rule 8.4(a), V1,~ OBSERVATIONS WHERE UNITY OF INVENTION IS LACKING 2 This International Searching Authority found multipie Inventions In this International application as toliowst t, As atl required additional search tees were timely paid by the applicant, this International search report covers all searchable claims of the international application. As only some of the required additional search tees were timef paid by the applicant, this International search report covers only those claims of the International application for which lees were paid, specifically claims: 3,M No required additional search lees were timely paid by the applicant. Consequently, this international search report 19 restricted to the Invention first mentioned In the claims; It Is covered by claim numbers: 4.]As alt searchable claims could be searched without effort justifying an additional tee, the International Searching Authority did not invite Paymert of any additional fee. Remark on Protest El The additional search lees were accompanied by applicant's protest, C] No Protest accompanied the payment of additional search tees, Form PCTA1SA210 tsLupowruwit 0*0 (PaIv, 14-7)